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   9844篇
  免费   507篇
  国内免费   138篇
耳鼻咽喉   246篇
儿科学   333篇
妇产科学   311篇
基础医学   1145篇
口腔科学   378篇
临床医学   780篇
内科学   1289篇
皮肤病学   273篇
神经病学   625篇
特种医学   645篇
外科学   1737篇
综合类   364篇
一般理论   1篇
预防医学   640篇
眼科学   296篇
药学   639篇
  1篇
中国医学   139篇
肿瘤学   647篇
  2023年   64篇
  2022年   117篇
  2021年   160篇
  2020年   120篇
  2019年   121篇
  2018年   196篇
  2017年   158篇
  2016年   261篇
  2015年   277篇
  2014年   280篇
  2013年   391篇
  2012年   399篇
  2011年   560篇
  2010年   448篇
  2009年   421篇
  2008年   412篇
  2007年   422篇
  2006年   395篇
  2005年   433篇
  2004年   541篇
  2003年   419篇
  2002年   359篇
  2001年   284篇
  2000年   276篇
  1999年   293篇
  1998年   174篇
  1997年   148篇
  1996年   128篇
  1995年   85篇
  1994年   66篇
  1993年   79篇
  1992年   113篇
  1991年   88篇
  1990年   77篇
  1989年   96篇
  1988年   76篇
  1987年   73篇
  1986年   77篇
  1985年   68篇
  1984年   52篇
  1983年   61篇
  1982年   48篇
  1981年   56篇
  1979年   40篇
  1978年   45篇
  1975年   46篇
  1974年   48篇
  1973年   47篇
  1932年   36篇
  1926年   34篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
31.
桥本氏病手术治疗45例临床分析   总被引:2,自引:1,他引:1  
本文分析45例桥本氏病诊断和手术治疗的经验教训。本病合并其它甲状腺外科疾病 诊断困难,手术方式要慎重选择。术中常规冰冻快速活检,可帮助鉴别诊断和指导术式选择。  相似文献   
32.
33.
34.
35.
A diary method using household measures was employed to obtain dietary records in a large national prospective survey and a computer program, DIDO (Diet In Data Out), was designed for direct entry of the diaries. The accuracy of this computerized coding system was examined alongside that of the manual coding used for a similar diary in a previous wave, 7 years earlier, of the same survey. Accuracy was assessed by analysis of the errors in the coded and checked records by stringent re-checking of nominal 2% random subsamples of the diet diaries coded by each method. The mean time to code and check each of the 2086 7-day records in the whole survey using DIDO was 58 minutes (SD 30) compared with reported results of 1–4 hours for manual methods. The mean error rate of computerized coding and checking with DIDO was 2.3% (SD 2.1; range 0–8.9) per diary in the subsample. Correcting these mistakes made insignificant changes to the calculated mean energy and nutrient intakes for the subsample. The percentage of individuals changing to an adjacent third of nutrient distribution after correcting unambiguous errors ranged from none (for alcohol) to 11% (for carbohydrate and calcium intake). The mean error rate on a similar subsample of diaries from the earlier survey which had been coded manually was significantly higher at 5.9% (SD 4.1; range 0–17) per diary. Emphasis is laid on the importance, in coding, of dealing with ambiguities in the subjects' records, since this can affect the accuracy and the precision of the nutrient results obtained. We conclude that the DIDO coding method has the advantages of greater accuracy, speed, consistency and efficient data handling, and affords greater data accessibility for checking, compared with manual systems.  相似文献   
36.
Objective: To establish a prostatic hyperplasia model with beagle dogs. Methods: Twenty-four male beagle dogs, 2 years of age, were divided into the treatment and control groups at random and were administrated testosterone propionate (TP) i.m. two months after castration. Three treatment groups were set with the doses of TP at 0.8 mg/kg, 2.5 mg/kg and 7.5 mg/kg, respectively, and the control was given the same volume of vehicle. Two months later, half of the animals were killed and sera samples were obtained. The wet weight and volume of prostate were measured. The dihydro testosterone (DHT) level of the serum and prostate were determined with the commercial radioimmunoassay (RIA) kit. The prostate was sectioned, fixed and stained with hematoxylin and eosin. Pictures were taken with a digital camera under the microscope and were analyzed with a computer for the epithelial cell height and the acinar luminal area with micro image analysis software. The prostate volume was measured with ultrasonic diagnost  相似文献   
37.
38.
39.
用3H-甘露糖标记7721人肝癌细胞表面糖蛋白的N-糖链,经提取和去唾液酸后,用ConA和DSA亲和柱顺序层析将3H-标记的N-糖链分成4个类型和天线数不同的组分来研究维甲酸(RA)对细胞表面N-糖链的影响。结果:10μmol/LRA处理细胞3~5d后,可使C2C2二天线复杂型N-糖链增加,而高甘露糖型及三、四天线,特别是带有C2,6分支结构的复杂型H-糖链减少。用LCA亲和柱还证明二天线糖链中的核心岩藻糖也减少。进一步发现上述改变的酶学机制是RA降低N-乙酰氨基萄葡糖转移酶V和α-1,6-核心岩藻糖转移酶的活力。结论:BA通过改变某些糖基转移酶活力而改变细胞表面糖链结构,这可能是RA使7721细胞诱导分化的机理之-。  相似文献   
40.
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus, it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule. Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus.  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