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11.
The authors prepared under experimental-industrial conditions paper indicator systems for the express identification of microbes, including carbohydrate discs (by the method of Nikitin et al.), and newly worked out types for the determination of the activity of cytochromoxidase, urease, indol formation, and indicator amino acid decarboxylases (lysin, ornithin, arginine). The use of paper indicator discs proved to be expedient for rationalization of laboratory diagnosis of bacterial intestinal infections.  相似文献   
12.
The effect of helium-neon laser radiation (lambda = 633 nm) given to E. coli K-12 cells of various genotypes 4 h following X- or alpha-irradiation was shown to increase the number of viable cells. The irreversible ingradient of a radiation injury to cells remained invariable during the first 60 min after irradiation its values being minimal.  相似文献   
13.
Neurospecific and neuro-nonspecific isozymes of glycolytic enzyme enolase known to be molecular markers of neuronal and glial cells respectively were isolated from human brain. Using immunoenzyme assay, the content of these proteins was measured in the brain of 7-13-week human embryos and adult subjects. The content of both isoenzymes gradually increases attaining constant level in 10-13-week embryos. Relative content of neuro-nonspecific enolase in the brain of 10-13-week embryos is 1 1/2 times higher than that in adults, whereas the content of neurospecific enolase amounts only to 2% of its level in the adult brain.  相似文献   
14.
Structural changes in the regional popliteal lymph nodes have been studied in C57Bl/6 male mice at the peak of the reaction "graft-versus-host" to H-Y antigen. Morphological and morphometrical investigations have been carried out in three groups of males (10 animals in each group). The first group includes intact animals (the first control group). To the males of the second group (the second control group) lymphoid cells are inoculated from intact C57Bl/6 females. To the males of the third group (experimental group) lymphoid cells are inoculated from H-Y antigen immunized C57Bl/6 females (anti-H-Y effector lymphocytes). The popliteal lymph nodes of the male mice from the third group twice increase in their size comparing to those in the control (the first and the second groups). Miotic activity increases in them 4.5 times, amount of cellular blast forms in medullary cords--4 times and 10 times--in the light zone of the cortical substance. Ratio of macrophages and eosinophils in structural components of the lymph nodes studied changes; this is, evidently, connected with massive destructive progresses, that take place in the lymph nodes of the animals from the third group. The results of the morphological investigations are in agreement with the hypothesis suggested, explaining the mechanism of development of the regional reaction "graft-versus-host" to H-Y antigen, basing on idiotype-antiidiotype interaction (the idiotypic network in the immune system).  相似文献   
15.
At the international tournament in 1982 in Moscow and Tashkent 254 leading footballers of the world from 10 national young combined teams have been undergone an anthropological examination. In all the persons examined main total body dimensions, fat mass in per cent and somatotype after B. Hint and J. Carter have been determined. The leading footballers of the world are of more than middle height and tall, the body mass is proportional to its length, the fat mass values are not great. Their specific somatotype is well-balanced mesomorphic and ectomesomorphic types. The average somatotype of the footballers examined can be presented as 1.7-5.6-2.6. The data obtained can be used when selecting and complexing national combined teams with perspective sportsmen.  相似文献   
16.
In the thymus of normally fed pregnant rats the plasma membrane enzymes dipeptidyl peptidase IV (DPP IV) and alkaline phosphatase (alP) were found in cortical and medullary lymphocytes (thymocytes). Plasma membrane aminopeptidase A (APA) and adenosine monophosphate hydrolysing phosphatase (AMPP) were present in cortical reticular cells. In medullary reticular cells, aminopeptidase M (APM), gamma-glutamyl transferase (GGT), adenosine triphosphate (ATPP) and thiamine pyrophosphate (TPPP) cleaving phosphatases were detected. Medullary reticular cells did not contain APA. Lysosomal DPP I and II, acid phosphatase, acid beta-D-galactosidase, beta-D-N-acetyl-glucosaminidase, beta-D-glucuronidase and non-specific esterases occurred especially in macrophages at the corticomedullary junction. The 21-day-old fetal thymus showed a similar reaction pattern as the maternal organ except for APA which was absent before birth. After treatment of the pregnant rats with valproic acid (VPA), salicylic acid (SA), streptozotocin (ST) and retinoic acid (RA) APA showed an increase in activity in the thymic cortex. In addition, ST and RA induced AMPP, ATPP and TPPP activity in cortical reticular cells up to the same pattern as in medullary reticular cells. After ethanol (ET) administration severe damages occurred. The thymic cortex was free of DPP IV-positive lymphocytes; the medullary reticular cells showed reduced or no GGT and occasionally an increased APM activity. Dexamethasone (DEXA) given to normal or zinc-deficient rats produced the most severe lesions; thymocytes with DPP IV activity were completely absent in the cortex and medulla. In Zn-deficient pregnant rats similar alterations were observed as after ET.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
17.
Several nucleoside 5'-triphosphate analogs were investigated as inhibitors of human hepatitis B virus replication. Different analogs inhibited DNA synthesis differently, 3'-azido-2',3'-dideoxythymidine 5'triphosphate being the most active compound. This inhibitor blocked DNA synthesis by 50% at inhibitor: substrate molar ratio 1:8, and by 80% - at 1:1. The hypothesis is formulated that 3'-azido-2',3'-dideoxythymidine 5'-triphosphate inhibits RNA directed viral DNA replication due to incorporation of this compound into 3'-termini of newly synthesized DNA chains. The phenomenon observed opens new possibilities for chemotherapy of acute and chronic human hepatitis B.  相似文献   
18.
19.
A study was made of the time course of lesser circulation (LC) in 80 patients with acute transmural myocardial infarction and in 20 patients with chronic coronary heart disease with the help of chest x-ray. A possibility of preclinical detection of left ventricular insufficiency was confirmed. The capacity of roentgenography to reflect objectively the time course of LC disorder and its correlation with primary determination of a degree of changes, age, cardiac sizes, the expression of aortic atherosclerosis, pleurocardiac reactions and site of myocardial infarction were defined.  相似文献   
20.
Dynamics of neuronal activity in the cingulate gyrus (CG) was investigated during the sleep-wake cycle (SWC) of free-ranging cats. The highest activity rate was found to occur in 65.4% of neurons during active emotional consciousness (EC) and the so-called emotional phase of paradoxical sleep (PS), while firing rate decreased during passive consciousness (PC) and slow-wave sleep (SS). Peak firing rate was observed during SS in 15% of neurons, while divisions of activity between stages of the SWC remained the same in 19.6%. In addition, discharge patterns in 75.2% of neurons changed consistently in step with phase shifts. More particularly, neurons fired during EC and PS with single action potentials with a more or less even time distribution, whereas a burst-phase activity pattern occurred in the course of SS. Firing rate declined (in 42.6% of units) or remained unchanged (in 50.4%) in the majority of CG neurons (even amongst those manifesting highest activity during EC and PS) as episodes of isolated EEG arousal developed (whether in the context of SS or as PS wore off). This would indicate that the CG actually contributes to shaping the behavioral state of consciousness. The CG, therefore, as one of the higher divisions of the limbic system, must play a major part in controlling the basic mechanisms of the SWC, as well as emotionally motivated processes evolving in the cycle.I. S. Beritashvili Institute of Physiology, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Neirofiziologiya, Vol. 21, No. 6, pp. 832–840, November–December, 1989.  相似文献   
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