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Cyanobacteria can generate molecules hazardous to human health, but production of the known cyanotoxins is taxonomically sporadic. For example, members of a few genera produce hepatotoxic microcystins, whereas production of hepatotoxic nodularins appears to be limited to a single genus. Production of known neurotoxins has also been considered phylogenetically unpredictable. We report here that a single neurotoxin, beta-N-methylamino-L-alanine, may be produced by all known groups of cyanobacteria, including cyanobacterial symbionts and free-living cyanobacteria. The ubiquity of cyanobacteria in terrestrial, as well as freshwater, brackish, and marine environments, suggests a potential for wide-spread human exposure.  相似文献   
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Combination therapy of interferon-2b and ribavirin was prospectively evaluated in 20 patients with chronic replicative hepatitis and persistently normal ALTs. Patients with normal ALTs on three or more occasions within 6 months received interferon-2b 3 MU three times a week with ribavirin 1000–1200 mg everyday for 12 months and had a follow-up of 6 months. HCV genotype 1 was found in 16, and HCV genotype 2 or 3 in 4 patients. No patient experienced an ALT elevation during therapy. Ten of 20 patients (50%) cleared virus at the end of treatment. In an intent-to-treat analysis, a sustained virological response (SR) was achieved in 8 of 20 patients (40%). Nonresponse occurred in 5 patients. Relapse and breakthrough were seen in 2 patients each. Treatment was discontinued in 3 patients due to side effects. Interferon (IFN) ribavirin combination therapy is effective in patients with normal ALTs and appears superior to IFN monotherapy.  相似文献   
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BACKGROUND: To evaluate potential sex differences, this study aimed to investigate blood pressure and lipid control and other risk factors for cardiovascular disease in treated hypertensive (tHT) patients from primary healthcare. DESIGN AND METHODS: This cross-sectional survey of tHT patients was carried out between 2002 and 2005 by 264 primary care physicians from Sweden who consecutively recruited 6537 tHT patients (48% men and 52% women) from medical records. RESULTS: tHT men more often reached the treatment goal for systolic/diastolic blood pressure, less than 140/90 mmHg, than tHT women (30 vs. 26%, P<0.01). Men had lower systolic blood pressure than women, however, women had lower diastolic blood pressure and higher pulse pressure. More tHT women had total cholesterol>or=5.0 mmol/l than corresponding men (75 vs. 64% P<0.001). Men more often had diabetes (25 vs. 20% P<0.001), left ventricular hypertrophy (20 vs. 16% P<0.001), and microalbuminuria (24 vs. 16% P<0.001). Women were more often treated with diuretics (64 vs. 48%) and beta-receptor blockers (54 vs. 51%), and men more often treated with angiotensin-converting enzyme inhibitors (27 vs. 18%), calcium channel blockers (34 vs. 26%), and lipid-lowering drugs (34 vs. 29%). CONCLUSION: A need still exists for more intensified treatment of elevated blood pressure and hypercholesterolemia, especially in women. In hypertensives of both sexes, smoking and other risk factors also need to be addressed to reduce the risk of cardiovascular disease.  相似文献   
55.

Introduction

Pressure on inpatient beds often results in premature discharges, which may precipitate early readmission. This has prompted an increased interest in transitional care interventions to bridge the gap between in- and outpatient care to reduce such readmissions. Our study aimed to assess the effect of a Transitional Care Service (TCS) on readmission rates in a high pressure inpatient service which utilizes a premature discharge policy to address bed pressures.

Methods

Sixty male patients identified for crisis discharge were offered a TCS for the first ninety days after discharge. Patients received a structured intervention consisting of four phone calls and one home visit, focusing on maintaining adherence, appointment reminders and psychoeducation. The TCS patients were retrospectively compared to a matched control group in terms of readmission after 90 days. Data was collected on adherence to medication, attendance of appointments and incidence of substance use.

Results

There was no significant difference in readmission rates. Prevalence of substance use was very high (90%), especially methamphetamine use (48%). Adherence dropped from 45% (n = 27) at one week post-discharge to 25% (n = 15) at 90 days.

Conclusion

Structured telephone-based transitional interventions have no effect on readmission rates in this setting. Prematurely discharged patients require more comprehensive support with focus on comorbid substance use.  相似文献   
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BACKGROUND: Social inequalities of manifest coronary heart diseases are well documented in modern societies. Less evidence is available on subclinical atherosclerotic disease despite the opportunity to investigate processes underlying this association. Therefore, we examined the relationship between coronary artery calcification as a sign of subclinical coronary atherosclerosis, socio-economic status and established cardiovascular risk factors in a healthy population. DESIGN: Cross-sectional. METHODS: In a population-based sample of 4487 men and women coronary artery calcification was assessed by electron beam computed tomography quantified by the Agatston score. Socio-economic status was assessed by two indicators, education and income. First, we investigated associations between the social measures and calcification. Second, we assessed the influence of cardiovascular risk factors on this association. RESULTS: After adjustment for age, men with 10 and less years of formal education had a 70% increase in calcification score compared with men with high education. The respective increase for women was 80%. For income the association was weaker (among men 20% higher for the lowest compared with the highest quartile; and among women 50% higher, respectively). Consecutive adjustment for cardiovascular risk factors significantly attenuated the observed association of socio-economic status with calcification. CONCLUSIONS: Social inequalities in coronary heart diseases seem to influence signs of subclinical coronary atherosclerosis as measured by coronary artery calcification. Importantly, cumulation of major cardiovascular risk factors in lower socio-economic groups accounted for a substantial part of this association.  相似文献   
59.
The association between various human leucocyte antigen (HLA) alleles and the occurrence of acute and chronic graft-versus-host disease (GVHD) was evaluated in 493 haematopoietic stem-cell transplant (HSCT) patients with HLA identical sibling donors. There were 307 men and 186 women with a median age of 30 years (0.2-77). Most of the patients had a haematological malignancy and received total body irradiation or busulphan combined with cyclophosphamide as conditioning before transplantation. GVHD prophylaxis consisted of monotherapy with methotrexate (MTX) or cyclosporin (CsA) in 118 patients, MTX + CsA in 323, T-cell depletion in 28 and other combinations in 24. In total, 84 patients (17%) received a peripheral blood stem-cell graft, whereas the rest received bone marrow. The cumulative incidence of acute GVHD grades II-IV was 20%, and chronic GVHD 46%. In the multivariate analysis, HLA-A10 (OR 2.14, CI 1.04-4.41, P = 0.03) and HLA-B7 (OR 1.80, CI 1.04-3.12, P = 0.03) correlated with an increased risk of acute GVHD grades II-IV. We also found an association between HLA-B27 (RR 0.60, CI 0.37-0.95, P = 0.04) and a lower incidence of chronic GVHD. These HLA alleles were independent of other known risk factors for acute or chronic GVHD, as shown by multivariate analysis. These results show that major histocompatibility comlex (MHC) alleles may influence the incidence of GVHD in HSCT with HLA identical sibling donors.  相似文献   
60.
AIMS: Left ventricular (LV) and biventricular (BiV) pacing are potentially superior to right ventricular (RV) apical pacing in patients undergoing atrioventricular (AV) junction ablation and pacing for permanent atrial fibrillation. METHODS AND RESULTS: Prospective randomized, single-blind, 3-month crossover comparison between RV and LV pacing (phase 1) and between RV and BiV pacing (phase 2) performed in 56 patients (70+/-8 years, 34 males) affected by severely symptomatic permanent atrial fibrillation, uncontrolled ventricular rate, or heart failure. Primary endpoints were quality of life and exercise capacity. Compared with RV pacing, the Minnesota Living with Heart Failure Questionnaire (LHFQ) score improved by 2 and 10% with LV and BiV pacing, respectively, the effort dyspnoea item of the Specific Symptom Scale (SSS) changed by 0 and 2%, the Karolinska score by 6 and 14% (P<0.05 for BiV), the New York Heart Association (NYHA) class by 5 and 11% (P<0.05 for BiV), the 6-min walked distance by 12 (+4%) and 4 m (+1%), and the ejection fraction by 5 and 5% (P<0.05 for both). BiV pacing but not LV pacing was slightly better than RV pacing in the subgroup of patients with preserved systolic function and absence of native left bundle branch block. Compared with pre-ablation measures, the Minnesota LHFQ score improved by 37, 39, and 49% during RV, LV, and BiV pacing, respectively, the effort dyspnoea item of the SSS by 25, 25, and 39%, the Karolinska score by 39, 42, and 54%, the NYHA class by 21, 25, and 30%, the 6-min walking distance by 35 (12%), 47 (16%), and 51 m (19%) and the ejection fraction by 5, 10, and 10% (all differences P<0.05). CONCLUSIONS: Rhythm regularization achieved with AV-junction ablation improved quality of life and exercise capacity with all modes of pacing. LV and BiV pacing provided modest or no additional favourable effect compared with RV pacing.  相似文献   
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