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   936045篇
  免费   67853篇
  国内免费   1370篇
耳鼻咽喉   12997篇
儿科学   24511篇
妇产科学   23270篇
基础医学   133571篇
口腔科学   28335篇
临床医学   80878篇
内科学   184528篇
皮肤病学   19318篇
神经病学   72471篇
特种医学   36974篇
外国民族医学   79篇
外科学   153349篇
综合类   18073篇
现状与发展   1篇
一般理论   234篇
预防医学   61855篇
眼科学   21387篇
药学   73058篇
  3篇
中国医学   2167篇
肿瘤学   58209篇
  2018年   9074篇
  2017年   7113篇
  2016年   7866篇
  2015年   8965篇
  2014年   12125篇
  2013年   17693篇
  2012年   24365篇
  2011年   25379篇
  2010年   15000篇
  2009年   14411篇
  2008年   24911篇
  2007年   25971篇
  2006年   26743篇
  2005年   25725篇
  2004年   24822篇
  2003年   23852篇
  2002年   23428篇
  2001年   54844篇
  2000年   56681篇
  1999年   47082篇
  1998年   10807篇
  1997年   9532篇
  1996年   9669篇
  1995年   8988篇
  1994年   8328篇
  1993年   7629篇
  1992年   35571篇
  1991年   33989篇
  1990年   32809篇
  1989年   31935篇
  1988年   29044篇
  1987年   28319篇
  1986年   26341篇
  1985年   25223篇
  1984年   17868篇
  1983年   15172篇
  1982年   7820篇
  1981年   6784篇
  1979年   15805篇
  1978年   10626篇
  1977年   9073篇
  1976年   7887篇
  1975年   8647篇
  1974年   10494篇
  1973年   9878篇
  1972年   9375篇
  1971年   8869篇
  1970年   8449篇
  1969年   7946篇
  1968年   7217篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
In-flight encounters with hazardous weather represent one of the most significant safety issues in civil aviation operations. Aircrew judgment is often cited as the probable cause of incidents and accidents involving weather, although lack of information is also a factor. The present study examines how information, presented at different times and in different forms, affects the awareness and decision-making behavior of aircrews in a flight simulation study of a recent microburst/windshear incident. In order to examine the influence of enhanced information transfer on aircrew behavior, intracrew communications and approach-to-land decisions were evaluated with conventional ATC communications and with automated cockpit alerting and display of weather information. Results of the study revealed that aircrews provided only with conventional ATC transmissions of weather information had difficulty discriminating conditions conducive to microburst events from less hazardous windshear events. Improved situation awareness for microburst events was found when ground-based convective weather information was provided in real time to aircrews. Avoidance decision-making was found to be less efficient with conventional ATC alert transmissions when compared to the performance of crews provided with a visual display of microburst events. The importance of information transfer on aircrew situation awareness and decision-making in hazardous weather avoidance is discussed.  相似文献   
993.
994.
995.
996.
997.
The presented report is fibrosarcoma arising from renal capsule in a 64-year-old woman. The tumor is very rare and is the 25th case in Japan. The patient visited our hospital with the complaint of macroscopic hematuria for several days. Abdominal examination revealed a painless lump from the left lumbar region to para-median abdomen. A diagnosis of hydronephrosis caused by neoplasma or tuberculosis was considered by CT, AG, etc., and transperitoneal nephrectomy was performed on 6-July-1984. Pathology of the tumor was fibrosarcoma arising from the renal capsule. Three months later, the tumor was growing on the peritoneal surface from the left renal region and she died on Nov. 10, 1984.  相似文献   
998.
Priapism: a refined approach to diagnosis and treatment   总被引:4,自引:0,他引:4  
The recent introduction of intracorporeal injections of papaverine and phentolamine for the diagnosis and treatment of impotence has resulted in an increased incidence of iatrogenic priapism. Based on our research into penile hemodynamics we propose a refined approach to all types of priapism. Intracorporeal blood gas and pressure monitoring should be used to differentiate ischemic (low flow) from nonischemic (high flow) types. Most cases of papaverine-induced or phentolamine-induced priapism will respond to aspiration alone or in combination with intracorporeal instillation of a diluted alpha-adrenergic agent. In spontaneous priapism alpha-adrenergic agents can be tried first if patients have only mild or no ischemia. In patients with severe ischemia stagnant blood should be evacuated and a shunt procedure should be performed to allow metabolic replenishment of tissue. Intracorporeal pressure monitoring will help to determine the size and number of shunts needed to re-establish corporeal circulation.  相似文献   
999.
The technique and use of a percutaneous subclavian vein catheter for haemodialysis in 20 patients are reported. The catheterization procedure carried a very low morbidity, and blood flow rates of 200–250ml/min were achieved through the catheters. Use of this angioaccess saves future possible sites for permanent vascular access. Infectious complications were not encountered. Subclavian vein catheterization is a favourable alternative to external Silastic Teflon shunt.  相似文献   
1000.
Surgery of Dupuytren's disease: a review of the open palm method   总被引:1,自引:0,他引:1  
Experience with 49 cases of Dupuytren's disease treated by the open palm method and followed for an average of 5 years is reported. This method permits excision of the involved fascia while minimizing early postoperative morbidity associated with the surgical management of this condition. There were no cases of wound necrosis, hematoma, or infection with this technique, and all wounds closed spontaneously within 3 to 5 weeks. Long-term follow-up, however, revealed a significant rate of recurrence (32%) and extension (48%), as well as flexion loss at one or more joints in 41% of involved hands. While helpful in the early care of these patients, the open palm method does not modify the long-term results in Dupuytren's disease, which is a pervasive condition without simple surgical solution.  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