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   3126篇
  免费   152篇
  国内免费   13篇
耳鼻咽喉   41篇
儿科学   79篇
妇产科学   38篇
基础医学   427篇
口腔科学   221篇
临床医学   241篇
内科学   723篇
皮肤病学   108篇
神经病学   190篇
特种医学   140篇
外科学   287篇
综合类   22篇
一般理论   2篇
预防医学   385篇
眼科学   42篇
药学   250篇
中国医学   19篇
肿瘤学   76篇
  2023年   17篇
  2022年   45篇
  2021年   97篇
  2020年   72篇
  2019年   91篇
  2018年   128篇
  2017年   65篇
  2016年   73篇
  2015年   94篇
  2014年   132篇
  2013年   165篇
  2012年   256篇
  2011年   272篇
  2010年   144篇
  2009年   114篇
  2008年   158篇
  2007年   199篇
  2006年   141篇
  2005年   137篇
  2004年   81篇
  2003年   67篇
  2002年   72篇
  2001年   59篇
  2000年   42篇
  1999年   51篇
  1998年   42篇
  1997年   36篇
  1996年   39篇
  1995年   28篇
  1994年   32篇
  1993年   27篇
  1992年   36篇
  1991年   25篇
  1990年   23篇
  1989年   25篇
  1988年   16篇
  1987年   15篇
  1986年   15篇
  1985年   16篇
  1984年   8篇
  1983年   10篇
  1981年   10篇
  1980年   8篇
  1979年   8篇
  1978年   10篇
  1977年   10篇
  1976年   12篇
  1975年   8篇
  1969年   9篇
  1967年   8篇
排序方式: 共有3291条查询结果,搜索用时 31 毫秒
1.
2.
3.
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   
4.
5.
6.
7.
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation.  相似文献   
8.
Purine agonists prevent trophic changes caused by sympathetic denervation   总被引:1,自引:0,他引:1  
Surgical denervation of the lateral saphenous vein of the dog causes marked extraneuronal changes, both of a morphological and functional type. In an attempt to investigate the factor(s) responsible for the trophic effects exerted by the sympathetic innervation on the dog saphenous vein we studied the effects of noradrenaline, adenosine, inosine and N-ethylcarboxamidoadenosine (NECA) on vascular tissue after sympathetic denervation. The saphenous vein was denervated using either surgical or chemical (6-hydroxydopamine, 6-OHDA) methods. Noradrenaline (0.1 microgram/kg per h), adenosine (10 micrograms/kg per h), inosine (10 micrograms/kg per h) or NECA (0.1 microgram/kg per h) were delivered continuously for 5 days through Alzet minipumps connected to the vein. 6-OHDA-induced denervation resulted in morphological changes similar to those described for surgical denervation. Smooth muscle cells and fibroblasts showed ultrastructural signs of increased synthetic activity and their size was significantly increased. In confirmation of earlier studies, constant i.v. infusions of noradrenaline did not prevent the morphological changes induced by denervation. Adenosine prevented the morphological changes induced by chemical or surgical denervation. Similarly to adenosine, infused NECA prevented the structural consequences of denervation. In contrast, inosine did not prevent the changes caused by surgical denervation. The results are compatible with an involvement of purines in the trophic effects of sympathetic innervation. Moreover, the effects of adenosine do not appear to be mediated by inosine.  相似文献   
9.
10.
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