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   1418990篇
  免费   114088篇
  国内免费   3364篇
耳鼻咽喉   18471篇
儿科学   46735篇
妇产科学   41214篇
基础医学   201761篇
口腔科学   37911篇
临床医学   126675篇
内科学   286475篇
皮肤病学   33485篇
神经病学   117559篇
特种医学   54159篇
外国民族医学   464篇
外科学   212076篇
综合类   32862篇
现状与发展   3篇
一般理论   497篇
预防医学   110541篇
眼科学   31681篇
药学   98865篇
  1篇
中国医学   3361篇
肿瘤学   81646篇
  2021年   10999篇
  2019年   11798篇
  2018年   16728篇
  2017年   12788篇
  2016年   14399篇
  2015年   16159篇
  2014年   22771篇
  2013年   33744篇
  2012年   45876篇
  2011年   48419篇
  2010年   28489篇
  2009年   27319篇
  2008年   44832篇
  2007年   47392篇
  2006年   47947篇
  2005年   46389篇
  2004年   44276篇
  2003年   42163篇
  2002年   40658篇
  2001年   73056篇
  2000年   74572篇
  1999年   61616篇
  1998年   17078篇
  1997年   15514篇
  1996年   15653篇
  1995年   14863篇
  1994年   13464篇
  1993年   12635篇
  1992年   45864篇
  1991年   43529篇
  1990年   41517篇
  1989年   39588篇
  1988年   36224篇
  1987年   35391篇
  1986年   32914篇
  1985年   31319篇
  1984年   23874篇
  1983年   20090篇
  1982年   12322篇
  1981年   10871篇
  1979年   20739篇
  1978年   14622篇
  1977年   12133篇
  1976年   11404篇
  1975年   11649篇
  1974年   14015篇
  1973年   13571篇
  1972年   12662篇
  1971年   11489篇
  1970年   10928篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a rare malignant tumour of the skin, with an estimated incidence of 0.8 to five cases per 1 million people per year. OBJECTIVE: To study epidemiological, immunohistochemical and clinical features, delay in diagnosis, type of treatment and outcome of DFSP from 1982 to 2002. METHODS: Using data from the population-based cancer registry, 66 patients with pathologically proved DFSP were included (fibrosarcomatous DFSP were excluded). Each patient lived in one of the four departments of Franche-Comté (overall population of 1 million people) at the time of diagnosis. The main data sources came from public and private pathology laboratories and medical records. The rules of the International Agency for Research on Cancer were applied. RESULTS: The estimated incidence of DFSP in Franche-Comté was about three new cases per 1 million people per year. Male patients were affected 1.2 times as often as female patients were. The trunk (45%) followed by the proximal extremities (38%) were the most frequent locations. DFSP occurred mainly in young adults between 20 and 39 years of age. Mean age at diagnosis was 43 years, and the mean delay in diagnosis was 10.08 years. Our 66 patients initially underwent a radical local excision. Among them, 27% experienced one or more local recurrences during 9.6 years of follow-up. There was one regional lymph node recurrence without visceral metastases. These recurrences were significantly related to the initial peripheral resection margins. We observed a local recurrence rate of 47% for margins less than 3 cm, vs. only 7% for margins ranging from 3 to 5 cm [P=0.004; OR=0.229 (95%, CI=0.103-0.510)]. The mean time to a first local recurrence was 2.65 years. Nevertheless, there was no death due to the DFSP course at the end of the follow-up, and the final outcome was favourable. CONCLUSION: Our study emphasizes the importance of wide local excision with margins of at least 3 cm in order to prevent local recurrence. However, the recent development of inhibitors of signal transduction by the PDGFB pathway should soon modify the surgical strategy, which is often too mutilating.  相似文献   
42.
43.
44.
45.
46.
47.
48.
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
49.
50.
背景:针对糖尿病患者Lp(a)水平和冠状动脉疾病(CAD)严重程度之间关系的研究较少并且结论有争议。另外,目前尚无关于apo(a)多态性与上述疾病关系的研究。本研究旨在探讨大样本2型糖尿病患者中冠状动脉粥样硬化的程度与Lp(a)水平及apo(a)多态性的相关性。方法:连续选取227例2型糖  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