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   1277935篇
  免费   99959篇
  国内免费   1987篇
耳鼻咽喉   18437篇
儿科学   44436篇
妇产科学   35035篇
基础医学   182300篇
口腔科学   33645篇
临床医学   111457篇
内科学   258439篇
皮肤病学   28027篇
神经病学   100456篇
特种医学   51241篇
外国民族医学   660篇
外科学   196680篇
综合类   27074篇
现状与发展   1篇
一般理论   377篇
预防医学   95800篇
眼科学   27923篇
药学   94801篇
  2篇
中国医学   2424篇
肿瘤学   70666篇
  2018年   13174篇
  2017年   9983篇
  2016年   10930篇
  2015年   12403篇
  2014年   17195篇
  2013年   26248篇
  2012年   36102篇
  2011年   38139篇
  2010年   22846篇
  2009年   21851篇
  2008年   36696篇
  2007年   39300篇
  2006年   39555篇
  2005年   38488篇
  2004年   37627篇
  2003年   36488篇
  2002年   35825篇
  2001年   64009篇
  2000年   66521篇
  1999年   56428篇
  1998年   15132篇
  1997年   13758篇
  1996年   14199篇
  1995年   13461篇
  1994年   12772篇
  1993年   11803篇
  1992年   44583篇
  1991年   43491篇
  1990年   42251篇
  1989年   40136篇
  1988年   36921篇
  1987年   36252篇
  1986年   33644篇
  1985年   32294篇
  1984年   24143篇
  1983年   20274篇
  1982年   11727篇
  1981年   10697篇
  1980年   9517篇
  1979年   21352篇
  1978年   14825篇
  1977年   12540篇
  1976年   11701篇
  1975年   12634篇
  1974年   14669篇
  1973年   14124篇
  1972年   12951篇
  1971年   11734篇
  1970年   11063篇
  1969年   10036篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Psoriasis is a chronic, inflammatory, immune‐mediated disease. Approximately 30% of patients have disease onset before age 18 years. Psoriasis in children and adolescents may be difficult to control, with subsequent poor quality of life and psychosocial consequences. We describe the case of a 12‐year‐old boy with severe, refractory, chronic plaque psoriasis for 6 years. Various therapeutic regimens including different topical corticosteroids, topical vitamin D analogs, phototherapy, photochemotherapy, systemic therapy with methotrexate, cyclosporin, and combination therapies showed only partial or transient responses with frequent relapses. Because anti‐interleukin‐12/23 agents have been successfully used in adults with psoriasis, ustekinumab was initiated and our patient showed a rapid, excellent, sustained response. No recurrence or flares have been observed after 33 months of follow‐up. This case illustrates that ustekinumab may be an effective and safe therapeutic option in adolescents with psoriasis.  相似文献   
84.
85.
86.
87.
Moderate weight loss improves numerous risk factors for cardiometabolic disease; however, long-term weight loss maintenance (WLM) is often thwarted by metabolic adaptations that suppress energy expenditure and facilitate weight regain. Skeletal muscle has a prominent role in energy homeostasis; therefore, we investigated the effect of WLM and weight regain on skeletal muscle in rodents. In skeletal muscle of obesity-prone rats, WLM reduced fat oxidative capacity and downregulated genes involved in fat metabolism. Interestingly, even after weight was regained, genes involved in fat metabolism were also reduced. We then subjected mice with skeletal muscle lipoprotein lipase overexpression (mCK-hLPL), which augments fat metabolism, to WLM and weight regain and found that mCK-hLPL attenuates weight regain by potentiating energy expenditure. Irrespective of genotype, weight regain suppressed dietary fat oxidation and downregulated genes involved in fat metabolism in skeletal muscle. However, mCK-hLPL mice oxidized more fat throughout weight regain and had greater expression of genes involved in fat metabolism and lower expression of genes involved in carbohydrate metabolism during WLM and regain. In summary, these results suggest that skeletal muscle fat oxidation is reduced during WLM and regain, and therapies that improve skeletal muscle fat metabolism may attenuate rapid weight regain.  相似文献   
88.
89.
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications.  相似文献   
90.
Obtaining accurate assessment data from adolescents in treatment aids clinical decision making and facilitates more accurate outcome evaluations. However, findings could be biased due to underreported substance use and mental health symptoms. This article compares self-reports of youth in non-White matched client–assessor dyads and those in nonmatched dyads. There were no differences on self-reported substance use, but matched youth reported significantly fewer attention deficit/hyperactivity disorder symptoms versus the comparison group. One possible reason for these findings is the effect of in-group stereotype threat. Future studies should examine the potential effect that in-group stereotyping and perceived racism have on the therapeutic relationship.  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