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91.
In vivo gene gun-mediated DNA delivery into rodent brain tissue   总被引:1,自引:0,他引:1  
Various types of gene transfer into live tissues have been tried. However, in vivo gene transfer into brain tissue or neuronal cells without virus vector has required a great effort. Particle-mediated gene transfer into live brain tissue was thought to be impossible because of its fragility and the mechanical problem of a previous type of gene gun. In addition, particle-mediated DNA transfer into monolayer-cultured cells without mechanical damage has been difficult. We successfully transferred DNA into rodent live brain tissue and also into monolayer-cultured cells without mechanical damage by using a new type of gene gun and also confirmed gene expression in the brain. This new method represents another variation of gene transfer into the brain.  相似文献   
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Genetic polyymorphisms that result in three amino acid changes in FcepsilonRI beta chain (Ile(181)-->Leu, Val(183)-->Leu, and Glu(237)-->Gly) have been identified as candidates that associate with allergic disorders such as atopy and asthma. To elucidate the biological significance of these polymorphisms in regulating the expression and function of FcepsilonRI, we generated four types of transfectants that express wild-type or mutant mouse beta chains corresponding to these human variants by retrovirus-mediated gene transfer into beta chain-deficient mouse-derived mast cells. No significant functional differences between the wild-type beta chain transfectant and any of the mutant beta chain transfectants were observed in beta-hexosaminidase release, intracellular calcium mobilization, or cytokine and leukotriene C(4) production in response to FcepsilonRI crosslinking. Our results suggest that these polymorphisms in FcepsilonRI beta chain do not affect FcepsilonRI-mediated mast cell activation at least in our mouse in vitro system.  相似文献   
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Proteoglycans were extracted with 4 M guanidine–HCl from the zone of maturing chondrocytes, the site of endochondral ossification of growing antlers of wapiti (Cervus elaphus). Proteoglycans were isolated by DEAE-Sephacel chromatography and separated by Sepharose CL-4B chromatography into three fractions. Fraction I contained a high molecular mass (>1000 kDa) chondroitin sulfate proteoglycan capable of interacting with hyaluronic acid. Its amino acid composition resembled that of the cartilage proteoglycan, aggrecan. Fraction II contained proteoglycans with intermediate molecular weight which were recognized by monoclonal antibodies specific to chondroitin sulfate and keratan sulfate. Fraction III contained a low molecular mass (<160 kDa) proteoglycan, decorin, with a glucuronate-rich glycosaminoglycan chain.  相似文献   
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We have previously identified 17 biomarker genes which were upregulated by whole virion influenza vaccines, and reported that gene expression profiles of these biomarker genes had a good correlation with conventional animal safety tests checking body weight and leukocyte counts. In this study, we have shown that conventional animal tests showed varied and no dose-dependent results in serially diluted bulk materials of influenza HA vaccines. In contrast, dose dependency was clearly shown in the expression profiles of biomarker genes, demonstrating higher sensitivity of gene expression analysis than the current animal safety tests of influenza vaccines. The introduction of branched DNA based-concurrent expression analysis could simplify the complexity of multiple gene expression approach, and could shorten the test period from 7 days to 3 days. Furthermore, upregulation of 10 genes, Zbp1, Mx2, Irf7, Lgals9, Ifi47, Tapbp, Timp1, Trafd1, Psmb9, and Tap2, was seen upon virosomal-adjuvanted vaccine treatment, indicating that these biomarkers could be useful for the safety control of virosomal-adjuvanted vaccines. In summary, profiling biomarker gene expression could be a useful, rapid, and highly sensitive method of animal safety testing compared with conventional methods, and could be used to evaluate the safety of various types of influenza vaccines, including adjuvanted vaccine.  相似文献   
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The gap junction proteins connexin32 (Cx32), Cx37, Cx40, and Cx43 are expressed in endothelial cells, and regulate vascular functions involving inflammation, vasculogenesis and vascular remodeling. Aberrant Cxs expression promotes the development of atherosclerosis which is modulated by angiogenesis; however the role played by endothelial Cxs in angiogenesis remains unclear. In this study, we determined the effects of endothelial Cxs, particularly Cx32, on angiogenesis. EA.hy926 cells that had been transfected to overexpress Cx32 significantly increased capillary length and the number on branches compared to Cx-transfectant cells over-expressing Cx37, Cx40, and Cx43 or mock-treated cells. Treatment via intracellular transfer of anti-Cx32 antibody suppressed tube formation of human umbilical vein endothelial cells (HUVECs) compared to controls. In vitro wound healing assays revealed that Cx32-transfectant cells significantly increased the repaired area while anti-Cx32 antibody-treated HUVECs reduced it. Ex vivo aorta ring assays and in vivo matrigel plaque assays showed that Cx32-deficient mice impaired both vascular sprouting from the aorta and cell migration into the implanted matrigel. Therefore endothelial Cx32 facilitates tube formation, wound healing, vascular sprouting, and cell migration. Our results suggest that endothelial Cx32 positively regulates angiogenesis by enhancing endothelial cell tube formation and cell migration.  相似文献   
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Hemidesmosomes are cell-to-matrix adhesion complexes anchoring keratinocytes to basement membranes. For the first time, we present a method to prepare a fraction from human cultured cells that are highly enriched in hemidesmosomal proteins. Using DJM-1 cells derived from human squamous cell carcinoma, accumulation of hemidesmosomes was observed when these cells were cultured for more than 10 days in a commercial serum-free medium without supplemental calcium. Electron microscopy demonstrated that numerous electron-dense adhesion structures were present along the basal cell membranes of DJM-1 cells cultured under the aforementioned conditions. After removing cellular materials using an ammonia solution, hemidesmosomal proteins and deposited extracellular matrix were collected and separated by electrophoresis. There were eight major polypeptides, which were determined to be plectin, BP230, BP180, integrin α6 and β4 subunits, and laminin-332 by immunoblotting and mass spectrometry. Therefore, we designated this preparation as a hemidesmosome-rich fraction. This fraction contained laminin-332 exclusively in its unprocessed form, which may account for the promotion of laminin deposition, and minimal amounts of Lutheran blood group protein, a nonhemidesmosomal transmembrane protein. This hemidesmosome-rich fraction would be useful not only for biological research on hemidesmosomes but also for developing a serum test for patients with blistering skin diseases.  相似文献   
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A field experiment was conducted to investigate the effects of white clover living mulch on the arbuscular mycorrhizal (AM) fungus colonization of corn roots and the yield of silage corn. The following seven treatments were setup in a field that had been kept bare by rotary tillage from August 2003 to July 2004: two white clover living mulch treatments without phosphorus (P) application, with the white clover shoots clipped and removed or allowed to lie in place before sowing corn; one no-tillage treatment without P application; and four rotary tillage treatments with different P application rates. White clover was broadcasted in the living mulch treatments in August 2004. In June 2005, the white clover shoots in the living mulch treatments were clipped. After tilling the four rotary tillage treatments, corn was sown in all the treatments. The fallow period before sowing corn was 0 month (living mulch treatments) and 22 months (no-tillage and rotary tillage treatments). At knee high stage, the AM fungus colonization of the corn roots and the P concentrations of the corn shoots in both the living mulch treatments were increased relative to those in the other treatments. The yield of corn tended to increase in the no-tillage and rotary tillage treatments with an increase in the P application rate. On the other hand, the yields of corn in the living mulch treatments without the P application were not significantly different from the maximum yield among the no-tillage and rotary tillage treatments. These results suggested that the white clover living mulch increased the yield of corn by facilitating the AM fungus colonization and improving the P nutrition of corn.  相似文献   
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