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   2278281篇
  免费   171952篇
  国内免费   3680篇
耳鼻咽喉   33567篇
儿科学   77773篇
妇产科学   65284篇
基础医学   328894篇
口腔科学   63451篇
临床医学   198221篇
内科学   447465篇
皮肤病学   49110篇
神经病学   177964篇
特种医学   90090篇
外国民族医学   973篇
外科学   351126篇
综合类   49145篇
现状与发展   1篇
一般理论   644篇
预防医学   171511篇
眼科学   51999篇
药学   171614篇
  3篇
中国医学   4406篇
肿瘤学   120672篇
  2018年   22373篇
  2016年   18867篇
  2015年   21491篇
  2014年   29907篇
  2013年   45701篇
  2012年   62638篇
  2011年   66814篇
  2010年   39808篇
  2009年   37719篇
  2008年   64284篇
  2007年   69346篇
  2006年   69986篇
  2005年   68406篇
  2004年   66478篇
  2003年   64330篇
  2002年   63266篇
  2001年   105837篇
  2000年   109301篇
  1999年   93032篇
  1998年   26207篇
  1997年   23532篇
  1996年   23907篇
  1995年   22668篇
  1994年   21470篇
  1993年   19883篇
  1992年   74494篇
  1991年   73190篇
  1990年   71804篇
  1989年   69055篇
  1988年   64075篇
  1987年   62989篇
  1986年   59327篇
  1985年   56835篇
  1984年   42731篇
  1983年   36428篇
  1982年   21584篇
  1981年   19369篇
  1980年   17767篇
  1979年   39366篇
  1978年   27528篇
  1977年   23660篇
  1976年   22287篇
  1975年   24288篇
  1974年   28528篇
  1973年   27483篇
  1972年   25813篇
  1971年   23760篇
  1970年   22294篇
  1969年   20886篇
  1968年   19400篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
In the 6th Basic Plan for Long-Term Electricity Supply and Demand (6th BPE) for Korea, for the first time, the environmental costs of air pollution caused by oxides of sulfur (SOx), oxides of nitrogen (NOx), and particulate matters (PM) from power plants were estimated and included. However, several deficiencies in evaluating the environmental costs were found. In this study, (1) the validity of the environmental costs used in the 6th BPE was assessed, (2) a systematic approach was suggested and used to improve the environmental costs estimation, and (3) the sensitivity of the cost of generating electricity to the environmental costs by fuel type with the proposed approach was discussed. We found that the applied environmental costs used in the 6th BPE did not fully include the demographic characteristics of Korea. By applying more realistic parameter values, it was found that the newly estimated environmental cost was about 23 times higher than the cost estimated in the original 6th BPE for coal-fired power plants and about 1.5 times higher for liquefied natural gas (LNG)-fired power plants, suggesting that LNG-fired power plants are more economical if using more realistic environmental costs. Thus, it is critical to check the validity of parameter values when calculating environmental costs.  相似文献   
95.
96.
97.
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   
98.
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   
99.
100.
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