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   7495篇
  免费   544篇
  国内免费   219篇
耳鼻咽喉   33篇
儿科学   47篇
妇产科学   158篇
基础医学   809篇
口腔科学   83篇
临床医学   690篇
内科学   1107篇
皮肤病学   49篇
神经病学   456篇
特种医学   338篇
外国民族医学   3篇
外科学   767篇
综合类   1385篇
现状与发展   27篇
预防医学   835篇
眼科学   37篇
药学   549篇
  2篇
中国医学   230篇
肿瘤学   653篇
  2024年   9篇
  2023年   468篇
  2022年   496篇
  2021年   677篇
  2020年   719篇
  2019年   320篇
  2018年   263篇
  2017年   317篇
  2016年   271篇
  2015年   346篇
  2014年   561篇
  2013年   420篇
  2012年   424篇
  2011年   374篇
  2010年   385篇
  2009年   367篇
  2008年   251篇
  2007年   342篇
  2006年   281篇
  2005年   205篇
  2004年   218篇
  2003年   156篇
  2002年   128篇
  2001年   102篇
  2000年   24篇
  1999年   31篇
  1998年   34篇
  1997年   25篇
  1996年   28篇
  1995年   1篇
  1993年   2篇
  1992年   4篇
  1991年   1篇
  1990年   6篇
  1985年   2篇
排序方式: 共有8258条查询结果,搜索用时 375 毫秒
1.
  1. Download : Download high-res image (173KB)
  2. Download : Download full-size image
  相似文献   
2.
3.
BackgroundThe American Joint Committee on Cancer (AJCC) made improvements for staging pancreatic neuroendocrine tumors (pNETs) in its 8th Edition; however, multicenter studies were not included.MethodsWe collected multicenter datasets (n = 1,086, between 2004 and 2018) to validate the value of AJCC 8 and other coexisting staging systems through univariate and multivariate analysis for well-differentiated (G1/G2) pNETs.ResultsCompared to other coexisting staging systems, AJCC 7 only included 12 (1.1%) patients with stage III tumors. Patients with European Neuroendocrine Tumor Society (ENETS) stage IIB disease had a higher risk of death than patients with stage IIIA (hazard ratio [HR]: 4.376 vs. 4.322). For the modified ENETS staging system, patients with stage IIB disease had a higher risk of death than patients with stage III (HR: 6.078 vs. 5.341). According to AJCC 8, the proportions of patients with stage I, II, III, and IV were 25.7%, 40.3%, 23.6%, and 10.4%, respectively. As the stage advanced, the median survival time decreased (NA, 144.7, 100.8, 72.0 months, respectively), and the risk of death increased (HR: II = 3.145, III = 5.925, and IV = 8.762).ConclusionThese findings suggest that AJCC 8 had a more reasonable proportional distribution and the risk of death was better correlated with disease stage.  相似文献   
4.
5.
6.
《Injury》2022,53(12):3962-3969
IntroductionEducators are exposed to several work-related hazards. Evidence suggests musculoskeletal pain, psychological distress, and student-inflicted violence-related injuries are common. However, there is little evidence on the burden of workplace injury among Australian educators.AimTo compare incidence of injury claims and duration of compensated time off work between educators and non-educators, and associated factors.MethodsRetrospective cohort study of 1,559,676 Australian workers’ compensation claims, including 84,915 educator claims, lodged between July 2009 to June 2015, from the National Dataset for Compensation-based Statistics. Cases were included if aged 18+ years and working in the education sector less than 100 h per week. Negative binomial regression models estimated the relative risk of making a compensation claim and survival analyses calculated disability duration within educators by sex, age, injury type and mechanism, socioeconomic area, remoteness, and jurisdiction.ResultsCompared to non-educators, educators had lower rates of injury claims and shorter disability durations. However, educators had a higher rate of claims for mental health conditions and assault, with the highest risk being among those in special education and education aides. Among educators, injury claim rates were highest among special educators, education aides, and secondary educators.Discussion and ConclusionThough surveys indicate Australians in the education sector have higher incidences of work-related injuries, this study found lower incidence of injury claims and shorter disability durations than others. Educators’ injury-reporting and absenteeism behaviors may be constrained by ethical, social, and administrative attitudes. Educators had higher rates of claims for mental health and assault-related injury, particularly special educators, and education aides, which suggests a need for targeted prevention efforts.  相似文献   
7.
8.
IntroductionDifferent muscular activities of the quadriceps components for producing necessary torque may change in patients with patellofemoral pain syndrome (PFPS). The aim of the current study, therefore, was to assess the contribution of each component of the quadriceps femoris muscle for producing external torque in patients with PFPS.MethodTwelve females with PFPS (24.7 ± 2.3 years) and twelve healthy matched females (25.4 ± 2.4 years) performed three consecutive knee flexion and extension movements with maximum effort at 45°/s and 300°/s using a Biodex system 3 dynamometer. Simultaneously, electromyographic (EMG) activities of the vastus medialis oblique (VMO), RF (rectus femoris) and vastus lateralis (VL) muscles were recorded using a DataLog instrument. Standard multiple regressions were used to assess the ability of EMG activities of the VMO, RF and VL muscles to predict normalized quadriceps femoris isokinetic concentric and eccentric torques at 45°/s and 300°/s in the normal and patient groups.ResultsIn the normal group, the VL and the VMO were the good predictors of quadriceps concentric torque at 45°/s and 300°/s, respectively. The VL and the RF were the good predictors of quadriceps eccentric torque at 300°/s in the patient group. No other conditions showed a considerable prediction for quadriceps torque in the normal or patient group.ConclusionFemales with PFPS differ with normal females in terms of the contribution of each component of the quadriceps femoris for producing external torque. Training the VMO for concentric contraction at both high and low velocities should be included in the management of the patients with PFPS.  相似文献   
9.
10.
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