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   4103053篇
  免费   279381篇
  国内免费   9922篇
耳鼻咽喉   57775篇
儿科学   130494篇
妇产科学   111125篇
基础医学   569138篇
口腔科学   117161篇
临床医学   376038篇
内科学   791346篇
皮肤病学   91443篇
神经病学   339210篇
特种医学   158695篇
外国民族医学   1438篇
外科学   610639篇
综合类   91187篇
现状与发展   6篇
一般理论   1720篇
预防医学   325675篇
眼科学   94938篇
药学   301844篇
  102篇
中国医学   8003篇
肿瘤学   214379篇
  2018年   43810篇
  2017年   33726篇
  2016年   38337篇
  2015年   43095篇
  2014年   60664篇
  2013年   92056篇
  2012年   122325篇
  2011年   129805篇
  2010年   77836篇
  2009年   74422篇
  2008年   121820篇
  2007年   129405篇
  2006年   131155篇
  2005年   126797篇
  2004年   122197篇
  2003年   117808篇
  2002年   114652篇
  2001年   187044篇
  2000年   192535篇
  1999年   163291篇
  1998年   48480篇
  1997年   43265篇
  1996年   42903篇
  1995年   41613篇
  1994年   38635篇
  1993年   36149篇
  1992年   129754篇
  1991年   125526篇
  1990年   121332篇
  1989年   117243篇
  1988年   108362篇
  1987年   106745篇
  1986年   100817篇
  1985年   96580篇
  1984年   72638篇
  1983年   62030篇
  1982年   37355篇
  1981年   33615篇
  1979年   66747篇
  1978年   47233篇
  1977年   40022篇
  1976年   37492篇
  1975年   39594篇
  1974年   47988篇
  1973年   45810篇
  1972年   43106篇
  1971年   39923篇
  1970年   37306篇
  1969年   35274篇
  1968年   32451篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
    
Ohne Zusammenfassung  相似文献   
34.
35.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
36.
37.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease.  相似文献   
38.
39.
40.
Medullary thyroid carcinoma (MTC) is a rare form of thyroid cancer representing about 10% of all thyroid malignancies. It occurs mostly as a sporadic tumor or in association with autosomal dominant inherited cancer syndromes--multiple endocrine neoplasia (MEN) types 2A and 2B and familial MTC. Germline mutations in exons 8, 10, 11, 13, 14, 15 and 16 of the RET proto-oncogene are found in most of the familial cases. There are only a few published data reporting multiple germline mutations in the RET proto-oncogene. We have detected double germline mutations in 2 different exons on the same RET allele in two MEN 2 families. In the MEN 2A family, double germline mutation in exons 10 (Cys620Phe) and 13 (Tyr791Phe) was detected. In the MEN 2B family, beside the classical germline mutation in exon 16 (Met918Thr) a second germline mutation in exon 13 (Tyr791Phe) was found. This study revealed that MEN 2 syndromes can also be caused by double germline mutations in the RET proto-oncogene and these families can be added to small worldwide cohort of families with multiple germline mutations.  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