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   6981篇
  免费   368篇
  国内免费   40篇
耳鼻咽喉   66篇
儿科学   131篇
妇产科学   37篇
基础医学   963篇
口腔科学   309篇
临床医学   378篇
内科学   1591篇
皮肤病学   187篇
神经病学   564篇
特种医学   287篇
外科学   1312篇
综合类   26篇
一般理论   1篇
预防医学   218篇
眼科学   92篇
药学   355篇
中国医学   16篇
肿瘤学   856篇
  2022年   53篇
  2021年   129篇
  2020年   61篇
  2019年   80篇
  2018年   138篇
  2017年   117篇
  2016年   145篇
  2015年   140篇
  2014年   177篇
  2013年   227篇
  2012年   311篇
  2011年   351篇
  2010年   218篇
  2009年   188篇
  2008年   309篇
  2007年   353篇
  2006年   351篇
  2005年   319篇
  2004年   318篇
  2003年   286篇
  2002年   292篇
  2001年   266篇
  2000年   247篇
  1999年   211篇
  1998年   92篇
  1997年   48篇
  1996年   48篇
  1995年   50篇
  1994年   36篇
  1993年   48篇
  1992年   144篇
  1991年   126篇
  1990年   126篇
  1989年   132篇
  1988年   104篇
  1987年   111篇
  1986年   98篇
  1985年   90篇
  1984年   87篇
  1983年   70篇
  1982年   34篇
  1979年   76篇
  1978年   40篇
  1977年   34篇
  1973年   40篇
  1971年   34篇
  1970年   38篇
  1969年   41篇
  1968年   41篇
  1967年   48篇
排序方式: 共有7389条查询结果,搜索用时 15 毫秒
1.
Eosinophilic dermatosis of hematological malignancy is a paraneoplastic skin eruption associated with chronic lymphocytic leukemia and other B‐cell malignancies. It clinically resembles an insect bite reaction and it can precede the symptoms of the hematological malignancy or be related to a more aggressive course. Different treatments have been proposed, but partial response and recurrence are frequent. Herein, we describe a case of eosinophilic dermatosis associated with mantle cell lymphoma with remission after lenalidomide therapy.  相似文献   
2.
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.  相似文献   
3.
4.
Background In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer strongly influences on the metastases. Our treatment policy has been to conduct hepatic resection for the metastases at an interval of 3 months after colorectal resection. We examined the appropriateness of interval hepatic resection for synchronous hepatic metastasis. Materials and methods The subjects were 164 patients who underwent resection of hepatic metastasis of colorectal cancer (synchronous, 70 patients; metachronous, 94 patients). Background factors for hepatic metastasis and postoperative results were compared for synchronous and metachronous cases. Results The cumulative survival rate for 164 patients at 3, 5, and 10 years postoperatively was 71.9%, 51.8%, and 36.6%, and the post-resection recurrence rate in remnant livers was 26.8%. Interval resection for synchronous hepatic metastases was conducted in 49 cases after a mean interval of 131 days. No difference was seen in postoperative outcome between synchronous and metachronous cases. Conclusion The outcome was similarly favorable in cases of synchronous hepatic metastasis and in cases of metachronous metastasis. Delaying resection allows accurate understanding of the number and location of hepatic metastases, and is beneficial in determining candidates for surgery and in selecting surgical procedure.  相似文献   
5.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
6.
We studied the spatial frequency characteristics in the upper and lower hemiretina using pattern reversal VECPs. The subjects were 56 normal volunteers ranging in age from 14 to 69 years old. The latency of the first major positive component (P100) of VECPs was measured using checker board pattern stimuli under varying conditions of spatial frequency (112', 56', 28', 14', 7'). For the upper hemiretinal stimuli, the P100 peak latency vs spatial frequencies curve reached minimum at 56' approximately 28' and increased at both lower and higher frequencies. For the lower hemiretinal stimuli, this curve shifted towards lower frequencies. The results suggested that the spatial frequency characteristics between the upper and lower hemiretina were different.  相似文献   
7.
The kapurimycins A1, A2 and A3 were revealed to be new antitumor antibiotics with molecular formula of C27H26O9, C26H24O9 and C27H24O9, respectively. The structures of the kapurimycins were determined by NMR spectroscopic analysis. The kapurimycins are new class of polycyclic microbial metabolites having the tetrahydroanthra-gamma-pyrone skeleton and the beta, gamma-unsaturated delta-keto carboxylic acid structure. The individual components of the kapurimycins differ from one another in the side chain at the pyrone ring of the molecule.  相似文献   
8.
9.
Modern surgery for gastric cancer--Japanese perspective.   总被引:1,自引:0,他引:1  
  相似文献   
10.
To achieve prolonged breath-holding, oxygen was administered just before dynamic CT and high resolution lung CT. Oxygen administration has proved to be a supportive means to improve the quality of CT studies.  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