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   15653篇
  免费   578篇
  国内免费   15篇
耳鼻咽喉   32篇
儿科学   449篇
妇产科学   518篇
基础医学   1114篇
口腔科学   190篇
临床医学   2244篇
内科学   2617篇
皮肤病学   94篇
神经病学   1101篇
特种医学   478篇
外科学   1986篇
综合类   131篇
现状与发展   1篇
预防医学   3571篇
眼科学   137篇
药学   734篇
中国医学   50篇
肿瘤学   799篇
  2024年   7篇
  2023年   1165篇
  2022年   1686篇
  2021年   1444篇
  2020年   1758篇
  2019年   891篇
  2018年   692篇
  2017年   768篇
  2016年   768篇
  2015年   733篇
  2014年   1250篇
  2013年   844篇
  2012年   542篇
  2011年   312篇
  2010年   686篇
  2009年   662篇
  2008年   209篇
  2007年   232篇
  2006年   196篇
  2005年   117篇
  2004年   78篇
  2003年   112篇
  2002年   118篇
  2001年   117篇
  2000年   74篇
  1999年   118篇
  1998年   129篇
  1997年   98篇
  1996年   104篇
  1995年   105篇
  1994年   68篇
  1993年   47篇
  1992年   23篇
  1991年   27篇
  1990年   31篇
  1989年   28篇
  1988年   2篇
  1986年   1篇
  1983年   2篇
  1976年   1篇
  1973年   1篇
排序方式: 共有10000条查询结果,搜索用时 328 毫秒
71.
72.
73.
Primary care physicians (PCPs) provide frontline health care to patients in the U.S.; however, it is unclear how their practice styles affect patient care. In this paper, we estimate the long-lasting effects of PCP practice styles on patient health care utilization by focusing on Medicare patients affected by PCP relocations or retirements, which we refer to as “exits.” Observing where patients receive care after these exits, we estimate event studies to compare patients who switch to PCPs with different practice style intensities. We find that PCPs have large effects on a range of aggregate utilization measures, including physician and outpatient spending and the number of diagnosed conditions. Moreover, we find that PCPs have large effects on the quality of care that patients receive, and that all of these effects persist for several years. Our results suggest that switching to higher-quality PCPs could significantly affect patients’ longer-run health outcomes.  相似文献   
74.
75.
《Journal of endodontics》2020,46(10):1371-1386.e8
IntroductionThis study aimed to summarize data on apical periodontitis (AP) and nonsurgical root canal treatment (NSRCT) prevalence and risk factors related to age, gender, and quality of restorative and endodontic treatment in the general population from cross-sectional studies published between 2012 and 2020.MethodsAn electronic search was performed in the following databases: Web of Science, Scopus, and PubMed. The conducted literature search covered studies published between 2012 and 2020, without restrictions on language. The STROBE and NOS tools were used for quality assessment of the included studies.ResultsSixteen articles were included in the review. In total, 200,041 teeth were examined. On average, 6.3% of teeth had AP, and 7.4% had NSRCT. Forty-one percent of RCT teeth had AP, and 3.5% of untreated teeth had AP. Female patients were less prone to AP in endodontically treated teeth only, compared with male patients (P < .001). Variable stratification of age subgroups among included studies prevented us from conducting a meta-analysis. An increase in AP frequency was found in teeth with inadequate restorative and endodontic treatment (P < .001 and P < .001, respectively). Because of high heterogeneity, these results should be taken with caution.ConclusionsThere is an increased AP prevalence in the adult general population compared with data from 2012 (6.3% versus 5.4%) in both endodontically treated (41.3% versus 35.9%) and untreated teeth (3.5% versus 2.1%). In addition, AP developed less frequently in female patients with endodontically treated teeth and in teeth with inadequate compared with adequate restorative and endodontic treatment.  相似文献   
76.
AimsTo explore the association between WWI and the incidence of HTN in the Rural Chinese Cohort Study.Methods and ResultsWe examined data for 10,338 non-hypertensive participants (39.49% men) aged ≥ 18 years from the Rural Chinese Cohort Study who completed a baseline examination during 2007–2008 and follow-up during 2013–2014. WWI was calculated as waist circumference (cm) divided by the square root of weight (kg). Multiple logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the probability of HTN across four WWI categories. Restricted cubic splines analysis was used to model the dose–response association of WWI and HTN. A total of 2078 participants had HTN during a median follow-up of 6 years. After adjusting for potential confounders, as compared with the lowest WWI category (<9.94 cm/√kg), with WWI 9.94 to 10.42, 10.42 to 10.91 and ≥ 10.91 cm/√kg, the ORs (95% CIs) for HTN were 1.12 (0.93–1.35), 1.40 (1.17–1.69) and 1.50 (1.24–1.82), respectively. Results of the sensitivity analyses were robust. The ORs were generally consistent on subgroup analysis by sex, smoking status, systolic blood pressure and diastolic blood pressure. Multiple logistic regression models with restricted cubic splines showed a non-linear positive association between WWI and HTN (Pnonlinearity < 0.001).ConclusionThe highest WWI category was significantly associated with increased risk of HTN. Our findings may facilitate the development and promotion of obesity prevention strategies aimed at reducing the risk of HTN and provide evidence for healthcare policy in rural China.  相似文献   
77.
78.
79.
80.
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