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101.
Two cases of free-floating left atrial ball thrombi (FLABT) in association with mitral stenosis were observed by transesophageal echocardiography (TEE). Our report describes the relation between body position and thrombi kinetics. Both cases demonstrated similar kinetics. In the supine and right lateral decubitus positions, the thrombi recoiled from and sometimes became entrapped within the mitral valve. In the sitting and left lateral decubitus positions, the thrombi appeared to be nearly fixed and did not contact with the mitral valve. Our results indicate that the latter two positions prevent thrombi disintegration and incarceration into the mitral valve. Finally, TEE is an extremely useful tool for assessing the safest position for individuals with FLABT.  相似文献   
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Arterial and venous thrombi can coexist without preexisting conditions, such as malignant disease, thrombotic predisposition, or arteriovenous shunt. We herein report a case of acute cerebral infarction and pulmonary thromboembolism in the absence of underlying disease. A 71-year-old woman presented with left hemiplegia. On an examination, her oxygen saturation was 91% on ambient air despite the absence of chest symptoms and clear lung fields on a chest radiograph. The patient was finally diagnosed with acute cerebral infarction caused by large artery atherosclerosis and acute pulmonary thromboembolism due to deep vein thrombosis, consequent to immobilization for three days after the onset of cerebral infarction.  相似文献   
104.
In order to determine whether mixed infections of human herpesvirus 6B (HHV-6B) occur in immunocompetent and immunocompromised individuals, we examined the copy numbers of telomeric repeat sequences (TRS) of clinical isolates. In clinical isolates obtained from patients with exanthem subitum caused by primary HHV-6B infection, PCR products with HHV-6B TRS ranging between 400 and 800 bp were amplified. PCR products of various sizes were amplified in four clinical isolates from drug-induced hypersensitivity syndrome (DIHS) patients and 15 isolates from hematopoietic stem cell transplant (HSCT) recipients with HHV-6B reactivation. Based on the sequence analysis of the PCR products, the copy numbers of TRS in DIHS and HSCT patients were between 42 and 82 and 22 and >90, respectively. For two of the HSCT recipients, HHV-6B TRS PCR products of different sizes were detected in several isolates from each patient, which suggests mixed HHV-6B infections. In two of the posttransplant HHV-6B encephalitis patients, the sizes of the TRS nested PCR products amplified from the reactivated virus detected in the central nervous system differed from those of the virus detected in initial isolates from peripheral blood mononuclear cells. Taken together, these results suggest that PCR analysis of TRS copy number is a reliable tool for the discrimination of HHV-6B clinical isolates. Additionally, mixed HHV-6B infections occurred in HSCT recipients, and in some cases, compartmentalization of the HHV-6B strains to the central nervous system versus the blood compartment occurred in posttransplant HHV-6B encephalitis patients.  相似文献   
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The detection of hepatitis C virus (HCV) in blood donors and patients with acute and chronic hepatitis has brought to the fore another virus or viruses which can be transmitted parenterally and induce liver disease. The RNA of a candidate virus designated GB virus C (GBV-C) was determined by the polymerase chain reaction with primers deduced from a helicase-like region in 229 leprous patients in Japan. GBV-C RNA was detected in 12 (5.2%) patients, and HCV RNA in 41 (18%). Three patients were coinfected with GBV-C and HCV. The nine patients infected with GBV-C alone had aminotransferase levels lower than the three patients with the mixed infection or the 38 patients infected with HCV only (P < 0.001). Sequence comparison within 100 base pairs in the helicase-like region suggested that two, three and three patients, respectively, would have been infected with three distinct strains of GBV-C. These results indicate that patients with leprosy are at increased risk for infection not only with HCV, but also with GBV-C, and that the infection with GBV-C alone would not induce hepatic injuries as severe as HCV infection. © 1996 Wiley-Liss, Inc.  相似文献   
107.
The efficient formation of tert-butyl N-chloro-N-sodio-carbamate by the reaction of simple tert-butyl carbamate with sodium hypochlorite pentahydrate (NaOCl·5H2O) would be a practical and green method for the aziridination of α,β-unsaturated carbonyl compounds. The process described herein is transition-metal free, all of the materials are commercially available, the byproducts (NaCl and H2O) are environmentally benign and the reaction is stereoselective. The resulting aziridines are potential precursors of amino acids.

The efficient formation of tert-butyl N-chloro-N-sodio-carbamate by the reaction of simple tert-butyl carbamate with sodium hypochlorite pentahydrate would be a practical and green method for the aziridination of α,β-unsaturated carbonyl compounds.  相似文献   
108.
ObjectiveG protein-coupled receptor 43 (GPR43), a receptor for short-chain fatty acids, plays a role in suppressing tumor growth; however, the detailed underlying mechanism needs to be comprehensively elucidated. In this study, we investigated the role of GPR43 in inhibiting tumor growth using Apc<sup>Min/+</sup>, a murine model of intestinal tumors.Materials and MethodsUsing GPR43<sup>−/−</sup> Apc<sup>Min/+</sup> and GPR43<sup>+/−</sup> Apc<sup>Min/+</sup> mice, the number of tumors was analyzed at the end of the experimental period. Immunohistochemistry, quantitative polymerase chain reaction, and Western blotting were performed to analyze cellular proliferation and proliferation-associated signal pathways.ResultsOur results revealed that GPR43 deficiency resulted in increased tumor numbers in Apc<sup>Min/+</sup> mice. Ki67 was highly expressed in GPR43<sup>−/−</sup> mice (p > 0.05). Increased expression levels of proinflammatory cytokines, including interleukin-6 and tumor necrosis factor-α, and amino acid transporters were not observed in GPR43-deficient mice compared to GPR43-sufficient mice. Furthermore, GPR43-deficient tumor tissues showed enhanced mammalian target of rapamycin-mediated phosphorylated ribosomal protein S6 kinase beta-1 (p > 0.05) and phosphorylated eukaryotic translation initiation factor 4E-binding protein 1 (p > 0.05), but not Akt (protein kinase B) phosphorylation (p = 0.7088).ConclusionCollectively, GPR43 affords protection against tumor growth at least partly through inhibition of the mammalian target of rapamycin complex 1 pathway.  相似文献   
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110.

Summary

Background and objectives

Dialysis patients show “reverse causality” between serum cholesterol and mortality. No previous studies clearly separated the risk of incident cardiovascular disease (CVD) and the risk of death or fatality after such events. We tested a hypothesis that dyslipidemia increases the risk of incident atherosclerotic CVD and that protein energy wasting (PEW) increases the risk of fatality after CVD events in hemodialysis patients.

Design, setting, participants, & measurements

This was an observational cohort study in 45,390 hemodialysis patients without previous history of myocardial infarction (MI), cerebral infarction (CI), or cerebral bleeding (CB) at the end of 2003, extracted from a nationwide dialysis registry in Japan. Outcome measures were new onsets of MI, CI, CB, and death in 1 year.

Results

The incidence rates of MI, CI, and CB were 1.43, 2.53, and 1.01 per 100 person-years, and death rates after these events were 0.23, 0.21, and 0.29 per 100 person-years, respectively. By multivariate logistic regression analysis, incident MI was positively associated with non-HDL cholesterol (non–HDL-C) and inversely with HDL cholesterol (HDL-C). Incident CI was positively associated with non–HDL-C, whereas CB was not significantly associated with these lipid parameters. Among the patients who had new MI, CI, and/or CB, death risk was not associated with HDL-C or non–HDL-C, but with higher age, lower body mass index, and higher C-reactive protein levels.

Conclusions

In this hemodialysis cohort, dyslipidemia was associated with increased risk of incident atherosclerotic CVD, and protein energy wasting/inflammation with increased risk of death after CVD events.  相似文献   
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