[Measurement of the magnetic relaxation of water molecules in biological systems by the impulse NMR technic with calculation of their volume]. / Izmerenie impul'snym metodom IaMR magnitnoi relaksatsii molekul vody v biologicheskikh sistemakh s uchetom ikh ob'ema.

Impulse sequences are presented for selective by biological system volume measurements of the times of spin--spin, spin--lattice relaxation of water molecules by means of NMR spin echo. Selectivity of the programs is based on the fact that in the presence of magnetic field impulse gradient diffusion quenching of the echo differs for water molecules limited or unlimited in their diffusion displacement by some barriers (membranes) and it also differs for molecules limited in compartments of different size. Selective measurement of the times of spin--spin relaxation (T2) of water in intracellular structures of the yeast cells gave the value 24.4 msec, which is 1.3 times lower than the specimen volume measured by standard method.

[Study of the diffusion of water absorbed on proteins by the ESR methods using a new magnetic field impulse gradient program]. / Issledovanie diffuzii vody, adsorbirovannoi na belkakh metodom IaMR, s ispol'zovaniem novoi programmy impul'snogo gradienta magnitnogo polia.

Modification of the program of impulse gradient removing anomalous suppression of the echo at small time intervals between gradient impulses is presented. The results are given of measuring the diffusion of water adsorbed on bovine serum albumin. An efficient diffusion coefficient for 20 degrees C is evaluated as 2.4.10(-6) cm2 sec at the activation energy in the temperature range 5 divided by 40 degrees C for 0.42 g H2O/g of protein and 20 divided by 50 degrees C for 0.22 g H2O/g of protein equal to 6.5 kcal/mol.

[Translation mobility of water isolated in the cells of lyophilized Cryptococcus albidus var. diffluens yeasts by the NMR impulse method]. / Issledovanie transliatsionnoi podvizhosti vody, izolirovannoi v kletkakh liofil'no vysushennykh drozhzhei Cryptococcus albidus var. diffluens impul'snym metodom IaMR.

The method of NMR spin echo in a combination with the impulse gradient of the magnetic field was used to study the self-diffusion of water isolated in the cells of lyophylized Criptococcus. A relative fall of the amplitude of spin echo (factor R) in relation to the value of magnetic field impulse gradient (g), their duration (delta) and temporary distance between them (delta). The studies were carried out in the temperature range of 20 degrees divided by 80 degrees C. It has been shown that the fraction of isolated mobile water is located in intracellular permeable compartments with an average size of 0.6.10--4 cm at 20 degrees C. The coefficient of selfdiffusion of isolated water of Criptococcus (0.25.10--5 cm2S--1 at 20 degrees C) and the activation energy of selfdiffusion (4.4 ccal/mole at 20 degrees divided by 60 degrees C) were determined, permeability of walls of water-containing compartments taken into account.

[Distribution of the dimensions of cells and intracellular structures of biosystems from measurements of the diffusion of water by the impulse gradient of the NMR spin echo method]. / Raspredelenie razmerov kletok i vnutrikletochnykh struktur biosistem iz izmerenii diffuzii vody metodom impul'snogo gradienta spinovogo ékha IaMR.

The method of impulse gradient of NMR spin-echo was applied for studying limited water diffusion in yeast cells and embryons of wheat caryopsis. Results are presented of measuring the amplitude of the echo signal depending on the intensity of the impulse gradient of the magnetic field reaching the values up to 1.7 kGs/cm. The method is suggested of determining on the basis of experimental data the distribution function parameters of the sizes of limiting cell compartments taking into account the permeability of their walls (membranes).