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   1496400篇
  免费   100968篇
  国内免费   4271篇
耳鼻咽喉   17849篇
儿科学   49787篇
妇产科学   39189篇
基础医学   212815篇
口腔科学   37389篇
临床医学   140900篇
内科学   286275篇
皮肤病学   26975篇
神经病学   126634篇
特种医学   56587篇
外国民族医学   366篇
外科学   210923篇
综合类   31017篇
现状与发展   1篇
一般理论   460篇
预防医学   130575篇
眼科学   31579篇
药学   107561篇
  6篇
中国医学   3784篇
肿瘤学   90967篇
  2021年   10904篇
  2019年   11642篇
  2018年   36484篇
  2017年   28205篇
  2016年   31282篇
  2015年   16016篇
  2014年   21481篇
  2013年   32683篇
  2012年   50636篇
  2011年   66281篇
  2010年   44359篇
  2009年   35608篇
  2008年   60704篇
  2007年   65160篇
  2006年   45573篇
  2005年   45475篇
  2004年   44667篇
  2003年   43479篇
  2002年   40576篇
  2001年   61069篇
  2000年   62876篇
  1999年   52406篇
  1998年   14750篇
  1997年   13460篇
  1996年   13173篇
  1995年   12546篇
  1994年   11708篇
  1993年   10970篇
  1992年   41591篇
  1991年   40836篇
  1990年   39553篇
  1989年   37403篇
  1988年   34630篇
  1987年   33727篇
  1986年   32169篇
  1985年   30658篇
  1984年   23049篇
  1983年   19605篇
  1982年   11773篇
  1979年   20806篇
  1978年   14822篇
  1977年   12067篇
  1976年   11883篇
  1975年   12115篇
  1974年   14817篇
  1973年   14473篇
  1972年   13356篇
  1971年   12418篇
  1970年   11504篇
  1969年   10429篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries.  相似文献   
62.
Leocani  L.  Comi  G. 《Neurological sciences》2006,27(1):s27-s29
Neurological Sciences - Brain plasticity, intended as the pattern of functional and structural changes in responses to environmental physiological or pathological events, is underlined by several...  相似文献   
63.
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   
64.
65.
66.
67.
68.
69.
Primary chemotherapy administered to breast cancer patientsis the best model to identify baseline features able to predictwhich patients may be most likely to benefit or not from a cytotoxicregimen. In the March issue of Annals of Oncology two papersevaluated the predictive role of immunohistochemical p53 expressionon  相似文献   
70.
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