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991.
OBJECTIVE: To compare stages IB1 and IB2 cervical cancers treated with radical hysterectomy (RH) and to define predictors of nodal status and recurrence. METHODS: Patients with stage IB cervical cancers undergoing RH between 1990 and 2000 were evaluated and clinicopathological variables were abstracted. The perioperative complication rate, estimated blood loss (EBL), and OR time were also tabulated. Variables were analyzed using X(2) and t tests. Disease-free survival (DFS) was calculated by Kaplan-Meier method. Multivariate analysis was performed via stepwise logistic regression. Cox-proportional hazards were used to identify independent predictors of recurrence. RESULTS: RH was performed on 109 stage IB1 and 86 stage IB2 patients. Mean age, EBL, and perioperative complication rates were similar. Overall, 38 patients (14 IB1 vs. 24 IB2) had positive nodes (P = 0.01) including 9 patients with positive para-aortic nodes (2 IB1 and 7 IB2). Parametrial involvement (PI) and outer 2/3 depth of invasion (DOI) were significantly more common in the IB2 tumors as well. Patients with IB2 disease received adjuvant radiation more frequently than IB1 patients (52% vs. 37%, P = 0.04). Univariate predictors of nodal status included lymphovascular space involvement (LVSI) (P = 0.001), DOI (P = 0.011), PI (P = 0.001), and stage (P = 0.011). Multivariate analysis identified only LVSI (OR 6.4, CI 2.4-17, P = 0. 0002) and PI (OR 8, CI 3.1-20, P = 0. 0001) as independent predictors of positive nodes. With a median follow-up of 35 months, estimates of DFS revealed tumor size (P = 0.008), nodal status (P = 0.0004), LVSI (P = 0.002), PI (P = 0.004), and DOI (P = 0.0004) as significant univariate predictors. Neoadjuvant chemotherapy, age, grade, histology, and adjuvant radiation were not associated with recurrence. The significant independent predictors of DFS were LVSI (ROR 5.7, CI 2-16, P = 0.0064) and outer 2/3 DOI (OR 5.8, CI 2-20, P = 0.0029). Neither tumor size nor nodal status was a significant predictor of DFS. CONCLUSIONS: The prognosis in stage IB cervical cancer seems to be most influenced by presence of LVSI and DOI and not by tumor size as the staging criteria would suggest. These factors are best determined pathologically after radical hysterectomy. This report contains the largest comparison of IB1 and IB2 patients managed by RH. Tumor size failed to predict recurrence or nodal status when stratified by LVSI, DOI, and PI. Treatment decisions based on tumor size alone should be reconsidered.  相似文献   
992.
993.
The current scientific literature relevant to the use of prolotherapy for osteoarthritis, low back pain, and other musculoskeletal conditions was reviewed and critically analyzed to determine a clinical effect. Three randomized, controlled studies were found studying the use of dextrose/glycerine/phenol prolotherapy for chronic low back pain; however, they were inconclusive due to the lack of adequate controls, heterogeneity in patient diagnoses, and variations in solutions injected. Two randomized, controlled studies were found that provide some evidence supporting the use of 10% dextrose prolotherapy for osteoarthritis. The sample size of the study (n = 13) involving osteoarthritic thumbs and fingers may have been too small to be strongly conclusive; however, it provides preliminary data to support future studies. Two studies involving osteoarthritic knees report an improvement in anterior cruciate ligament laxity; however, they did not have control groups for comparison. Only case reports were found supporting the pursuit of controlled clinical studies of prolotherapy for chronic neck pain. On the basis of the scarce body of literature critically reviewed to date, the clinical efficacy of prolotherapy in treating osteoarthritis, low back pain, and other musculoskeletal conditions remains inconclusive.  相似文献   
994.
995.
In the UK, the introduction of the New Deal on junior doctors' hours has placed constraints on permissible senior house officer (SHO) rosters. This makes it difficult to construct a rota that satisfies SHOs' annual leave and study leave requirements, yet remains compliant with the New Deal. A solution is the use of a computer. A computer program is described that generates compliant, full shift, SHO rosters in accordance with annual leave requests. This has been in routine use at the Oxford Radcliffe Hospitals Trust emergency department for the past 18 months. The program lends itself to, but is not specific to A&E applications; it can be used to generate compliant full shift rosters for other specialties. A copy of the program can be downloaded free of charge from a web site.  相似文献   
996.
BACKGROUND: Previous studies of acute lower gastrointestinal bleeding (LGIB) have focused on evaluation and therapy. Measurement of long-term outcome has been rare. The purpose of this study was to document rebleeding and survival rates in patients with acute LGIB. METHODS: A retrospective review of all patients undergoing technetium-labeled red blood cell scans for LGIB from January of 1997 to December of 2002 was performed. Rebleeding was defined as identification of enteric bleeding requiring a transfusion 2 or more weeks after the initial bleeding episode. RESULTS: A total of 119 patients met inclusion criteria. Rebleeding was documented in 14 of 102 patients surviving for more than 2 weeks. The actuarial rebleeding rate was 15% at 2 years. No factors were identified that portended a higher likelihood of rebleeding. The 30-day mortality was 18% and the median survival was 60 months for the entire cohort. Of the 36 patients in whom cause of death was documented, 4 died of surgical complications and a single patient died as a direct result of hemorrhage. CONCLUSIONS: Rebleeding after an initial episode of LGIB occurs in a small percentage of individuals. Although survival is poor for patients with LGIB, few patients die as a direct consequence of hemorrhage.  相似文献   
997.
BACKGROUND: The purpose of the current study was to evaluate whether a totally implanted valved subcutaneous port system would have fewer complications as compared to a standard nonvalved port. METHODS: Study subjects requiring port placement were randomized to receive a valved port (PASV; Boston Scientific, Natick, MA) or a nonvalved port (BardPort; Bard Accesss Systems, Salt Lake City, UT). Each port was placed with standard operative technique. Difficulty with blood return, excess time spent accessing the port, and required interventions were reported over the initial 180 days of port usage. RESULTS: Seventy-three patients were randomized to receive either a valved port (n = 37) or a nonvalved port (n = 36). No major complications were identified from port placement, and there were no differences in rates of infection between the 2 ports. A reported inability to withdraw blood was noted in the valved port group on 21 of 364 (5.8%) port accessions and in the nonvalved port group on 37 of 341 (11%) accessions (P = 0.02). Significantly more total time was spent ensuring adequate blood draw from nonvalved ports as opposed to valved ports (750 minutes vs. 1545 minutes, respectively) (P <0.03). CONCLUSIONS: This study revealed that the PASV valved port is associated with significantly fewer instances of poor blood return and less nursing access time, indicating that a port with a PASV valve may be superior to a nonvalved device.  相似文献   
998.
BACKGROUND: Current perioperative cardiac risk assessment tools use historic and surgical factors to stratify patient risk. Polymorphisms in platelet glycoprotein (GP) IIIa and GPIbalpha are associated with myocardial ischemic risk in nonsurgical settings, but their relation to perioperative ischemia is unclear. The authors hypothesized that platelet genotype would be an independent predictor of postoperative myocardial ischemia and would improve risk assessment when added to clinical factors. METHODS: One hundred ninety-six patients who underwent infrainguinal, abdominal aortic, or thoracoabdominal vascular surgery were evaluated for clinical and genetic factors that might predict the development of postoperative myocardial ischemia. Genomic DNA was genotyped for the Leu33Pro polymorphism of GPIIIa and the Thr145Met polymorphism of GPIbalpha. Myocardial ischemic outcome was determined by review of the medical record for cardiac death or myocardial infarction and by surveillance troponin I and automated continuous 12-lead electrocardiographic analysis. RESULTS: Sixty-five patients (33%) experienced one or more ischemic endpoints (2% death, 5% myocardial infarction, 20% troponin+, 22% electrocardiogram+). The Pro33 (adjusted odds ratio [OR], 2.4 [95% confidence interval, 1.2-6.2]) and Met145 (OR 3.4 [1.4-9.3]) genotypes were independent predictors of composite ischemic outcome by multivariate regression, as were diabetes mellitus (OR 4.0 [1.7-12.5]), abdominal aortic surgery (OR 4.1 [1.7-14.4]), and thoracoabdominal aortic surgery (OR 6.4 [2.7-23.8]). The addition of platelet gene polymorphisms to clinical factors improved fit (likelihood ratio testing chi-square = 13.5, P < 0.001) of an ischemia prediction model. The derived risk assessment tool had a receiver operator characteristic curve of 0.73 (0.65-0.81) compared with 0.64 (0.57-0.74) for a model excluding genetic factors (P = 0.04). A significant relation between the GPIbalpha polymorphism and ischemic outcome remained after excluding electrocardiographic ischemia from the composite endpoint. CONCLUSIONS: Platelet polymorphisms are independent risk factors for postoperative myocardial ischemia and improve a risk prediction model when added to historic and surgical risk factors.  相似文献   
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