首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   24909篇
  免费   1546篇
  国内免费   97篇
耳鼻咽喉   255篇
儿科学   852篇
妇产科学   621篇
基础医学   3730篇
口腔科学   409篇
临床医学   2758篇
内科学   5539篇
皮肤病学   691篇
神经病学   2374篇
特种医学   588篇
外科学   2267篇
综合类   140篇
一般理论   8篇
预防医学   2231篇
眼科学   479篇
药学   1608篇
中国医学   74篇
肿瘤学   1928篇
  2023年   185篇
  2022年   369篇
  2021年   604篇
  2020年   377篇
  2019年   596篇
  2018年   738篇
  2017年   471篇
  2016年   561篇
  2015年   658篇
  2014年   887篇
  2013年   1172篇
  2012年   1837篇
  2011年   1841篇
  2010年   980篇
  2009年   942篇
  2008年   1540篇
  2007年   1544篇
  2006年   1493篇
  2005年   1494篇
  2004年   1305篇
  2003年   1264篇
  2002年   1166篇
  2001年   335篇
  2000年   303篇
  1999年   315篇
  1998年   243篇
  1997年   214篇
  1996年   210篇
  1995年   157篇
  1994年   126篇
  1993年   141篇
  1992年   158篇
  1991年   154篇
  1990年   135篇
  1989年   170篇
  1988年   129篇
  1987年   110篇
  1986年   121篇
  1985年   123篇
  1984年   87篇
  1983年   77篇
  1982年   54篇
  1981年   61篇
  1980年   62篇
  1979年   58篇
  1978年   47篇
  1975年   53篇
  1936年   47篇
  1933年   51篇
  1932年   49篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Troppmair  Teresa  Egger  J.  Krösbacher  A.  Zanvettor  A.  Schinnerl  A.  Neumayr  A.  Baubin  M. 《Der Anaesthesist》2022,71(4):272-280
Die Anaesthesiologie - Die Qualität eines Rettungssystems zeichnet sich auch durch den effizienten Einsatz seiner personellen und Fahrzeugressourcen aus. So können im berechtigten Fall...  相似文献   
2.
3.
4.
5.
6.
7.
8.
Antioxidant preservatives prolong the quality of food and ensure the nutritional adequacy, palatability and safety of many processed foods and beverages. Effects of sodium sulfite (E221) and sorbic acid (E200) were investigated in human peripheral blood mononuclear cells (PBMC) which were purified from blood of healthy donors. Cells were stimulated with the mitogen phytohaemagglutinin in vitro, which induces proliferation of T-cells and the production of Th1-type cytokines like interferon-γ. The latter triggers enzyme indoleamine (2,3)-dioxygenase, which degrades tryptophan, and GTP cyclohydrolase I, which leads to increased neopterin production, in monocyte-derived macrophages. Sodium sulfite and sorbic acid suppressed both these biochemical changes in a dose-dependent way (P < 0.01 at 1 mM sodium sulfite and 50 mM sorbic acid). Data demonstrate a suppressive influence of sodium sulfite and sorbic acid on the activated Th1-type immune response.  相似文献   
9.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
10.
STUDY OBJECTIVES: Use of fast track has been shown to improve the emergency department flow of less urgent patients. It has been speculated, however, that this could negatively affect the care of urgent patients. The objective of this study was to determine whether a dedicated fast track for less urgent patients [Canadian Triage and Acuity scale category 4/5 (CTAS 4/5)] affected (1) the time to assessment for urgent patients (CTAS 3), (2) the length of stay for less urgent patients (CTAS 4 and 5), and (3) the left-without-being-seen rate. METHODS: In June 2003, fast track was opened in our emergency department from 13:00 to 19:00 h. A before-after intervention comparison analysis was completed for 1 week in Aug 2002 and the same week in Aug 2003. Data collected included (1) time to assessment of CTAS 3 patients, (2) the length of stay for CTAS 4/5 patients, and (3) percentage of patients who left without being seen. RESULTS: A total of 368 patients were reviewed for 2002 and 380 patients were reviewed for 2003. Median time to assessment of CTAS 3 patients presenting from 13:00 to 19:00 h was reduced from 66 min (Interquartile range: 40, 94 min) in 2002 to 60 min (IQR: 38, 108 min) after fast track was open in 2003 (P = 0.95). Median length of stay of CTAS 4 and 5 patients was reduced from 170 min (IQR: 111, 256 min) to 110 min (IQR: 69, 185 min) (P < 0.001). The overall left-without-being-seen rate decreased from 5% (20/368) to 2% (9/380). CONCLUSION: A dedicated fast track for CTAS 4/5 patients can reduce the length of stay and the left-without-being-seen rate with no impact on CTAS 3 patients seen in the main emergency department.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号