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   124315篇
  免费   6420篇
  国内免费   172篇
耳鼻咽喉   1852篇
儿科学   5536篇
妇产科学   4150篇
基础医学   17296篇
口腔科学   3051篇
临床医学   9121篇
内科学   23605篇
皮肤病学   3461篇
神经病学   9879篇
特种医学   5427篇
外国民族医学   32篇
外科学   20226篇
综合类   1649篇
一般理论   32篇
预防医学   6427篇
眼科学   3505篇
药学   8472篇
中国医学   350篇
肿瘤学   6836篇
  2018年   1041篇
  2017年   891篇
  2016年   1216篇
  2015年   1344篇
  2014年   1794篇
  2013年   2650篇
  2012年   3477篇
  2011年   3525篇
  2010年   2187篇
  2009年   2116篇
  2008年   3580篇
  2007年   3792篇
  2006年   3998篇
  2005年   4102篇
  2004年   4041篇
  2003年   3896篇
  2002年   3802篇
  2001年   7277篇
  2000年   7231篇
  1999年   6101篇
  1998年   1722篇
  1997年   1651篇
  1996年   1420篇
  1995年   1264篇
  1994年   1156篇
  1993年   1189篇
  1992年   3956篇
  1991年   3747篇
  1990年   3732篇
  1989年   3502篇
  1988年   3122篇
  1987年   3043篇
  1986年   2933篇
  1985年   2756篇
  1984年   2053篇
  1983年   1684篇
  1982年   986篇
  1981年   972篇
  1980年   799篇
  1979年   1888篇
  1978年   1434篇
  1977年   1162篇
  1976年   983篇
  1975年   1234篇
  1974年   1276篇
  1973年   1261篇
  1972年   1104篇
  1971年   1033篇
  1970年   937篇
  1969年   830篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
After lindane administration in daily doses of 0.1 LD50 for one month (total dose 2.0 LD50) changes in the erythrocytes were found persisting for up to 4 months after withdrawal of the pesticide. A significant increase in the number of echinocytes, a greater per cent of reticulocytes, significantly raised level of denatured haemoglobin, and an increased number of erythrocytes of higher sensitivity to oxidating factors in relation to control group was observed.  相似文献   
102.
103.
104.
105.
106.
107.
U Chikte  S Naidoo 《SADJ》2000,55(12):661-662
  相似文献   
108.
The ability of human bladder tissue extracts to cleave 14C-labelled globin in the absence and in the presence of plasminogen was assayed to quantify non-specific protease and plasminogen activator (PA) activity, respectively. In normal human bladder tissue the non-specific protease activity was approximately 2-fold higher than in tissue samples obtained from transitional cell carcinoma of the bladder (TCC). In contrast, PA activity was almost 4-fold higher in TCC than in normal transition cell epithelium. Acid-treated urine from 19 patients with TCC of the bladder exhibited significantly higher levels of plasminogen activator activity than similarly treated urine from controls. These results indicate that malignant transformation of the bladder epithelial tissue results in elevated levels of PA in the tissue and in urine. Further studies are needed to assess the potential of PA determination in the management of bladder cancer patients.  相似文献   
109.
Osteopenia of the tibia and femur caused by an external fixator in the tibia was studied in 14 rabbits. Eight rabbits were treated with a complete unilateral external fixator in one tibia, whereas the other tibia served as control. The other 6 animals had one leg operated on with inserting of all the pins but without the frame. This technique was chosen to compare osteopenia caused by stress protection and the effect of the pins. After 6 weeks, we found a 7 percent reduction in the bone mineral content in the tibial diaphyseal segment between the pins of the external fixator and no bone loss in the tibia that were operated on with only pins. In the femurs, there was a smaller decrease in the bone mineral content: respectively 3.2 percent (complete frame) and 2.9 percent (only pins). On all the operated on tibiae, there was an increase in the bone mineral content around the pins both proximally and distally.  相似文献   
110.
The pathophysiology, diagnosis, and treatment of diabetic gastroparesis are reviewed, and the mechanisms of action, pharmacokinetics, clinical efficacy, adverse effects, and dosage of metoclopramide, domperidone, and cisapride are described. Diabetic gastroparesis is a state of delayed gastric emptying that reportedly affects 20-30% of diabetic patients. Symptoms include nausea, early satiety, postprandial bloating and fullness, and vomiting. Diabetic gastroparesis has been managed most successfully with drugs that stimulate gastric emptying. Of the three agents studied--metoclopramide, domperidone, and cisapride--only metoclopramide is commercially available in the United States. The clinical efficacy of metoclopramide, domperidone, and cisapride has been well documented in several placebo-controlled trials. Metoclopramide effectively decreases mean gastric emptying time, although tolerance to this stimulation of gastric emptying may develop with long-term therapy. However, symptomatic relief persists with long-term therapy because of metoclopramide's antiemetic properties. Domperidone, which has also been shown to stimulate gastric motility and to possess antiemetic properties, improves symptoms in patients suffering from diabetic gastroparesis. Cisapride appears to have continued beneficial effects on gastric motility with long-term therapy. All three agents have favorable adverse-effect profiles. Although metoclopramide is currently the first-line agent for the management of gastroparesis, domperidone and cisapride both possess properties that may make them useful alternatives in patients who are unresponsive to or cannot tolerate metoclopramide therapy.  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