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   2581篇
  免费   178篇
  国内免费   22篇
耳鼻咽喉   17篇
儿科学   66篇
妇产科学   61篇
基础医学   453篇
口腔科学   65篇
临床医学   153篇
内科学   532篇
皮肤病学   36篇
神经病学   178篇
特种医学   79篇
外科学   399篇
综合类   134篇
一般理论   1篇
预防医学   160篇
眼科学   44篇
药学   197篇
中国医学   23篇
肿瘤学   183篇
  2023年   25篇
  2022年   52篇
  2021年   75篇
  2020年   39篇
  2019年   69篇
  2018年   58篇
  2017年   52篇
  2016年   75篇
  2015年   102篇
  2014年   175篇
  2013年   162篇
  2012年   210篇
  2011年   228篇
  2010年   136篇
  2009年   115篇
  2008年   144篇
  2007年   142篇
  2006年   138篇
  2005年   103篇
  2004年   94篇
  2003年   96篇
  2002年   70篇
  2001年   53篇
  2000年   38篇
  1999年   52篇
  1998年   18篇
  1997年   15篇
  1996年   17篇
  1995年   13篇
  1994年   14篇
  1993年   5篇
  1992年   25篇
  1991年   22篇
  1990年   13篇
  1989年   17篇
  1988年   13篇
  1987年   12篇
  1986年   12篇
  1985年   12篇
  1984年   11篇
  1982年   5篇
  1981年   4篇
  1975年   5篇
  1973年   4篇
  1971年   3篇
  1970年   3篇
  1969年   3篇
  1968年   5篇
  1966年   4篇
  1965年   3篇
排序方式: 共有2781条查询结果,搜索用时 296 毫秒
51.
52.
Anal endosonography is a new technique that is useful in the preoperative assessment of patients with anal fistulas. Endosonographic images are created by the reflection of sound waves from the interfaces between tissues of varying densities. In order to accentuate tissue interface layers at the level of the fistula tract, we introduced hydrogen peroxide into the fistula tract through the external opening during anal ultrasonography in two patients with recurrent anal fistula. Hydrogen peroxide injection resulted in hyperechoic imaging of the preinjection hypoechoic horseshoe fistula tract. Endosonographic findings were confirmed at the time of surgery in both patients. We conclude that hydrogen peroxide enhancement of the fistula tract is a simple, effective, and safe method of improving the accuracy of endoanal ultrasound assessment of recurrent anal fistula.Dr. Cheong is a visiting clinician from the Department of Surgery, Tan Tock Seng Hospital, Moulmein Road, Singapore 1130.  相似文献   
53.
54.
BackgroundThis study presents a framework for determining the allocation and distribution of the limited amount of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).MethodsAfter analyzing the pandemic strategies of the major organizations and countries and with a literature review conducted by a core panel, a modified Delphi survey was administered to 13 experts in the fields of vaccination, infectious disease, and public health in the Republic of Korea. The following topics were discussed: 1) identifying the objectives of the vaccination strategy, 2) identifying allocation criteria, and 3) establishing a step-by-step vaccination framework and prioritization strategy based on the allocation criteria. Two rounds of surveys were conducted for each topic, with a structured questionnaire provided via e-mail in the first round. After analyzing the responses, a meeting with the experts was held to obtain consensus on how to prioritize the population groups.ResultsThe first objective of the vaccination strategy was maintenance of the integrity of the healthcare system and critical infrastructure, followed by reduction of morbidity and mortality and reduction of community transmission. In the initial phase, older adult residents in care homes, high-risk health and social care workers, and personal support workers who work in direct contact with coronavirus disease 2019 (COVID-19) patients would be prioritized. Expansion of vaccine supply would allow immunization of older adults not included in phase 1, followed by healthcare workers not previously included and individuals with comorbidities. Further widespread vaccine supply would ensure availability to the extended adult age groups (50–64 years old), critical workers outside the health sector, residents who cannot socially distance, and, eventually, the remaining populations.ConclusionThis survey provides the much needed insight into the decision-making process for vaccine allocation at the national level. However, flexibility in adapting to strategies will be essential, as new information is constantly emerging.  相似文献   
55.
56.
57.
Dihydropyrimidine dehydrogenase (DPYD) is an enzyme that regulates the rate-limiting step in pyrimidine metabolism, especially catabolism of fluorouracil, a chemotherapeutic agent for cancer. In order to determine the genetic distribution of DPYD, we directly sequenced 288 subjects from five ethnic groups (96 Koreans, 48 Japanese, 48 Han Chinese, 48 African Americans, and 48 European Americans). As a result, 56 polymorphisms were observed, including 6 core polymorphisms and 18 novel polymorphisms. Allele frequencies were nearly the same across the Asian populations, Korean, Han Chinese and Japanese, whereas several SNPs showed different genetic distributions between Asians and other ethnic populations (African American and European American). Additional in silico analysis was performed to predict the function of novel SNPs. One nonsynonymous SNP (+199381A > G, Asn151Asp) was predicted to change its polarity of amino acid (Asn, neutral to Asp, negative). These findings would be valuable for further research, including pharmacogenetic and drug responses studies.  相似文献   
58.
59.
Education in dental trauma is extremely important to promote knowledge on the assessment and management of a traumatized tooth. Medical doctors are normally only required to manage the emergency phase of traumatic dental injury (TDI) treatment before referring to a dentist, endodontist or oral and maxillofacial surgeon for continuing care. Medical doctors who possess sufficient theoretical knowledge and are competent enough clinically to handle TDI can provide a higher standard of treatment care and ultimately achieve a better patient outcome. The aim of this literature review was to assess the extent of medical doctors’ knowledge of dental trauma management for injuries in the following four areas: (a) tooth structure; (b) to the supporting bone; (c) to the periodontal tissues; and (d) to the soft tissues. Based on the findings from this literature review, an overall deficiency in knowledge and confidence in managing dental trauma has been identified. Knowledge and understanding to categorize TDI using the same classification of dental injuries commonly used amongst dentists would allow medical doctors to better manage and communicate with dental colleagues concerning referral for further care. If the medical education curriculum provided medical doctors with more information and skills for the management of dental trauma and an understanding of the importance of early management, then more favourable outcomes may prevail for dental trauma patients.  相似文献   
60.
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