全文获取类型
收费全文 | 9579篇 |
免费 | 813篇 |
国内免费 | 160篇 |
专业分类
耳鼻咽喉 | 135篇 |
儿科学 | 221篇 |
妇产科学 | 144篇 |
基础医学 | 1027篇 |
口腔科学 | 259篇 |
临床医学 | 1059篇 |
内科学 | 1540篇 |
皮肤病学 | 117篇 |
神经病学 | 1392篇 |
特种医学 | 206篇 |
外科学 | 720篇 |
综合类 | 548篇 |
一般理论 | 6篇 |
预防医学 | 1698篇 |
眼科学 | 140篇 |
药学 | 918篇 |
1篇 | |
中国医学 | 163篇 |
肿瘤学 | 258篇 |
出版年
2024年 | 19篇 |
2023年 | 219篇 |
2022年 | 205篇 |
2021年 | 460篇 |
2020年 | 455篇 |
2019年 | 503篇 |
2018年 | 443篇 |
2017年 | 416篇 |
2016年 | 393篇 |
2015年 | 325篇 |
2014年 | 505篇 |
2013年 | 1082篇 |
2012年 | 413篇 |
2011年 | 415篇 |
2010年 | 357篇 |
2009年 | 386篇 |
2008年 | 403篇 |
2007年 | 393篇 |
2006年 | 378篇 |
2005年 | 320篇 |
2004年 | 292篇 |
2003年 | 274篇 |
2002年 | 233篇 |
2001年 | 184篇 |
2000年 | 147篇 |
1999年 | 141篇 |
1998年 | 128篇 |
1997年 | 112篇 |
1996年 | 103篇 |
1995年 | 107篇 |
1994年 | 69篇 |
1993年 | 72篇 |
1992年 | 77篇 |
1991年 | 69篇 |
1990年 | 55篇 |
1989年 | 53篇 |
1988年 | 37篇 |
1987年 | 30篇 |
1986年 | 30篇 |
1985年 | 39篇 |
1984年 | 35篇 |
1983年 | 19篇 |
1982年 | 27篇 |
1981年 | 35篇 |
1980年 | 21篇 |
1979年 | 16篇 |
1977年 | 14篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1974年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
993.
994.
Mizia-Stec K Gasior Z Mizia M Haberka M Holecki M Zwolińska W Katarzyna K Skowerski M 《Echocardiography (Mount Kisco, N.Y.)》2007,24(10):1051-1057
BACKGROUND: The risk of atherosclerosis and its complications differs between male and female subjects. This is probably associated with gender differences in endothelial function as reflected by endothelium-dependent vasodilation. The aim of the study was to compare flow-mediated dilatation (FMD) in males and females with coronary artery disease (CAD), and to determine factors that might potentially influence FMD. METHODS: Ninety-six patients with stable CAD (CCS II-III): 76 males (mean age: 57.7 +/- 10 years) and 20 postmenopausal females (mean age: 60.1 +/- 10 years) were included into the study. Clinical data, pharmacotherapy, concomitant diseases, and FMD were all assessed. FMD was measured with high-resolution ultrasound as the percent change of brachial artery diameter (BAd) after a 3-minute occlusion (%FMD), and following the administration of 0.4 mg sublingual nitroglycerin (%NTG-MD). RESULTS: The percentage of FMD was significantly decreased (P < 0.05), and BAd was significantly larger (P < 0.001) in males as compared to females. Clinical data, pharmacotherapy, and concomitant diseases were comparable in the study groups.In all subjects examined, %FMD was related to BAd (r =-0.415, P < 0.001) and the percentage of ejection fraction (EF%) (r = 0.325, P < 0.01) in the univariate analysis, and to BAd only (r =-0.343, P < 0.01) in the multivariate analysis. The percentage of nitroglycerine-mediated vasodilatation (NTG-MD) correlated negatively with BAd (r =-0.430, P < 0.001), and positively with EF% (r = 0.334, P < 0.01) in the univariate analysis, and with BAd (r =-0.288, P < 0.05) in the multivariate analysis. Index %FMD x BAd was comparable for male and female subjects. CONCLUSIONS: Males and postmenopausal females with CAD show differences in endothelium-dependent vasodilatation that seem to secondarily result from differences in the BAd. Objective comparison of %FMD is only possible between patients with the same brachial artery size. 相似文献
995.
Gromadzka G Baranska-Gieruszczak M Sarzynska-Dlugosz I Ciesielska A Czlonkowska A 《Acta neurologica Scandinavica》2007,116(6):392-398
OBJECTIVE: In human genetic studies an effect of the apolipoprotein E gene (APOE) polymorphism on the risk, course and prognosis in chronic and acute nervous system disorders was established. We aimed to evaluate whether the APOE genotype is related to acute neurological impairments due to ischemic stroke (IS), and to outcomes (up to 1 year) indicated by severe functional disability, dependence in daily living or death. MATERIALS AND METHODS: A total of 657 patients (326 men, 331 women), divided into the three groups: E2 (APOEepsilon2/epsilon3 subjects), E3 (APOEepsilon3/epsilon3 subjects), and E4 (APOEepsilon3/epsilon4 and epsilon4/epsilon4 subjects), were analyzed. RESULTS: There was no association between the APOE genotype and baseline clinical characteristics, severity of neurological impairments during acute stroke, and 1-year outcome, when analyzing whole patient population. APOE gene interacted with gender in predicting severity of acute neurological deficit and post-stroke mortality within the period up to 1 year after the IS. Gender-stratified analysis indicated the E4 genotype as a significant independent positive predictor of death within 1 year after stroke incidence in men patients. CONCLUSION: Ischemic stroke severity and outcome may be affected by complex interactions between gender and genetic factors that warrant further exploration. 相似文献
996.
OBJECTIVE: To evaluate the integrity of the blood-brain barrier (BBB) in incident Alzheimer's disease (AD). MATERIALS AND METHODS: The mean age of the 157 patients (45% men) was 69.7(9.4) years (range 51-88 years). The patients had undergone a thorough investigation including magnetic resonance imaging or computed tomography of the brain. The cerebrospinal(CSF)/plasma albumin ratio (albumin ratio) was used as a measure of BBB function. RESULTS: There were gender differences with respect to albumin ratio and plasma creatinine with higher values in men (P < 0.001). 42% of the men and 13% of the women (P < 0.001) had a mild to moderate BBB dysfunction when applying the reference limit of the laboratory (<9.2). Both male gender (P = 0.002) and plasma creatinine (P = 0.009) were independently associated with the albumin ratio when controlling for putative confounders. CONCLUSIONS: The BBB is dysfunctional in a portion of patients with AD, both women and, primarily, men. The dysfunction might influence the clearance of both harmful and beneficial substances across the barrier. Renal function might have an impact on the BBB. 相似文献
997.
Vaskinn A Sundet K Friis S Simonsen C Birkenaes AB Engh JA Jónsdóttir H Ringen PA Opjordsmoen S Andreassen OA 《Acta psychiatrica Scandinavica》2007,116(4):263-270
OBJECTIVE: Impaired emotion perception is documented for schizophrenia, but findings have been mixed for bipolar disorder. In healthy samples females perform better than males. This study compared emotion perception in schizophrenia and bipolar disorder and investigated the effects of gender. METHOD: Visual (facial pictures) and auditory (sentences) emotional stimuli were presented for identification and discrimination in groups of participants with schizophrenia, bipolar disorder and healthy controls. RESULTS: Visual emotion perception was unimpaired in both clinical groups, but the schizophrenia sample showed reduced auditory emotion perception. Healthy males and male schizophrenia subjects performed worse than their female counterparts, whereas there were no gender differences within the bipolar group. CONCLUSION: A disease-specific auditory emotion processing deficit was confirmed in schizophrenia, especially for males. Participants with bipolar disorder performed unimpaired. 相似文献
998.
It is a relatively uncommon event that children find themselves in a situation with a parent who undergoes a transition from
one sex to another. Unlike situations of divorce or a parent with a medical or major psychiatric disorder, it is unlikely
that the children will know of other children who encounter similar situations. There is very little literature that describes
the adjustment of these children and the nature of their relationships with their parents and peers. Such information would
be beneficial for clinicians assisting children and families in this situation. To better delineate the adjustment of these
children, we interviewed 27 parents of 55 children. The interview took place on average 6 years after the gender transition.
The measures obtained included the parent and child relationships at present and also at the time of the transition. We also
inquired about academic function, peer relationships and social stigma. The results found that children who were younger at
the time of the parent’s transition tended to have better relationships and less adjustment difficulties. In addition, parental
conflict that continues after the transition period tends to reflect greater family conflict between the transitioned parent
and their child. 相似文献
999.
Wallien MS van Goozen SH Cohen-Kettenis PT 《European child & adolescent psychiatry》2007,16(5):309-315
Background Internalizing psychopathology, anxiety in particular, is assumed to contribute to the development of gender Identity disorder
(GID). Until now, anxiety has only been reported in studies using parent-report questionnaires; physiological correlates of
anxiety have not been studied. In this study we assessed anxiety and stress in children with GID by measuring their cortisol,
heart rate (HR) and skin conductance levels (SCL) and asking them to repeat their moods and experience of control.
Methods By using an established psychological challenge, involving provocation and frustration, we investigated whether children with
GID as compared to healthy controls react in a more anxious way under these experimental circumstances. We assessed anxiety
levels in 25 children with GID and 25 matched controls by measuring cortisol, HR and skin conductance and examined whether
a pattern of increased physiological activity corresponded with the feeling of being less in control and having more intense
negative emotions.
Results The results showed that children with GID had more negative emotions and a tonically elevated SCL. There were no differences
between the groups in cortisol and HR.
Conclusion This is the first study that shows that children with GID have a more anxious nature as compared to their normal counterparts. 相似文献
1000.
Functional MRI was used to identify the brain areas underlying automatic beliefs about gender and race, and suppression of those attitudes. Participants (n = 20; 7 females) were scanned at 3 tesla while performing the Implicit Association Test (IAT), an indirect measure of race and gender bias. We hypothesized that ventromedial prefrontal cortex areas (PFC) would mediate gender and racial stereotypic attitudes, and suppression of these beliefs would recruit dorsolateral prefrontal cortex (DLPFC) and the anterior cingulate cortex (ACC). Performance data on the IAT revealed gender and racial biases. Racial bias was correlated with an explicit measure of racism. Results showed activation of anteromedial PFC and rostral ACC while participants implicitly made associations consistent with gender and racial biases. In contrast, associations incongruent with stereotypes recruited DLPFC. Implicit gender bias was correlated with amygdala activation during stereotypic conditions. Results suggest there are dissociable roles for anteromedial and dorsolateral PFC circuits in the activation and inhibition of stereotypic attitudes. 相似文献