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   9112篇
  免费   487篇
  国内免费   73篇
耳鼻咽喉   125篇
儿科学   235篇
妇产科学   207篇
基础医学   1089篇
口腔科学   193篇
临床医学   693篇
内科学   2228篇
皮肤病学   178篇
神经病学   640篇
特种医学   433篇
外科学   1304篇
综合类   36篇
一般理论   1篇
预防医学   668篇
眼科学   341篇
药学   571篇
中国医学   9篇
肿瘤学   721篇
  2023年   46篇
  2022年   61篇
  2021年   188篇
  2020年   110篇
  2019年   165篇
  2018年   208篇
  2017年   175篇
  2016年   170篇
  2015年   213篇
  2014年   255篇
  2013年   335篇
  2012年   541篇
  2011年   553篇
  2010年   299篇
  2009年   300篇
  2008年   563篇
  2007年   576篇
  2006年   565篇
  2005年   521篇
  2004年   550篇
  2003年   436篇
  2002年   454篇
  2001年   267篇
  2000年   221篇
  1999年   203篇
  1998年   104篇
  1997年   80篇
  1996年   102篇
  1995年   59篇
  1994年   54篇
  1993年   41篇
  1992年   125篇
  1991年   102篇
  1990年   96篇
  1989年   95篇
  1988年   109篇
  1987年   69篇
  1986年   68篇
  1985年   65篇
  1984年   68篇
  1983年   32篇
  1982年   28篇
  1981年   29篇
  1979年   31篇
  1978年   38篇
  1976年   25篇
  1975年   23篇
  1974年   25篇
  1973年   39篇
  1968年   20篇
排序方式: 共有9672条查询结果,搜索用时 17 毫秒
1.
2.
3.
4.
5.
6.
Introduction

Visible light spectroscopy (VLS) represents a sensitive, non-invasive method to quantify tissue oxygen levels and detect hypoxemia. The aim of this study was to assess the microperfusion patterns of the gastric pouch during laparoscopic Roux-en-Y gastric bypass (LRYGB) using the VLS technique.

Methods

Twenty patients were enrolled. Tissue oxygenation (StO2%) measurements were performed at three different localizations of the gastric wall, prior and after the creation of the gastric pouch, and after the creation of the gastro-jejunostomy.

Results

Prior to the creation of the gastric pouch, the lowest StO2% levels were observed at the level of the distal esophagus with a median StO2% of 43 (IQR 40.8–49.5). After the creation of the gastric pouch and after the creation of the gastro-jejunostomy, the lowest StO2% levels were recorded at the level of the His angle with median values of 29% (IQR 20–38.5) and 34.5% (IQR 19–39), respectively. The highest mean StO2 reduction was recorded at the level of the His angle after the creation of the gastric pouch, and it was 18.3% (SD ± 18.1%, p < 0.001). A reduction of StO2% was recorded at all localizations after the formation of the gastro-jejunostomy compared to the beginning of the operation, but the mean differences of the StO2% levels were statistically significant only at the resection line of the pouch and at the His angle (p = 0.044 and p < 0.001, respectively).

Conclusion

Gastric pouch demonstrates reduction of StO2% during LRYGB. VLS is a useful technique to assess microperfusion patterns of the stomach during LRYGB.

Graphical abstract
  相似文献   
7.
Spinal cord stimulation (SCS) is widely used for pain relief in patients with failed back surgery syndrome (FBSS), and muscle weakness is a common finding in patients with chronic pain. We present here a single case report of a 47‐year‐old woman, who, after SCS for FBSS, had continuous improvement in lower leg muscle strength and gait, but only transient and minimal pain relief. To the authors’ knowledge, this is only the second published case report of significant improvement in “motor” function, independent of the analgesic effect following SCS in FBSS. If SCS, in fact, does improve muscle strength, new strategies for the management of patients with chronic pain might be opened up. Further studies are needed to verify this hypothesis.  相似文献   
8.
9.
Preparation of blood specimens is a major bottleneck in the laboratory throughput. Reliable strategies for reducing the time required for specimen processing without affecting quality should be acknowledged, especially for laboratories performing stat analyses. The present investigation was planned to establish a minimal suitable centrifuge time for primary samples collected for routine coagulation testing. Five sequential primary vacuum tubes containing 0.109 mol/l buffered trisodium citrate were collected from 10 volunteers and were immediately centrifuged on a conventional centrifuge at 1500 x g, at room temperature for 1, 2, 5, 10 and 15 min, respectively. Hematological and routine coagulation testing, including prothrombin time, activated partial thromboplastin time and fibrinogen, were performed. The centrifugation time was inversely associated with residual blood cell elements in plasma, especially platelets. Statistically significant variations from the reference 15-min centrifuge specimens were observed for fibrinogen in samples centrifuged for 5 min at most and for the activated partial thromboplastin time in samples centrifuged for 2 min at most. Meaningful biases related to the desirable bias were observed for fibrinogen in samples centrifuged for 2 min at most, and for the activated partial thromboplastin time in samples centrifuged for 1 min at most. According to our experimental conditions, a 5-10 min centrifuge time at 1500 x g may be suitable for primary tubes collected for routine coagulation testing.  相似文献   
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