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   124936篇
  免费   9782篇
  国内免费   354篇
耳鼻咽喉   1586篇
儿科学   3289篇
妇产科学   2809篇
基础医学   15864篇
口腔科学   2582篇
临床医学   12757篇
内科学   26061篇
皮肤病学   1307篇
神经病学   11443篇
特种医学   4157篇
外国民族医学   3篇
外科学   20252篇
综合类   2045篇
现状与发展   1篇
一般理论   80篇
预防医学   10725篇
眼科学   3159篇
药学   7962篇
中国医学   154篇
肿瘤学   8836篇
  2022年   692篇
  2021年   1970篇
  2020年   1084篇
  2019年   1964篇
  2018年   2366篇
  2017年   1714篇
  2016年   1860篇
  2015年   2221篇
  2014年   3261篇
  2013年   5228篇
  2012年   7423篇
  2011年   7674篇
  2010年   4272篇
  2009年   3998篇
  2008年   7256篇
  2007年   7935篇
  2006年   7600篇
  2005年   7668篇
  2004年   7529篇
  2003年   7102篇
  2002年   6942篇
  2001年   1658篇
  2000年   1457篇
  1999年   1495篇
  1998年   1582篇
  1997年   1395篇
  1996年   1242篇
  1995年   1227篇
  1994年   1078篇
  1993年   1001篇
  1992年   1195篇
  1991年   1124篇
  1990年   1034篇
  1989年   1052篇
  1988年   981篇
  1987年   1025篇
  1986年   952篇
  1985年   1011篇
  1984年   1091篇
  1983年   1089篇
  1982年   1205篇
  1981年   1113篇
  1980年   1060篇
  1979年   807篇
  1978年   723篇
  1977年   776篇
  1976年   712篇
  1975年   607篇
  1974年   578篇
  1973年   560篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
Background A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.Methods Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.Results Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1–3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16–0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (−16.3 vs −7.7 cm3, p = 0.033) with no significant difference between Mandard groups.Conclusion Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.Subject terms: Oesophageal cancer, Surgical oncology  相似文献   
14.
15.
16.

Objective

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

Methods

From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.

Results

Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).

Conclusions

Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes.  相似文献   
17.
18.
19.
20.
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