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   19964篇
  免费   1690篇
  国内免费   371篇
耳鼻咽喉   199篇
儿科学   450篇
妇产科学   418篇
基础医学   2838篇
口腔科学   475篇
临床医学   2595篇
内科学   3561篇
皮肤病学   1356篇
神经病学   1039篇
特种医学   990篇
外国民族医学   3篇
外科学   1267篇
综合类   1367篇
现状与发展   3篇
一般理论   5篇
预防医学   2157篇
眼科学   206篇
药学   1578篇
  5篇
中国医学   116篇
肿瘤学   1397篇
  2024年   40篇
  2023年   385篇
  2022年   759篇
  2021年   972篇
  2020年   982篇
  2019年   911篇
  2018年   810篇
  2017年   768篇
  2016年   813篇
  2015年   839篇
  2014年   1238篇
  2013年   1519篇
  2012年   1023篇
  2011年   1122篇
  2010年   864篇
  2009年   870篇
  2008年   828篇
  2007年   831篇
  2006年   766篇
  2005年   597篇
  2004年   562篇
  2003年   506篇
  2002年   437篇
  2001年   371篇
  2000年   304篇
  1999年   323篇
  1998年   279篇
  1997年   281篇
  1996年   254篇
  1995年   208篇
  1994年   177篇
  1993年   166篇
  1992年   174篇
  1991年   133篇
  1990年   111篇
  1989年   120篇
  1988年   109篇
  1987年   91篇
  1986年   60篇
  1985年   90篇
  1984年   73篇
  1983年   46篇
  1982年   41篇
  1981年   37篇
  1980年   41篇
  1979年   21篇
  1978年   13篇
  1977年   18篇
  1976年   18篇
  1975年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Genetic carrier testing of children is usually not recommended. However, there are no data concerning long-term psychological consequences, experience, and satisfaction of those tested as well as their recall of the test results. We evaluated these items retrospectively 10–24 years after carrier testing performed in childhood. Study material comprised 25 families with aspatylglucosaminuria (AGU), an autosomal recessive disorder, with 35 healthy sibs from all parts of Finland tested for carriership during childhood between 1973 and 1987. Of these sibs, 25 participated in our study. The questionnaire comprised multiple-choice and open-ended questions. The psychosocial well-being of the study subjects measured by the RAND 36 item Health Survey 1.0 (RAND) was, in general, at least as good as that of controls, and showed no significant differences between carriers and non-carriers (p>0.154). All tested individuals were satisfied with the fact that they had been tested and stated that the decision to perform carrier testing on a child can be made by the parents. Of the 25 tested, 23 knew and understood their test result correctly at the time of our study. Most of the tested individuals (60%) stated that the best time for carrier testing would be in the childhood or in the teen years.
This study indicates that carrier testing in childhood for an autosomal recessive disorder (AGU) had caused no measurable disturbance of quality of life in adulthood, and those tested reported being satisfied. However, we do not recommend testing in childhood, as the result is not needed prior to the time for reproductive decisions.  相似文献   
52.
Analysis of HLA DRB1 and DQB1 Bam HI RFLPs revealed four DRB1 (4.8, 5.2, 6.0 and 7.0 kb) fragments and a 3.2 kb DQB1 fragment to be significantly increased in Caucasians with seropositive RA compared to healthy individuals. The 4.8, 5.2 and 7.0 kb DRB1 fragments were found in 86.5% of RA patients and in 56% of the controls (p = 10(-3), relative risk (RR) = 5.0), while the 6.0 kb fragment was found in 79% of RA patients compared to 32% of controls (p = 2 x 10(-5), RR = 8.0). The 3.2 kb DQB1 fragment was observed in 63.5% of RA patients versus 38.0% of controls (p = 10(-2), RR = 2.8). Analysis of these fragments relative to HLA phenotypes revealed that the 4.8, 5.2 and 7.0 kb DRB1 fragments were strongly correlated with DR4, -7, -9 and -w53 serotypes, the 6.0 kb RFLP with DR4 and the 3.2 kb DQB1 fragment with DR1 and DQw1. Using probes specific for the 5' or 3' regions of the DRB1 gene, the 5.2 and 6.0 kb DRB RFLPs were mapped to the 5' end and the 4.8 and 7.0 kb RFLPs to the 3' end of the DRB1 gene. A probe generated from the second exon of the DRB4 (DRw53) gene recognized only the 5.2 and the 6.0 kb RFLPs corroborating the 5' location of these RFLPs. Family studies further confirmed that these RFLP's segregated with HLA phenotypes.  相似文献   
53.
Bloom syndrome is more common in individuals of Ashkenazi Jewish descent than in any other population, and one particular mutation in the Bloom syndrome gene,blmAsh,is homozygous in nearly all Ashkenazi Jewish persons with Bloom syndrome. We have determined the frequency ofblmAshin 1491 Ashkenazi Jewish persons with no known history of Bloom syndrome and found that 1 in 107 persons was heterozygous. Although not common, genetic screening for Bloom syndrome is feasible in this population.  相似文献   
54.
55.
An exercise test was performed in 455 patients in the thirdweek after acute myocardial infarction (AMI). One hundred andseventeen (26%) of them were considered as having a complicatedAMI. During a follow-up of 4.5 years their mortality was 49%vs 23% in the remaining patients with uncomplicated AMI. Thesurvival of the patients was assessed in each clinical groupin relation to various exercise variables. Exercise-inducedST-segment depression, irrespective of its degree, did not discriminatesignificantly between dead and living patients in any of theclinical groups. A high value of the rise of the pressure-rateproduct (PRP) from rest to maximal exercise (dPRP) and absenceof significant exercise-induced ventricular arrhythmias identifiedin both clinical groups patients with a very low risk of dying.A low dPRP and/or occurrence of significant ventricular arrhythmiasidentified a relatively high risk in uncomplicated AMI patientsand a very high risk of dying in complicated A MI subjects.The difference in the probability of survival between low-riskand high-risk patients was highly significant in each clinicalgroup (P<0.0001 in uncomplicated, and <0.005 in complicatedAMI, respectively).  相似文献   
56.
Twenty-four patients with stable exercise-induced angina pectorisentered a double-blind cross-over study. Isosorbide-5-mononitrate(5-ISMN) 60 mg in a controlled release formulation (Durules®)given once daily was compared with identical placebo. The exercisetolerance was determined by bicycle ergometry before and 3 hafter a single dose of 5-ISMN and following one week's treatmentwith 5-ISMN and placebo. Nineteen patients completed the study.Exercise tolerance until the onset of chest pain and until 1mm ST segment depression increased significantly 3 h after dose.The same increase was seen both after a single dose and thesame dose under steady-state conditions. No increase was seenwith placebo. The heart rate and systolic blood pressure reactionsin the standing position were less pronounced 3 h after dosein steady-state than after a single dose of 5-ISMN. Headachewas the only bothersome side-effect reported. The study demonstratesthat 60 mg 5-ISMN in a Durules® formulation given once dailyhas a significant anti-anginal effect and that tolerance doesnot develop.  相似文献   
57.
58.
This paper presents a mathematical model of blood volume kinetics and renal function in response to burn injury and resuscitation, which is applicable to the development and non-clinical testing of burn resuscitation protocols and algorithms. Prior mathematical models of burn injury and resuscitation are not ideally suited to such applications due to their limited credibility in predicting blood volume and urinary output observed in wide-ranging burn patients as well as in incorporating contemporary knowledge of burn pathophysiology. Our mathematical model consists of an established multi-compartmental model of blood volume kinetics, a hybrid mechanistic-phenomenological model of renal function, and novel lumped-parameter models of burn-induced perturbations in volume kinetics and renal function equipped with contemporary knowledge on burn-related physiology and pathophysiology. Using the dataset collected from 16 sheep, we showed that our mathematical model can be characterized with physiologically plausible parameter values to accurately predict blood volume kinetic and renal function responses to burn injury and resuscitation on an individual basis against a wide range of pathophysiological variability. Pending validation in humans, our mathematical model may serve as an effective basis for in-depth understanding of complex burn-induced volume kinetic and renal function responses as well as development and non-clinical testing of burn resuscitation protocols and algorithms.  相似文献   
59.
60.
Differential susceptibility, a reconceptualization of the diathesis-stress model of psychopathology, describes gene–environment interactions that reflect individual differences in responsiveness to environmental influences, both detrimental and beneficial. This model has been described metaphorically by the classification of orchids, which thrive under optimal care but wither under adverse conditions, and dandelions, which weather broad environmental circumstances but are less responsive to careful cultivation. Etiological research in the field of eating disorders has largely focused on the identification of specific behavioral phenotypes, temperamental traits, genotypes and neurobiological processes that confer risk. In this article, we propose that these putative vulnerability factors represent phenotypes and endophenotypes of a genetic predisposition towards environmental sensitivity. We assert that this sensitivity not only transmits eating disorder risk but also confers resilience, depending on the circumstances. In particular, we propose that differential susceptibility can be used as a framework to organize disparate temperamental and neurobiological findings and their complex interplay with various developmental, environmental and sociocultural influences to increase eating disorder risk and treatment responsiveness. Finally, we assert that viewed through the lens of differential susceptibility, sensitivity can be leveraged to refine our interventions and develop novel treatment and prevention strategies to support favorable outcomes for individuals with eating disorders.  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