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   77367篇
  免费   5497篇
  国内免费   204篇
耳鼻咽喉   618篇
儿科学   2254篇
妇产科学   1303篇
基础医学   10578篇
口腔科学   1665篇
临床医学   8208篇
内科学   16399篇
皮肤病学   1049篇
神经病学   7403篇
特种医学   2557篇
外国民族医学   5篇
外科学   10611篇
综合类   948篇
一般理论   72篇
预防医学   6916篇
眼科学   1941篇
药学   5442篇
  1篇
中国医学   85篇
肿瘤学   5013篇
  2023年   359篇
  2022年   449篇
  2021年   1449篇
  2020年   880篇
  2019年   1425篇
  2018年   1728篇
  2017年   1287篇
  2016年   1424篇
  2015年   1656篇
  2014年   2491篇
  2013年   3379篇
  2012年   5511篇
  2011年   5667篇
  2010年   3151篇
  2009年   2815篇
  2008年   5120篇
  2007年   5604篇
  2006年   5462篇
  2005年   5230篇
  2004年   4982篇
  2003年   4544篇
  2002年   4405篇
  2001年   798篇
  2000年   603篇
  1999年   807篇
  1998年   961篇
  1997年   796篇
  1996年   685篇
  1995年   647篇
  1994年   556篇
  1993年   510篇
  1992年   479篇
  1991年   452篇
  1990年   410篇
  1989年   409篇
  1988年   395篇
  1987年   322篇
  1986年   345篇
  1985年   344篇
  1984年   405篇
  1983年   382篇
  1982年   423篇
  1981年   408篇
  1980年   383篇
  1979年   272篇
  1978年   310篇
  1977年   246篇
  1976年   178篇
  1974年   160篇
  1973年   151篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
2.
3.
4.
Journal of Neuro-Oncology - Adjuvant radiation is often used in patients with low grade gliomas with high-risk characteristics with a recommended dose of 45–54 Gy. We used the...  相似文献   
5.
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.

Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.

Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings.  相似文献   

6.
7.
The majority of hip fractures in the elderly are the result of a fall from standing or from a lower height. Current injury models focus mostly on femur strength while neglecting subject-specific loading. This article presents an injury modeling strategy for hip fractures related to sideways falls that takes subject-specific impact loading into account. Finite element models (FEMs) of the human body were used to predict the experienced load and the femoral strength in a single model. We validated these models for their predicted peak force, effective pelvic stiffness, and fracture status against matching ex vivo sideways fall impacts (n = 11) with a trochanter velocity of 3.1 m/s. Furthermore, they were compared to sideways impacts of volunteers with lower impact velocities that were previously conducted by other groups. Good agreement was found between the ex vivo experiments and the FEMs with respect to peak force (root mean square error [RMSE] = 10.7%, R2 = 0.85) and effective pelvic stiffness (R2 = 0.92, RMSE = 12.9%). The FEMs were predictive of the fracture status for 10 out of 11 specimens. Compared to the volunteer experiments from low height, the FEMs overestimated the peak force by 25% for low BMI subjects and 8% for high BMI subjects. The effective pelvic stiffness values that were derived from the FEMs were comparable to those derived from impacts with volunteers. The force attenuation from the impact surface to the femur ranged between 27% and 54% and was highly dependent on soft tissue thickness (R2 = 0.86). The energy balance in the FEMS showed that at the time of peak force 79% to 93% of the total energy is either kinetic or was transformed to soft tissue deformation. The presented FEMs allow for direct discrimination between fracture and nonfracture outcome for sideways falls and bridge the gap between impact testing with volunteers and impact conditions representative of real life falls. © 2019 American Society for Bone and Mineral Research.  相似文献   
8.
Animal and human studies suggest fish oil and green tea may have protective effect on prostate cancer. Fatty acid synthase (FAS) has been hypothesized to be linked to chemoprotective effects of both compounds. This study evaluated the independent and joint effects of fish oil (FO) and green tea supplement (epigallocatechin-3-gallate, EGCG) on FAS and Ki-67 levels in prostate tissue. Through a double-blinded, randomized controlled trial with 2 × 2 factorial design, 89 men scheduled for repeat prostate biopsy following an initial negative prostate biopsy were randomized into either FO alone (1.9 g DHA + EPA/day), EGCG alone (600 mg/day), a combination of FO and EGCG, or placebo. We used linear mixed-effects models to test the differences of prostate tissue FAS and Ki-67 by immunohistochemistry between pre- and post-intervention within each group, as well as between treatment groups. Results did not show significant difference among treatment groups in pre-to-post-intervention changes of FAS (P = 0.69) or Ki-67 (P = 0.26). Comparing placebo group with any of the treatment groups, we did not find significant difference in FAS or Ki-67 changes (all P > 0.05). Results indicate FO or EGCG supplementation for a short duration may not be sufficient to produce biologically meaningful changes in FAS or Ki-67 levels in prostate tissue.  相似文献   
9.
10.
The Yakima Valley Farm Workers Clinic (YVFWC) is one of the largest community health centers in the country with clinics throughout south-central Washington and northern Oregon. Its dental program consists of 14 dental clinics providing general and specialty services to the low-income populations it serves. Modeling itself after the YVFWC medical managed care program; the Dental program recently added value-based metrics to its dental practice after Oregon offered a value-based dental reimbursement plan in 2019. This is the first-step YVFWC's dental program that has taken to prepare for value-based reimbursement and transform its dental practice in order to reduce the disease burden in its patient population. The purpose of this article is to describe the processes YVFWC undertook to prepare itself for the new reimbursement model, which included the development of metrics, a metric validation process, a clinical dashboard, and a method for improving metrics. It also outlines its medical/dental integration improvement brought about by embedding hygienists into the medical primary care teams.  相似文献   
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