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   2637878篇
  免费   198743篇
  国内免费   4986篇
耳鼻咽喉   37790篇
儿科学   83928篇
妇产科学   76063篇
基础医学   371028篇
口腔科学   79553篇
临床医学   229110篇
内科学   512070篇
皮肤病学   58375篇
神经病学   212641篇
特种医学   105412篇
外国民族医学   879篇
外科学   403756篇
综合类   64342篇
现状与发展   9篇
一般理论   918篇
预防医学   195803篇
眼科学   62111篇
药学   199365篇
  7篇
中国医学   5389篇
肿瘤学   143058篇
  2018年   24051篇
  2015年   24247篇
  2014年   33664篇
  2013年   51634篇
  2012年   68636篇
  2011年   72542篇
  2010年   43084篇
  2009年   41255篇
  2008年   69681篇
  2007年   74529篇
  2006年   75513篇
  2005年   73444篇
  2004年   71918篇
  2003年   69351篇
  2002年   68152篇
  2001年   122310篇
  2000年   126058篇
  1999年   107354篇
  1998年   29268篇
  1997年   26617篇
  1996年   26111篇
  1995年   25095篇
  1994年   23591篇
  1993年   22130篇
  1992年   86560篇
  1991年   83933篇
  1990年   82174篇
  1989年   80081篇
  1988年   74566篇
  1987年   73399篇
  1986年   70080篇
  1985年   67225篇
  1984年   50361篇
  1983年   43239篇
  1982年   25667篇
  1981年   23213篇
  1980年   21751篇
  1979年   48270篇
  1978年   34033篇
  1977年   29064篇
  1976年   26823篇
  1975年   29307篇
  1974年   35464篇
  1973年   34212篇
  1972年   32027篇
  1971年   30116篇
  1970年   28134篇
  1969年   26723篇
  1968年   24848篇
  1967年   22377篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
52.
Abstract

Objective: To understand the origin of extremely high gonadotropin levels in a perimenopausal woman.

Methods: A 52-year-old woman with a 2?months of amenorrhea followed spontaneous menstrual cycles recovery was referred to our outpatient clinic with elevated follicle-stimulating hormone (FSH, 483 mUI/ml), luteinizing hormone (LH, 475 mUI/ml) and prolactin (PRL, 173?ng/ml). She was known to take levosulpiride. The gonadotropin levels did not fit with the clinical features.

Results: A gonadotroph tumor was ruled out. Further analysis confirmed constantly high FSH, LH and PRL levels. The measurements were repeated using different analytical platforms with different results. After serial dilutions, nonlinearity was present suggesting an immunoassay interference. After post-polyethylene glycol recovery, hormone levels appeared in the normal range. Anti-goat antibodies were recognized in the serum of the patient.

Conclusions: This case report shows a case of falsely abnormal high gonadotropin and PRL levels in a woman during menopause transition. In the clinical practice the evaluation of gonadotropin profile is not recommended at this age, but the abnormal levels stimulated further evaluation. An interference in the assay due to anti-goat antibodies resulted in abnormally high level of FSH and LH. A strict collaboration between clinicians and the laboratory is needed, when laboratory findings do not correspond to clinical findings.  相似文献   
53.
54.
55.
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis.  相似文献   
56.
57.
58.
59.
60.
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