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   332965篇
  免费   49925篇
  国内免费   16574篇
耳鼻咽喉   4410篇
儿科学   5500篇
妇产科学   5936篇
基础医学   31245篇
口腔科学   8853篇
临床医学   58582篇
内科学   59669篇
皮肤病学   5853篇
神经病学   26059篇
特种医学   12004篇
外国民族医学   138篇
外科学   40749篇
综合类   35729篇
现状与发展   94篇
一般理论   55篇
预防医学   29050篇
眼科学   8997篇
药学   24948篇
  194篇
中国医学   12401篇
肿瘤学   28998篇
  2024年   1426篇
  2023年   8531篇
  2022年   10536篇
  2021年   14805篇
  2020年   14054篇
  2019年   10170篇
  2018年   15357篇
  2017年   14703篇
  2016年   14827篇
  2015年   18541篇
  2014年   23435篇
  2013年   23560篇
  2012年   21277篇
  2011年   23113篇
  2010年   18043篇
  2009年   17852篇
  2008年   15751篇
  2007年   14773篇
  2006年   15935篇
  2005年   14411篇
  2004年   9357篇
  2003年   8552篇
  2002年   7261篇
  2001年   6813篇
  2000年   6495篇
  1999年   7398篇
  1998年   5687篇
  1997年   5441篇
  1996年   4794篇
  1995年   4329篇
  1994年   3249篇
  1993年   2304篇
  1992年   2645篇
  1991年   2235篇
  1990年   1804篇
  1989年   1607篇
  1988年   1526篇
  1987年   1278篇
  1986年   1092篇
  1985年   825篇
  1984年   595篇
  1983年   547篇
  1982年   384篇
  1981年   346篇
  1980年   236篇
  1979年   212篇
  1978年   171篇
  1977年   169篇
  1975年   118篇
  1974年   133篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
61.
The authors reviewed the radiographic manifestations of 17 cases of parosteal osteosarcoma, with pathologic correlation in 15. There were two types of parosteal osteosarcoma radiologically. The majority of cases were type I with uniformly dense masses which had regular borders. They often adhered to the cortex and showed no evidence of soft-tissue invasion which correlated with low-grade pathologic malignancy and a relatively benign clinical course. Type II involved the bone, soft-tissue and the medullary cavity. These lesions were poorly differentiated and frequently accompanied by metastatic lesions.
  相似文献   
62.
63.
Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable.  相似文献   
64.
65.
This study evaluated the safety and efficacy of batroxobin in treating hyperfibrinogenemia for secondary stroke prevention. Patients with ischemic stroke or transient ischemic attack (TIA) were measured for plasma fibrinogen levels. Selected participants had concomitant hyperfibrinogenemia (plasma fibrinogen > or = 3.0 g/l). Patients enrolled between 1 July 2003 and 31 December 2004 were treated with batroxobin; patients enrolled between 1 January 2002 and 30 June 2003 were treated without batroxobin. Batroxobin was administered intermittently via intravenous injection at 3-monthly intervals. Patients in both groups were followed for 1 year. Any cerebrovascular events and suspected adverse events were recorded. In total, 112 ischemic stroke/TIA patients with concomitant hyperfibrinogenemia were enrolled, 52 being treated with batroxobin and 60 without batroxobin. Six patients (11.5%) with batroxobin and 16 patients (26.7%) without batroxobin had recurrent cerebral ischemic events during follow-up. Stroke/TIA recurrence in patients without batroxobin was higher than that in patients with batroxobin (P < 0.05). Two patients with batroxobin and two patients without batroxobin developed hemorrhagic stroke during follow-up. There were five deaths (9.6%) in the batroxobin group, and seven deaths (11.7%) in the nonbatroxobin group during follow-up (P > 0.05). Intermittent intravenous injection of batroxobin can efficiently reduce the risk for stroke/TIA recurrence in patients with concomitant hyperfibrinogenemia.  相似文献   
66.
67.
刘振举 《护理研究》2007,21(12):1108-1109
一般护理记录单是住院病历的一部分,根据卫生部、中医药管理局公布的《病历书写基本规范》(试行)的规定,一般护理记录的定义是:护士根据医嘱和病情对一般病人住院期间护理过程的客观记录,内容包括病人姓名、记录日期和时间、病情观察、护理措施和效果、护士签名。现将护士在一般护理书写中存在认识上的理解偏差分析如下。  相似文献   
68.
The alphavbeta6 integrin is an exclusively epithelial integrin that is highly expressed during fetal development. In adult tissue, alphavbeta6 integrin is expressed during inflammation, carcinogenesis, and in wound healing. We previously reported that alphavbeta6 integrin is highly expressed in poorly healing human wounds and its over-expression is associated with chronic wounds in a mouse model. The objective of this study was to investigate the role of alphavbeta6 integrin in compromised wound healing induced by hydrocortisone treatment or aging by using young and old mice deficient in or overexpressing the beta6 integrin subunit in the epidermis. Untreated aged beta6 integrin-deficient (beta6-/-) animals showed a significant delay in wound healing when compared to their age-matched controls or younger beta6-/- mice. The most significant delay was observed at the stages where granulation tissue deposition was occurring. Hydrocortisone treatment significantly delayed wound healing in wild-type and beta6 integrin-deficient mice in comparison with the untreated controls. However, hydrocortisone treatment in beta6 integrin overexpressing animals did not cause a significant delay in wound healing. The results of this study suggest that alphavbeta6 integrin plays an important role in wound healing in animals compromised by either age or stress mimicked by hydrocortisone.  相似文献   
69.
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