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   1996029篇
  免费   151348篇
  国内免费   4303篇
耳鼻咽喉   29955篇
儿科学   59207篇
妇产科学   57709篇
基础医学   282062篇
口腔科学   60625篇
临床医学   172015篇
内科学   385216篇
皮肤病学   43196篇
神经病学   161129篇
特种医学   80053篇
外国民族医学   590篇
外科学   311904篇
综合类   50795篇
现状与发展   7篇
一般理论   674篇
预防医学   146030篇
眼科学   47927篇
药学   150253篇
  3篇
中国医学   4118篇
肿瘤学   108212篇
  2018年   17429篇
  2015年   17889篇
  2014年   25316篇
  2013年   38776篇
  2012年   51128篇
  2011年   53886篇
  2010年   31894篇
  2009年   30626篇
  2008年   51636篇
  2007年   56271篇
  2006年   56656篇
  2005年   55163篇
  2004年   54026篇
  2003年   52170篇
  2002年   50897篇
  2001年   88769篇
  2000年   91194篇
  1999年   77454篇
  1998年   21798篇
  1997年   19971篇
  1996年   19284篇
  1995年   18270篇
  1994年   17344篇
  1992年   62652篇
  1991年   60709篇
  1990年   59733篇
  1989年   58098篇
  1988年   54363篇
  1987年   53567篇
  1986年   51244篇
  1985年   49012篇
  1984年   37340篇
  1983年   31759篇
  1982年   19528篇
  1981年   17984篇
  1980年   16734篇
  1979年   36775篇
  1978年   26372篇
  1977年   22708篇
  1976年   20632篇
  1975年   22990篇
  1974年   27876篇
  1973年   26966篇
  1972年   25773篇
  1971年   24063篇
  1970年   22901篇
  1969年   22017篇
  1968年   20300篇
  1967年   18505篇
  1966年   17277篇
排序方式: 共有10000条查询结果,搜索用时 609 毫秒
31.
32.

Background and objectives

A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.

Case report

A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.

Conclusion

Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma.  相似文献   
33.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
34.
35.
36.
37.
We report on a child with several café au lait spots in association with a lumbar lipomeningomyelocele as an apparently new association. Cutaneous markers, the identification of which plays a crucial role in the early diagnosis and management of spinal malformations, can accompany occult spinal dysraphism. Herein we report a case of lumbar lipomeningomyelocele associated with an overlying café au lait spot that served as a marker of occult spinal dysraphism. The patient also had segmental café au lait spots on the face, making the association unique.  相似文献   
38.
39.
40.
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