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The reconfiguration of the supply side of the National Health Service (NHS) has stimulated an extensive debate about the need to merge NHS Trusts to maintain viable organizations. The result has been a number of mergers across the UK. Considers the underlying advantages of mergers and their drawbacks and argues that consideration must be made to addressing the long-term strategic direction of an organization rather than regarding mergers as ends in themselves. Undertakes an appraisal of alliances and joint partnerships as alternatives to merger. Considers the conditions necessary to create effective alliances and joint partnerships and the factors which will sustain them. Appraises these requirements in the context of the NHS Trusts, in which little detailed work has been undertaken on classifying, understanding and developing what effective alliances mean for these organizations.  相似文献   
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Repeated treatment with the psychostimulant amphetamine produces behavioral sensitization that may represent the neural adaptations underlying some features of psychosis and addiction in humans. In the present study we investigated the role of adenosine A(2A) receptors in psychostimulant-induced locomotor sensitization using an A(2A) receptor knockout (A(2A) KO) model. Daily treatment with amphetamine for 1 week resulted in an enhanced motor response on day 8 (by two-fold compared to that on day 1), and remained enhanced at day 24 upon rechallenge with amphetamine. By contrast, locomotor sensitization to daily amphetamine did not develop in A(2A) KO mice on day 8 or 24, and this absence was not the result of a nonspecific threshold effect. The absence of behavioral sensitization was selective for amphetamine since daily treatment with the D(1) agonist SKF81297 (2.5 mg/kg) or the D(2) agonist quinpirole (1.0 mg/kg) produced similar behavioral sensitization in both WT and A(2A) KO mice. Furthermore, coinjection of SKF81297 and quinpirole also resulted in indistinguishable locomotor sensitization in A(2A) KO and WT mice, suggesting normal D(1) and D(2) receptor responsiveness. Finally, at the cellular level A(2A) receptor inactivation abolished the increase in striatal dynorphin mRNA induced by repeated amphetamine administration. The selective absence of amphetamine-induced behavioral sensitization in A(2A) KO mice suggests a critical role of the A(2A) receptor in the development of psychostimulant-induced behavioral sensitization, and supports the pharmacological potential of A(2A) adenosinergic agents to modulate adaptive responses to repeated psychostimulant exposure.  相似文献   
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Objective  Ovarian dysgerminoma is an uncommon ovarian malignancy, Its clinicai features are special and there are many factors affecting its prognosis. If treated properly, the patient can be cured. Otherwise it may endanger the patient’s life. The aim of this study is to investigate the clinical features and factors related to prognosis of ovarian dysgerminoma. Methods  Data from 57 patients with pure ovarian dysgerminoma were analyzed retrospectively. The patients were admitted to the Cancer Center, Sun Yat-sen University from January 1.1964 to December 31, 2000. Results  The main clinical features were abdominal mass (56.1% ), abdominal pain (21.1% ), abdominal swelling (17.5%.), vaginal bleeding (5.3% )and genital tract abnormalities (5.3%). Twenty-six patients had stage I diseases, 8 stage II.9 stage III.1 stage IV and 13 recurrent and persistent diseases. The uterus was involved in 41.2% of patients with stage II -III diseases. Combined modality was given to 52 cases and a single-method treatment to 5 cases. The total overall 5 and 10-year survival rates for stages I-IV was 80.1 % and 70.0% respectively. The 5-year survival rate for stage I was 100%, stage II 55.2%. stage III 55.6% and stage IV 0%; for recurrent and persistent diseases, 72.7%. The stage I group of 12 patients. received adnexectomy and 14 patients underwent hysterectomy and adnexa removal. There was no significant difference between the 5 and 10-year survival rates (all 100%). Of the 23 patients in the stage I group to whom oniy chemotherapy was given after operation, 19 cases received 3 or more courses and were well without recurrence; 4 patients received only one course and one of them recurred 21 months after the operation. In the group of stages II and III cases, the 5-year survival rate was 86.7% for those whose chemotherapy courses were 3≥ 4 and 25.0% for patients who received less than 4 courses of chemotherapy (P<0.05). Conclusions  The prognosis of ovarian dysgerminoma is closely related to the disease stage and treatment modality. A fertility-preserving operation can be considered in early -staged patients, but caution needs to be exercised in the middle to late staged cases. Good results can be achieved with an operation-based combined modality in recurrent patients.  相似文献   
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Over a 7-year period from 1989 to 1996, 140 patients had an omental J-flap placed following type III radical abdominal hysterectomy. There were no complications as a result of omentopexy, and postoperatively no patient developed urinary fistula, pelvic infection or abscess, or intestinal obstruction even in the 35 patients who received whole pelvic radiation therapy postoperatively. The omental J-flap is a rapid, effective means of minimizing surgical morbidity following radical abdominal hysterectomy and merits consideration for routine placement at the conclusion of radical abdominal hysterectomy.  相似文献   
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PURPOSE: Current studies have provided evidence that exposure of renal epithelial cells to oxalate and calcium oxalate crystals induces lipid peroxidation and injures the cells. Since oxidant/antioxidant balance is likely to play a critical role, we determined the effect of antioxidant scavengers on production of free radicals and injury to LLC-PK1 and MDCK cells from exposure to oxalate (Ox) or Ox + calcium oxalate monohydrate (COM) crystals. MATERIALS AND METHODS: LLC-PK1 and MDCK cells were grown in monolayers and exposed to 1.0 mmol. Ox or 1.0 mmol. Ox + 500 microg. /ml. COM crystals for 120 or 240 minutes. We measured the release of lactate dehydrogenase (LDH) as a marker for cell injury and malondialdehyde (MDA) as a marker of lipid peroxidation. Superoxide and hydroxyl radicals were measured in the presence or absence of 400 U/ml. catalase, or superoxide dismutase (SOD). RESULTS: Exposure of LLC-PK1 cells to Ox resulted in a significant increase in MDA and release of LDH, which was further elevated when COM crystals were added. MDCK cells responded similarly to both challenges, but showed significantly less impact when compared with LLC-PK1 cells. Both treatments were associated with significant increase in the generation of hydroxyl and superoxide radicals by both cell types. In both cell lines, the addition of catalase or SOD significantly reduced the increase of MDA and release of LDH. CONCLUSIONS: Results of the present study indicate that both Ox and COM crystals are injurious to renal epithelial cells and the injury is associated with generation of free radicals. Cells of proximal tubular origin are more susceptible than those of distal tubules and collecting ducts. Free radical scavengers, catalase and SOD provide significant protection.  相似文献   
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While virtual learning environments (VLE) can be used in medical education as stand-alone educational interventions, they can also be used in preparation for traditional “face-to-face” training sessions as part of a “flipped classroom” model. We sought to evaluate the introduction of this model in a single module on maxillofacial radiology from a course on trauma skills. Course delegates were randomised into two groups: one was given access to an e-learning resource (test group) and the other attended a traditional didactic lecture (control group). Knowledge and confidence were assessed before and after the course with a 20-question single-best-answer paper and a 10-situation 100 mm visual analogue scale (VAS) paper, respectively. All participants were then given free access to the VLE for 30 days and were invited to take part in an e-survey. Neither group showed improvements in the single-best-answer scores, but both groups showed comparable improvements in VAS (control: median (range) values improved from 40.8 (17.7–82.5) mm to 62.8 (35.3–88.7) mm, p = 0.001; test group: from 47.7 (10.9–58.1) mm to 60.5 (32.4–75.6) mm, p = 0.005). Half of the respondents stated that they preferred the “flipped classroom” approach, and 22/22 stated that they would be “likely” or “very likely” to use an e-learning resource with expanded content. The “flipped classroom” approach was well received and there were comparable improvements in confidence. As maxillofacial radiology lends itself to online instruction with its reliance on the recognition of patterns, and problem-based approach to learning, a piloted e-learning resource could be developed in this area.  相似文献   
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