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   38365篇
  免费   3047篇
  国内免费   81篇
耳鼻咽喉   291篇
儿科学   1706篇
妇产科学   1184篇
基础医学   5191篇
口腔科学   401篇
临床医学   4654篇
内科学   7016篇
皮肤病学   684篇
神经病学   4529篇
特种医学   722篇
外科学   3715篇
综合类   354篇
现状与发展   1篇
一般理论   74篇
预防医学   5224篇
眼科学   596篇
药学   2505篇
中国医学   35篇
肿瘤学   2611篇
  2024年   81篇
  2023年   618篇
  2022年   990篇
  2021年   1951篇
  2020年   1156篇
  2019年   1674篇
  2018年   1881篇
  2017年   1271篇
  2016年   1438篇
  2015年   1494篇
  2014年   1960篇
  2013年   2460篇
  2012年   3568篇
  2011年   3448篇
  2010年   1727篇
  2009年   1484篇
  2008年   2277篇
  2007年   2365篇
  2006年   2000篇
  2005年   1834篇
  2004年   1568篇
  2003年   1296篇
  2002年   1166篇
  2001年   147篇
  2000年   107篇
  1999年   177篇
  1998年   230篇
  1997年   136篇
  1996年   114篇
  1995年   114篇
  1994年   106篇
  1993年   97篇
  1992年   54篇
  1991年   52篇
  1990年   44篇
  1989年   32篇
  1988年   24篇
  1987年   23篇
  1986年   28篇
  1985年   31篇
  1984年   30篇
  1983年   24篇
  1982年   25篇
  1981年   26篇
  1980年   30篇
  1979年   17篇
  1978年   15篇
  1977年   10篇
  1974年   8篇
  1972年   12篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.

Previous studies have shown that engagement strategies can help increase enrollment and initiation of families in evidence-based preventive programs under natural service delivery settings. However, little is known about factors that predict completion of these engagement strategies. This study aimed to examine predictors (i.e., perceived need, perceived barriers, and sociocultural context) of caregiver participation in an evidence-based engagement call strategy. This call was expected to increase initiation into a school-based, family-focused prevention program. In addition, this study examined engagement call completion as a predictor of program initiation among already enrolled families. Participants included ethnically diverse families recruited from three Title I schools (n = 413) who were randomized to receive the prevention program. Results showed that interparental conflict—an indicator of perceived need—was associated with an increased likelihood of completing the engagement call. Furthermore, caregivers from low-socioeconomic status (SES), foreign-born, Spanish-speaking, Hispanic families were more likely to complete the call relative to those from low- and mid-SES, US born, English-speaking, ethnically diverse families. Importantly, engagement call completion was associated with an increased likelihood of program initiation. These findings provide limited support that families with higher perceived needs are more likely to participate in an evidence-based engagement call strategy. Results suggested that the call strategy provides a promising way to reduce attrition from family prevention programs, which is commonly observed between enrollment and initiation. Project Number: R01 DA035855; Date of Registration: 06/15/2014.

  相似文献   
83.
84.
Journal of Occupational Rehabilitation - Purpose Little is currently known about how early intervention vocational rehabilitation (EIVR) works for people with newly acquired neurological conditions...  相似文献   
85.
86.
87.
BackgroundMost data on postoperative outcomes among patients with proximal extrahepatic cholangiocarcinoma are reported by single institutions. The purpose of this study was to analyze postoperative outcomes stratified by age and comorbidities.MethodsPatients with proximal extrahepatic cholangiocarcinoma who underwent a resection were identified in the National Cancer Database. Pathologic, postoperative, and survival outcomes were compared based on age and Charlson-Deyo comorbidity index.ResultsAmong the 1,579 patients, the average age was 66 years, and 9.4% of patients were older than 80 years. Most patients had a Charlson-Deyo score of 0 (72.4%), with the minority having scores of 1 (20.5%) or ≥2 (7.1%). Patients ≥80 years had a higher 90-day mortality rate compared with patients 65 to 79 and <65 years (21.3% vs 12.0% vs 7.4%, P < .001). Patients with a Charlson-Deyo score ≥2 had longer duration of stay, greater likelihood of requiring an unplanned readmission, and a higher 90-day mortality rate compared with patients with a lower comorbidity index. Median survival of patients <65, 65 to 79, and ≥80 years was 31, 24, and 17 months, respectively. A similar trend was seen with increasing Charlson-Deyo score (0: 27 months, 1: 25 months, ≥2: 20 months). On multivariable analysis, age ≥80 years (hazard ratio = 1.52, P = .01) and Charlson-Deyo score ≥2 (hazard ratio = 1.45, P = .01) were associated with poor survival.ConclusionIn patients with proximal extrahepatic cholangiocarcinoma, age ≥80 years and greater comorbidity index are associated with increased risk of 90-day mortality and poor overall survival. This suggests that resections in high-risk patient populations should be approached with caution.  相似文献   
88.
Annals of Surgical Oncology - Biomarker changes in patients with residual disease (RD) after neoadjuvant systemic therapy (NAT) have unclear consequences. This study examined the prevalence of...  相似文献   
89.
90.
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