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   53518篇
  免费   4125篇
  国内免费   1320篇
耳鼻咽喉   1189篇
儿科学   1048篇
妇产科学   374篇
基础医学   5670篇
口腔科学   3654篇
临床医学   3617篇
内科学   4247篇
皮肤病学   280篇
神经病学   1209篇
特种医学   4072篇
外国民族医学   4篇
外科学   20856篇
综合类   5949篇
现状与发展   2篇
一般理论   1篇
预防医学   1401篇
眼科学   568篇
药学   1767篇
  28篇
中国医学   783篇
肿瘤学   2244篇
  2024年   42篇
  2023年   717篇
  2022年   1103篇
  2021年   1676篇
  2020年   1760篇
  2019年   1678篇
  2018年   1850篇
  2017年   1663篇
  2016年   1821篇
  2015年   1875篇
  2014年   3294篇
  2013年   3484篇
  2012年   2786篇
  2011年   3280篇
  2010年   2615篇
  2009年   2828篇
  2008年   2835篇
  2007年   2819篇
  2006年   2672篇
  2005年   2556篇
  2004年   2140篇
  2003年   1781篇
  2002年   1345篇
  2001年   1224篇
  2000年   1140篇
  1999年   965篇
  1998年   817篇
  1997年   770篇
  1996年   611篇
  1995年   599篇
  1994年   536篇
  1993年   418篇
  1992年   392篇
  1991年   317篇
  1990年   279篇
  1989年   247篇
  1988年   236篇
  1987年   186篇
  1986年   203篇
  1985年   189篇
  1984年   160篇
  1983年   88篇
  1982年   148篇
  1981年   126篇
  1980年   120篇
  1979年   122篇
  1978年   94篇
  1977年   81篇
  1976年   66篇
  1973年   41篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.

Purpose

To compare the efficacy and safety of recombinant human bone morphogenetic protein (rhBMP) and iliac crest autograft in the fusion treatment of lumbar spondylolisthesis.

Methods

The studies using randomized controlled trials to compare the rhBMP with iliac crest autograft in the treatment of lumbar spondylolisthesis were retrieved from Embase, Pubmed, ProQuest dissertations & theses (PQDT), China national knowledge infrastructure (CNKI), Chinese Biomedical Database, Wanfang Data, Cochrane Library (from March 1998 to March 2018). Postoperative fusion rate, clinical success rate, postoperative intervertebral height, complications, operation time, blood loss and duration of hospitalization were chosen as the outcome indicators. Methodological quality of the trials was critically assessed, and relevant data were extracted. Statistical software Revman 5.3 was used for data-analysis.

Results

Eleven articles were included in the meta-analysis. The results showed that, comparing the efficacy of rhBMP with iliac crest autograft, statistical significance was found in the 24-month fusion rate post operation [95% CI (1.38, 24.70), p = 0.02] and operation time [95% CI (?14.22, ?2.08), p = 0.008]. There is not sufficient evidence for statistical differences in the remaining indicators.

Conclusion

The current literature shows rhBMP is a safe and effective grafting material in the treatment of lumbar spondylolisthesis. Further evidence is dependent on the emergence of more randomized controlled trials with higher quality and larger sample sizes in the future.  相似文献   
42.
目的探讨髋臼螺钉在非骨水泥全髋置换术中对髋臼假体稳定性的影响。 方法回顾性分析2009年8月至2015年8月在深圳市龙岗区人民医院骨科行非骨水泥全髋置换术114例(117髋)病例资料,患者根据术中是否植入髋臼螺钉分成两组,其中A组无螺钉组59髋,B组螺钉固定组58髋。分别在术后3个月、12个月、24个月和末次随访时对病人进行随访,评估并比较影像学的改变及Harris评分。A组57髋B组56髋获得完整随访资料,平均随访(5.7±1.6)年。以Kaplan-Meier法分析两组假体生存率。 结果A组平均手术时间(t=2.213, P<0.05)、术中出血量均小于B组(t=2.342, P<0.05);随访末期,A、B组术后平均Harris评分为(95.0±2.1)分及(93.0±5.5)分(P>0.05);A、B组术后3个月、12个月、24个月分别有4髋(7.0%)、3髋(5.3%)、1髋(1.8%)和1髋(1.8%)、2髋(3.6%)及2髋(3.6%)出现髋臼周围透亮线;A组1髋术后4年出现骨溶解,B组2髋出现骨溶解。以影像学证明假体松动作为失败标准,计算两组假体平均随访(5.7±1.6)年生存率分别为97%和95%,两者差异无统计学意义(P >0.05)。 结论髋臼骨质条件良好时是否使用髋臼螺钉固定对臼杯的稳定性无明显影响,全髋关节置换术中植入髋臼螺钉不是必需的。  相似文献   
43.
重点概述2018年美国移植大会及第27届国际移植大会有关器官移植基础、临床及转化医学研究的前沿热点及最新进展,包括供者特异性抗体、抗体介导排斥反应、临床免疫耐受、供器官合理利用、供肝保存新技术应用及移植相关病毒感染等概要内容。  相似文献   
44.
45.

Introduction

The aim of this study was to determine whether complications following mastectomy with immediate breast reconstruction (IBR) were associated with breast cancer recurrence.

Methods

A retrospective review was performed of women diagnosed with stage I-III breast cancer who underwent mastectomy with IBR between 2005 and 2010. Patient demographics, tumor data, surgical wound complications, treatment details and timing were recorded and analyzed.

Results

We identified 458 women with a median follow up time of 7.6 years. A total of 22% of patients experienced IBR complications. There was a delay in initiation of adjuvant therapy in patients who had a complication (52 vs 41 days, p?<?0.001). There was no significant difference in recurrences between groups with and without complications (p?=?0.65).

Conclusions

In breast cancer patients who undergo mastectomy with IBR, wound complications delayed initiation of adjuvant systemic therapy, but were not associated with an increased risk of cancer recurrence.  相似文献   
46.
正胆道缝合重建是肝胆胰外科手术的最基本操作之一,建立胆汁引流通畅、无张力、血供充足的黏膜对黏膜吻合是胆道重建的基本要求。目前,胆道重建方式繁多,但根据所须重建胆道的病理生理状况选择合适的胆道缝合方法及缝合材料是保障胆道重建成功的关键因素。随着手术技术的进步及各种缝合材料的发展,胆道缝合技术越来越精细,高质量的胆道缝合重建是病人顺利康复及减少多次手术的关键。基于此,中华医学会外科学分会组织国内部分专家结合最新文献及胆道外科的最新进  相似文献   
47.
48.
49.
Objective: Quadriceps dysfunction has been suggested as a complication after medial patellofemoral ligament (MPFL) reconstruction. The purpose of this study was to investigate changes in knee extensor strength before and after MPFL reconstruction.

Methods: Twenty patients who underwent MPFL reconstruction for unilateral recurrent patellar dislocation (18 females and 2 males; mean age 20.8 ± 7.6 years) were examined. The peak isometric torque at 60° and 90° of knee flexion and isokinetic knee extensor strength at speeds of 60°/s and 90°/s in operated and non-operated legs were measured using a dynamometer preoperatively and 6 months, 1 year, and 2 years postoperatively. The following parameters were evaluated: (1) body weight-adjusted muscle strength, (2) improvement index (post-/preoperative value × 100) (%), and (3) extensor strength ratio (operated/non-operated value × 100) (%).

Results: The mean knee extensor strength in both operated and non-operated legs significantly increased 2 years after surgery compared with that before surgery. At 2 years postoperatively, the improvement indexes of the isometric knee extensor strength at 60° and 90° and of the isokinetic knee extensor strength at 60°/s and 90°/s were 237%, 192%, 318%, and 186%, respectively, in the operated legs and 144%, 124%, 140%, and 140%, respectively, in the non-operated legs. At 2 years postoperatively, the mean isometric knee extensor strength ratios at 60° and 90° and the isokinetic knee extensor strength ratios at 60°/s and 180°/s were 81%, 84%, 81%, and 82%, respectively.

Conclusions: Knee extensor strength was improved in most patients after MPFL reconstruction, at least compared with that before surgery, although an approximately 20% deficit against the non-operated legs remained even 2 years after surgery.  相似文献   

50.
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