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   23575篇
  免费   1490篇
  国内免费   95篇
耳鼻咽喉   320篇
儿科学   669篇
妇产科学   491篇
基础医学   3439篇
口腔科学   1594篇
临床医学   2547篇
内科学   4494篇
皮肤病学   550篇
神经病学   2087篇
特种医学   438篇
外科学   2174篇
综合类   160篇
一般理论   13篇
预防医学   2731篇
眼科学   420篇
药学   1621篇
中国医学   154篇
肿瘤学   1258篇
  2023年   240篇
  2022年   199篇
  2021年   850篇
  2020年   574篇
  2019年   838篇
  2018年   946篇
  2017年   669篇
  2016年   690篇
  2015年   814篇
  2014年   1057篇
  2013年   1293篇
  2012年   2038篇
  2011年   2197篇
  2010年   1077篇
  2009年   945篇
  2008年   1610篇
  2007年   1532篇
  2006年   1387篇
  2005年   1243篇
  2004年   1042篇
  2003年   969篇
  2002年   922篇
  2001年   224篇
  2000年   193篇
  1999年   186篇
  1998年   139篇
  1997年   94篇
  1996年   76篇
  1995年   80篇
  1994年   70篇
  1993年   68篇
  1992年   72篇
  1991年   82篇
  1990年   64篇
  1989年   44篇
  1988年   52篇
  1987年   44篇
  1986年   41篇
  1985年   39篇
  1984年   44篇
  1983年   36篇
  1982年   34篇
  1981年   25篇
  1980年   39篇
  1979年   33篇
  1977年   19篇
  1975年   18篇
  1974年   22篇
  1973年   18篇
  1970年   18篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Prostate-specific antigen (PSA)-based screening for prostate cancer (PCa) can reduce PCa mortality, but also involves overdetection of low-risk disease with potential adverse effects. We evaluated PCa incidence among men with PSA below 3 ng/mL and no PCa diagnosis at the first screening round of the Finnish Randomized Study of Screening for PCa. Follow-up started at the first screening attendance and ended at PCa diagnosis, emigration, death or the common closing date (December 2016), whichever came first. Cox regression analysis was used to estimate hazard ratios and their confidence intervals (CI). Among men with PSA <3 ng/mL, cumulative PCa incidence was 9.1% after 17.6 years median follow-up. Cumulative incidence was 3.6% among men with baseline PSA 0 to 0.99 ng/mL, 11.5% in those with PSA 1.0 to 1.99 ng/mL and 25.7% among men with PSA 2 to 2.99 ng/mL (hazard ratio 9.0, 95% CI: 7.9-10.2 for the latter). The differences by PSA level were most striking for low-risk disease based on Gleason score and EAU risk group. PSA values <1 ng/mL indicate a very low 20-year risk, while at PSA 2 to 2.99 ng/mL risks are materially higher, with 4- to 5-fold risk for aggressive disease. Using risk-stratification and appropriate rescreening intervals will reduce screening intensity and overdetection. Using cumulative incidence of clinically significant PCa (csPCa) as the criterion, rescreening intervals could range from approximately 3 years for men with initial PSA 2 to 2.99 ng/mL, 6 years for men with PSA 1 to 1.99 ng/mL to 10 years for men with PSA <1 ng/mL.  相似文献   
3.
Clinical Oral Investigations - To evaluate and to compare the clinical performance and survival rate of posterior monolithic and veneered zirconia fixed partial dentures (FPDs). Sixty 3-unit...  相似文献   
4.
5.
6.
Rosmarinus species are aromatic plants that mainly grow in the Mediterranean region. They are widely used in folk medicine, food, and flavor industries and represent a valuable source of biologically active compounds (e.g., terpenoids, flavonoids, and phenolic acids). The extraction of rosemary essential oil is being done using three main methods: carbon dioxide supercritical extraction, steam distillation, and hydrodistillation. Furthermore, interesting antioxidant, antibacterial, antifungal, antileishmanial, anthelmintic, anticancer, anti‐inflammatory, antidepressant, and antiamnesic effects have also been broadly recognized for rosemary plant extracts. Thus the present review summarized data on economically important Rosmarinus officinalis species, including isolation, extraction techniques, chemical composition, pharmaceutical, and food applications.  相似文献   
7.
A disease-focused course entitled “Understanding Sickle Cell Disease: A Biopsychosocial Approach” addressed the complex nature of SCD using patient-centered, global and interdisciplinary approaches. Sickle cell disease (SCD) is a rare inherited blood disorder that requires multidisciplinary care. Worldwide 20–25 million individuals have SCD, which is associated with a shortened lifespan due to many medical complications and social and behavioral health challenges. Health care professionals often have limited knowledge of SCD as they typically learn about it within the context of their own disciplines. This article provides twelve tips for educators that can be used to develop a similar course on any disease, with considerations for both low- and high-resource countries. The tips were devised from personal experience and available literature. Through these twelve tips, we provide a practical framework for increasing knowledge of complex diseases like SCD using a comprehensive elective course.  相似文献   
8.
Bulletin of Environmental Contamination and Toxicology - This work describes the development of an analytical protocol combining cleanup by liquid–solid extraction and GC–MS for the...  相似文献   
9.
The presence of dental abnormalities in the same individual may be related to syndromic cases and occur through associated systemic changes. Kabuki syndrome presents well‐defined systemic changes, but its clinical characteristics related to the oral cavity have not been fully explained. This study aimed to report the dental changes in a child diagnosed with Kabuki syndrome. A male brown patient aged 2 years and 7 months, accompanied by his mother to the dental visit, they main complaint was the presented of an additional tooth behind upper right central incisor. Anamnesis, intra‐ and extraoral examinations, and dental X‐rays were performed, revealing a talon cusp. Considering the dental clinical findings, the patient was referred to a medical geneticist who additionally requested cardiological and genetic examinations, which established the Kabuki syndrome. The caregivers were advised that the talon cusp would not cause any injury to the natural exfoliation of the tooth and that oral hygiene should be performed carefully. Abnormalities in the oral cavity and developmental delay may be associated with a potential undiagnosed syndrome. The medical evaluation becomes decisive for investigation, diagnosis, and final conduct of the case.  相似文献   
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