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121.
The influence of staphylococcal enterotoxin of type A (SEA) and enterobacterial lipopolysaccharide (LPS) on the production of tumor necrosis factor alpha (TNF alpha), gamma-interferon and active forms of oxygen by mouse peritoneal cells was studied. Both SEA and LPS, when injected to animals, produced stimulating influence on the oxygen metabolism of phagocytizing cells. The highest toxic doses of LPS induced the maximal generation of oxygen radicals. Under the conditions of the development of lethal toxic shock, i.e. after the combined injection of SEA and LPS, the synergic activation of oxygen metabolism was observed, which was also manifested by the pronounced production of TNF alpha and the increased synthesis of gamma-interferon.  相似文献   
122.
In activity the comparative analysis of metabolic effects delta--sleep inducing peptide (DSIP) in tissues and erythrocytes of intact rats and under cold stress is conducted. The regulation effect of DSIP in attitude of free radical processes will be realised through modulation the prooxidant--antioxidant balance: both for intact animal, and at stress. Exogenous DSIP increases the antioxidant system activity in tissues of brain, liver and blood in standard conditions and under cold stress. The anti-stress effect of DSIP is directed as on increase of power endogenic enzymatic antioxidant system activity, specially glutathione peroxidase activity, and not enzymatic of antioxidant protection. The DSIP renders different influence on activity of prooxidant enzymes: for intact animal boosts the myeloperoxidase activity in blood neutrophils, not rendering essential influencing on the xanthine oxidase activity in tissues of brain, liver and activates the myeloperoxidase activity, depresses the xanthine oxidase activity for rats at stress. The membranotropic effect of DSIP in the norm and under stress is connected to increase of stability of protein--lipid interplays. The membranostabilizing effect of DSIP in conditions of stress is characterized decrease of polarity of lipid phase and negative surface charge of erythrocyte membranes, modified in course of lipid peroxidation.  相似文献   
123.
A high level of shigellosis morbidity requires new approaches to the control of bacterial dysentery. According to modern concepts, the outbreaks of Shigella infections are linked both with less intensive epidemic control measures and the objective cyclic character of the epidemic process. In this connection great importance is attached to the development of vaccines for the immunization of high risk groups in territories with unfavorable epidemic conditions and in zones of military conflicts, as well as children of school and pre-school age, who mostly determine seasonal rises of shigellosis morbidity. In this article the data describing new approaches to the creation of new live enteric vaccines on the basis of the knowledge of the genetic control of microbial pathogenicity and the regulation of its expression are presented. Attenuated Shigella mutants, created by different authors and having good prospects to be used for the development of vaccines, are characterized.  相似文献   
124.
A complex of clinical and laboratory examinations of patients with bacterial chronic prostatitis was carried out. The patients were divided into two groups: 55 patients treated by the method of immunotherapy and 20 patients (controls) undergoing basic therapy. Immunotherapy was carried out with the use of polycomponent vaccine VP-4 containing Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris and Escherichia coli antigens. Vaccinal therapy was indicated in cases with infection focus associated with opportunistic bacteria, a prolonged torpid course of prostatitis and when different schemes of etiotropic therapy proved to be ineffective. The vaccine was introduced in 4 or 5 subcutaneous injections at an interval of 5-7 days. The study revealed that in cases of chronic prostatitis accompanied by microecological and immune disturbances the use of complex therapy allowed to achieve good clinical and laboratory results in 91% of the patients. In the patients undergoing immunotherapy the elimination of opportunistic bacteria from the urogenital tract and the restoration of affected microflora occurred.  相似文献   
125.
The specific activity of serine, metal dependent and thiolic Ig proteases in the coprofiltrates of children with manifestations of intestinal dysbacteriosis was determined by the enzyme immunoassay. 56 children with pronounced symptoms of intestinal disorders (37 children aged up to 1 year and 19 children over 1 year) were examined. A group of 25 clinically healthy children was used as control. Simultaneously with protease activity of coprofiltrates, there was detected the level of Ig-degrading activity of the opportunistic bacteria islolates of different taxonomic groups from feces of children with dysbacteriosis of different severity (as determined by the classical bacteriological method). The evaluation of the Ig-proteolytic activity of fecal supernatants, associated with the presence of serine, metal-dependent and thiolic proteases in the intestine, as well as detection of such proteases in microbial isolates, seems to be highly important for the diagnosis of intestinal disorders in children and is recommended for screening of intestinal dysbacteriosis.  相似文献   
126.
The review deals with the molecular aspects of the interaction of bacterial lipopolysaccharides (LPS, with the macroorganism: the sources of LPS in the organism, its detoxication, regulation disturbances in pathology (septic shock). Special attention is drawn to the complex functioning of cytokines in the development of the inflammatory process both at the initial stage, characterized by the initiation of the cytokine cascade and at the final stage resulting in convalescence or the development of pathology. The most promising trends of research in this field are discussed.  相似文献   
127.
Data are presented on the life-cycles and the postembryonal development of four species of Branchiopodataenia Bondarenko & Kontrimavichus, 2004, B. anaticapicirra Bondarenko & Kontrimavichus, 2004, B. arctowskii (Jarecka & Ostas, 1984), B. haldemani (Schiller, 1951) and B. pacifica (Spassky & Jurpalova, 1968), which are specific parasites of gulls. The investigation was carried out in Chukotka (Chaun Bay) between 1971 and 1981 under natural and experimental conditions. Branchiopod crustaceans were exclusive natural and experimental intermediate hosts of all of the species studied; this fact provided additional evidence for the erection of Branchiopodataenia. The metacestodes exhibit a pattern of postembryonal development and a typical larval form, termed a 'cercocyst', which is a modification of a cysticercoid. This modification of the metacestode does not occur in species of Wardium Mayhew, 1925, the genus with which species of Branchiopodataenia had previously been affiliated.  相似文献   
128.

Background  

Although direct infiltration of papillary carcinoma of thyroid to larynx, trachea and esophagus is well recognized, lymphatic and vascular metastases to larynx and hypopharynx have rarely been reported.  相似文献   
129.
The presence of fragments of genomes hlyA, hlyB, papAH, papC, sfaG, sfaA and kps MT, associated with the pathogenicity islands of Escherichia coli, in clinical strains of other genera of the family Enterobacteriaceae, has been experimentally evaluated with the use of PCR. The presence of DNA fragments specific to the known genes of the pathogenicity clusters of E. coli in representatives of the genera Citrobacter, Enterobacter, Hafnia, Klebsiella, Morganella, Proteus, Providencia, Serratia and Yersinia of rarely occurring groups has been established. In Enterobacteriaceae cultures isolated from the intestine amplicons homologous to hlyB were detected significantly less frequently than among strains of nonintestinal origin. In Enterobacteriaceae strains isolated in respiratory pathology amplicons of the pili gene (sfaG) were detected significantly more frequently than in collection cultures. The total evaluation of the detection rate of the genes of pathogenicity islands among Enterobacteriaceae clinical strains under study in comparison with E. coli showed that they occurred significantly less frequently. Klebsiella spp. were found to differ most essentially from E. coli as regards the occurrence of fragments of the genes of pathogenicity islands. The conclusion was made on the high probability of genetic exchange in DNA fragments between different species of bacteria with corresponding changes in their pathogenicity.  相似文献   
130.
The characterization of known Salmonella vaccine strains and different attenuated mutants used for developing new vaccines is presented. The use of attenuated Salmonella strains as vaccine vector for the supply of heterologous antigens opens prospects for the creation of effective and commonly available vaccines which approximate the "ideal" vaccine in their qualitative characteristics. The possibility of the genetic modification of attenuated strains permits their targeted reconstruction, considering the specific features of the formation of immune response to the definite heterologous antigen supplied to the body by the bacterial vector.  相似文献   
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