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991.
Five malignant glioma cell lines (YMG1, 2, 3, 4, and 5) were established from surgical specimens obtained from patients with glioblastoma or anaplastic astrocytoma, and these lines were partially characterized. Three glioma cell lines (YMG1, 3, and 5) were weakly positive for GFAP by Western blot analysis and two cell lines were negative. S‐100 protein was positive in all glioma cell lines. The expression of p53, p16, p15, cyclin‐dependent kinase 4 (CDK4), and EGF receptor (EGFR) proteins was examined by Western blotting. YMG1 and 2 cell lines showed accumulation of p53 protein and loss of p16 and p15 expression. YMG3 and 4 showed accumulation of p53 protein and expression of p16 and p15 proteins. YMG5 revealed weak expression of p53 protein, suggesting wild‐type p53, and loss of p16 and p15 expression. All cell lines expressed various levels of CDK4 protein. YMG1, 2, and 3 showed higher EGFR protein expression and YMG4 and 5 showed lower EGFR expression compared to U251 glioblastoma cells, which express high levels of EGFR. Fluorescence in situ hybridization analysis for EGFR gene expression did not show any amplification in the glioma cell lines. Immunohistochemical studies revealed that the patterns of p53 and EGFR expressions in the original tumor tissues were mostly correlated with those in the malignant glioma cell lines. These results suggest that the characteristics of p53 and EGFR expression in the malignant glioma cell lines were passed over from the original tumor tissues. These newly established malignant glioma cell lines can be used for further analysis of the mechanisms of tumor growth and progression.  相似文献   
992.
A 44-year-old man was transferred to our hospital because of severe congestive heart failure complicated with acute renal failure and hepatic failure. He had been injured in a traffic accident three years before. Echocardiogram demonstrated a large tumor on the anterior wall of right ventricle obstructing RV outflow. Emergent operation was performed with cardiopulmonary bypass. Tumor was too large and invading into RV endocardium partially. RV patch enlargement was performed because it was impossible to resect tumor entirely. CVP was decreased dramatically to 8 cmH2O from 28 cmH2O. Postoperative hemodynamic was stable, but patient died of hepatic failure. Autopsy revealed that tumor was pseudoaneurysm from ascending aorta and ruptured into right ventricle.  相似文献   
993.
To clarify the differences in characteristics between participants and non-participants in the screening program for stomach cancer, life-style and medical histories were compared among 20, 169 subjects who lived in an urban area (Sendai) and a rural area (Wakuya and Tajiri) in Miyagi Prefecture, Japan. All subjects were classified into three groups according to the frequency of participation in the screening program during the last 5 years; i.e., frequent participating group (FPG) for 4 or 5 times, reference group (RG) for 1-3 times and non-participating group (NPG) for 0 times. Subjects in the FPG consumed more milk and green-yellow vegetable whereas those in the NPG consumed less these foods. The age-adjusted proportions of present smokers were higher in the NPG but lower in the FPG significantly. The proportions of subjects who had parental histories of all cancers and stomach cancer and past history of gastro-duodenal ulcer were higher in the FPG and lower in the NPG. To control influences among the variables a stepwise multiple regression analysis was done, and it revealed that smoking and parental history of cancers were strong predictors to explain the frequency of participation.  相似文献   
994.
995.
Three cases with cavitary lesions on the cerebral convexities in twin gestation complicated by a single intrauterine fetal demise were investigated clinicopathologically. They all exhibited profound mental retardation and severe motor disturbance due to rigidospastic tetraplegia. The co-twins were macerated. Neuropathologically, malformed lesions and destructive lesions coexisted in varying degrees according to the time in fetal life, at which insults probably occurred. The cavitary lesions were located bilaterally and symmetrically on the central, parietal and occipital region of the cerebral hemispheres, in some cases, including the frontal region. Case 1 showed an incomplete gyral pattern and porencephaly with polymicrogyria bordering the defect, thus allowing us to date the insult before the 5th fetal month. In case 2, multicystic encephalomalacia was disclosed with cortical dysgenesis exhibiting status marmoratus of the cortex. Case 3 displayed sclerotic cavitary lesions with sclerosis of the insula and a few instances of cortical dysgenesis. Based on the clinical data and pathological findings, the cavitary lesions of case3 may be dated in the third trimester of gestation. Case 2 can be considered to have sustained injuries between the times estimated for cases 1 and 3. As the pathogenesis of the congenital cavitary lesions, several concepts have been proposed: intrauterine DIC (Moore et al. 1969;Romero et al. 1984), vascular disruption (Hoyme et al. 1981;Jung et al. 1984), intrauterine infection such as cytomegalic inclusion disease (Friede et al. 1976), and hypoxia due to CO intoxication of the mother (Bank1 et al. 1967) or other cause. Though the pathological observation of our cases revealed no evidence of intrauterine DIC, renal cortic necrosis, intrauterine infection or occlusion of the intracranial vessels, long-term exposure to the dead twin might have contributed to the lesions of the liveborn co-twin.  相似文献   
996.
Mycophenolate mofetil is currently used instead of azathioprine in clinical transplantation. However, comparative studies for the immunosuppressive potency of anti-metabolites used for organ transplantation have not been well documented. We compared the pharmacological efficacy of mycophenolic acid (MPA), 6-meraputopurine (6-MP), and mizoribine (MZ) for inhibiting purine synthesis of peripheral blood mononuclear cells (PBMCs) in vitro by a mitogen assay procedure. PBMCs were obtained from 18 renal transplant recipients before operation and 18 healthy subjects. The inhibitory efficacy of 6-MP against concanavalin A-induced PBMC blastogenesis exhibited large variations between subjects in both recipients and healthy subjects. In contrast, the pharmacological efficacy of MPA on PBMC blastogenesis showed the smallest inter-individual variation of all the purine synthesis inhibitors examined. Furthermore, the effects of MPA were almost similar in the recipients and healthy subjects. The pharmacological efficacy of MZ against PBMC blastogenesis was weaker than that of the other two agents and the inter-individual variation of MZ IC50 against PBMCs of the patients was larger than that of MZ IC50 against PBMCs of healthy subjects. Reproducible immunosuppressive efficacy of MPA compared with other purinesynthesis inhibitors could be expected from the viewpoint of MPA pharmacodynamics against PBMCs in renal transplantation.  相似文献   
997.
Anti-ras p21 monoclonal antibody (RASK-3) was used for immunoscintigraphy of human cancer cell lines in nude mice. Iodine-125-labeled RASK-3 was injected into nude mice with either human colon cancers (FCC-1 or BM-314) or lung cancer (KNS-62). Clear images were obtained in all three cancers 7 days after the injection of antibody. No localization of 125I-labeled control monoclonal antibody was observed. The ratio of tissue/blood radioactivity and % ID/g in the tumor were significantly higher than other organs by Day 8. The specific localization index examined by 131I-RASK-3 and 125I-control monoclonal antibody was also higher in the tumor than in other tissues. In the in vitro study, binding of RASK-3 to tumor cells increased significantly by treatment of cells with either lysolecithin or periodate-lysine-paraformaldehyde, which confirmed the intracellular localization of ras p21. The mechanism by which anti-ras p21 antibodies accumulate in tumor sites could be the necrotic changes in tumor cells or changes in membrane permeability of non-necrotic cells. These results provide a strong rationale for the utilization of ras p21 as a target antigen in the imaging of a variety of human cancers.  相似文献   
998.
999.
Background The follicle‐associated epithelium (FAE) is specialized in uptake and sampling of luminal antigens and bacteria. We previously showed that stress increased FAE permeability in rats. An increased uptake may alter antigen exposure in Peyer’s patches leading to intestinal disease. The aim of this study was to elucidate mechanisms involved in the acute stress‐induced increase in FAE permeability. Methods Rats were pretreated i.p. with corticotropin‐releasing hormone receptor (CRH‐R) antagonist, neurokinin receptor 1 (NK‐1R) antagonist, atropine, the mast cell stabilizer doxantrazole (DOX), or NaCl, and submitted to 1‐h acute water avoidance stress. FAE tissues were mounted in Ussing chambers for measurements of permeability to 51Cr‐EDTA, horseradish peroxidase (HRP) and chemically killed Escherichia coli K‐12. Further, FAE segments were exposed in vitro in chambers to CRH, substance P (SP), carbachol, and DOX. Neurotransmitter‐ and receptor distribution was studied by immunohistochemistry. Key Results Stress‐induced increases in uptake across FAE of HRP and E. coli were reduced by DOX, CRH‐R antagonist and atropine, whereas the NK‐1R antagonist decreased 51Cr‐EDTA permeability. Exposure to CRH and carbachol increased HRP and E. coli passage, whereas SP increased bacterial and 51Cr‐EDTA permeability. DOX counteracted all of these effects. Immunohistochemistry revealed CRH, acetylcholine, SP, and their receptors on mast cells within the Peyer’s patches, subepithelial dome, and adjacent villi. Conclusions & Inferences Corticotropin‐releasing hormone and acetylcholine signaling affect mainly transcellular permeability while SP seems more selective toward the paracellular pathways. Our findings may be of importance for the understanding of the pathogenesis of stress‐related intestinal disorders.  相似文献   
1000.
Case A 68-year-old woman with family history of fibromatous skinlesions was referred for the evaluation of hypertension. Withdetection of multiple fibromatous skin lesions and caféau lait spots, a diagnosis of von Recklinghausen's disease wasmade. Because  相似文献   
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