首页 | 官方网站   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   1330566篇
  免费   103348篇
  国内免费   5712篇
医药卫生   1439626篇
  2021年   10989篇
  2019年   10912篇
  2018年   15083篇
  2017年   11751篇
  2016年   12662篇
  2015年   14999篇
  2014年   20423篇
  2013年   29341篇
  2012年   40728篇
  2011年   42883篇
  2010年   26223篇
  2009年   24532篇
  2008年   39610篇
  2007年   42147篇
  2006年   42161篇
  2005年   40826篇
  2004年   39106篇
  2003年   37778篇
  2002年   36870篇
  2001年   64787篇
  2000年   67193篇
  1999年   57139篇
  1998年   15561篇
  1997年   14180篇
  1996年   14548篇
  1995年   13745篇
  1994年   13024篇
  1993年   11945篇
  1992年   44713篇
  1991年   43604篇
  1990年   42356篇
  1989年   40214篇
  1988年   36992篇
  1987年   36326篇
  1986年   33695篇
  1985年   32339篇
  1984年   24181篇
  1983年   20299篇
  1982年   11738篇
  1981年   10704篇
  1979年   21354篇
  1978年   14835篇
  1977年   12537篇
  1976年   11695篇
  1975年   12630篇
  1974年   14669篇
  1973年   14125篇
  1972年   12949篇
  1971年   11731篇
  1970年   11056篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Heart transplantation (HTx) is a useful therapy for end‐stage Chaga? cardiomyopathy; however, Chagas reactivation remains a mayor complication. Parasitological methods offer poor diagnostic sensitivity, and use of more sensitive tools such as the Polymerase chain reaction (PCR) is usually necessary. In the present study, reactivation incidence and PCR usefulness for early reactivation diagnosis, as well as for treatment response evaluation during follow‐up, were analyzed using Strout parasite detection test, in 10 of 222 consecutive HTx patients suffering Chagas cardiomyopathy. PCR strategies targeted to minicircle sequences (kDNA, detection limit 1 parasite/ 10 mL blood) and miniexon genes (SL‐DNA, 200 parasite/10 mL) were performed to compare parasite burdens between samples. No patients received prophylactic antiprotozoal therapy (benznidazole). Five patients (50%) exhibited clinical reactivation within a mean period of 71.6 days; positive Strout results were observed in most cases presenting clinical manifestations. kDNA‐PCR was positive 38–85 days before reactivation, whereas SLDNA‐PCR became positive only 7–21 days later, revealing post‐HTx parasitic load enhancement present prior to clinical reactivation development. Reactivations were successfully treated with benznidazole and generated negative PCR results. Results observed in this study indicate the value of PCR testing for an early diagnosis of Chagas reactivation as well as for monitoring treatment efficacy.  相似文献   
993.
994.
995.
996.
997.
998.
The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy.  相似文献   
999.
INTRODUCTION: An endovascular procedure for excluding an aorto-iliac aneurysm whilst simultaneously preserving one internal iliac artery is described in a patient with complex iliac pathology. REPORT: The procedure involved the use of Advanta V12 covered stents to bridge the gap between the contralateral limb of the main body of a custom-made Zenith stent graft and the internal iliac artery on the side of an external iliac artery occlusion. DISCUSSION: Minimal modifications to the standard design of modular stent grafts make it possible to treat high risk patient with complex pathology with minimal morbidity.  相似文献   
1000.
Inguinal hernia is a known complication after radical retropubic prostatectomy (RRP). We have investigated whether other types of lower midline incision surgery in males increase the risk of inguinal hernia. Male patients operated with open prostatectomy for benign prostate hyperplasia (n = 95), pelvic lymph node dissection for staging of prostate cancer (n = 88), or cystectomy for bladder cancer (n = 76) were identified and were sent questionnaires in which they were asked about postoperative inguinal hernia morbidity. Two-hundred and seventy-one men operated with RRP had previously received a similar questionnaire. The answers were compared with those from a control group of 953 men who had not undergone surgery. Annual attributional hernia morbidity and Kaplan–Meier hernia-free survival were calculated. The cumulative incidence of post-operative inguinal hernia and annual attributional hernia morbidity after the respective surgical procedures were clearly higher during the early years post-operation than for nonoperated patients. Inguinal hernia is a common postoperative complication in males after all the lower midline incision surgery investigated.  相似文献   
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-23

京公网安备 11010802026262号