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   930808篇
  免费   67630篇
  国内免费   1343篇
耳鼻咽喉   12959篇
儿科学   24365篇
妇产科学   23239篇
基础医学   132969篇
口腔科学   28277篇
临床医学   80520篇
内科学   183239篇
皮肤病学   19275篇
神经病学   72206篇
特种医学   36832篇
外国民族医学   79篇
外科学   152198篇
综合类   18056篇
现状与发展   1篇
一般理论   234篇
预防医学   61684篇
眼科学   21313篇
药学   72533篇
  3篇
中国医学   2162篇
肿瘤学   57637篇
  2018年   8967篇
  2017年   7028篇
  2016年   7765篇
  2015年   8863篇
  2014年   11995篇
  2013年   17512篇
  2012年   24096篇
  2011年   25065篇
  2010年   14821篇
  2009年   14289篇
  2008年   24627篇
  2007年   25705篇
  2006年   26505篇
  2005年   25447篇
  2004年   24566篇
  2003年   23618篇
  2002年   23167篇
  2001年   54766篇
  2000年   56578篇
  1999年   46966篇
  1998年   10741篇
  1997年   9476篇
  1996年   9602篇
  1995年   8930篇
  1994年   8285篇
  1993年   7601篇
  1992年   35503篇
  1991年   33924篇
  1990年   32751篇
  1989年   31884篇
  1988年   29006篇
  1987年   28261篇
  1986年   26299篇
  1985年   25161篇
  1984年   17846篇
  1983年   15156篇
  1982年   7805篇
  1981年   6779篇
  1979年   15795篇
  1978年   10615篇
  1977年   9063篇
  1976年   7881篇
  1975年   8634篇
  1974年   10475篇
  1973年   9870篇
  1972年   9367篇
  1971年   8860篇
  1970年   8431篇
  1969年   7932篇
  1968年   7201篇
排序方式: 共有10000条查询结果,搜索用时 468 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