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31.
Protective effect of immunization with heat shock protein (HSP) against bacterial and viral infections in mice was studied. Recombinant HSP 70 kDa of Mycobacterium tuberculosis contaminated with lypopolysaccharide (0.185 mcg/ml) was used for experiments. One intraperitoneal injection of 100 or 400 mcg of HSP induced rapid protection against intraperitoneal challen e with 125 LD50 of Salmonella typhimurium (on 3rd-6th day) and against intranasal challenge with 10 LD50 of avirulent for humans avian influenza virus H5N2 (A/ mallard/Pennsylvania/10218/84) (on 5th-8th day). Three daily injections with 10 mcg of HSP induced rapid, significant and long-term protection against S. typhimurium. Immunization with HSP protected 100% of mice during 3 days after the challenge, 50% of immunized animals survived during 21 days (duration of the study). All nonimmunized mice died on 6th day.  相似文献   
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The influence of the submerged plants Ceratophyllum demersum L. and Elodea canadensis Michx. and the floating plant Hydrocharis morsus-ranae L. on the species composition and quantitative parameters of a zooplankton community was studied experimentally. Among submerged vegetation, the development of the predaceous calanid Heterocope saliens Lilljeborg was suppressed. An increase in the number of zooplankter species was observed in all experimental ecosystems with hydrophytes. The species similarity of zooplankton was higher between communities with plants of the same ecological group than with plants of different groups. The highest average zooplankton biomass, as determined by the abundance of Daphnia longispina O.F. Müller and Simocephalus vetulus (O.F. Müller), was observed in experiments with Elodea. The highest average abundance over the experimental period was recorded among Ceratophyllum, where the abundance of Rotifera, chydorids, and copepods common in hydrophyte beds was higher than in other versions of the experiment.  相似文献   
33.
Zooplankton community transformation in response to soft water acidification was studied in two experimental series using the microcosm method. The dynamics of total abundance, changes in the proportions of the main zooplankton groups, stability of the dominant complex, and species diversity were evaluated. Zooplankton population proved to decrease at all studied low pH (5–6, 4–5, and 3–4) within the first two weeks relative to the control. At water pH 5–6, either Rotifera-Copepoda or Cladocera-Copepoda zooplankton complex was established depending on the initial community composition; while at pH 4–5, Copepoda predominated in the established zooplankton community. The community edificator species was replaced at pH 4–5. The lowest diversity index was also observed at this pH (1.0–1.5 bit/ind.). In addition, the proportion and absolute population of copepod nauplii and cladoceran Scapholeberis mucronata increased at low pH. A decrease in water pH to 3–4 proved to be disruptive for the zooplankton community.Translated from Izvestiya Akademii Nauk, Seriya Biologicheskaya, No. 1, 2005, pp. 100–108.Original Russian Text Copyright © 2005 by Kurbatova.  相似文献   
34.
Influence of immunomodulator of bacterial origin - purified staphylococcal toxoid (PST) - on the synthesisof proinlammatory (IL-1beta, IL-6, TNFalpha, IFN-gamma) and anti-inflammatory (IL- 10) cytokines, as well as cytokines directing the immune response to Th1 (IL-12) or Th2 (IL-4) type was studied in mice. Serum cytokines levels as well as levels of cytokines produced by splenocytes spontaneously or after stimulation by phytohemagglutinin were measured 4 and 24 hours after inoculation of PST. It was shown that PST in wide spectrum of doses (15; 1.5; 0.15 BU per mouse) was able to enhance or suppress synthesis of cytokines. Effect was nonlinear and its direction was depended from cytokine, time interval passed before obtaining the sample and dose of PST. For example, 15 BU of PST enhanced whereas 0.15 BU of PST suppressed the IL-6 production 4 hours after inoculation. Decrease of IL-6 level in serum 24 hours after inoculation of PST was detected. Synthesis of several serum interleukins (IL-2, IL-10) did not changed 4 and 24 hours after inoculation irrespective from dose of PST. It was demonstrated that modulation of humoral immune response in vivo induced by PST did not associated with modulation of cytokine profile. For example, increase of number of cells secreting antibodies to sheep erythrocytes was registered both during increased synthesis of cytokines (4 hours, IL-1beta, IL-6, IL-12) and during period of its depression (IL-6, TNF-alpha, IFN-gamma), as well as during stable production of cytokines (IL-1beta, IL-6, IFN-gamma).  相似文献   
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The results of some investigations recently fulfilled in the framework of population-genetics approach to the problem of adaptive norm in human populations are summarized in this review. The main items considered are: methods of identification of morphologically "average" phenotypes, the role of stabilizing selection in maintaining the population adaptive norm, the problem of joint variation of monogenic and polygenic traits ant its relevance to "norm" and pathology. The significance of the concept of adaptive norm for preventive medicine and genetic monitoring is discussed.  相似文献   
38.
Hereditary variation of 5 immunological systems coded by 8 loci was compared in 148 couples and 100 women with repeated spontaneous abortions in anamnesis (experimental group) and 141 couples and 100 women with normal fertility (control group). Marked differences in distributions of genotypes and frequencies of 3 systems (MNSs, Rhesus, Duffy) and frequency of AB0-incompatible couples were found between control and experimental groups. An average value of observed heterozygosity in experimental group was lower, as compared to the expected value. Possible influence of immunological factors on recurrent fetal wastage is discussed.  相似文献   
39.
Distributions of two metrical characters-the weight and the body length at birth are considered in several groups of healthy, diseased and dead newborns and infants. Significant differences in statistical parameters of these distributions (mean, standard deviation, skewness and kurtosis) are demonstrated for normal and malformated children. The increased number of children with minimal deviations from the mean values of characters (adaptive norm) is observed among healthy newborns, while in groups of diseased and dead children the frequency of individuals with extreme (especially low) values is increased. The principle of classification of individuals based simultaneously on two characteris is suggested and the problem of "average phenotype" classification by the number of characters is discussed.  相似文献   
40.
The study of substrate specificity and activity of proteolytic enzymes secreted by K. pneumoniae strains with different virulence was carried out. The strains were cultivated in a liquid semi-synthetic medium. The biomass was inactivated, and the supernatant fluid was separated from microbial cells by centrifuging. In the supernatant thus obtained and in the fractions isolated by gel filtration with the subsequent purification on DEAE Sepharose elastase-like, trypsin-like and chemotrypsin-like proteolytic activity was determined. In K. pneumoniae strains with different virulence only a single proteolytic enzyme--elastase with a mol. wt. of 21 kD--was detected. The protease activity of the supernatant culture fluid did not depend on the virulence of the strain and was equal to 5,416-7,476 I.U./ml. The activity of the purified enzyme was 100% of the elastase-like activity of the supernatant culture fluid. The most virulent K. pneumoniae strain K2, whose LD50 for white mice was less than 10 microbial cells, was characterized by lower elastase-like activity. The absence of correlation between protease activity and K. pneumoniae virulence may be explained by the fact that surface glycoproteins of eukaryotic cells are glycosilated and thus slightly accessible for proteases.  相似文献   
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