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   2890篇
  免费   315篇
  国内免费   52篇
耳鼻咽喉   20篇
儿科学   142篇
妇产科学   27篇
基础医学   356篇
口腔科学   134篇
临床医学   322篇
内科学   700篇
皮肤病学   113篇
神经病学   140篇
特种医学   219篇
外科学   387篇
综合类   126篇
预防医学   167篇
眼科学   77篇
药学   168篇
中国医学   9篇
肿瘤学   150篇
  2023年   23篇
  2022年   23篇
  2021年   61篇
  2020年   33篇
  2019年   39篇
  2018年   57篇
  2017年   66篇
  2016年   63篇
  2015年   58篇
  2014年   107篇
  2013年   126篇
  2012年   91篇
  2011年   101篇
  2010年   106篇
  2009年   108篇
  2008年   104篇
  2007年   152篇
  2006年   108篇
  2005年   99篇
  2004年   106篇
  2003年   82篇
  2002年   84篇
  2001年   90篇
  2000年   71篇
  1999年   87篇
  1998年   104篇
  1997年   88篇
  1996年   78篇
  1995年   64篇
  1994年   68篇
  1993年   62篇
  1992年   79篇
  1991年   61篇
  1990年   58篇
  1989年   71篇
  1988年   54篇
  1987年   53篇
  1986年   59篇
  1985年   54篇
  1984年   36篇
  1983年   30篇
  1982年   17篇
  1981年   12篇
  1980年   16篇
  1979年   26篇
  1978年   11篇
  1977年   20篇
  1976年   16篇
  1975年   13篇
  1970年   9篇
排序方式: 共有3257条查询结果,搜索用时 0 毫秒
1.
Haaga  JR; Beale  SM 《Radiology》1986,161(3):829-830
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6).  相似文献   
2.
3.
A technique is described that provides adequate coverage for rib grafts used in reconstruction of the atrophic mandible. The flaps are highly vascular and thick because of the fibrous capsule that forms around the tissue expander. A one-stage expansion technique is used that reduces the total time needed for reconstruction.  相似文献   
4.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响.  相似文献   
5.
OBJECTIVE: To determine whether bacterial cultures of the wounds of patients undergoing clean orthopedic surgery would help predict infection. METHODS: During 1 year, 1,256 cultures were performed for 1,102 patients who underwent clean orthopedic surgery. Results were analyzed to evaluate their ability to predict postoperative infection. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the cultures were 38%, 92%, 7%, and 99%, respectively. CONCLUSIONS: Cultures performed during clean orthopedic surgery were not useful for predicting postoperative infection.  相似文献   
6.
Reduction mammaplasty by central pedicle flap with short submammary scar   总被引:2,自引:0,他引:2  
Reduction mammaplasty was performed in 30 patients by combining the central pedicle flap method with the short submammary scar (3-S) technique to avoid the common drawbacks of currently popular dermoglandular procedures. Reduction was accomplished by using perforating vascular branches from the pectoralis major muscle and its fascia supplying the nipple and breast parenchyme instead of the subdermal plexus. The central vascular pedicle supplying the nipple-areola complex was preserved. Only the periphery of the breast parenchyme was resected circumferentially, with the exception of the inferolateral portion, so as not to injure the sensory nerve. The remaining breast parenchyme was preserved in an inverted cone shape. The nipple-areola complex was safely transposed with great freedom, and the amount of resection was accurately adjusted for symmetry. No cases of nipple-areola complex sensory change occurred postoperatively, and lactation is possible because of preservation of the lactiferous ducts. The length of postoperative scars was reduced by using the short submammary scar technique. We believe this combined method is ideal in patients requiring resections ranging from 200 to 600 g per breast with good skin elasticity and moderate degree of ptosis.Presented at the Sixth Asian Pacific Congress of the International Confederation for Plastic and Reconstructive Surgery, in Seoul, Korea, October 1993.  相似文献   
7.
8.
H Lew  J Jerger 《Ear and hearing》1991,12(5):365-367
This study was designed to investigate the extent to which continuous speech competition, in sentence identification paradigm, produces linguistic interference over and above acoustic masking. We evaluated performance on the Synthetic Sentence Identification (SSI) test in 24 bilingual speakers of English and Spanish under four experimental conditions: (1) target and competition both in English, (2) target and competition both in Spanish, (3) target in English, competition in Spanish, and (4) target in Spanish, competition in English. After controlling for the effects of acoustic masking, results showed significantly better performance in conditions when target and competition were in different languages (interlingual interference) than when target and competition were in the same language (intralingual interference). The difference in performance is attributed to the effects of greater linguistic interference when target and competition were in the same language.  相似文献   
9.
10.
Several potentially irreversible ligands (i.e., wash-resistant binding inhibitors) for the cocaine receptor site on the dopamine transporter, derived from (-)-cocaine or 3 beta-phenyltropan-2 beta-carboxylic acid methyl ester (WIN 35,065-2), were prepared and shown to produce wash-resistant inhibition of [3H]-3 beta-(p-fluorophenyl)tropan-2 beta-carboxylic acid methyl ester ([3H]WIN 35,428) binding. All the compounds prepared had the same absolute configuration as cocaine; they include analogues possessing chemically reactive groups such as the isothiocyanato and bromoacetamido as well as photoactive azido groups. The potentially irreversible ligands, as well as all the intermediates prepared in this study, were evaluated for their ability to inhibit the binding of [3H]WIN 35,428 in coincubation experiments. Of the potentially irreversible ligands, 3 beta-(p-chlorophenyl)tropan-2 beta-carboxylic acid 2-[p-(bromoacetamido)phenyl]ethyl ester (6c) had the highest apparent potency. The potentially irreversible ligands were also preincubated, and inhibition of [3H]WIN 35,428 binding was determined both before and after washing the ligand-exposed tissues. The most effective ligands in this regard were 3 beta-(3-iodo-4-azidophenyl)tropan-2 beta-carboxylic acid methyl ester (5) and 3 beta-(p-chlorophenyl)tropan-2 beta-carboxylic acid 2-(3-iodo-4-azidophenyl)ethyl ester (6d). The structure-activity relationships of these data are discussed.  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