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   1992225篇
  免费   149967篇
  国内免费   3441篇
耳鼻咽喉   25337篇
儿科学   65131篇
妇产科学   53468篇
基础医学   275578篇
口腔科学   52736篇
临床医学   174592篇
内科学   390261篇
皮肤病学   37755篇
神经病学   166885篇
特种医学   80799篇
外国民族医学   484篇
外科学   306227篇
综合类   45470篇
现状与发展   3篇
一般理论   836篇
预防医学   159035篇
眼科学   44674篇
药学   145391篇
  7篇
中国医学   4050篇
肿瘤学   116914篇
  2019年   14955篇
  2018年   41269篇
  2017年   32593篇
  2016年   37098篇
  2015年   20827篇
  2014年   28559篇
  2013年   42162篇
  2012年   64071篇
  2011年   81036篇
  2010年   53198篇
  2009年   44753篇
  2008年   76850篇
  2007年   83135篇
  2006年   61079篇
  2005年   61820篇
  2004年   61815篇
  2003年   60528篇
  2002年   56652篇
  2001年   78011篇
  2000年   80454篇
  1999年   68710篇
  1998年   20607篇
  1997年   18818篇
  1996年   18328篇
  1995年   17976篇
  1994年   16811篇
  1993年   15727篇
  1992年   56664篇
  1991年   54948篇
  1990年   53619篇
  1989年   51817篇
  1988年   48180篇
  1987年   47546篇
  1986年   45208篇
  1985年   43773篇
  1984年   33167篇
  1983年   28604篇
  1982年   17413篇
  1981年   15611篇
  1979年   31167篇
  1978年   21790篇
  1977年   18344篇
  1976年   17296篇
  1975年   17994篇
  1974年   21934篇
  1973年   21040篇
  1972年   19180篇
  1971年   18032篇
  1970年   16560篇
  1969年   15478篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
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   
152.
153.
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   
154.
An association between juvenile xanthogranuloma (JXG), neurofibromatosis type 1 (NF1), and juvenile myelomonocytic leukemia (JMML) has been described in the literature but has only been documented in approximately 20 cases. We diagnosed a patient with NF1 at 25 months of age, before any cutaneous stigmata of this disease had appeared, because we decided to screen for the NF1 gene mutation because of his presentation with multiple JXGs and moderate macrocephaly (2.5 standard deviations) at 9 months of age and JMML diagnosed at 20 months of age. The child is well today after treatment with chemotherapy and allogenic bone marrow transplantation. With increased awareness, patients with JXG and NF1 who develop symptoms possibly related to JMML, such as paleness, skin bleeding, cough, unexplained fever, and hepatosplenomegaly, should be further evaluated. We also emphasize that multiple JXG lesions can be an early marker of NF1.  相似文献   
155.
Advancing nanomedicines from concept to clinic requires integration of new science with traditional pharmaceutical development. The medical and commercial success of nanomedicines is greatly facilitated when those charged with developing nanomedicines are cognizant of the unique opportunities and technical challenges that these products present. These individuals must also be knowledgeable about the processes of clinical and product development, including regulatory considerations, to maximize the odds for successful product registration. This article outlines these topics with a goal to accelerate the combination of academic innovation with collaborative industrial scientists who understand pharmaceutical development and regulatory approval requirements—only together can they realize the full potential of nanomedicines for patients.  相似文献   
156.
157.
158.
159.
On 8 April 2014, a US jury ordered Takeda and Eli Lilly to pay $9 bn in punitive damages after finding that they had concealed the cancer risks associated with pioglitazone. By contrast, on 28 August 2014, the long‐awaited outcome of the 10‐year Kaiser Permanente Northern California study was announced. That study was specifically designed to investigate whether patients exposed to pioglitazone were at an increased risk of bladder cancer and found no association; thus, at last, the controversial issue has been resolved. A review, in retrospect, of the story of the proposed link between pioglitazone and bladder cancer reveals flaws at every stage. In 2012, a BMJ editorial, in keeping with some other contemporary reports, stated ‘it can confidently be assumed that pioglitazone increases the risk of bladder cancer’. Examination of the information which led to such a statement shows that: 1) the pre‐clinical findings of bladder cancer in male rats is not indicative of human risk; 2) there is no association between bladder cancer and pioglitazone in randomized controlled trials, once cases that could not plausibly be related to treatment are removed; and 3) the observational studies that have suggested a link have over‐extrapolated from the data: pioglitazone‐treated patients had more risk factors for bladder cancer than those not treated with pioglitazone. Meanwhile careful study of randomized controlled trials shows evidence of cardiovascular benefit from pioglitazone in Type 2 diabetes, a condition which results, more than anything, in premature cardiovascular death and morbidity.  相似文献   
160.
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