首页 | 官方网站   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   1781篇
  免费   138篇
  国内免费   9篇
医药卫生   1928篇
  2023年   9篇
  2022年   21篇
  2021年   41篇
  2020年   35篇
  2019年   45篇
  2018年   51篇
  2017年   40篇
  2016年   48篇
  2015年   57篇
  2014年   81篇
  2013年   129篇
  2012年   170篇
  2011年   145篇
  2010年   86篇
  2009年   71篇
  2008年   115篇
  2007年   124篇
  2006年   113篇
  2005年   114篇
  2004年   81篇
  2003年   65篇
  2002年   53篇
  2001年   16篇
  2000年   13篇
  1999年   17篇
  1998年   16篇
  1997年   9篇
  1996年   10篇
  1995年   15篇
  1994年   12篇
  1993年   10篇
  1992年   9篇
  1991年   9篇
  1990年   11篇
  1989年   9篇
  1988年   9篇
  1987年   7篇
  1986年   5篇
  1985年   5篇
  1983年   3篇
  1982年   6篇
  1979年   5篇
  1978年   3篇
  1977年   3篇
  1974年   2篇
  1973年   3篇
  1969年   4篇
  1968年   3篇
  1967年   3篇
  1966年   3篇
排序方式: 共有1928条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
Background: Intravenous infusion of lidocaine decreases postoperative pain and speeds the return of bowel function. The authors therefore tested the hypothesis that perioperative lidocaine infusion facilitates acute rehabilitation protocol in patients undergoing laparoscopic colectomy.

Methods: Forty patients scheduled to undergo laparoscopic colectomy were randomly allocated to receive intravenous lidocaine (bolus injection of 1.5 mg/kg lidocaine at induction of anesthesia, then a continuous infusion of 2 mg [middle dot] kg-1 [middle dot] h-1 intraoperatively and 1.33 mg [middle dot] kg-1 [middle dot] h-1 for 24 h postoperatively) or an equal volume of saline. All patients received similar intensive postoperative rehabilitation. Postoperative pain scores, opioid consumption, and fatigue scores were measured. Times to first flatus, defecation, and hospital discharge were recorded. Postoperative endocrine (cortisol and catecholamines) and metabolic (leukocytes, C-reactive protein, and glucose) responses were measured for 48 h. Data (presented as median [25-75% interquartile range], lidocaine vs. saline groups) were analyzed using Mann-Whitney tests. P < 0.05 was considered statistically significant.

Results: Patient demographics were similar in the two groups. Times to first flatus (17 [11-24] vs. 28 [25-33] h; P < 0.001), defecation (28 [24-37] vs. 51 [41-70] h; P = 0.001), and hospital discharge (2 [2-3] vs. 3 [3-4] days; P = 0.001) were significantly shorter in patients who received lidocaine. Lidocaine significantly reduced opioid consumption (8 [5-18] vs. 22 [14-36] mg; P = 0.005) and postoperative pain and fatigue scores. In contrast, endocrine and metabolic responses were similar in the two groups.  相似文献   

5.
A case study is presented in which a focal hand dystonia seems to have developed in the right hand of a classical guitarist as a result of a neuromuscular peripheral defect caused by trauma. The trauma was a near total perforation of the first web space by a splinter. Healing was uneventful without apparent functional complications. Two years later the patient noticed difficulties in extending the index in playing, for which he received various unsuccessful treatments during seven years. However, we found more severe dystonic symptoms (cocontractions) in the thumb than in the index during playing, which correlated with an undiagnosed insufficiency in the flexor pollicis brevis (FPB). This defect allowed proposing a biomechanical analysis of compensations for diminished thumb control in playing, which would explain the dysfunction in the index in playing as overcompensation for the thumb problem. If this analysis is correct, the etiology of the case can be traced back to underlying multiarticular control problems in the thumb caused by an insufficient FPB. This defect was considered irrepairable. It was concluded that even with knowledge of the underlying cause, a potentially successful treatment of the dystonia might not exist in this case. The case would demonstrate that task-specific hand dystonias can arise as overcompensations for (peripheral) neuro-musculoskeletal defects. The case is illustrated by videos of playing and functional thumb tests.  相似文献   
6.
A method for producing carrier free 66Ga (T1/2:9.4h; +) by 4He bombardment of natural copper targets is presented. 66Ga is formed by means of the 63Cu (4He, n) 66Ga reaction. Production yields are given in the 17.5 to 8 MeV 4He energy range. Chemical purification of 66Ga from the copper target is described. The only radionuclidic impurity found in the final product was 67Ga. Albumin colloids from commercially available kits designed for use with 99mTc could easily be labeled with 66Ga and employed for studies of the lymphatic system by positron emission tomography.  相似文献   
7.
Transient receptor potential (TRP) channels provide an enormous variability of Ca(2+) influx mechanisms triggered by a wide range of stimuli. In this review, we discuss the activation properties of the Ca(2+)- and Mg(2+)-permeable TRP channel of the vanilloid subfamily TRPV4. This channel is activated by various physical and chemical stimuli, such as cell swelling, heat, phorbols and, probably, by endogenous ligands, which are able to induce Ca(2+) entry. Not much is known about the regulation of this channel. We will refer only to a mechanism of Ca(2+)-dependent inhibition of TRPV4. Possible functional roles of this channel will be correlated with its observed expression pattern. Finally, we discuss the structural determinants of TRPV4 channel function.  相似文献   
8.
9.
10.
Prior to intracytoplasmic sperm injection (ICSI), seminal fluid is currently washed out from the ejaculated semen and further sperm selection is carried out by a discontinuous Percoll gradient. Possible deleterious effects from the sperm-separating substance Percoll on sperm function or embryo cleavage after in-vitro fertilization (IVF) have, to our knowledge, not yet been reported and the use of Percoll has been widely accepted in IVF. In this study, we examined whether the omission of the Percoll step in the sperm preparation has any influence on the outcome of the ICSI procedure. Two methods of sperm preparation for ICSI were compared in a controlled study on sibling oocytes: washing the semen sample once, followed by a Percoll gradient centrifugation versus washing the sperm sample twice without a Percoll gradient centrifugation. The mean fertilization rates were similar for the two sperm preparation methods: 78.2 +/- 21.4 and 75.0 +/- 24.1% respectively of the intact oocytes displaying two pronuclei. Cleavage rates did not differ statistically between the two groups. Whereas in both groups similar percentages of excellent, good and poor quality embryos were obtained, the percentage of fair quality embryos was significantly higher in the group without Percoll (16.3 +/- 20.1 versus 9.1 +/- 15.7%). However, no statistical differences were observed in either the percentage of transferable embryos or in the percentage of embryos actually transferred or frozen in the two groups. In conclusion, spermatozoa from ejaculates that are washed out from the seminal fluid without any further selection can be used for ICSI without any adverse effect on fertilization and embryo cleavage.   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-23

京公网安备 11010802026262号