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   62447篇
  免费   4632篇
  国内免费   147篇
耳鼻咽喉   821篇
儿科学   1723篇
妇产科学   1594篇
基础医学   10256篇
口腔科学   1677篇
临床医学   5875篇
内科学   12444篇
皮肤病学   962篇
神经病学   5883篇
特种医学   2627篇
外国民族医学   45篇
外科学   8139篇
综合类   527篇
一般理论   83篇
预防医学   4870篇
眼科学   1195篇
药学   4558篇
中国医学   162篇
肿瘤学   3785篇
  2021年   905篇
  2020年   649篇
  2019年   918篇
  2018年   1122篇
  2017年   780篇
  2016年   918篇
  2015年   1085篇
  2014年   1336篇
  2013年   2321篇
  2012年   2989篇
  2011年   3082篇
  2010年   2224篇
  2009年   1863篇
  2008年   2789篇
  2007年   2931篇
  2006年   2916篇
  2005年   2760篇
  2004年   2821篇
  2003年   2556篇
  2002年   2617篇
  2001年   2131篇
  2000年   2169篇
  1999年   1919篇
  1998年   763篇
  1997年   639篇
  1996年   551篇
  1995年   651篇
  1994年   546篇
  1993年   597篇
  1992年   1439篇
  1991年   1392篇
  1990年   1331篇
  1989年   1315篇
  1988年   1097篇
  1987年   1100篇
  1986年   1042篇
  1985年   959篇
  1984年   689篇
  1983年   645篇
  1982年   454篇
  1981年   440篇
  1980年   375篇
  1979年   622篇
  1978年   373篇
  1977年   357篇
  1975年   371篇
  1974年   413篇
  1973年   347篇
  1972年   339篇
  1971年   302篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
12.
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  相似文献   
13.
World Journal of Surgery - Routine preoperative staging in pancreas cancer is controversial. We sought to evaluate the rates of diagnostic laparoscopy (DLAP) for pancreatic cancer. We queried the...  相似文献   
14.
Genetic and epigenetic alterations importantly contribute to the pathogenesis of lung cancer. In the study, we measured the frequency and distribution of molecular abnormalities of EGFR as well as the aberrant promoter methylations of BRCA1, MGMT, MLH1, and RASSF1A in Vietnamese lung adenocarcinomas. We investigated the association between genetic and epigenetic alteration, and between each abnormality with clinicopathologic parameters. Somatic EGFR mutation that was found in 49/139 (35.3%) lung adenocarcinomas showed a significant association with young age, female gender, and non-smokers. EGFR overexpression was identified in 82 tumors (59.0%) and statistical relationships with EGFR or BRCA1 methylation but not EGFR mutation. In addition, EGFR, BRCA1, MGMT, MLH1, and RASSF1A methylations were found in 33 (23.7%), 41 (29.5%), 46 (33.1%), 28 (20.1%), and 41 (29.5%) cases of a total of 139 lung adenocarcinomas, respectively. The RASSF1A methylation was found to be linked to the smoking habit. Methylations in MGMT and RASSF1A were also found to correlate with metastasis status. Furthermore, the distribution of EGFR mutation and that of BRCA1, MGMT or RASSF1A methylation were significantly exclusive in lung adenocarcinomas. The main finding of our study demonstrate that epigenetic abnormalities might play a critical role for the lung tumorigenesis in patients with smoking history and metastasis, and partly affect the predictive value of EGFR mutations through blocking expression due to promoter EGFR hypermethylation. Mutually exclusive distribution of genetic and epigenetic alterations reflects differently biological characteristics in the etiology of lung adenocarcinomas.  相似文献   
15.
Objectives: Evidence-based depression therapies are difficult to implement in nursing homes. We present data for BE-ACTIV, a 10-week depression treatment designed for implementation in nursing homes, to address questions of treatment fidelity (delivery, receipt, and enactment) in that context.

Method: Participants were 41 patients from 13 nursing homes in the treatment arm of a clinical trial, treated by graduate student therapists. Therapists and their supervisor rated their audio-recorded sessions for adherence to treatment protocol and session quality.

Results: Delivery of core program elements averaged from 80–94% across all sessions; mean quality was 5.6 (SD 0.61) out of 6 points. Delivery of core components to nursing home activities staff who collaborated in the treatment was similarly high. Patients received an average of 7.32 sessions (SD 3.39); 17 completed 10 sessions. The theoretical basis of BE-ACTIV is behavioral activation; therapist-client dyads planned new pleasant events weekly, from a mean of 3.66 (SD 1.35) after the first session to a mean of between 5 and 6 activities a week across sessions 6–9, with a similar progression in percent activities completed. Activities enactment was significantly related to the likelihood of remission at post-treatment, and of maintaining improvement at 3-month follow-up. Treatment receipt and enactment were also related to improved mood from baseline to 3 months.

Conclusion: Results demonstrate delivery, receipt, and successful enactment of BE-ACTIV core components in diverse nursing homes and patients, and support the theoretical premise of the intervention. These findings support further implementation work for the BE-ACTIV intervention.  相似文献   

16.
17.
18.
The Lapidus bunionectomy is performed to treat hallux valgus. Recurrence of the deformity remains a concern. A transverse intermetatarsal screw spanning the base of the first metatarsal to the base of the second can increase stability. The neurovascular bundle is located within the proximity of this screw. In this study, we assessed the structures at risks with the use of this technique. In 10 specimens, a guide wire was placed, and a 4.0-mm cannulated screw was inserted. The neurovascular bundle was dissected and inspected for direct trauma to the neurovascular bundle, and the proximity of the screw was measured using a digital caliper. Ten cadaveric specimens were used. The dorsalis pedis artery and deep peroneal nerve were free from injury in 9 of 10 specimens. In those 9 specimens, the neurovascular bundle was located dorsal in relation to the screw. The mean distance of the screw to the neurovascular bundle was 7.1 ± 3.3 mm. The mean distance from the screw to the first tarsometatarsal joint (TMTJ) was 14.7 ± 4.3 mm. The mean distance from the screw as it entered the second metatarsal to the second TMTJ was 18.0 ± 7.2 mm. In 1 specimen, the screw was found to be traversing through the neurovascular bundle. The distance from the screw to the first TMTJ was 15.0 mm. The distance of the screw from where it entered the second metatarsal to the second TMTJ was 24.0 mm. Although the intermetatarsal screw avoided the neurovascular cases in most instances, there is some anatomic risk to the neurovascular bundle. Further study is warranted to evaluate clinical results using the intermetatarsal screw for the modified Lapidus procedure.  相似文献   
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