Evaluation of cell proliferation kinetics by the differential staining of the sister chromatids at 2 points of cell fixation

Lymphocyte proliferation in blood cultures from 23 normal individuals was studied. A simple method of evaluation of cell proliferative kinetics with sister chromatid differential staining using two different points of cell harvesting was suggested. It was shown that different composition of tissue culture medium plays a significant role during the cell exit from G0 stage, the mean doubling generation time of cellular population remaining constant.     

Effect of helium and argon on the oxygen uptake by lymphocytes

The effect of inert helium and argon gases on the tissue respiration has been studied on lymphocyte suspensions of white rats. It is shown that normoxic helium-oxygen mixture induces almost a two-fold increase of the O2 uptake by lymphocytes as compared with the control (air). No deviations in the value of the studied parameter are revealed in case of replacement of nitrogen from air by argon. Significance of the membrane structure in realization of effects of inert gases is under discussion.     

A complex medico-genetic study of West Siberian populations. I. Formulation of a problem. Goals and objectives of the study. Population genetic characteristics of Northern Khanty

Purposes and tasks of the complex medical and genetic study of West-Siberian inhabitants were formulated. Demographic parameters for the North Khanty inhabitants, such as size, dynamics of the tertiary sex ratio, marriage structure and migration processes were presented. Mating and intrapopulation migration patterns are determined by spatial subdivision, because of the vast territory and the traditional way of life, and by isolation by distance. Index of the isolocal endogamy equals to 0.364. The portion of mixed marriages is 22.7% and that of the gametic contribution of immigrants - 7.3%. Inbreeding coefficient by isonymy is 0.00097. Effective population size of the five subpopulations studied as a whole is 25% of their total number.     

Determination of inhibition sites during hydrolysis of polydeoxyribonucleotides by exonucleases III from Bacillus amyloliquefaciens and Escherichia coli

The influence of the primary structure of polydeoxyribonucleotides on the rate of hydrolysis with exonuclease III from Bacillus amyloliquefaciens and Escherichia coli was investigated. The substrates used were synthetic oligodeoxyribonucleotides and pBR 322 DNA fragments labeled with 32P at the 5'-termini of one of the chains. According to the data from polyacrylamide gel electrophoresis performed under denaturing conditions, the hydrolysis of these substrates by unsaturating concentrations of B. amyloliquefaciens and E. coli exonuclease III proceeds with several reproducible "stops". The decrease of the reaction rate was shown to take place just before the pyrimidine blocks in the digested DNA chain.     

Role of cell-mediated immunity in the resistance to experimental sporotrichosis in mice

The in vitro activity of several new imidazoles, cloconazole, sulconazole, butoconazole, isoconazole and fenticonazole, were compared with those of amphothericin B, flucytosine, and three azoles: econazole, miconazole and ketoconazole against isolates of pathogenic Candida. A total of 186 clinical isolates of 10 species of the genus Candida and two culture collection strains were tested by an agar-dilution technique. Isoconazole was the most active azole, followed by butoconazole and sulconazole. Differences between some of the species in their susceptibility to the antifungal agents were noted. Sulconazole and cloconazole had the highest activity in vitro against 106 isolates of C. albicans. Butoconazole and isoconazole were also very active against isolates of C. albicans, and were the most active azole compounds against 80 isolates of Candida spp.     

DETERMINATION OF GUSTATORY SUCROSE THRESHOLD IN WATER BY USE OF A LINEAR SUCROSE GRADIENT

A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).     

应用气-质联用仪测定三种螺旋藻中的甾醇成分

应用GLC/MS联用仪对室内培养的钝顶螺旋藻(Spirulina platensis (Nordstedt) Geitler)、极大螺旋藻(S.maxima (Stechell & Gardiner) Geitler)和盐泽螺旋藻(S.subsalsa Oerst)的甾醇成分进行了测定。从钝顶螺旋藻和盐泽螺旋藻中共分出11个相同的甾醇组分:胆甾醇、胆甾烷醇、芸苔甾醇、麦角甾醇、海绵甾醇、菜子甾醇、豆甾醇、24-乙基-Δ~(5,7,22)-胆甾醇、β-谷甾醇、异岩藻甾醇和4α,23,24-三甲基Δ~(5,22)-胆甾醇;从极大螺旋藻中只分离出8个甾醇组分。其中胆甾醇含量最高。4α,23,24-三甲基-Δ~(5,22)-胆甾醇为蓝藻中首次报导。