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91.
Several studies showed that l-leucine supplementation reduces adiposity when provided before the onset of obesity. We studied rats that were exposed to a high-fat diet (HFD) for 10 weeks before they started to receive l-leucine supplementation. Fat mass was increased in l-leucine-supplemented rats consuming the HFD. Accordingly, l-leucine produced a hypothalamic pattern of gene expression that favors fat accumulation. In conclusion, l-leucine supplementation worsened the adiposity of rats previously exposed to HFD possibly by central mechanisms.  相似文献   
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Many different osteotomy procedures has been proposed in the literature for dental implant site preparation. The osseodensification is a drilling technique that has been proposed to improve the local bone quality and implant stability in poor density alveolar ridges. This technique determines an expansion of the implant site by increasing the density of the adjacent bone. The aim of the present investigation was to evaluate the effectiveness of the osseodensification technique for implant site preparation through a literature review and meta-analysis. The database electronic research was performed on PubMed (Medline) database for the screening of the scientific papers. A total of 16 articles have been identified suitable for the review and qualitative analysis—11 clinical studies (eight on animals, three on human subjects), four literature reviews, and one case report. The meta-analysis was performed to compare the bone-to-implant contact % (BIC), bone area fraction occupied % (BAFO), and insertion torque of clockwise and counter-clockwise osseodensification procedure in animal studies. The included articles reported a significant increase in the insertion torque of the implants positioned through the osseodensification protocol compared to the conventional drilling technique. Advantages of this new technique are important above all when the patient has a strong missing and/or low quantity of bone tissue. The data collected until the drafting of this paper detect an improvement when the osseodensification has been adopted if compared to the conventional technique. A significant difference in BIC and insertion torque between the clockwise and counter-clockwise osseodensification procedure was reported, with no difference in BAFO measurements between the two approaches. The effectiveness of the present study demonstrated that the osseodensification drilling protocol is a useful technique to obtain increased implant insertion torque and bone to implant contact (BIC) in vivo. Further randomized clinical studies are required to confirm these pieces of evidence in human studies.  相似文献   
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OBJECTIVES: The purpose of this study was to evaluate the value of platelet reactivity (PR) in predicting the response to treatment and outcome in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention assisted by glycoprotein (GP) IIb/IIIa inhibition. BACKGROUND: There is limited prognostic information on the role of spontaneous or drug-modulated PR in STEMI patients. METHODS: The PR was measured with Platelet Function Analyzer (PFA)-100 and light transmission aggregometry (LTA) using adenosine diphosphate as agonist in 70 consecutive STEMI patients at entry (PR-T0), 10 min after GP IIb/IIIa bolus (PR-T1), and discharge (PR-T2) and in 30 stable angina (SA) patients (PR-SA). Complete platelet inhibition (CPI) was based on closure time >300 s by PFA-100 and percentage inhibition of platelet aggregation >95% by LTA. Clinical, electrocardiographic, and angiographic responses to treatment during 1-year follow-up were collected. RESULTS: According to both techniques, PR-T0 was higher than: 1) PR-T2 and PR-SA; 2) in those without CPI at T1; and 3) in patients with final Thrombolysis In Myocardial Infarction (TIMI) flow grade <3. The PR-T0 assessed with PFA-100 correlated with: 1) corrected TIMI frame count (r = -0.6, p < 0.001); 2) ST-segment resolution (r = 45, p < 0.001); and 3) creatine kinase-MB (r = -0.47, p < 0.001). At 1 year, patients with high PR-T0 showed an adjusted 5- to 11-fold increase in the risk of death, reinfarction, and target vessel revascularization (hazard ratio [HR] 11, 95% confidence interval [CI] 1.5 to 78 [p = 0.02] in PFA-100; HR 5.2, 95% CI 1.1 to 23 [p = 0.03] in LTA). CONCLUSIONS: The PR at entry affects response to GP IIb/IIIa inhibition, mechanical treatment, and long-term outcome in STEMI patients undergoing primary intervention.  相似文献   
95.
OBJECTIVES: We sought to evaluate the mid-term outcome of hospital survivors with extracardiac Fontan circulation. BACKGROUND: Few data exist about the mid-term and long-term results of the extracardiac Fontan operation. METHODS: From November 1988 to November 2003, 221 patients underwent an extracardiac Fontan procedure as primary (9 patients) or secondary (212 patients) palliation, at a mean age of 72.2 months (range 13.1 to 131.3 months). A total of 165 of 193 early survivors underwent programmed noninvasive follow-up evaluations and at least one cardiac catheterization. RESULTS: The overall survival, including operative deaths, was 85% at 15 years. Freedom from late failure among hospital survivors is 92% at 15 years. A total of 127 of 165 survivors (77%) were in New York Heart Association functional class I. The incidence of late major problems was 24% (42 major problems in 36 of 165 patients): 19 patients had arrhythmias (11%), 5 patients had obstruction of the extracardiac conduit (3%) and 6 of the left pulmonary artery (3.5%), and 5 patients experienced ventricular failure (3%), leading to heart transplantation in 3 patients. Protein-losing enteropathy was found in two patients (1%). The incidence of late re-interventions was 12.7% (21 of 165 patients, including 15 epicardial pacemaker implantations). Four patients died (2.3%), two after heart transplantation. CONCLUSIONS: After 15 years of follow-up, the overall survival, the functional status, and the cardiopulmonary performance of survivors of the extracardiac Fontan procedure compare favorably with other series of patients who underwent the lateral tunnel approach. The incidence of late deaths, obstructions of the cavopulmonary pathway, re-interventions, and arrhythmias is lower than that reported late after other Fontan-type operations.  相似文献   
96.
Six patients showing at coronary angiography normal coronary arteries during dyastole, but a segmental constriction of the left anterior descending artery during systole, were studied. Four of these patients in which the degree of systolic artery narrowing was more evident had typical angina and positive stress test. In two of these cases, a probable idiopathic cardiac hypertrophy was present. The pathogenetic significance of the angiographic findings are discussed, on the basis of common knowledge of coronary physiology and of pathophysiology of angina with normal coronary arteries.  相似文献   
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We conducted a retrospective analysis of all allogeneic stem cell transplantation (ASCT) patients started on extracorporeal photopheresis (ECP) for the management of steroid-dependent (SD) or steroid-refractory (SR) cutaneous chronic graft-versus-host disease (cGVHD) following ASCT during a 36-month period (9/98-8/01). Only SD or SR patients who were treated by ECP after day 100 and who received at least 4 weeks of ECP were considered evaluable for this analysis. Out of 64 ASCT patients reviewed, 32 patients met the inclusion criteria. All 32 patients had been previously treated with systemic corticosteroids with 11 (34%) being SR and 21 (66%) SD. Cutaneous cGVHD was extensive in 28 patients (88%) and was accompanied by visceral (hepatic, gastrointestinal) cGVHD in 23 patients (72%). The 32 evaluated patients had received a median of three prior therapies before ECP, most commonly systemic corticosteroids, tacrolimus, and mycophenolate mofetil. Patients received a median of 36 ECP sessions (range 12-98) over a median of 5.3 months (range 1-28), with a median of six sessions per month. The complete response (CR) rate was 22% (n=7) and the partial response rate was 34% (n=11). In all, 28 patients were on systemic corticosteroid therapy at ECP initiation and 18 patients achieved 50% dose reduction while on ECP, yielding a 64% steroid-sparing response rate. Of seven CRs, five are ongoing. A total of 11 (34%) patients have died after ECP, with all cases due to visceral cGVHD or cGVHD-related infectious complications. All 21 surviving patients remain on at least some immunosuppressive cGVHD therapy (including ECP in eight). Overall, ECP displays a substantial response rate and, in particular, steroid-sparing activity in SR/SD extensive cutaneous cGVHD. However, most patients continue to require at least some chronic therapy and cGVHD-related morbidity and mortality remain high.  相似文献   
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