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31.
Repeated amputation of the lower incisors in rats carried out at the early postnatal on togenesis causes an enlargement of the salivary glands and hypertrophy of the testis with the phenomena of acceleration of their differentiation. Hypertrophy of the testes withthe mentioned action was much greater (76%) than in the case of unilateral castration at the same age. In adult animals repeated amputation of the lower incisors caused hypertrophy of the salivary glands, but failed to influence the hypertrophy of the testes.  相似文献   
32.
The intracellular and extracellular amino acid composition of an auxotrophic methionine-deficient strain of Acremonium chrysogenum was studied in respect of the content of various carbohydrates in the fermentation medium. In the presence of glucose, an intensive involvement of exogenous DL-methionine into the cell metabolism was observed at earlier stages than in the presence of dextran or succrose. The total content of intracellular amino acids was lower in the cells grown on the medium with glucose. The production of cephalosporin C depended on the intracellular content of methionine, glutamic acid and lysine.  相似文献   
33.
The cytochrome P-450-dependent monooxygenase system of the liver was studied in laboratory noninbred male rats selected according to the intensity of their initial alcohol motivation and the dynamics of these parameters was followed up during 10-day alcoholisation. It was shown that in the animals inclined to the development of alcoholism the activity of the monooxygenase system (cytochrome P-450, B5; enzymes: aminopyrine N-demethylase, aniline p-hydroxylase, NADPH-cytochrome c-reductase) is higher than in the animals noninclined to the development of this disease. 10-day alcohol consumption in the free-choice situation between water and 15% ethanol solution did not change the parameters investigated. The only exception was NADPH-cytochrome c-reductase: its activity grew in both the groups of the animals by 40-75%.  相似文献   
34.
The results of the immunophoretic analysis of H. pylori antigenic structure are presented. Along with H. pylori O-antigen, specific surface antigen of acidic nature, relatively thermolabile with characteristics similar to those of K-antigens, was detected. A diagnosticum based on the coagglutination test for the rapid detection of H. pylori specific antigens in the patients' biological fluids (coprofiltrate, saliva) by the noninvasive method was developed. The circulation mode of H. pylori in human body and its correlation with the clinical symptoms of the disease was shown. H. pylori antigens were very frequently detected (in 65 - 83% of cases) in patients with acute bacterial enteric infections: shigellosis, salmonellosis, yersiniosis, campylobacteriosis. The newly developed method seems to be promising for the rapid diagnosis of H. pylori associated infections, for the prolonged monitoring and evaluation of the effectiveness of antibacterial therapy.  相似文献   
35.
It has been shown using labelled modified AO cytofluorometry of DNP cellular thermal denaturation that the melting profiles of peripheral blood cellular chromatin in children with acute lympholeukemia (ALL) were of strictly individual, "unclassifiable" nature and were similar to those of their mothers but different from those of their fathers and healthy people, which seems in favour of a possible connection between the disease under study and the peculiarities of the mother's genotype. Similar types of deviations have been found in the structure of interphase chromatin of healthy parents of children with ALL. Such a combination of changes in the parents' genotype may prove unfavourable, increasing the birth rate of neonates with a genetic predisposition to the disease in question.  相似文献   
36.
Interaction of rubomycin (daunorubicin) chlorhydrate with dimethylformamidine diethyl acetal yielded 3'-desamino-3'dimethylformamidinorubomycin chlorhydrate (DFR). Comparative antitumor activity of DFR and rubomycin was studied on mice with respect to ascitic lymphadenosis NK/Ly and Ehrlich carcinoma, hemocytoblastosis La, leukemia P-388 and two solid tumors i. e. lymphosarcoma LIO-I and sarcoma 180. The highest antitumor effect of DFR was observed in the mice with Ehrlich carcinoma and lymphadenosis NK/Ly after the drug intravenous administration for 4 times. By selectivity of the antitumor effect DFR was inferior to rubomycin with respect to lymphosarcoma LIO-I and sarcoma 180. It was shown that the antileukemic activity of DFR and rubomycin with respect to hemocytoblastosis La was practically the same. In the experiments with leukemia P-388 DFR was inferior to rubomycin.  相似文献   
37.
Cells of mouse spleen obtained 48 h after foster splenectomy, foster hepatectomy, resection of 2/3 of spleen or 36 h after resection of 2/3 of liver were introduced intravenously into partially hepatectomized (resection of 2/3 or 1/4 of liver) syngeneic recipients. Cells of regenerating spleen sharply inhibited the mitotic activity of cells of the recipient liver following resection of 1/4 of liver 48 h after the operation and introduction of cells. Inhibition proved to be dose-dependent: it became apparent when 30 million cells were introduced, increased at a dose of 60 million cells and remained at the same level at higher doses. Division of hepatocytes after resection of 1/4 of liver was inhibited by spleen cells taken in the donors 36 h after partial hepatectomy. Spleen cells of intact and pseudo-operated donors had no such ability. Introduction of 60 million of cells of the regenerating spleen and of the spleen of partially hepatectomized animals into recipients with resection of 2/3 of liver did not inhibit reliably the division of hepatocytes, thus indicating the dependence of inhibition on the level of suppressors in the organism. Resection of a major part of liver was accompanied by a greater decrease in the activity of endogenous suppressors which could not be recovered by the introduced cells. Inhibition of cell division by suppressors was not organ specific. Suppressors inhibited proliferation in liver irrespective of the site of operation.  相似文献   
38.
Some features of the Bacillus brevis 101 mutant producing the antibiotic gramicidin S are described. The mutant is very close to the initial P+-variant of Bacillus brevis var. G-B by cultural, physiological and biochemical characteristics. The most typical features of Bacillus brevis 101 are high antibiotic activity (up to 2 g/l) and the specific phenotype of the colonies. The phenotypical features of Bacillus brevis 101 are dependent on the conditions of its cultivation. On minimal media rich in organics a change of the culture correlated with a lower antibiotic activity.  相似文献   
39.
The influence of the carbon source on biological activity and morphological properties of the parasporal crystals of Bacillus thuringiensis subsp. kurstaki cultivated on three different media has been studied. Biological activity of delta-endotoxins contained in crystals was tested according to their impact on insects and microorganisms. Variations in carbon sources composition resulted in changes of biological activity and morphology of crystals, caused by alterations in synthesis rate of various delta-endotoxins contained in the crystals. Variations in the content of a certain carbon source (e.g. starch) in the medium produced no effect on the crystals properties, and the content variations of the delta-endotoxins content was proportional to the producer biomass. Control of the antibacterial effect of delta-endotoxins allows a valid evaluation of their biological activity under various growth conditions as well as comparison of the biological potential of entomopathogenic chemicals for plant protection containing delta-endotoxins with different specificity of insecticidal activity.  相似文献   
40.
New alkulidene hydrazones of rubomycin (daunorubicin) with the linear or branched chain of the carbon atoms were studied: rubomycin 13-(hexylidene-2")-hydrazone, rubomycin 13-(heptylidene-3")-hydrazone and rubomycin 13-(4"-methylpentylidene-2")-hydrazone. Alkylidene hydrazones of the formamidine derivatives were also studied: 13:cyclohexylidene hydrazone of 3'-desamino-3'-dimethylformamidine rubomycin and 13-(5"-oxypentyliden-2") hudrazone of 3'-desamino-3'-dimethylformamidine rubomycin. The latter two alkylidene hydrazones were modified twice. It was found that after a single intravenous administration to tumor-free mice the new substance had the same or lower toxicity as compared to that of rubomycin. Antitumor activity of the substances against lymphosarcoma LIO-I was studied comparatively with that of the initial rubomycin. It was shown that the molecule modification at C-13, as well as simultaneous modification at C-13 and the sugar amino group resulted in lowering of the antitumor activity in comparison to that of the starting rubomycin.  相似文献   
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