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   398098篇
  免费   25958篇
  国内免费   2982篇
耳鼻咽喉   5311篇
儿科学   9334篇
妇产科学   10383篇
基础医学   55515篇
口腔科学   12134篇
临床医学   31308篇
内科学   81650篇
皮肤病学   8941篇
神经病学   28453篇
特种医学   14598篇
外国民族医学   87篇
外科学   63311篇
综合类   10740篇
现状与发展   1篇
一般理论   65篇
预防医学   18807篇
眼科学   10485篇
药学   32922篇
  6篇
中国医学   2492篇
肿瘤学   30495篇
  2021年   3015篇
  2019年   3021篇
  2018年   4881篇
  2017年   3721篇
  2016年   3869篇
  2015年   4429篇
  2014年   6280篇
  2013年   8143篇
  2012年   11116篇
  2011年   11350篇
  2010年   6856篇
  2009年   6372篇
  2008年   10367篇
  2007年   11225篇
  2006年   11075篇
  2005年   10081篇
  2004年   9508篇
  2003年   9242篇
  2002年   8883篇
  2001年   28829篇
  2000年   29362篇
  1999年   24194篇
  1998年   5396篇
  1997年   4463篇
  1996年   4017篇
  1995年   3653篇
  1994年   3245篇
  1993年   2995篇
  1992年   16397篇
  1991年   15183篇
  1990年   14484篇
  1989年   14328篇
  1988年   12857篇
  1987年   12358篇
  1986年   11339篇
  1985年   10585篇
  1984年   7133篇
  1983年   5801篇
  1982年   2842篇
  1979年   5656篇
  1978年   3463篇
  1977年   3074篇
  1976年   2339篇
  1975年   2770篇
  1974年   3194篇
  1973年   2990篇
  1972年   2945篇
  1971年   2912篇
  1970年   2611篇
  1969年   2620篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
43.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
44.
BackgroundWomen suffering from kidney disease are more prone to fertility problems, due to uremia. Fortunately, their fertility rate increases dramatically after renal transplantation. This study analyzes the predictors/risk factors of successful pregnancy with live birth outcome while presenting an overview of the 7-year experience of a single center.MethodsThis retrospective cohort study includes 239 women of reproductive age (18–40 years) who underwent renal transplantation in a tertiary Turkish clinic between October 1, 2011, and August 24, 2017. The subjects were invited to take part in a survey questioning their obstetric characteristics and they were assessed in 2 groups: fertile and infertile. Multivariable linear regression analysis was conducted to determine the predictors of a successful pregnancy.ResultsThirty-five 35 patients wished to become pregnant: 12 got pregnant spontaneously, while 21 failed to become pregnant (spontaneously). The mean age of the patients at the survey was 34 ± 7. Regular menstrual cycles after renal transplantation, tacrolimus-mycophenolate mofetil maintenance protocol, and age at transplantation were found to be predictors of spontaneous pregnancy. The duration of peritoneal dialysis was significantly longer in the infertile group (48 vs 12 months).ConclusionEnd-stage renal disease's negative impacts, including menstrual abnormality and fertility problems, can be overcome by successful kidney transplantation with appropriate immunosuppression. Minimizing the duration of peritoneal dialysis, particularly in patients who desire future fertility, may be accepted as a logical management strategy.  相似文献   
45.
46.
47.
48.
49.
50.
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