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   71732篇
  免费   5060篇
  国内免费   200篇
耳鼻咽喉   531篇
儿科学   2116篇
妇产科学   1174篇
基础医学   9878篇
口腔科学   1500篇
临床医学   7510篇
内科学   15163篇
皮肤病学   983篇
神经病学   6829篇
特种医学   2322篇
外国民族医学   1篇
外科学   10089篇
综合类   902篇
一般理论   72篇
预防医学   6398篇
眼科学   1732篇
药学   4910篇
  1篇
中国医学   80篇
肿瘤学   4801篇
  2023年   343篇
  2022年   288篇
  2021年   1404篇
  2020年   840篇
  2019年   1364篇
  2018年   1662篇
  2017年   1247篇
  2016年   1358篇
  2015年   1587篇
  2014年   2368篇
  2013年   3216篇
  2012年   5247篇
  2011年   5378篇
  2010年   3003篇
  2009年   2677篇
  2008年   4886篇
  2007年   5352篇
  2006年   5254篇
  2005年   4980篇
  2004年   4783篇
  2003年   4330篇
  2002年   4216篇
  2001年   587篇
  2000年   428篇
  1999年   657篇
  1998年   907篇
  1997年   762篇
  1996年   642篇
  1995年   612篇
  1994年   496篇
  1993年   466篇
  1992年   364篇
  1991年   320篇
  1990年   277篇
  1989年   255篇
  1988年   273篇
  1987年   227篇
  1986年   242篇
  1985年   246篇
  1984年   319篇
  1983年   330篇
  1982年   387篇
  1981年   365篇
  1980年   340篇
  1979年   198篇
  1978年   238篇
  1977年   181篇
  1976年   134篇
  1975年   103篇
  1974年   110篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Vascular complications in closed clavicular fractures are uncommon, with an incidence of only 0.4%. Subclavian artery injury can present acutely or can have a delayed presentation with arm ischemia. We report the case of an undetected subclavian pseudoaneurysm in a patient with a nonunion fracture clavicle who was referred with persistent ischemia following attempted brachial embolectomy at another center, along with a review of literature to support the hypothesis that in addition to repair of the aneurysm, treatment of the psuedarthrosis by fixation of the clavicle is essential.  相似文献   
993.
The technique of arthroscopic subscapularis repair continues to evolve. A three-sided subscapularis release (e.g. anterior, posterior, superior) is commonly advocated for improving tendon excursion to bone. However, a lateral release is commonly required as well, particularly for full thickness, upper subscapularis tears and full thickness, complete subscapularis tears. We describe the techniques to identify and release the lateral subscapularis border, which aids in the completion of other releases.  相似文献   
994.
Deep-sea cold seeps support diverse communities that include vestimentiferan tubeworms of the genus Escarpia. To investigate population structure to understand how deep-sea communities are established, several polymorphic microsatellites were developed using 454 pyrosequencing. Eleven and sixteen loci were identified in Escarpia laminata (n = 129) and Escarpia southwardae (n = 80). Additionally, the amplification of microsatellites is expected to be successful in closely related species and can help resolve their phylogenetic relationships. Nine of the E. laminata loci were amplified across three Escarpia species (n = 229). Four of the twenty-eight loci deviated from Hardy–Weinburg Equilibrium and no linkage disequilibrium was found in the loci tested here.  相似文献   
995.
Lack of cell surface glycosylphosphatidylinositol (GPI)‐anchored protein(s) has been used as a reporter of Pig‐a gene mutation in several model systems. As an extension of this work, our laboratory initiated development of an in vitro mutation assay based on the flow cytometric assessment of CD90.2 expression on the cell surface of the mouse lymphoma cell line L5178Y/Tk+/?. Cells were exposed to mutagenic and nonmutagenic compounds for 24 hr followed by washout and incubation for an additional 7 days. Following this mutant manifestation time, cells were labeled with fluorescent antibodies against CD90.2 and CD45 antigens. These reagents indicated the presence of GPI‐anchored proteins and general cell surface membrane receptor integrity, respectively. Instrument set‐up was aided by parallel processing of a GPI anchor‐deficient subclone. Results show that the mutagens reproducibly caused increased frequencies of mutant phenotype cells, while the nonmutagens did not. Further modifications to the method, including application of a viability dye and an isotype control for instrument set‐up, were investigated. As a means to verify that the GPI‐anchored protein‐negative phenotype reflects bona fide Pig‐a gene mutation, sequencing was performed on 38 CD90.2‐negative L5178Y/Tk+/? clones derived from cultures treated with ethyl methanesulfonate. All clones were found to have mutation(s) within the Pig‐a gene. The continued investigation of L5178Y/Tk+/? cells, CD90.2 labeling, and flow cytometric analysis as the basis of an in vitro mutation assay is clearly supported by this work. These data also provide evidence of the reliability of using GPI anchor‐deficiency as a valid reporter of Pig‐a gene mutation. Environ. Mol. Mutagen. 59:18–29, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
996.
Mental illness affects millions of people around the world, and yet support, advocacy, and acceptance of people with psychological disabilities is lacking. The stigma of mental illness hinders those who want and need help from getting it, which only perpetuates the problem. The purpose of this study was to identify those factors that have predictive value for opinions of mental illness. Mechanical Turk was used to distribute the Opinions of Mental Illness scale along with a demographics survey. Taking part in the initial survey were 195 people (82 females) of Indian descent. Utilizing a backwards stepwise regression, we constructed a model that included the four most influential factors. Gender, political affiliation, parental nurturing, and age emerged as the best predictors of opinions of mental illness within the Indian population.  相似文献   
997.
An important component of the New York State Refugee Health Program’s (NYSRHP) mission is to ensure refugees with identified medial conditions are referred to primary and specialty care. A programmatic evaluation was conducted to assess the completion rate for primary care referral appointments made during the initial domestic health assessment among refugees in NYS (exclusive of New York City). Upon arrival in NYS, refugees may receive a domestic health assessment by one of NYSRHP contracted providers. As part of the assessment, referrals for primary and specialty care may be assigned. From July 2010 to June 2011, 69 % of NYS-bound refugees that received a primary care referral by a NYSRHP contracted provider completed their appointment.  相似文献   
998.
999.
The anterosuperior rotator interval portal for SLAP repair anchor placement is the perfect balance between obtaining the proper anchor trajectory and respecting the rotator cuff integrity.  相似文献   
1000.
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