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   10284篇
  免费   515篇
  国内免费   67篇
耳鼻咽喉   83篇
儿科学   265篇
妇产科学   172篇
基础医学   1349篇
口腔科学   313篇
临床医学   639篇
内科学   2608篇
皮肤病学   108篇
神经病学   578篇
特种医学   325篇
外科学   1963篇
综合类   33篇
预防医学   251篇
眼科学   221篇
药学   768篇
中国医学   39篇
肿瘤学   1151篇
  2023年   49篇
  2022年   42篇
  2021年   188篇
  2020年   114篇
  2019年   178篇
  2018年   214篇
  2017年   168篇
  2016年   187篇
  2015年   214篇
  2014年   273篇
  2013年   315篇
  2012年   460篇
  2011年   544篇
  2010年   290篇
  2009年   290篇
  2008年   483篇
  2007年   544篇
  2006年   455篇
  2005年   518篇
  2004年   524篇
  2003年   468篇
  2002年   489篇
  2001年   330篇
  2000年   297篇
  1999年   265篇
  1998年   109篇
  1997年   87篇
  1996年   93篇
  1995年   91篇
  1994年   78篇
  1993年   76篇
  1992年   247篇
  1991年   222篇
  1990年   212篇
  1989年   214篇
  1988年   174篇
  1987年   168篇
  1986年   173篇
  1985年   130篇
  1984年   99篇
  1983年   98篇
  1982年   59篇
  1979年   68篇
  1978年   54篇
  1977年   45篇
  1975年   40篇
  1974年   51篇
  1973年   47篇
  1972年   45篇
  1971年   40篇
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
1.
2.
3.

Background

Controversy continues as to whether single-incision laparoscopic cholecystectomy, with the somewhat larger incision at the umbilicus, may lead to a worse postoperative quality of life and more pain compared with the more classic 4-port laparoscopic cholecystectomy. The aim of this study was to compare single-incision and 4-port laparoscopic cholecystectomy from the perspective of quality of life.

Methods

This study was a multicenter, parallel-group, open-label, randomized clinical trial. A total of 120 patients who were scheduled to undergo elective cholecystectomy were randomly assigned 1:1 into the single-incision laparoscopic cholecystectomy or the 4-port laparoscopic cholecystectomy group and then assessed continuously for 2 weeks during the postoperative period. The primary outcome was quality of life, defined as the time to resume normal daily activities. Postoperative pain was also assessed. To explore the heterogeneity of treatment effects, we assessed the interactions of sex, age, and working status on recovery time.

Results

A total of 58 patients in the single-incision group and 53 in the 4-port group (n?=?111, 47 male, mean age 57 years) were analyzed. The mean time to resume daily activities was 10.2 days and 8.8 days, respectively, for single-incision and 4-port laparoscopic cholecystectomy (95% confidence interval –0.4 to 3.2, P?=?.12). Similarly, the time to relief from postoperative pain did not differ significantly between the groups. Statistically insignificant but qualitative interactions were noted; in the subgroups of women, full-time workers, and patients younger than 60 years, recovery tended to be slower after single-incision laparoscopic cholecystectomy.

Conclusion

Postoperative quality of life did not differ substantially between single-incision laparoscopic cholecystectomy and 4-port laparoscopic cholecystectomy. Patients younger than 60 years, women, and full-time workers tended to have a somewhat slower recovery after single-incision laparoscopic cholecystectomy.  相似文献   
4.
5.
6.
7.
  1. In this study, total body clearance (CLt), volume of distribution at steady state (Vss) and plasma concentration–time profiles in humans of model compounds were predicted using chimeric mice with humanized livers.

  2. On the basis of assumption that unbound intrinsic clearance (CLUint) per liver weight in chimeric mice was equal to those in humans, CLt were predicted by substituting human liver blood flow and liver weights in well-stirred model. Vss were predicted by Rodgers equation using scaling factors of tissue-plasma concentration ratios (SFKp) in chimeric mice estimated from a difference between the observed and predicted Vss. These physiological approaches showed high prediction accuracy for CLt and Vss values in humans.

  3. We compared the predictability of CLt and Vss determined by the physiologically based predictive approach using chimeric mice with those from predictive methods reported by Pharmaceutical Research Manufacturers of America. The physiological approach using chimeric mice indicated the best prediction accuracy in each predictive method.

  4. Simulation of human plasma concentration–time profiles were generally successful with physiologically based pharmacokinetic (PBPK) model incorporating CLUint and SFKp obtained from chimeric mice.

  5. Combined application of chimeric mice and PBPK modeling is effective for prediction of human PK in various compounds.

  相似文献   
8.
The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
9.
10.
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