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81.
1. The absolute bioavailability and absorption kinetics of nicotine were investigated in 13 healthy adult male smokers following single and multiple applications of a nicotine transdermal system (NTS), designed to release nicotine at an approximate rate of 1.5 mg h-1 over 24 h. The absorption of nicotine from the single NTS application was calculated with reference to a simultaneous intravenous infusion (i.v.) of deuterium-labelled nicotine. 2. The mean input time (MIT) and mean absorption time (MAT) for nicotine following application of NTS for 24 h were 7.7 and 4.2 h, respectively. 3. Following NTS removal, the mean apparent nicotine elimination half-life was 2.8 h, compared with 2.0 h following i.v. nicotine, reflecting continued absorption of nicotine following NTS removal. 4. The mean amount of nicotine absorbed from the NTS after the 24 h application was 20.9 mg, which represents about 68% of the amount released from the system; the remaining 32% was lost from the system during daily activities. 5. The ratio of AUC values for the metabolite cotinine relative to nicotine was similar whether nicotine was administered transdermally or intravenously. 6. Following i.v. administration, the mean nicotine clearance was 72 l h-1 (coefficient of variation 29%). Since coefficients of variation in AUC values following NTS and i.v. treatments were similar, transdermal administration of nicotine was not associated with increased interindividual variability in plasma nicotine concentrations. 7. No significant changes were seen in the pharmacokinetics of nicotine between single and multiple applications of NTS. 8. As expected from the higher total plasma nicotine concentrations, the incidence of adverse effects was higher following simultaneous intravenous and transdermal administration of nicotine. The most frequently reported systemic side effects were nervousness and headache: mild itching was the most frequent topical effect.  相似文献   
82.
参三七皂甙Rg1对实验性血栓形成的影响及其机制探讨   总被引:14,自引:0,他引:14  
用大鼠动静脉血栓形成模型,研究参三七皂甙Rg1抗血栓作用。结果表明,参三七皂甙Rg1可明显降低实验性血栓形成,对大鼠血浆纤溶系统亦有明显作用,可升高血浆中组织纤溶酶原激活物(t-PA)活性和活性型t-PA百分比,降低组织纤溶酶原激活物抑制剂(PAI)活性。同时利用培养大鼠血管内皮细胞实验,发现Rg1可以剂量依赖性提高血管内皮细胞一氧化氮(NO)释放。提示Rg1抗血栓作用与增强纤溶系统活性,促进血管内皮NO释放有关。  相似文献   
83.
用肾性高血压左室肥厚(LVH)大鼠模型,观察了间硝地平(m-Nif)和硝苯地平(Nif)长期给药(ig20mg·kg-1·d-1持续9周)对左室舒张功能、左心室肌和大脑线粒体及血管钙含量的影响。与假手术组相比,LVH组左室顺应性明显下降,僵硬度增高,左心室肌和大脑线粒体及尾动脉和主动脉钙含量增加。与LVH组相比,m-Nif和Nif各组左室顺应性改善,僵硬度降低(P<0.01),左心室肌线粒体及尾动脉和主动脉钙含量较LVH组显著降低(P<0.01)。两药在作用强度上无显著差异。  相似文献   
84.
Innovation in clinical method: diabetes care and negotiating skills   总被引:6,自引:1,他引:5  
The development of a method to facilitate clinical negotiationwith diabetic patients is described. The principles of the methodincorporate patient centredness, an assessment of readinessto change and some elements of motivational interviewing. Asimple low cost technology is part of the innovative method.Details of the method and its application are published beforethe results of a randomized controlled trial to ensure thatthe techniques are in the public domain before the outcome ofthe trial is known.  相似文献   
85.
Leucocytoclastic vasculitis associated with hepatitis C virus antibodies   总被引:1,自引:1,他引:0  
The actiopathogenesis of leucocytoclastic vasculitis is still unknown, but recently hepatitis C virus (HCV) has been suggested as trigger of autoimmunity. We report a case of a 26-yr-old patient with purpura due to leucocytoclastic vasculitis associated with hepatitis C virus infection. Laboratory findings showed AST, ALT, gamma GT within normal limits, positive antibodies to HCV (IIF and Riba II) and polymerase chain reaction for HCV RNA. Anti-nuclear antibodies, IgG and IgM anti- cardiolipin antibodies, anti-platelet antibodies and anti-neutrophil cytoplasmic antibodies with perinuclear pattern were also present. A skin biopsy specimen of a purpuric lesion showed leucocytoclastic vasculitis with small vessel thrombosis and perivascular deposition of IgM and fibrinogen on immunofluorescence study. This case shows a role of HCV in leucocytoclastic vasculitis; it is possible that this HCV can induce autoimmunity independently of cryoglobulins and liver involvement.   相似文献   
86.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
87.
Kaposi's sarcoma is a vascular tumour of multifocal origin occurring primarily on the extremities. The case of a 45-year-old HIV negative and HHV-8 positive man with an asymptomatic reddish macular lesion on the inner layer of the prepuce is described. Although primary penile Kaposi's sarcoma is a relatively uncommon disorder in HIV negative men, dermatologists and venereologists should consider this possibility when treating non-specific penile lesions. A minimal penile lesion with non-distinctive clinical features may sometimes be the exclusive manifestation of Kaposi's sarcoma, making histologic evaluation necessary to establish the diagnosis.  相似文献   
88.
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.  相似文献   
89.
90.

Objective

To assess hypothetical acceptance of the human papillomavirus (HPV) vaccine for themselves and a daughter age 9–12 years among Appalachia Ohio women.

Methods

Women with an abnormal Pap smear and randomly selected women with a normal Pap smear from 17 clinics completed an interview in 2006–2008.

Results

From 1131 original study participants, 807 (71%) completed a survey about the HPV vaccine for their daughters and themselves. Nearly half, 380 (47%), of the participants had heard of a vaccine to prevent cancer, and 362 (95%) of respondents had heard of HPV. The participants were then told that the FDA had approved a vaccine to prevent HPV. Only 379 (38%) participants identified girls ages 9–12 years as a group who should get the vaccine. After being given the official HPV vaccine recommendation statement, 252 (31%) wanted the vaccine; 198 (25%) were “not sure”; and 353 (44%) did not want the vaccine for themselves. With respect to giving the HPV vaccine to a daughter ages 9–12 years, participants responded “yes” 445 (55%); “not sure” 163 (20%); or “no” 185 (23%). Numerous reasons were provided supporting and opposing vaccine acceptance for themselves and for a daughter. Their physician's recommendation for the HPV vaccine increased vaccine acceptance to 86% for themselves and 90% for a daughter.

Conclusion

Knowledge, acceptance, and barriers about the HPV vaccine vary among women living in Appalachia Ohio. Physician recommendation is a key facilitator for vaccine diffusion in this region.  相似文献   
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