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   1960533篇
  免费   136985篇
  国内免费   4117篇
耳鼻咽喉   26841篇
儿科学   61470篇
妇产科学   53479篇
基础医学   279264篇
口腔科学   58462篇
临床医学   173602篇
内科学   377649篇
皮肤病学   43131篇
神经病学   151721篇
特种医学   78642篇
外国民族医学   450篇
外科学   304587篇
综合类   40162篇
现状与发展   1篇
一般理论   603篇
预防医学   145176篇
眼科学   45154篇
药学   146246篇
  8篇
中国医学   3980篇
肿瘤学   111007篇
  2018年   21447篇
  2017年   17876篇
  2016年   18967篇
  2015年   22385篇
  2014年   28399篇
  2013年   40360篇
  2012年   58124篇
  2011年   56480篇
  2010年   33340篇
  2009年   33193篇
  2008年   52075篇
  2007年   55494篇
  2006年   56695篇
  2005年   61882篇
  2004年   61716篇
  2003年   55797篇
  2002年   50127篇
  2001年   96110篇
  2000年   97513篇
  1999年   83995篇
  1998年   21088篇
  1997年   18519篇
  1996年   18703篇
  1995年   17791篇
  1994年   16522篇
  1993年   15168篇
  1992年   67206篇
  1991年   65362篇
  1990年   64023篇
  1989年   62129篇
  1988年   56727篇
  1987年   55941篇
  1986年   52311篇
  1985年   50070篇
  1984年   36508篇
  1983年   30803篇
  1982年   16843篇
  1981年   14889篇
  1979年   33577篇
  1978年   23233篇
  1977年   19612篇
  1976年   17791篇
  1975年   19761篇
  1974年   23993篇
  1973年   22699篇
  1972年   21424篇
  1971年   20198篇
  1970年   19027篇
  1969年   17821篇
  1968年   16388篇
排序方式: 共有10000条查询结果,搜索用时 627 毫秒
81.
82.
Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO.  相似文献   
83.
84.
85.
86.
A 17‐year‐old boy presented with recurring severe dermatitis of the face of 5‐months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris.  相似文献   
87.
88.
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   
89.
90.
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