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   1254646篇
  免费   79678篇
  国内免费   7908篇
耳鼻咽喉   15528篇
儿科学   33446篇
妇产科学   29462篇
基础医学   167087篇
口腔科学   32592篇
临床医学   109832篇
内科学   237845篇
皮肤病学   21606篇
神经病学   96573篇
特种医学   50462篇
外国民族医学   119篇
外科学   198761篇
综合类   40078篇
现状与发展   21篇
一般理论   260篇
预防医学   90533篇
眼科学   27607篇
药学   96452篇
  118篇
中国医学   9245篇
肿瘤学   84605篇
  2021年   11085篇
  2019年   9656篇
  2018年   35678篇
  2017年   28943篇
  2016年   32397篇
  2015年   15113篇
  2014年   19631篇
  2013年   25401篇
  2012年   41434篇
  2011年   57827篇
  2010年   41520篇
  2009年   32782篇
  2008年   54054篇
  2007年   58524篇
  2006年   34778篇
  2005年   35342篇
  2004年   34192篇
  2003年   34421篇
  2002年   30948篇
  2001年   57813篇
  2000年   59631篇
  1999年   49528篇
  1998年   12381篇
  1997年   11106篇
  1996年   10805篇
  1995年   10102篇
  1994年   9398篇
  1993年   8277篇
  1992年   36381篇
  1991年   34762篇
  1990年   33466篇
  1989年   32488篇
  1988年   29551篇
  1987年   28740篇
  1986年   26719篇
  1985年   25509篇
  1984年   18105篇
  1983年   15399篇
  1982年   8040篇
  1979年   16012篇
  1978年   10779篇
  1977年   9160篇
  1976年   8030篇
  1975年   8688篇
  1974年   10603篇
  1973年   9954篇
  1972年   9425篇
  1971年   8894篇
  1970年   8497篇
  1969年   8008篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
2.
3.
BackgroundComminuted patellar fractures are not rare, and the ideal treatment method remains controversial. The present study was conducted to evaluate effects and compare complications of two different methods used to treat comminuted patellar fractures.MethodsFrom March 2010 to August 2016, 102 cases of 34-C2 or 34-C3 comminuted patellar fractures were treated at our hospital, wherein patients received two different treatments: titanium cable tension band with cerclage method (group A) and intrafragmentary screws with X-shaped plating technique (group B). At follow-ups, articular step-off, range of motion (ROM), Lysholm scores, time of union, and complications were recorded and analyzed. Radiographic and clinical data as well as rate of complications were statistically analyzed.ResultsIn total, 87 patients were included in the final analysis (n = 47 in group A and n = 40 in group B). No significant differences were noted in terms of cost of implant, age, gender, rate of 34-C3 fractures, rate of layered inferior pole fractures, postoperative articular step-off and union time. At 2-year follow-up, average Lysholm scores, ROM and rate of complications were (89.0 ± 4.5), (122°±12°) and (27.7%) in group A and (90.2 ± 3.9), (124°±11°) and (17.5%) in group B, respectively, with no significant differences (p > 0.05). The mean time of surgery in group B was shorter than that in group A with significant difference (p < 0.05).ConclusionsTreatment using the intrafragmentary screws and plate method for amenable comminuted patellar fractures achieved similar complication rate and favorable functional outcomes at the 2-year follow-up, which was comparable to the titanium cable tension band with cerclage method. Thus, the intrafragmentary screws and plate method is effective, safe and convenient for 34-C2/C3 comminuted patellar fractures, especially appropriate for patients with layered fragments.  相似文献   
4.
5.
6.
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was...  相似文献   
7.

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.

Methods

Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.

Results

A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.

Conclusions

Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight.  相似文献   
8.
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