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Negative symptoms of schizophrenia, including anhedonia, represent a heavy burden on patients and their relatives. These symptoms are associated with cortical hypodopamynergia and impaired striatal dopamine release in response to reward stimuli. Catechol-O-methyltransferase (COMT) and monoamine oxidase type B (MAO-B) degrade dopamine and affect its neurotransmission. The study determined the association between COMT rs4680 and rs4818, MAO-B rs1799836 and rs6651806 polymorphisms, the severity of negative symptoms, and physical and social anhedonia in schizophrenia. Sex-dependent associations were detected in a research sample of 302 patients with schizophrenia. In female patients with schizophrenia, the presence of the G allele or GG genotype of COMT rs4680 and rs4818, as well as GG haplotype rs4818-rs4680, which were all related to higher COMT activity, was associated with an increase in several dimensions of negative symptoms and anhedonia. In male patients with schizophrenia, carriers of the MAO-B rs1799836 A allele, presumably associated with higher MAO-B activity, had a higher severity of alogia, while carriers of the A allele of the MAO-B rs6651806 had a higher severity of negative symptoms. These findings suggest that higher dopamine degradation, associated with COMT and MAO-B genetic variants, is associated with a sex-specific increase in the severity of negative symptoms in schizophrenia patients.  相似文献   
104.
Changes in various indices of lipid components of dried doughnut mixtures during their joint or separate 3-month storage were studied. Methyl oleate oxidation model was used to determine the prooxidant properties of the initial mixture. The antioxidant activity, inhibition of oxidation, and inhibitory properties of lipids were shown to be enhanced during storage. The composition of phospholipids varied considerably due to changes in the degree of unsaturation of lipids in the mixture during storage. Joint storage of components resulted in greater stability and better preservation of lipid components (as compared to their separate storage).  相似文献   
105.
Identifying the processes that drive changes in the abundance and distribution of natural populations is a central theme in ecology and evolution. Many species of marine mammals have experienced dramatic changes in abundance and distribution due to climatic fluctuations and anthropogenic impacts. However, thanks to conservation efforts, some of these species have shown remarkable population recovery and are now recolonizing their former ranges. Here, we use zooarchaeological, demographic and genetic data to examine processes of colonization, local extinction and recolonization of the two northern European grey seal subspecies inhabiting the Baltic Sea and North Sea. The zooarchaeological and genetic data suggest that the two subspecies diverged shortly after the formation of the Baltic Sea approximately 4200 years bp , probably through a gradual shift to different breeding habitats and phenologies. By comparing genetic data from 19th century pre‐extinction material with that from seals currently recolonizing their past range, we observed a marked spatiotemporal shift in subspecies boundaries, with increasing encroachment of North Sea seals on areas previously occupied by the Baltic Sea subspecies. Further, both demographic and genetic data indicate that the two subspecies have begun to overlap geographically and are hybridizing in a narrow contact zone. Our findings provide new insights into the processes of colonization, extinction and recolonization and have important implications for the management of grey seals across northern Europe.  相似文献   
106.
The use of factor sera permitting the differentiation of the variants, described in earlier. works, among the flagellar antigens of E. coli, formally denoted as H2, H4, H7, H10 and H34 in accordance with their official nomenclature, has made it possible to reveal that each of these variants is widely spread among E. coli and occurs in bacteria of different O-groups. Besides, this study has shown the possibility of subdividing a number of formal H: O types into 2 or more serovars on the basis of differences in the factor composition of their antigens. The results obtained in this study suggest that in the process of the evolution of E. coli H-antigen variants differing in their factor composition have been formed as independent varieties; therefore, these variants do not reflect the features characteristic of individual strains, but constitute one of the diagnostic signs of serological classification, i. e. the differentiation of the species into various serovars.  相似文献   
107.
The aqueous solutions of Bashkir floral honey of wild and domesticated bees were studied with high-resolution 1H and 13C NMR and nuclear magnetic relaxation. NMR was shown to provide only qualitative data on the composition of the studied honey samples. Data on the composition of the minor components (amino acids), as well as the mobility of water protons in honey, indicate that the distinctions between honey from wild and domesticated bees are due to both the honey composition and the difference in the interactions of components with one another and with water.  相似文献   
108.
The expression of membrane hetero-organic antigens of kidney origin, associated with the rat hepatomas in primary culture of intact adult rat hepatocytes, was investigated by means of the indirect immunofluorescence method using a specific immune serum. These antigens were observed on the membrane of some hepatocytes after their contact with nonhistone chromosomal proteins (NHCP), which were obtained from the kidney of intact rats from cells of hepatoma 27 and Zajdela hepatoma, or from the carcinogenic liver after a single diethylnitrosamine injection. Negative results were obtained after the incubation of hepatocytes in the medium lacking some of NHCP, or in that with NHCP obtained from the liver of intact rats.  相似文献   
109.
It is found that hexenal and sodium thiopental in vitro produced a two-fold increase of frequency of chromosome aberrations as compared with the control and this effect was not dose-dependent. The anesthetics under study affected in vitro 3H-thymidine incorporation into DNA of lymphocytes, and a ten-fold hexenal dose intensified 3H-thymidine incorporation. The frequency of chromosome aberrations in vivo was at the level of the spontaneous mutation after use of sodium thiopental and slightly increased hexenal.  相似文献   
110.
Research on B cells has shown that CD40 activation improves their antigen presentation capacity. When stimulated with interleukin-4 and CD40 ligand (CD40L), human B cells can be expanded without difficulties from small amounts of peripheral blood within 14 days to very large amounts of highly-pure CD40-B cells (>109 cells per patient) from healthy donors as well as cancer patients1-4. CD40-B cells express important lymph node homing molecules and can attract T cells in vitro5. Furthermore they efficiently take up, process and present antigens to T cells6,7. CD40-B cells were shown to not only prime naíve, but also expand memory T cells8,9. Therefore CD40-activated B cells (CD40-B cells) have been studied as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cell-based immunotherapy1,5,10. In order to further study whether CD40-B cells induce effective T cell responses in vivo and to study the underlying mechanism we established a cell culture system for the generation of murine CD40-activated B cells. Using splenocytes or purified B cells from C57BL/6 mice for CD40-activation, optimal conditions were identified as follows: Starting from splenocytes of C57BL/6 mice (haplotype H-2b) lymphocytes are purified by density gradient centrifugation and co-cultured with HeLa cells expressing recombinant murine CD40 ligand (tmuCD40L HeLa)11. Cells are recultured every 3-4 days and key components such as CD40L, interleukin-4, -Mercaptoethanol and cyclosporin A are replenished. In this protocol we demonstrate how to obtain fully activated murine CD40-B cells (mCD40B) with similar APC-phenotype to human CD40-B cells (Fig 1a,b). CD40-stimulation leads to a rapid outgrowth and expansion of highly pure (>90%) CD19+ B cells within 14 days of cell culture (Fig 1c,d). To avoid contamination with non-transfected cells, expression of the murine CD40 ligand on the transfectants has to be controlled regularly (Fig 2). Murine CD40-activated B cells can be used to study B-cell activation and differentiation as well as to investigate their potential to function as APC in vitro and in vivo. Moreover, they represent a promising tool for establishing therapeutic or preventive vaccination against tumors and will help to answer questions regarding safety and immunogenicity of this approach12.Download video file.(141M, mp4)  相似文献   
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