It was demonstrated that the dynamics of muscle oxygen utilization can readily be measured using dual wavelength hemoglobin oximetry. This method can be used for muscle training exercise and also for evaluation of exercise performance where the anaerobic threshold must be avoided. It was shown that CW imaging technology gives images along the surface of the muscle while the time resolved spectroscopy gives images transverse to the muscle.

Polarized light can be used to obtain images of superficial tissue layers such as skin and some examples images are presented. This paper present a study of the transition of linearly polarized light into randomly polarized light during light propagation through tissues. The transition of polarization was studied in polystyrene microsphere solutions and in chicken muscle and liver. The transition is discussed in terms of a diffusion process characterized by an angular diffusivity for the change in angular orientation of linearly polarized light per unit optical path traveled by the light. The results are consistent with the hypothesis that birefringent tissues randomize linearly polarized light more rapidly than nonbirefringent tissues. The results suggest that polarized light imagin of skin tissues based only on photons backscattered from the superficial epidermal and initial papillary dermis because the birefringent dermal collagen rapidly randomizes polarized light. This anatomical region of the skin is where cancer commonly arises.

The refractive index matching of components of a highly scattering tissue has a strong influence on its transmittance, reflectance, polarization and coherence what can be considered as a new approach for tissue spectroscopy, imaging, laser therapy and surgery. Experimental data for in vitro, ex vivo, and in vivo studies of various solutions, gels and oils action on optical properties of human tissues are presented. The dynamics of tissue optical properties depending on matter diffusion rate within tissue is studied. The possible application of refractive index matching effect for tissue spectroscopy, imaging and thermotherapy is discussed.

Imaging through biologic tissue relies on the discrimination of weakly scattered from multiply scattered photons. The degree of polarization can be used as the discrimination criterion by which to reject multiply scattered photons. Polarized light propagation through biologic tissue is typically studied using tissue phantoms consisting of dilute aqueous suspensions of microspheres. We show that, although such phantoms are designed to match the macroscopic scattering properties of tissue they do not accurately represent biologic tissue for polarization-sensitive studies. In common tissue phantoms, such as dilute Intralipid and dilute 1-micrometers -diameter polystyrene microsphere suspensions, we find that linearly polarized light is depolarized more quickly polarized light. In dense tissue, however, where scatterers are often located in close proximity to one another, circularly polarized light is depolarized similar to or more quickly than linearly polarized light. We also demonstrate that polarized light propagates differently in dilute versus densely packed microsphere suspensions, which may account for the differences seen between polarized light propagation in common dilute tissue phantoms versus dense biologic tissue.

The EMPHO SSK is a scanning micro lightguide spectrophotometer constructed for 3D-imaging in all tissues of humans and mammals. By monitoring of intracapillary hemoglobin oxygenation and concentration very precise information of the microcosm of the oxygen supply level of tissues can be gained. Measurements in skin and liver revealed that on the basis of numeric data obtained by optical remission techniques 3D-images can be constructed which provide information on functional structures of intact organs.

Formulas relating to the diffraction of focused Gaussian beam from a narrow blood microvessel have been derived. Vessel has been considered as a set of moving random screens. The correlation function of intensity fluctuations of statistically inhomogeneous biospeckles has been studied.

243 patient of essential hypertension were examined with the help of Doppler-Laser Flowmetry, optical photometry. Flowmetry was used to measure vasomotion and blood flow after arterial compression, decompression and venous hyperemia were held. New Doppler-Laser flowmetry diagnostic test of functional condition of microcirculation was worked out of find precapillary and postcapillar resistance. Precapillary resistance included next basis parameters: vasomotion with high frequency and low amplitude, latent time after decompression, large postocclusive reactive hyperemia, absent venous hyperemia. Postcapillar amplitude, little or absent postocclusive reactive hyperemia, large venous hyperemia. This test-method was applied to select pathogenetic treatment of essential hypertension.

The biophysical approaches to the analysis of the biopower characteristics of glucose and insulin metabolism are reviewed in the lecture on example of natural models of glucose-insulinic violations for the patients with atherosclerosis, non-insulin dependent diabetes mellitus and heritable predisposition to them. The analysis of designed mathematical model of a plasma glucose level regulation is performed. It was used as the basis of the original concept of a cell membranes pathology role in the pathogenesis of indicated forms of pathology.

Many disease processes, such as scirrhous carcinoma of the breast and atherosclerosis physically manifest themselves as changes in the mechanical properties of the involved tissue. Optical evaluation of the mechanical properties of biological tissues offers methods that can directly provide information regarding the state of health of both hard and soft tissue. Clinically, this information may be used for diagnostic purposes. Since all biological tissues display viscoelastic behavior and therefore exhibits a time dependence of their mechanical behavior, the important quantities for evaluating the mechanics of tissue under load are those that reflect this time dependence. For example, by evaluating the retardation spectrum of the tissue, the underlying molecular processes that govern the mechanical behavior may be elucidated. Understanding these spectra may provide insight into pathological processes and also provide some guidance for the development of synthetic materials or engineered tissues to replace damaged or pathological tissue. Thus, there is a need for methods that directly assess the time rate of the mechanical response of tissue to an imposed load. Herein, a few such methods will be discussed and applications to biomaterials and medical diagnostics will be discussed.

Ultra-short IR laser pluses were transmitted through excised female breast tissue. The resulted signal was recorded by a streak camera with a time resolution of the order of a few ps. Experimental data of the temporal spread of the ultra- short pulse during the transmission through the tissue have been analyzed using the Patterson analytical expression derived from the diffusion theory. This resulted in the calculation of the absorption and scattering coefficients, which are related to the optical characteristics of each type of tissue. A streak camera has detected early arriving photons of 100 fs laser pulses transmitted through highly scattering media. Due to their partial spatial coherence they are affected by diffraction caused by small hidden discontinuities. Experimental data of the patterns are analyzed using Fresnel diffraction theory and then corrected accordingly. Sum-mm hidden objects were scanned and imaged. Diffraction correction resulted in a significantly improved contrast of the hidden object's image.

The autofluorescence of the skin is known to originate form several different fluorphores located at different locations in the skin. The autofluorescence spectrum measured at the surface of the skin however does not only reflect the presence of different fluorophores in the sin. On its way to the surface of the skin the fluorescence spectrum is strongly influenced by the optics of the tissue. Not only are several absorption dips present in the spectra, relating to known and well characterized absorbers such as oxyhemoglobin, it is also very likely that the shape of the measured autofluorescence spectrum is influenced by scattering of light. The scattering coefficients are known to change only slowly with wavelength. Scattering artifacts in fluorescence spectra are therefore much more difficult to detect than absorption artifacts.

Subsurface photodisruption is shown to be an effective tool for cutting beneath the surface in human sclera. Using a dehydrating agent to reduce scattering by index matching, photodistruption is possible anywhere in the volume of the sclera. We examine incision in human sclera in vitro using scanning electron microscopy. We found a disorganized material filling the incision and penetrating into the adjacent tissue.

We explore enhanced backscatter from a random medium using time-resolved optical phase space measurement, i.e. measurement ofjoint position and momentum (x, p) distributions of the light field as a function of propagation time in the medium. Enhanced backscatter is a coherent effect and is not predicted by radiative transport theories. By using a low-coherence source in a heterodyne detection scheme, we observe enhanced backscattering resolved by path length in the random medium, effectively providing timing resolution. Such time-resolved studies are important for exploring the evolution of optical coherence as a function of penetration depth in the random medium. Optical phase space methods provide a visual as well as quantitative method of characterizing the spatial coherence properties and wavefront curvature of the input and scattered fields. These techniques may provide new venues for using optical coherence in medical imaging.

A real time, high-resolution coherence gating system to image through turbid media has been demonstrated. Using the technique of photorefractive holography with MQW devices, high-resolution depth resolved images through 16 MFP of scattering depth have been recorded. The fast response time and the high optical quality of the MQW devices allowed images to be acquired, in real-time, direct to a video cassette recorder. We also demonstrate the use of sources of low temporal and spatial coherence to record holograms through solid samples. The reduction of speckle noise is discussed.

Optical coherence tomography (OCT) is a new imagin modality capable of recording cross-sectional images of transparent and semi-transparent structures with a resolution on the order of 10 micrometers . Classical OCT imags the distribution of backscattering and -reflecting sites within the sample. However, as is known from microscopy, many objects yield only a poor image contrast if imaged on a pure intensity basis. These objects may, however, change other properties of the light which can be used for improving the image contrast. This forms the basics of advanced optical contrast enhancement techniques. We report on recent results were obtained with two of these techniques: polarization sensitive OCT and differential phase contrast OCT.

This paper presents several milestones in the development of techniques to be used as an optical biopsy for dermatology. The instrumentation for multiphoton excitation microscopy as applied to in vivo human skin is described. We compare multi-photon excitation microscopy and reflected light confocal microscopy for the microscopic observation of human skin in vivo. Multi-photon excitation is induced by a 80 MHz pulse train of femtosecond laser pulses at 780 nm wavelength. This nonlinear microscopic technique is inherently suitable for tissue fluorescence imaging because of its deeper penetration depth and lower specimen photodamage. This technique has non-invasively obtained tissue structural information in human epidermis and dermis. Confocal light microscopy based on a white light source, or a laser source can provide video-rate image acquisition with high resolution and high contrast. The relative merits of these two techniques can be identified by comparing 3D resolved images obtained from the forearm skin of the same volunteer. Optical low coherence reflectometry is another technique to image human skin in vivo. The application of Fourier transform analysis to the surface structure of skin is described as a method to characterize the skin surface topography.

The lymph flow velocity in microvessels of rat mesentery was investigated by using biomicroscopic manual frame-by-frame technique with image processing system and speckle- interferometrical method. Lymph flow was observed in the majority of lymphatics. Lymph flow was registered in microvessels with phasic contractions and functioning valves. The lymphocytes motion in flow was measured. It was established that mean lymph flow velocity increased in vessels with phasic contractions and moderate concentration of lymphocytes in flow. The application of speckle- interferometry allowed us to estimate lymph flow on the whole with all stops, the increases and decreases of flow velocity. The parameters both of changes of a mean velocity and of spatial-temporal velocity distribution in lymph flow were calculated. Temporal changes of the parameter V showed a shuttle-type character of lymph flow velocity.

Slit-lamp based laser Doppler measuring system was developed for in vivo measurements of blood flow in vessels of human conjunctiva. The level of incident laser irradiation power corresponds to the eye safety requirements. Bi-direcitonal laser Doppler technique provides measurements of absolute flow velocity. Results of in vivo experiments with a model of blood vessel are presented.

A method for the absolute determination of the fraction of Doppler-shifted photons in light scattered by mixture of moving and stationary scatterers is proposed. It based on the theoretical approach developed in our group to predict the signal power fluctuations of an integrated Doppler- induced speckle pattern on the photodetector. A benefit of using a multimode step-index optical fiber as a scattering sample-to-detector interface is considered. An experimental validation of the method has been performed and experimentally obtained data are in a good agreement with the theory. As one of a practical application of the method the fraction of Doppler-shifted photons in light backscattered from human skin has been measured and the results are reported.

The results of statistical analysis of Doppler spectra of scattered intensity, obtained from tissues of oral cavity membrane of healthy volunteers, are presented. The dependence of the spectrum shape on the size of integrating aperture and dependence of the spectral moments of Doppler signal on cutoff frequency are investigated. Some physiological tests in combination with LDF technique are suggested as a new diagnostic tool.

Simulation of processes of scattering in micro volume, which contains a small number of scatters, has been carried out. First-order statistics of statistically-inhomogeneous speckles have been analyzed. Skewness and excess of probability density function of intensity fluctuations and dependence of these characteristics on the number of scatters have been investigated. Diffraction of coherent irradiation from highly scattering medium with a small number of scattering events has been studied. The range of validity of DWS has been found.

We have developed a new theoretical description of the optical coherence tomography (OCT) technique for imaging in highly scattering tissue. The description is based on the extended Huygens-Fresnel principle, valid in both the single and multiple scattering regimes. In contrast to previous OCT models, we have included the so-called shower curtain effect, which manifests itself in a standard OCT system with diffuse backscattering from the tissue discontinuity being probed, and a distance between the focusing lens and the tissue. We demonstrate that inclusion of this effect in the model leads to a strong increase in the heterodyne signal. The theoretical analysis is verified by measurements on samples consisting of aqueous suspensions of microspheres, and solid phantoms. Finally, we discuss the use of our new theoretical model for optimization of the OCT system.

Polarization relaxation in the disordered multiply scattering media with non-zero absorption is studied. Experiments with phantom scattering media such as water suspensions of polystyrene spheres and diluted milk have been made to analyze the dependencies of polarization degree of multiply scattered light on the absorption coefficient for monodisperse and polydisperse scattering systems. The concept of optical path distribution is used for phenomenological interpretation of the obtained results. Monte-Carlo simulation is applied to obtain the distributions of the effective optical paths for given scattering and absorption conditions.

Method for inhomogeneous media probing ny means of the contrast measurements for multiply scattered speckles is considered. Value of the speckle contrast is obtained on the basis of the discrete scatter model as the integral transform of probability density function of differences of effective optical paths characterizing the scattering system. Pathlength distributions were simulated for different detection conditions and optical properties of scattering medium by using Monte-Carlo technique. Comparison of the discussed approach with traditional method of diagnostics and visualization of turbid media such as direct measurements of the scattered light intensity is made.

We have non-invasively studied the motor cortex hemodynamics in human subjects under rest and motor stimulation conditions using a multichannel near-IR tissue spectrometer. We obtained optical maps of oxy- and deoxy-hemoglobin concentration changes in terms of amplitudes of folding average, power spectrum and coherence at the stimulation repetition frequency, and the phase synchronization index. Under periodic motor stimulation conditions, we observed coherence and phase synchronization of the local hemodynamic changes with stimulation.

Measurement of retinal visual acuity (RVA) in 170 patient with different types of cataract (senile, complicated, posterior capsular ) before and after cataract extraction and also in vitro measurement of RVA with extracted cataractal lenses has shown that laser retinometer can be used for evaluating visual acuity within 0.3 - 1, practically for all types of cataract. Experimental in vitro studies of speckle-modulated laser field arising after transmission through different type of human cataractous lenses are presented. Computer analysis of digital imaging has allowed us to determine the degree of destruction of spatial coherence of scattered laser beam and the angle of resolution of retina using Retinal Analyzer of Vision (AROLI) in diagnosis of cataract. Approbation of topographic digital videosystem used for determing the extent of opacities in cataractous lenses in vivo and its use in measuring diapasons RVA for different type of cataracts is presented. The system consists of the modified slit lamp, CCD camera ( ELECTRIM) and PC PENTIUM with corresponding software.

The computer method of visual acuity measurement is described in the paper. Optotypes of different size and orientation are presented to the subject who answers if he recognizes them or not. Basing on the subject's answers, recorded by computer, we construct psychometric function from which we calculate parameters describing VA. The method can be used in investigation of the accommodation or changes in overall state of the subject.

The content of ceruloplasmin (Cp, multicopper oxidase, CE 1 .16.3. 1) was measured in samples of breast milk during the first month of lactation using enzymatic and inimunochemical assays. The 4-fold decrease of Cp concentration in the milk during 20 days of lactation period was demonstrated. It was shown that copper is almost completely bound to Cp. Milk ['251]-Cp administered per os to six day-old rats was transferred across the gastric and intestinal mucosa and entered the bloodstream. The special calculation shown that newborns fed by baby formula (BF) receive magnitude excess of copper ions which not packing into safety molecular cover. It is possible that the artificial feeding is the factor interfering with the copper balance in newborns and causing various copper associated disease. For the solution of this problem an experimental model of the laser analyzer, permitting selectively to measure coordinate-bound copper in dispersing fluids is design.

Cataract is one of the main reasons of blindness now. The essence of this pathology is opacification of the eye lens. The main method of cataract treatment is microsurgical extracapsular cataract extraction (ECCE) with implantation of an intraocular lens (IOL). At present, the types of JOLs differ in its optical parameters and structural features. We performed the comparative study of various types of lOLs in respect to visual rehabilitation of the patients. After the implantation of the IOL we measured the visual acuity, the color perception, the post-operative refraction of the eye, the IOL decentration, the cell adhesion onto the surface of the IOL and some other parameters. In addition, we studied the dependence of the patient's visual discomfort caused by various optical effects and aberrations upon the IOL type. As a result of this investigation we found a number ofcorrelations between the IOL types and some characteristics ofthe patient's vision. The consideration ofthe IOL features determinates the indications and contraindications for using of different types ofthe lOLs and promotes to improving ofquality ofpatient's vision.

The diffusion of glucose with various concentrations through human sclera and cerebral membrane in vitro was studied. The dynamics of this process was monitored by time-dependent weight and optical measurements. Glucose administration induces the diffusion of matter and as a reslut the equalization of the refractive indices of collagen fibrils and ground material, and corresponding changes of transmittance spectra of fibrous tissue. Transmittance spectra of the human scleral and cerebral membrane samples impregnated by glucose were measured. Investigation of diffusion process in scleral samples, previously dried and swelled in distillated water was performed. Experimental results are presented.

The process of photobleaching of fluorescence of NADH in gelatin gel under UV irradiation has been studied. An attempt to evalute the NADH fluorescence contribution to 460-480 nm fluorescence of the samples from bleaching data has been made.

In this work, the temporal behavior of autofluorescence of epidermis samples under UV-irradiation has ben studied. The samples were prepared using surface epidermis stripping technique. Fluorescence spectra and kinetic curves of fluorescence intensity have been obtained. It has been concluded that the glue composition used allows the measurement of epidermis fluorescence dynamics with the first 60 min of experiment.

The theoretical investigations of laser light radiation scattered by eye lens model as a system of spheres with various parameters in case of gaussian wave were performed on the base of Mie theory of electromagnetic scattering by a single sphere and by using Bromwich formulation. The amplitude matrix of light scattering, the intensity distribution of scattered light are received. The contrast analyses of obtained intensity distributions in dependence on size and amount of scatterers were carried out. The optical constants and dimensions of the particles were varied in a range of values corresponding to the normal and pathological lenses.

This paper deals with the problem of calculating the color characteristics of light scattered by disperse systems. Multiple scattering effects were taken into account.

Some optical properties of the biological tissues and the methods of their measurements are discussed. The phantom experiments and in vivo measurements of diffuse reflectance at 830 nm of human skin immersed by various solutions and lotions are described.

In present work, fluorescence spectra of normal cervical tissue as well as some benign lesions were obtained ex vivo with 365 +/- 20 nm and 405 +/- 30 excitation. In all case of ectopia emissions from normal area appeared more intensive than from pathological one. Intensive fluorescence with specific spectral lineshape was observed on the posttraumatic scars, the main contribution to the spectrum was attributed to collagen. On the base of phantom measurement, explanation of appearance of a weak peak at 505-515 nm in tissue fluorescence spectra was proposed.

The LDMA which permits to carry out the element analysis without an additional excitement of laser plasma is described. Some results on identification and differentiation of bone tumors on the basis of measured spectral characteristics are presented.

Reflection and transmission of light are considered in stratified anisotropic structures in which layers interact in incoherent regime with light. In general case of a multilayer structure reflection and transmission matrices are obtained for arbitrary angle of incidence. The dependence of optical characteristics of the structure on its parameters are analyzed in the specific case of a chiral layer.

A numerical method, based on integral representation of Maxwell's equations, is used to calculate the scattering properties of bacterial cells.

In this paper, we described our results of computer simulations of light propagation in a multi-layer biological tissue, such as the human brain and the skin. This report includes description of optical properties of cerebral tissue and skin tissue, some technical characteristics of near-IR noninvasive techniques of the human brain and skin examination. As well as we described light beam deformation in a multi-layer tissue and general principles of our algorithms construction.

Obtaining quantified measurements of oxygen saturation of skin blood from collected diffuse reflectance spectra is complicated by the fact that blood and pigments are not distributed in skin tissues homogeneously. Using the developed Monte Carlo technique and simple multi-layered model of skin we have simulated the reflection skin spectra. The computational model contains seven layers with rough boundary surfaces. Absorption properties of the modeled skin layers are related to the real absorption spectra of pure oxy- and deoxy-haemoglobin, and water, and include different rate of blood oxygen saturation and hematocrit. Comparison of the result of the simulation with in vivo experimental results shows good agreement and validity of our skin model.

We consider photon migration in biological tissue and other highly scattering inhomogeneous turbid media. The weight Monte Carlo algorithm imitates the transport of photons between shortly separate source and detector areas of the fiber optic probe by letting the photons carry out a random walk. Considering spatial photon weight distribution on the surface of the simulated semi-infinite medium we show the influence of refractive index mismatching, absorption and anisotropy of the medium on the spatial photon weight distribution on the detector. The understanding of the role of photon portions in the detected signal is important for identification of dominating parts of the reflected light on the detector and as a corollary spatial detector depth sensitivity of back-scattered light, that is important for quantitation of many measurements of the light transport into complex turbid highly scattering media.

Results of experimental and theoretical study of the optical properties of the eye sclera controlled by administration of osmotically active chemical, such as glucose, are presented. Glucose administration induces the diffusion of matter and as a result the equalization of the refractive indices of collagen fibrils and base material, and corresponding changes of transmittance spectra of scleral tissue. Transmittance spectra of the human scleral samples impregnated by glucose were measured. The significant increase of transmittance under action of osmotic liquid was observed. The diffusion coefficient of glucose within scleral tissue was estimated; the average value is 3.45 X 10^-6 +/- 4.59 X 10^-7 cm²/sec. The results are general and can be used to describe many other fibrous tissues impregnated by osmotically active chemical agents.

Activity of molecules in biological system depends on their conformation. NMR spectroscopy study of molecule conformations requires replacement of atoms by their isotopes. X-ray diffraction study is limited by an opportunity of reception of crystal samples with perfect structure. Biological systems, for example the cell membranes, are liquid crystal systems hence have imperfect crystal structure. Molecule conformations of substances with such structure can be investigated by use of more long-wave radiation. In this case the imperfection of structure will be less essential. In this paper we show the efficiency of joint application of experimental molecular vibrational IR spectroscopy and computer simulation of spectra, with correction of force constants and electrooptical data for phase state change, in study of conformations of liquid crystal molecules.

Ligustrazine, a Chinese herb medicine has been used to treat the diseases of cardiovascular and cerebral vascular diseases in China by Chinese traditional physicians or many years. Recently, results showed that ligustrazine is a powerful hepatic vasodilator. It can greatly change the blood supply of the tissues. Due to micro-optical tissue sensor developed recently it became possible to image functional structures of tissue on the level of intact blood capillaries. In our experiment we used the Oxyscan in order to study the effect of Ligustrazine on the oxygen supply of rat liver.

Preliminary data are reported on time-resolved measurements of photosensitized phosphorescence of singlet molecular oxygen (2 = 1270 nm) excited by pulses of a copper-vapor laser in aqueous buffer solutions (pH 7.4) containing water-soluble porphyrins and bovine blood plasma. Reliable phosphorescence kinetic curves were detected after 100-500 s signal accumulation that corresponded to (1--6) x 106 laser shots. With no plasma and no oxygen purging the phosphorescence kinetics comprised the rise and decay phases with a maximum at 2.5 _ts after a laser shot. Addition of 1% bovine blood plasma (vol/vol) caused ten-fold decrease of the phosphorescence intensity. With higher plasma concentration the phosphorescence was not detected. When oxygen bubbled through the plasma-containing solutions during laser irradiation and the solution flowed at a rate of 1 .5 ml/s through the spectrophotometric cell, the phosphorescence intensity increased and was observed at plasma concentration up to 20%. The phosphorescence intensity of a 20% plasma solution was about eight fold less than that of a porphyrin solution containing no plasma. With 20% plasma the phosphorescence rise-time was in a range of 1--i .5 is, the phosphorescence decay-time was 7--8 ts. Further experiments are in progress in order to optimize our experimental set-up for measurements in whole blood serum and plasma.

We have studied photodynamic action of He-Ne laser radiation on cultures of Staphylococcus and Streptococcus anhaemolyticus been sensitized by methylene blue. The concentration of the dye was varied form 0.001 percent to 0.1 percent and radiation power density from 75 to 200 mW/cm². Irradiated strain was put into thermostat for 24 hours, then the number of colonies was counted and analyzed.

60 patients with angina pectoris were treated by IR laser radiation. We have revealed that IR laser radiation reduces antithrombogenic activity of vessel endothelium.

Transcutaneous (in the area of mesenteric lymph nodes projection) low-rate infra-red laser irradiation with the pulse rate of I 500 Hz caused increase of fluorescence of mesenteric lymph nodes lymphocytes in the green region of spectrum 24 hours after the first irradiation. This index reached its maximum on the 7th day of the experiment. Later, gradual normalization of lymphocyte fluorescence was noted. Alongside with the increase of chromatin activity we have noted change in lymphocyte percentage, which synthesized DNA and were in the state of mitosis. The maximum of S+G2+M lymphocytes increase was on the I 5th day. The study of lymphocyte red fluorescence showed the appearance of cell population in the mesenteric nodes with the increased red fluorescence which testifies to activation of cytoplasmatic structures of lysosomal nature.

Nonlinear dynamics of a simple mathematical model of the neural control of the heart rate variability is investigated. The choice of the model from known ones is justified. The range of parameter values appropriated to the cardiological data is found by computer modeling. Bifurcation diagrams and spectral densities of processes are calculated.

The four-component mathematical model of plasma glucose level regulation based on examination of 5 groups of specially selected persons was developed. During the intravenous glucose load the concentrations of plasm glucose, free and bound forms of an insulin were studied. The obtained data was utilized for creation of the indicated model. The delay sin glucose and insulin action on peripheral tissues were obtained. The increase of these delays for the patients with atherosclerosis confirms a hypothesis about value of a pathology of cell membranes in the pathogenesis of the indicated disease.

The time functions of plasma glucose and insulin obtained during intravenous glucose tolerance test were approximated by sections of Fourier series. The convincing quantitative and quality distinctions of amplitudes both phases of the first and second harmonics of decomposition of the indicated time functions are obtained. These distinctions were used as a basis of diagnostic algorithm of metabolic violations appropriate for atherosclerosis and non-insulin dependent diabetes mellitus in clinically obvious and preclinical stages.

'Me1anin screen" effect, i.e. the increase of epiderinal absorption due to UV-induced melanogenesis leads to decrease of effective doses of UVA-radiation at subsequent photochemotherapy sessions. In the work the mathematical model of melanogenesis. induced by sequence of UVA-radiation "pulses" ,is developed. Processes on cellular, subcellular and molecular levels are described. The structure of equations allows to split the problem and to consider differential equations system at given intensity, to calculate a melanin distribution and absorption coefficient, to define a new value of intensity etc. The melanin content in basal and upper layers is defined. The time and dose dependencies of epidermal absorption coefficient are determined. Thus using the presented model it is possible to inspect a modification of modes during PUVAtherapy.

On the basis of experimental data obtained at clinical examination of 5 specially fitted groups of the patients the analytical system of early diagnostic of metabolic condition appropriate for an atherosclerosis and non-insulin dependent diabetes mellitus was designed.

The diagnostic algorithm of glucose-insulinic violations for the patients with a clinically obvious atherosclerosis of coronary arteries, non-insulin dependent diabetes mellitus and persons with the heritable predisposition to these forms of pathology was designed. The realization of intravenous glucose tolerance test in specially fitted groups of patients served as basis of the algorithm.

Monitoring of tissue freezing and hypothermia during cryotherapy in real time is in the great demand for precise selective destruction of tumors. Ultrasound imaging, magnetic resonance imaging, and computer tomography techniques proposed for cryotherapy monitoring have problems associated with long acquisition time, high cost, low contrast, and poor resolution. In this paper we propose to use optoacoustic technique for monitoring of tissue freezing and hypothermia. Optoacoustic imaging is based on time-resolved detection of laser-induced acoustic waves. We studied influence of cooling and freezing on amplitude and profile of laser induced optoacoustic signals recorded from tissue phantoms (aqueous solution of potassium chromate) and canine liver. We used liquid nitrogen as a coolant of our samples. Q-switched Nd:YAG laser pulses were used to induce optoacoustic pulses. Our studies demonstrated that (1) amplitude of optoacoustic signals recorded from native tissues and aqueous solutions decreases with cooling down to the temperatures of -2 °C and 0 °C, respectively; and (2) freezing of tissues and aqueous solutions results in dramatic change in the optoacoustic signal profiles and amplitude. Our results indicate that the laser optoacoustic technique can potentially be used for real-time monitoring of freezing front in tissue with 0.5-mm spatial resolution.

Transcutaneous millisecond stimulation of the retina by electric pulses is used for diagnosis, determination of the extent of optic nerve damage, and also partial restoration of visual function in patients with glaucoma, myopia and different types of optic nerve atrophy. Correlation between the threshold of phosphen formation and duration of the stimulating electric pulses was determined experimentally in normal eyes and in eyes with various pathologies. Comparison of optical and electrical scintillating frequency gives information about the dynamic processes in the normal and pathological retina.