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41.
Several authors have studied the influence of varied centric and eccentric occlusal relationships on neuromusculature. However, the authors know of no research comparing the effects on mandibular muscle activity of different occlusal functions in protrusive guidance.

This study used an orthopedic splint to compare the influence exerted by different protrusive occlusal functions on elevator muscle activity. The paper also explains the neuromusculature involved and quantifies the activity in comparison with registration in the mandibular centric position.  相似文献   
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The competence network for viral hepatitis (HepNet) was founded in 2002 with funding from the German government and has influenced the research on viral hepatitis in Germany. HepNet collaborator sites have been involved in numerous national and international investigator-initiated, as well as industry-sponsored, phase 1–3 studies. Within the HepNet Study-House, many groundbreaking investor-initiated trials have been completed and are still ongoing. For example, the acute hepatitis C trials and trials on chronic hepatitis D (delta), which led to therapy optimization. Continuation of the competence network on viral hepatitis has been achieved by the foundation of the German Liver Foundation, which has been an external cooperation partner of the German Center for Infection Research (DZIF) for two years. The well-established HepNet Study-House acts here as the clinical trial platform for all DZIF hepatitis trials.  相似文献   
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Background  

The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well.  相似文献   
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Antimitochondrial antibodies are markers for primary biliary cirrhosis and probably reflect a specific defect in immunoregulation underlying this disease. Antimitochondrial antibodies and their primary biliary cirrhosis-specific subtypes were tested before and up to 6 years after orthotopic liver transplantation. Sera from 31 consecutive patients were tested, 15 patients had primary biliary cirrhosis and 16 non-primary biliary cirrhosis. Antimitochondrial antibodies were investigated under code by immunofluorescence, and primary biliary cirrhosis-specific subtypes were determined by radioimmunoassay (anti-p62, anti-p48) and complement fixation test (anti-M2, anti-M4, anti-M8). Before orthotopic liver transplantation, antimitochondrial antibodies were detected by immunofluorescence in 13 of 15 patients with primary biliary cirrhosis. Of these patients, 12 were positive for anti-p62 and 8 for anti-p48. Ten patients were positive for anti-M2, 4 patients for anti-M4 and 7 patients for anti-M8. Two primary biliary cirrhosis patients and all non-primary biliary cirrhosis patients were negative with all tests. One month after orthotopic liver transplantation, antimitochondrial antibodies titers declined or became negative by antimitochondrial antibodies immunofluorescence, 3 patients became negative by radioimmunoassay for anti-p62 and 1 for anti-p48. With complement fixation test, 4 patients became negative for anti-M2, 2 for anti-M4 and 4 for anti-M8. Antimitochondrial antibody titer reduction observed 1 month after orthotopic liver transplantation remained unchanged in most sera during the following years. A rise was observed in two patients after 4 and 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
47.
Background and objectives: Concern about primary fistula failure may contribute to the underuse of arteriovenous fistula. The objective of this study was to investigate the baseline clinical parameters associated with primary fistula success.Design, setting, participants, & measurements: Consecutive incident patients who commenced dialysis during a 28-mo period in a regional renal program were studied. Data on patient-related variables and on surgical approach (e.g., whether the surgeons routinely assess vessel size during the operation) were collected. Primary fistula success was defined as an arteriovenous fistula that was able to afford successful dialysis for 3 h with blood pump speed of ≥300 ml/min for three consecutive sessions.Results: A total of 205 (69%) patients had an AVF attempted as their first vascular access. The overall primary success rate was 64% and was similar for radiocephalic and brachiocephalic fistula. Logistic regression was done separately for patients with the two types of fistula because of the presence of statistical interaction. For radiocephalic fistula, male gender was the only parameter associated with primary fistula success (odds ratio 3.57; P = 0.01). The presence of comorbidity was not significantly associated with primary fistula failure.Conclusions: Despite significant patient comorbidity, there was a high primary fistula success rate among this incident hemodialysis cohort. Given that vessel size may be the ultimate determinant of fistula success, if surgeons assess vessel size perioperatively, then the presence of significant comorbidity might not preclude arteriovenous fistula from being attempted as the initial access.Given the well-documented advantages of arteriovenous fistula (AVF) over arteriovenous graft and central venous catheter (CVC), the current Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines suggest that AVF should be attempted as the initial vascular access in at least 50% of incident patients and that at least 40% of prevalent hemodialysis (HD) patients should undergo dialysis with an AVF (15). Despite these recommendations, it is clear that AVF are underused in many centers in North America, especially when compared with European centers (6,7). Recent data suggest that only 32% of prevalent US HD patients undergo dialysis with an AVF (8). In Canada, AVF are used by 53% of prevalent and only 26% of incident HD patients (7).One of the fears that may reduce the use of AVF is the high primary fistula failure rate (i.e., failure of AVF to mature) (9). Identifying risk factors that contribute to primary fistula failure may help clinicians and patients make an informed decision as to for whom to attempt an AVF. Only a few studies have prospectively examined the risk factors associated with primary fistula failure, which has been reported in 20 to 50% of patients (912).Most studies that have evaluated factors that are associated with primary fistula failure have typically used a retrospective design. For instance, Miller et al. (10) reported higher primary fistula failure rate in older and female patients with diabetes, although small numbers and a highly selected patient population limit the generalizability of these results. Feldman et al. (13) published data from a larger cohort (348 patients), reporting a primary success rate of 54%. Preexisting cerebrovascular disease, older age, and commencement of dialysis before access creation were noted to be associated with higher primary fistula failure in their study. Ravani et al. (11) noted that cardiovascular disease and late referral to nephrologists were associated with lower primary AVF success in patients from northern Italy.More recently, Lok et al. (14) studied a cohort of 422 HD patients who were undergoing their first AVF placement to identify preoperative clinical characteristics that are predictive of fistula failure to mature and to use this information to develop a prediction rule to estimate the risk for fistula failure to mature. This prediction rule was validated in an external data set from five North American centers. Age, peripheral vascular disease, coronary artery disease, and white race all were associated with fistula failure to mature in their study; however, in this and the previously mentioned studies, it is not clear whether there was any consistent surgical assessment performed perioperatively to guide fistula placement; as such, the results may not be applicable to programs that use pre- or intraoperative surgical assessment to guide fistula placement.Given these uncertainties, we sought to determine the association of various baseline clinical parameters with primary fistula success in a cohort that consisted of all incident dialysis patients between July 1, 1999, and November 1, 2001, in Calgary, Alberta, Canada, the majority of whom had an indirect assessment of vessel diameter intraoperatively to guide the location of fistula placement.  相似文献   
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BACKGROUND: The diagnosis of chronic hepatitis C virus infection is based on nucleic acid testing (NAT) for HCV-RNA. We evaluated whether total HCV core antigen testing could be a substitute for NAT testing. PATIENTS AND METHODS: Samples from 192 untreated chronic HCV positive patients previously tested for HCV-RNA by four different commercially available assays (SuperQuant, Amplicor HCV Monitor v 1.0 and v 2.0, Quantiplex) were tested for total HCV core antigen using the Ortho trak-C assay (Ortho Clinical Diagnostics, Raritan, NJ, USA). Furthermore, 52 HCV-RNA positive paired serum and plasma samples were analysed. Finally, inter-assay coefficients of variation for core antigen were determined by repeated testing of 59 samples. RESULTS: 172/192 (89.6 %) samples from untreated HCV patients showed positive results with the trak-C assay. Importantly, all but two trak-C positive samples were NAT positive. Only four of the twenty trak-C negative samples tested positive by two NAT assays with viral loads below 30,000 copies/mL. Moreover, HCV core antigen levels correlated significantly with HCV-RNA levels (r > 0.72; p > 0.001), gave consistent results in paired serum and plasma samples (r = 0.991), and showed a very low inter-assay variability (r = 0.943) independent of genotype. CONCLUSION: Based on the performance characteristics, easiness of use, and potential lower cost of the core Ag assay, we propose an alternative testing algorithm for establishing the diagnosis of chronic HCV infection in which the trak-C assay could substitute for NAT as the first choice for detection of HCV viraemia in anti-HCV positive individuals. NAT would only be necessary in rare cases with low viral load.  相似文献   
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