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   304篇
  免费   6篇
  国内免费   2篇
耳鼻咽喉   9篇
儿科学   5篇
妇产科学   26篇
基础医学   55篇
口腔科学   9篇
临床医学   10篇
内科学   75篇
神经病学   35篇
特种医学   20篇
外科学   40篇
综合类   2篇
预防医学   17篇
药学   5篇
肿瘤学   4篇
  2024年   1篇
  2023年   2篇
  2022年   6篇
  2021年   19篇
  2020年   4篇
  2019年   13篇
  2018年   14篇
  2017年   5篇
  2016年   4篇
  2015年   8篇
  2014年   17篇
  2013年   15篇
  2012年   25篇
  2011年   22篇
  2010年   13篇
  2009年   13篇
  2008年   22篇
  2007年   12篇
  2006年   8篇
  2005年   5篇
  2004年   7篇
  2003年   2篇
  2002年   3篇
  1999年   2篇
  1998年   2篇
  1997年   2篇
  1996年   3篇
  1995年   11篇
  1994年   3篇
  1993年   5篇
  1992年   5篇
  1991年   1篇
  1988年   3篇
  1987年   5篇
  1986年   2篇
  1985年   5篇
  1984年   1篇
  1983年   6篇
  1982年   4篇
  1981年   2篇
  1980年   2篇
  1979年   3篇
  1972年   1篇
  1971年   2篇
  1969年   1篇
  1966年   1篇
排序方式: 共有312条查询结果,搜索用时 62 毫秒
1.
Maternal uniparental disomy for the entire chromosome 7 hasso far been reported in three patients with intrauterine andpostnatal growth retardation. Two were detected because theywere homozygous for a cystic fibrosis mutation for which onlythe mother was heterozygous, and one because he was homozygousfor a rare COL1A2 mutation. We investigated 35 patients witheither the Silver-Russell syndrome or primordial growth retardationand their parents with PCR markers to search for uniparentaldisomy 7. Four of 35 patients were found to have maternal disomy,including three with isodisomy and one with heterodisomy. Thedata confirm the hypothetical localization of a maternally imprintedgene (or more than one such gene) on chromosome 7. It is suggestedto search for UPD 7 in families with an offspring with sporadicSilver-Russell syndrome or primordial growth retardation.  相似文献   
2.
3.
In some autosomal imbalance syndromes an additional imbalance interferes with the occurrence of the anomalies typical of the syndrome itself. For example, polydactyly was found in patients with “pure” del(3p) more frequently (11/23) than in patients where these deletions were associated with different partial trisomies (2/28). The opposite situation was shown in del(7q) syndrome where various defects of the holoprosencephalic group were found to be rarer in patients with “pure” deletions, than in cases with simultaneous occurrence of various partial trisomies. It suggests the importance of gene interaction in determining the phenotypic picture of autosomal imbalance syndromes. © 1993 Wiley-Liss, Inc.  相似文献   
4.
5.
Six familial cases of the Beemer–Langer syndrome (BLS) were analyzed to further elucidate the spectrum and frequency of anomalies observed in this disorder. Preaxial polydactyly was found in 3/6 affected sibs, and, therefore, its frequency previously may have been underestimated. Some patients, described as infants affected with the Majewski syndrome (MS) or “atypical” short rib-poly-dactyly conditions, may indeed have BLS. A high frequency of brain defects (16/26) and cleft tongue, oral frenula, and/or natal teeth (13/29) widens the list of typical findings in this syndrome. The specific type of tibial defect seems to be the most important discrimination of the MS and the BLS. © 1994 Wiley-Liss, Inc.  相似文献   
6.
Leptin is an adipocyte-secreted hormone which plays a key role in energy homeostasis. Recent “proof of concept” studies involving leptin administration to humans support its critical role in regulating energy homeostasis, neuroendocrine and immune function as well as insulin resistance in states of energy/ caloric deprivation. Moreover, interventional studies in leptin deficient children and observational studies in normal girls and boys support a role for leptin as a permissive factor for the initiation of puberty in children. The potential clinical usefulness of leptin in several disease states in children and adolescents, including hypothalamic amenorrhea, eating disorders and syndromes of insulin resistance is still under investigation.  相似文献   
7.
8.
G Iosif  J Fleischman  R Chitkara 《Chest》1991,99(6):1538-1539
Empyema developing seven weeks after craniotomy in a 62-year-old black woman with an ipsilateral ventriculopleural (V-PL) shunt is described. Infection of the pleural space presumably resulted from transfer of organisms from a proximal V-PL shunt infection to the thorax. Empyema resulting from V-PL shunt infection has not previously been reported. Pleural effusions in patients with V-PL shunts must be considered as a potential site of infection with possible development of empyema.  相似文献   
9.
Antibodies directed against fetal brain proteins of 37 and 73 kDa molecular weight are found in approximately 12% of mothers who have children with autism spectrum disorder (ASD), but not in mothers of typically developing children. This finding has raised the possibility that these immunoglobulin G (IgG) class antibodies cross the placenta during pregnancy and impact brain development, leading to one form of ASD. We evaluated the pathogenic potential of these antibodies by using a nonhuman primate model. IgG was isolated from mothers of children with ASD (IgG-ASD) and of typically developing children (IgG-CON). The purified IgG was administered to two groups of female rhesus monkeys (IgG-ASD; n=8 and IgG-CON; n=8) during the first and second trimesters of pregnancy. Another control group of pregnant monkeys (n=8) was untreated. Brain and behavioral development of the offspring were assessed for 2 years. Behavioral differences were first detected when the macaque mothers responded to their IgG-ASD offspring with heightened protectiveness during early development. As they matured, IgG-ASD offspring consistently deviated from species-typical social norms by more frequently approaching familiar peers. The increased approach was not reciprocated and did not lead to sustained social interactions. Even more striking, IgG-ASD offspring displayed inappropriate approach behavior to unfamiliar peers, clearly deviating from normal macaque social behavior. Longitudinal magnetic resonance imaging analyses revealed that male IgG-ASD offspring had enlarged brain volume compared with controls. White matter volume increases appeared to be driving the brain differences in the IgG-ASD offspring and these differences were most pronounced in the frontal lobes.  相似文献   
10.
ABSTRACT

Objective: The purpose of this study was to assess enamel gloss changes induced by orthodontic bracket bonding with a light-cured composite or a light-cured resin-reinforced glass ionomer cement.

Setting: The Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens, Greece.

Design: Laboratory study.

Methods: A total of twenty extracted upper human first premolars were included in this study and each tooth served as a control for itself. Their buccal surfaces were subjected to 60o-angle gloss measurement (G%60) with a standardized and secure repeated analysis of the same site. After baseline evaluation, a bracket was bonded on the buccal surface of each tooth. Half of the specimens were bonded with acid-etching and a light-cured composite whereas the other half with a light-cured resin-reinforced glass ionomer cement without prior enamel conditioning. Gloss measurements were repeated after bracket debonding and removal of the composite/glass ionomer cement with an 18-fluted carbide bur. Gloss differences between the two measurement conditions (baseline and post-debonding) were analyzed through linear regression with standard errors derived using the bootstrap method. Level of significance was set at a?<?0.05.

Results: A statistically significant difference was detected between the tested groups for the outcome of interest. Teeth bonded with light-cured composite exhibited larger enamel gloss changes as compared to resin-reinforced glass ionomer cement (β?=?0.74; 95% CIs: 0.10, 1.38; p?=?0.02).

Conclusions: Bracket bonding with two common bonding protocols (acid-etching with a light-cured composite vs. no etching with resin reinforced glass-ionomer cement) and subsequently debonding and adhesive removal with an 18-fluted carbide bur induced enamel gloss changes.  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