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   2443篇
  免费   154篇
  国内免费   11篇
耳鼻咽喉   12篇
儿科学   35篇
妇产科学   27篇
基础医学   288篇
口腔科学   97篇
临床医学   163篇
内科学   603篇
皮肤病学   73篇
神经病学   335篇
特种医学   95篇
外科学   290篇
综合类   8篇
预防医学   75篇
眼科学   22篇
药学   165篇
中国医学   5篇
肿瘤学   315篇
  2023年   23篇
  2022年   21篇
  2021年   56篇
  2020年   32篇
  2019年   46篇
  2018年   69篇
  2017年   45篇
  2016年   64篇
  2015年   89篇
  2014年   116篇
  2013年   124篇
  2012年   165篇
  2011年   176篇
  2010年   104篇
  2009年   100篇
  2008年   150篇
  2007年   165篇
  2006年   164篇
  2005年   170篇
  2004年   168篇
  2003年   142篇
  2002年   133篇
  2001年   27篇
  2000年   16篇
  1999年   26篇
  1998年   19篇
  1997年   19篇
  1996年   14篇
  1995年   22篇
  1994年   12篇
  1993年   15篇
  1992年   8篇
  1991年   11篇
  1990年   10篇
  1989年   9篇
  1988年   4篇
  1987年   7篇
  1986年   7篇
  1985年   4篇
  1984年   11篇
  1983年   5篇
  1982年   9篇
  1981年   7篇
  1980年   3篇
  1979年   2篇
  1976年   2篇
  1975年   3篇
  1974年   3篇
  1972年   2篇
  1937年   1篇
排序方式: 共有2608条查询结果,搜索用时 15 毫秒
1.
Journal of Molecular Medicine - Chronic exposure to high levels of particulate matter (PM) is correlated to a higher prevalence of cardio-metabolic disturbances. Adipose tissue represents a pivotal...  相似文献   
2.
The development of patient‐specific induced pluripotent stem cells (iPSCs) offered interesting insights in modeling the pathogenesis of Charcot‐Marie‐Tooth (CMT) disease and thus we decided to explore the phenotypes of iPSCs derived from a single CMT patient carrying a mutant ATP1A1 allele (p.Pro600Ala). iPSCs clones generated from CMT and control fibroblasts, were induced to differentiate into neural precursors and then into post‐mitotic neurons. Control iPSCs differentiated into neuronal precursors and then into post‐mitotic neurons within 6‐8 days. On the contrary, the differentiation of CMT iPSCs was clearly defective. Electrophysiological properties confirmed that post‐mitotic neurons were less mature compared to the normal counterpart. The impairment of in vitro differentiation of CMT iPSCs only concerned with the neuronal pathway, because they were able to differentiate into mesendodermal cells and other ectodermal derivatives. ATP1A1 was undetectable in the few neuronal cells derived from CMT iPSCs. ATP1A1 gene mutation (p.Pro600Ala), responsible for a form of axonal CMT disease, is associated in vitro with a dramatic alteration of the differentiation of patient‐derived iPSCs into post‐mitotic neurons. Thus, the defect in neuronal cell development might lead in vivo to a decreased number of mature neurons in ATP1A1‐CMT disease.  相似文献   
3.
4.
BackgroundCondylar cartilage acts as a centre of craniofacial complex growth and magnetic resonance imaging (MRI) is the most suitable examination to differentiate tissues and identify pathological conditions of TMJ. Condylar growth disturbance can alter the maxillofacial morphology, including occlusal relationship, and the affected children may not present symptoms. Although TMJ in children is similar to that in adults, the anterior condylar inclination is straight and increases with age, presenting slight condylar flattening and slight contrast enhancement.ObjectiveThe present work aimed to review the literature focussing to assess how MRI and the development of TMJ can contribute to orthopaedic/orthodontic diagnosis in growing patients.Main resultsMRI can also complement the predictive diagnosis of growth in which the image of a double contour of the condyle reveals proliferation of cartilage cells with immature ossification. Considering that orthodontic therapy usually begins after eruption of permanent teeth, the moment of alternation of the double contour-like structure is close or coincident with the eruption of upper second molars.ConclusionClinically, the advantage of diagnosis of double contour is not to use any ionizing radiation related to scan in these subjects. Therefore, MRI could be a choice for the follow-up of growing patients.  相似文献   
5.
6.
7.
ObjectiveThe aim of this study was to create and validate an abbreviated version of the Spanish Transsexual Voice Questionnaire for Male-to-Female Transsexuals (SvTVQMtF).SettingThe study was conducted by two referral hospitals for voice feminization surgery and by a university department of psychology and speech therapy, all in Spain.Subjects and methodsWe prospectively studied 51 male-to-female transsexuals who underwent voice feminization surgery between January 2017 and December 2018. The SvTVQMtF was completed before and after surgery, and the 10 items with the greatest variation were selected by clinical consensus of an expert panel to develop the short version of the SvTVQMtF (SvTVQMtF-10). The correlation between the total score and the score for each item on the SvTVQMtF and the SvTVQMtF-10 was studied. The internal consistency of the SvTVQMtF-10 was analysed.ResultsGood correlation (Pearson coefficient above .90) was found between the two questionnaires. A significant correlation was found between the total SvTVQMtF-10 score and the score for each item. A significant negative correlation was found between the SvTVQMtF and fundamental frequency after voice feminization surgery. Cronbach's α was .79.ConclusionThe SvTVQMtF-10 is a valid short version of the SvTVQMtF and can be used to quantify voice-related quality of life in MtF transsexuals.  相似文献   
8.
MRI leverages multiple modes of contrast to characterize stroke. High‐magnetic‐field systems enhance the performance of these MRI measurements. Previously, we have demonstrated that individually sodium and stem cell tracking metrics are enhanced at ultrahigh field in a rat model of stroke, and we have developed robust single‐scan diffusion‐weighted imaging approaches that utilize spatiotemporal encoding (SPEN) of the apparent diffusion coefficient (ADC) for these challenging field strengths. Here, we performed a multiparametric study of middle cerebral artery occlusion (MCAO) biomarker evolution focusing on comparison of these MRI biomarkers for stroke assessment during sub‐acute recovery in rat MCAO models at 21.1 T. T2‐weighted MRI was used as the benchmark for identification of the ischemic lesion over the course of the study. The number of MPIO‐induced voids measured by gradient‐recalled echo, the SPEN measurement of ADC, and 23Na MRI values were determined in the ischemic area and contralateral hemisphere, and relative performances for stroke classification were compared by receiver operator characteristic analysis. These measurements were associated with unique time‐dependent trajectories during stroke recovery that changed the sensitivity and specificity for stroke monitoring during its evolution. Advantages and limitations of these contrasts, and the use of ultrahigh field for multiparametric stroke assessment, are discussed.  相似文献   
9.
10.
There is an epidemic of obesity starting about 1980 in both developed and undeveloped countries definitely associated with multiple etiologies. About 670 million people worldwide are obese. The incidence of obesity has increased in all age groups, including children. Obesity causes numerous diseases and the interaction between genetic, metabolic, social, cultural and environmental factors are possible cofactors for the development of obesity. Evidence emerging over the last 20 years supports the hypothesis that viral infections may be associated with obesity in animals and humans. The most widely studied infectious agent possibly linked to obesity is adenovirus 36 (Adv36). Adv36 causes obesity in animals. In humans, Adv36 associates with obesity both in adults and children and the prevalence of Adv36 increases in relation to the body mass index. In vivo and in vitro studies have shown that the viral E4orf1 protein (early region 4 open reading frame 1, Adv) mediates the Adv36 effect including its adipogenic potential. The Adv36 infection should therefore be considered as a possible risk factor for obesity and could be a potential new therapeutic target in addition to an original way to understand the worldwide rise of the epidemic of obesity. Here, the data indicating a possible link between viral infection and obesity with a particular emphasis to the Adv36 will be reviewed.  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