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   1883篇
  免费   85篇
  国内免费   7篇
耳鼻咽喉   16篇
儿科学   90篇
妇产科学   37篇
基础医学   224篇
口腔科学   103篇
临床医学   148篇
内科学   380篇
皮肤病学   39篇
神经病学   108篇
特种医学   170篇
外科学   144篇
综合类   72篇
预防医学   175篇
眼科学   25篇
药学   117篇
  1篇
中国医学   28篇
肿瘤学   98篇
  2024年   7篇
  2023年   9篇
  2022年   29篇
  2021年   46篇
  2020年   23篇
  2019年   43篇
  2018年   40篇
  2017年   40篇
  2016年   49篇
  2015年   39篇
  2014年   77篇
  2013年   89篇
  2012年   118篇
  2011年   149篇
  2010年   86篇
  2009年   66篇
  2008年   78篇
  2007年   118篇
  2006年   68篇
  2005年   69篇
  2004年   46篇
  2003年   39篇
  2002年   43篇
  2001年   30篇
  2000年   41篇
  1999年   34篇
  1998年   54篇
  1997年   47篇
  1996年   34篇
  1995年   22篇
  1994年   27篇
  1993年   23篇
  1992年   20篇
  1991年   15篇
  1990年   21篇
  1989年   22篇
  1988年   26篇
  1987年   26篇
  1986年   20篇
  1985年   21篇
  1984年   8篇
  1983年   17篇
  1982年   13篇
  1981年   12篇
  1980年   10篇
  1978年   12篇
  1977年   10篇
  1976年   13篇
  1975年   7篇
  1971年   4篇
排序方式: 共有1975条查询结果,搜索用时 15 毫秒
31.
Maternal depressive symptoms during pregnancy, and newborn irritability   总被引:10,自引:0,他引:10  
Maternal depression is associated with a wide range of adverse outcomes for children, including poor mother-infant interactions at 3 months post-partum. The aim of this study is to determine whether maternal depressive symptoms during pregnancy are associated with neonatal neurobehavioral functioning, as measured by the Neurologic and Adaptive Capacity Scale. The study population consists of 1,123 mothers and their term infants who were participants in a larger study of maternal health and infant outcomes. Women were administered the Center for Epidemiologic Studies-Depression (CES-D) questionnaire for depressive symptoms during their pregnancy. Their infants were subsequently assessed by a pediatrician blind to their CES-D scores. The CES-D score was associated with unconsolability and excessive crying (p less than 0.01). The higher the mother's CES-D score, the more likely it was that the infant would be unconsolable or cry excessively. Mothers with CES-D scores at the 90th percentile were 2.6 times more likely to have unconsolable newborns, compared with women with CES-D scores at the 10th percentile (95% C.I. = 1.54, 4.23). When potentially confounding variables, such as cigarette smoking, alcohol, marijuana, and cocaine use, poor weight gain, income, birth weight, and other drug use, were controlled, the relationship between CES-D score and newborn unconsolability and excessive crying remain unchanged. The results of this study suggest that the relationship between early childhood problems and maternal depressive symptoms may be part of a sequence that starts with depressive symptoms during pregnancy.  相似文献   
32.
The contributions of arterial baroreceptor and Bezold-Jarisch reflexes, and atrial natriuretic factor (ANF) to the anti-hypertensive effect of the diuretic chlorthalidone were investigated in rats with deoxycorticosterone acetate (DOCA)-salt-induced hypertension. Chlorthalidone (8 mg rat(-1)day(-1)added to food) was given to one group during all 20 days of DOCA (8 mg kg(-1)s.c. twice per week) administration (preventive regimen) and, to another group, 20 days after DOCA treatment was initiated until the 40th day (therapeutic regimen). DOCA caused a significant increase in mean arterial pressure, reduced arterial baroreflex, and increased both the Bezold-Jarisch reflex and pro-ANF converting enzyme activity. Chlorthalidone reversed or prevented the DOCA-salt-induced hypertension, which was accompanied by the normalization of both the arterial baroreflex and the Bezold-Jarisch reflex. Additionally, both preventive and therapeutic regimens with chlorthalidone did cause normalization of the plasma sodium concentration and pro-ANF converting enzyme activity in the left atrium that follows DOCA-salt hypertension. Although it is difficult to determine the relative importance of each of the above regulatory mechanisms altered by chlorthalidone treatment, these data indicate that they may account for the prevention or decrease of DOCA-salt-induced hypertension in rats.  相似文献   
33.
Epignathus is a congenital teratoide tumor in the oral cavity. It is extremely rare and usually lethal. The authors present a case treated successfully. Important aspects of the diagnosis, clinical management and surgical procedures are discussed. Extensive review of the literature is presented.  相似文献   
34.
The influence of extreme environments of volcanic origin over vertebrates and the cellular responses that these may give are almost unknown. The main objectives were to evaluate the exposure of mice to metals in the interior of houses of a small village settled inside a volcanic crater (Furnas, Azores), and the levels of apoptosis and metallothionein in the organs (lung, liver, and kidney) of those animals. Adult mice (Mus musculus) were captured in two areas, one with volcanic activity and the other without it over the last three centuries. In the excised organs, analysis of metals (Al, Cd, Pb, Zn), TUNEL assay for apoptosis, and immunohistochemistry for metallothionein were undertook. Mice from the area with volcanic activity presented higher levels of apoptosis and metallothionein than those from the area without volcanic activity. Such results were in agreement with the differences in metal burdens of the three organs, and interestingly these concentrations were similar to or higher than others found in heavily polluted areas outside the Azores. Thus, there may be a high risk of harmful effects for organisms, including humans, inhabiting areas with volcanism, where hazardous gases and metals in the air are very common during the entire day or even all year round.  相似文献   
35.
Musculoskeletal (MSK) complaints in children and adolescents are common. The differential diagnosis is broad and based predominantly on clinical assessment. The skills both for eliciting history and for examination require understanding of the child/young person's specific emotional and cognitive developmental stage; interpretation of the findings requires knowledge of normal (and abnormal) motor and musculoskeletal growth and development. We specifically describe the different approach, unique skills and knowledge required by all clinicians who assess children and adolescents with MSK complaints; children and adolescents are not 'just little adults'. We emphasize the importance of clinical competence in ensuring that patients with juvenile idiopathic arthritis are diagnosed early and referral to specialist centres is not delayed with consequential suboptimal management and outcome. There is evidence that physician clinical skills in MSK assessment are inadequate, probably as a result of systemic deficiencies in the education process. Current and proposed solutions are discussed.  相似文献   
36.
This article discusses the definitions of transition and models for providing transition care to youth and young adults with rheumatic diseases in the context of differing cultural and health care systems. Issues and questions relating to pediatric rheumatology transition programming are outlined, and a model program of pediatric rheumatology transition is presented.  相似文献   
37.
BACKGROUND: Pulmonary infections can be life threatening for children with neuromuscular diseases who have impaired ability to clear secretions. Intrapulmonary percussive ventilation (IPV) is a pneumatic device that delivers air and aerosol to the lungs at frequencies of 200 to 300 cycles per minute at peak pressures from 20 to 40 cm H(2)O. Anecdotal reports and pilot studies show its safety and effectiveness in mobilizing secretions in patients with cystic fibrosis. OBJECTIVE: To test the hypothesis that IPV used in a pulmonary program for adolescents with neuromuscular disease would reduce the number of days of antibiotic use for pulmonary infection. METHODS: A randomized, controlled study was conducted to compare efficacy of IPV with incentive spirometry (IS) in reducing number of days of antibiotic use in adolescents with neuromuscular disease. The secondary endpoints were the number of respiratory infections, hospitalizations, and school days missed. RESULTS: A total of 18 patients were enrolled (9 IPV, 9 IS). Antibiotic use was significantly higher with IS (24/1000 patient-days) compared with IPV (0/1000 patient-days), (incidence rate ratio, 43; 95% confidence interval, 6-333). The IS group spent more days hospitalized (4.4/1000 patient-days vs 0/1000 patient-days) than the IPV group (incidence rate ratio, 8.5; 95% confidence interval, 1.1-67). The IPV group had 0 episodes of pneumonia or bacterial bronchitis compared with 3 events in the IS group, although this did not meet statistical significance. CONCLUSION: Intrapulmonary percussive ventilation as part of a preventive pulmonary regimen reduced days of antibiotic use and hospitalization for respiratory illness in adolescents with neuromuscular disease.  相似文献   
38.
39.
A recombinant Semliki Forest virus (SFV) RNA construct, SFV1-mCB(2) RNA, was employed for the high-level expression of the murine CB(2) (mCB(2)) cannabinoid receptor in baby hamster kidney cells. Biosynthetic radiolabel incorporation studies in concert with urea-sodium dodecylsulfate-polyacrylamide gel electrophoresis (urea-SDS-PAGE) and western immunoblotting revealed that two major proteins of approximately 26 and 40kDa were produced by the construct. The 40kDa product, but not the 26kDa product, was glycosylated as determined by 2-deoxy-D-glucose incorporation and peptide-N-glycosidase F digestion analysis. Assessment of [3H]CP55940 ([3H]-(-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl)cyclohexanol) binding data for membranes of cells transfected with SFV1-mCB(2) RNA indicated a K(d) of 0.35+/-0.04nM and a B(max) of 24.4+/-2.7pmol/mg. A rank order of binding affinities for cannabinoids, which paralleled that reported for native mCB(2) receptors, was observed. The CB(2) receptor-specific antagonist SR144528 (N-[(1S)-endo-1,3,3-trimethyl bicyclo[2.2.1]heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide) blocked binding of [3H]CP55940, while the CB(1) receptor-specific antagonist SR141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride] had a minimal effect. These results indicate that the recombinant receptor expressed from SFV1-mCB(2) RNA exhibits properties, including ligand binding features, that are consistent with those for the native mCB(2) receptor. However, the presence of both 26 and 40kDa receptor species is consistent with alternative translation from two AUG start sites using the SFV1-mCB(2) RNA expression system.  相似文献   
40.
Due to constant advances in genetic manipulation, the field of public health is faced with the possible emergence of a reductionist genomic emphasis, beyond socio-cultural influences. Under such circumstances, the main focus of public health interventions would shift towards a genomic approach to "individuals" and their "families", to the detriment of their consecrated object - "populations", thereby moving away from the current central priority of efforts (and resources) aimed at reducing ill-health due to socioeconomic inequalities. Even admitting the benefits of genetic knowledge, a new eugenic practice may emerge from the availability of genetic tests on the marketplace aimed at individuals that can afford to consume them.  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