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141.
142.
Generally, major histocompatibility complex (MHC) class I presentation of peptide antigens only occur for proteins' which are actively synthesized and processed intracellularly, so that immunization with a cytotoxic T lymphocyte (CTL) target peptide does not usually elicit effective CTL responses. In the present study, we explored the use of epitope peptides by in vivo electroporation to introduce directly into the cytoplasm for the vaccine elicitation of virus-specific CTLs in a mouse system. BALB/c mice were immunized with human immunodeficiency virus (HIV) env (P18, residues 311-320) or hepatitis C virus (HCV) NS5 (P17, residues 2423-2434) with or without electric pulses. Effector cells against peptide-labeled target cells were elicited in mice immunized with peptides with electric administration but not without electric administration. Moreover, cytolytic activities of CTL against peptide-labeled target cells were enhanced by the addition of plasmid having the immunostimulatory sequence (ISS) or cDNA of the B7-1 molecule in electric administration of peptides. The results of the present study suggest that a peptide vaccine against a virus using electric administration is effective in eliciting virus specific CTLs.  相似文献   
143.
The effects of chlorpheniramine and epinastine on dihydrocodeine were examined in mice. Orally administered dihydrocodeine (3-30 mg/kg) dose-dependently inhibited the number of capsaicin-induced coughs. The dose-dependent antitussive effects of dihydrocodeine were enhanced by each corresponding dose of chlorpheniramine or epinastine delivered at a ratio generally similar to that found in over-the-counter antitussive preparations (dihydrocodeine:histamine H1 antagonist = 3:1). The ED50 value of dihydrocodeine in combination with chlorpheniramine was nearly the same as that for dihydrocodeine in combination with epinastine. On the other hand, while combination treatment with dihydrocodeine (3 mg/kg i.p.) and chlorpheniramine (1 mg/kg s.c.) significantly potentiated place preference, no potentiation was observed with the combination of dihydrocodeine (3 mg/kg i.p.) and epinastine (1 mg/kg s.c.). These results suggest that epinastine may be a useful constituent opioid-containing antitussive preparation that would not enhance the potential for psychological dependence.  相似文献   
144.
The current study reports active glycosidases in the lens of ICR/f rats, which generate a hereditary cataract approximately 90 d after birth, and the variation in enzyme activity with cataract progression. Seven active glycosidases, beta-D-galactosidase, alpha-D-glucosidase, beta-D-glucosidase, beta-D-glucuronidase, beta-D-galactosaminidase, beta-D-glucosaminidase and alpha-D-mannosidase, were detected in ICR/f rat lenses. Of these, beta-D-glucuronidase and beta-D-galactosidase showed a tendency to increase in activity with the cataract progression. Furthermore, beta-D-glucosidase and alpha-D-mannosidase showed a transitory increase in activity at the time of cataract formation. This result suggests that several glycosidases in the lens may be involved in the hereditary cataract formation. The optimal pH and temperature of the seven active glycosidases in rat lenses were also measured in this study.  相似文献   
145.
The antitumor effects of a polyamine biosynthetic pathway inhibitor methylglyoxal bis(cyclopentylamidinohydrazone) (MGBCP) on the human hepatocellular carcinoma SK-HEP-1 cell line have been investigated. The growth of these cultured hepatocellular carcinoma cells was inhibited by MGBCP in a dose-dependent manner. Spermidine and spermine levels were dose-dependently depressed, and morphological changes due to programmed cell death (apoptosis) were observed in these MGBCP-treated hepatocellular carcinoma cells. These results suggest that in addition to reducing the growth rates, MGBCP can induce apoptotic cell death in this human hepatocellular carcinoma cell line.  相似文献   
146.
We report a rare complication of a secondary malignant solid tumor in two patients with non-Hodgkin's malignant lymphoma who developed lung adenocarcinoma after treatments with combination chemotherapies. The first was a case of primary malignant lymphoma of the cervical spinal cord which had been previously treated with radiation to the spinal lesion and combination chemotherapies and entered complete remission. The patient was further treated for relapse with autologous bone marrow transplantation preconditioned with high-dose chemotherapy. Lung adenocarcinoma developed 5.5 years after the initial diagnosis. The second case of malignant lymphoma of lymph nodes did not respond to conventional combination chemotherapies and did not enter remission. Lung adenocarcinoma developed 1 year after the initial diagnosis. The two patients died of lung carcinoma. The clinical profiles of these cases are presented and the causal relationship of primary malignant neoplasms to the second malignant neoplasms is discussed.  相似文献   
147.
Mechanisms of cell adhesion and migration]   总被引:3,自引:0,他引:3  
In order to understand the molecular mechanisms underlying cancer metastasis, it is important to clarify the mechanisms of cell adhesion and cell migration. When epithelial cells start to migrate, cell-cell junctions are first disrupted. During migration, membrane protrusions, such as lamellipodia and filopodia, are observed externally at the cell front, and retraction at the cell rear. In addition, dynamic reorganization of the actin cytoskeleton, such as disassembly and reassembly of stress fibers at cell-cell and cell-matrix junctions and membrane protrusions, is observed internally. Our experiments have demonstrated that the Rho and Rab family small G proteins coordinately regulate cell adhesion and migration of cultured MDCK cells. The Rho family consists of the Rho, Rac, and Cdc 42 subfamilies. The Rho subfamily regulates stress fiber formation, and integrin-based cell matrix adhesion. Furthermore, the Rac and Cdc 42 subfamilies regulate lamellipodia and filopodia formation, respectively, as well as cadherin-based cell-cell adhesion. The detailed modes of action of these small G proteins remain to be clarified; however, it is known that these proteins regulate cell adhesion and migration through reorganization of the actin cytoskeleton. The Rab family has over thirty members. We have found that some Rab family members are involved in HGF- or phorbol ester-induced endocytosis and exocytosis (recycling) of adhesion molecules such as integrin and cadherin. Endocytosis and exocytosis of these adhesion molecules are accompanied by disassembly and reassembly of the actin cytoskeleton, respectively, in a well coordinated manner. Thus, we propose the cooperative roles of the Rho and Rab families in cell adhesion and migration.  相似文献   
148.
Kikyo M  Tanaka K  Kamei T  Ozaki K  Fujiwara T  Inoue E  Takita Y  Ohya Y  Takai Y 《Oncogene》1999,18(50):7046-7054
Proteins containing formin homology domains, FH1 and FH2, are involved in cytokinesis or establishment of cell polarity in a variety of organisms. Bni1p and Bnr1p are FH proteins and potential targets of the Rho family small GTP-binding proteins in S. cerevisiae. We have shown that Bnr1p is localized at the bud neck to interact with Hof1p, involved in cytokinesis. We report here that the overexpression of BNR1 causes a cytokinesis deficiency which is similar to the phenotypes of the septin mutants, including cdc3, cdc10, cdc11, and cdc12. The region required for the septin mutant phenotypes was mapped to Bnr1p (35-500), which coincided with the region required for the bud-neck localization. To further isolate a gene interacting with BNI1 or BNR1, a multicopy suppressor of the bni1 bnr1 mutant was isolated. This gene encoded Smy1p, a kinesin-related protein. Bnr1p, but not Bni1p, directly interacted with the C-terminal region of Smy1p. The Smy1p-interacting region of Bnr1p was mapped to a region containing the FH2 domain. Bnr1p also directly interacted with Bud6p, a novel actin-binding protein. Bnr1p is thus a multifunctional protein which interacts with the septin system, a microtubule-dependent motor protein, and the actin system, to regulate cytoskeletal functions in S. cerevisiae.  相似文献   
149.
The effect of glibenclamide, an ATP-sensitive K(+) channel blocker, on the anti-tussive effect of moguisteine and of pinacidil, an ATP-sensitive K(+) channel opener in guinea pigs was studied. Pinacidil (1 and 5 mg/kg, subcutaneous (s.c.)) dose-dependently reduced the number of coughs. The anti-tussive effect of pinacidil was significantly and dose-dependently antagonized by pre-treatment with glibenclamide (3 and 10 mg/kg, i.p.). Moguisteine (1 and 5 mg/kg, s.c.) dose-dependently reduced the number of coughs. The anti-tussive effect of moguisteine was also reduced by pre-treatment with glibenclamide, in a dose-dependent manner. However, pre-treatment with glibenclamide had no effect on the anti-tussive effects of dihydrocodeine and dextromethorphan. Glibenclamide (10 mg/kg, i.p.), by itself, had no significant effect on the number of coughs. These results suggest that pinacidil and moguisteine may exert their anti-tussive effects through the activation of ATP-sensitive K(+) channels. Furthermore, it is possible that ATP-sensitive K(+) channels may be involved in the anti-tussive effect of peripherally acting non-narcotic anti-tussive drugs.  相似文献   
150.
Tannic acid was cultured together with tumor cells that had originated from human malignant tumors (HCT-15 & AGS). Significant suppression of tumor growth was observed. The 50% suppression was observed at the concentration between 50 micrograms/ml and 12.5 micrograms/ml. When tannic acid was injected into HCT-15 cells by electroporation at 1180 mu p and 200 ohm, the suppression rate was 34.3% at the concentration of 50 micrograms/ml in HBS solution. The suppression rate of cells only in contact with tannic acid solution for one hour under the same conditions as used for electroporation, was 26.1%. Histographic findings suggested that tannic acid almost completely blocked the S phase of the cell cycle.  相似文献   
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