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   2590013篇
  免费   190046篇
  国内免费   7583篇
耳鼻咽喉   34396篇
儿科学   85394篇
妇产科学   71795篇
基础医学   364746篇
口腔科学   69731篇
临床医学   234795篇
内科学   516429篇
皮肤病学   62670篇
神经病学   214582篇
特种医学   100435篇
外国民族医学   736篇
外科学   388198篇
综合类   50331篇
现状与发展   5篇
一般理论   969篇
预防医学   195845篇
眼科学   56640篇
药学   188653篇
  8篇
中国医学   5347篇
肿瘤学   145937篇
  2021年   20332篇
  2019年   20986篇
  2018年   29745篇
  2017年   22904篇
  2016年   26530篇
  2015年   29894篇
  2014年   41023篇
  2013年   61123篇
  2012年   81350篇
  2011年   85635篇
  2010年   51661篇
  2009年   49774篇
  2008年   79980篇
  2007年   84737篇
  2006年   86467篇
  2005年   82549篇
  2004年   79484篇
  2003年   76671篇
  2002年   73950篇
  2001年   128492篇
  2000年   131390篇
  1999年   110589篇
  1998年   31368篇
  1997年   28017篇
  1996年   28288篇
  1995年   27443篇
  1994年   25130篇
  1993年   23457篇
  1992年   85194篇
  1991年   81591篇
  1990年   78796篇
  1989年   76087篇
  1988年   69427篇
  1987年   67972篇
  1986年   63519篇
  1985年   60478篇
  1984年   44899篇
  1983年   37861篇
  1982年   22383篇
  1981年   19910篇
  1979年   38892篇
  1978年   27376篇
  1977年   23168篇
  1976年   21422篇
  1975年   22770篇
  1974年   26749篇
  1973年   25335篇
  1972年   23741篇
  1971年   21945篇
  1970年   20171篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Safety and efficacy of botulinum toxin type A following long-term use   总被引:2,自引:0,他引:2  
Botulinum toxin serotype A (BoNT-A) has long heritage of use leading to confidence in its safety and efficacy. The application of BoNT-A does not lead to persistent histological changes in the nerve terminal or the target muscle. Clinical trials defined the safety and tolerability profile of BoNT-A across common therapeutic indications and showed an incidence of adverse events of approximately 25% in the BoNT-A-treated group compared with 15% in the control group. Focal weakness was the only adverse event to occur more often following BoNT-A treatment. Long-term BoNT-A administration has been assessed in various treatment settings, with the level and duration of BoNT-A efficacy response being maintained over repeated rounds of injection with no major safety concerns. The treatment of children with cerebral palsy often require long-term, repeated, multimuscle BoNT-A injections that lead to the administration of comparably higher toxin doses. Despite the high total body doses used, their distribution over multiple muscles and injection sites means that systemic side effects are rare. Recent formulation changes have reduced the incidence of antibody development following treatment with BOTOX®. These findings show long-term BoNT-A treatment to be both safe and efficacious for a wide variety of indications.  相似文献   
994.
995.
996.
997.
998.
999.
This study examined the ability of PCR to amplify Leishmania DNA, stored on Giemsa-stained slides, from American cutaneous leishmaniasis (ACL) patients. In total, 475 slides stored for up to 36 years were obtained from an outpatient clinic in a Brazilian ACL-endemic region, and Leishmania DNA was amplified from 395 (83.2%) of the DNA samples using primers specific for the minicircle kinetoplast DNA. Restriction fragment length polymorphism analysis of these amplicons demonstrated that Leishmania (Viannia) braziliensis was the only species present in these samples. The results demonstrated that archived Giemsa-stained slides can provide a Leishmania DNA source for performing clinical and epidemiological studies of leishmaniasis.  相似文献   
1000.
In the last 20 years, cases of human cryptococcosis, have increased in immunocompromised patients. In several instances, the cases have been associated with the exposure of the patients to bird droppings. In order to investigate birds of prey as potential carriers and spreaders of Cryptococcus neoformans and other yeasts of importance in human infections, 182 swab samples were collected from the cloacae of several species of birds of prey (Group I) and 32 faecal samples from aviaries in which the birds were housed (Group II). Samples were also taken from digestive tract of 60 dead birds (Group III). A total of 454 samples were cultured from which 215 colonies of yeastlike fungi were recovered and identified. Cryptococcusneoformans var. grubii was isolated from three cloacae samples (4.8%) collected from Falco tinnunculus and from one sample (3.1%) obtained from Buteo buteo, as well as from samples collected at the aviaries in which these birds were kept. Overall, 18 samples (9.9%) from Group I, 13 (40.6%) from Group II, 12 crops (20%), three proventriculi (5%) and 12 cloacae (20%) from Group III yielded positive cultures for yeasts. The results indicate that birds of prey and in particular, F. tinnunculus and B. buteo, may act as carriers and spreaders of C. neoformans and other zoonotic yeasts.  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