全文获取类型
收费全文 | 52373篇 |
免费 | 2931篇 |
国内免费 | 162篇 |
专业分类
耳鼻咽喉 | 562篇 |
儿科学 | 1615篇 |
妇产科学 | 1397篇 |
基础医学 | 7391篇 |
口腔科学 | 1609篇 |
临床医学 | 5301篇 |
内科学 | 11064篇 |
皮肤病学 | 1058篇 |
神经病学 | 5004篇 |
特种医学 | 1581篇 |
外科学 | 6201篇 |
综合类 | 277篇 |
现状与发展 | 1篇 |
一般理论 | 20篇 |
预防医学 | 4521篇 |
眼科学 | 900篇 |
药学 | 3749篇 |
中国医学 | 202篇 |
肿瘤学 | 3013篇 |
出版年
2023年 | 477篇 |
2022年 | 603篇 |
2021年 | 1342篇 |
2020年 | 817篇 |
2019年 | 1247篇 |
2018年 | 1774篇 |
2017年 | 1299篇 |
2016年 | 1395篇 |
2015年 | 1526篇 |
2014年 | 1819篇 |
2013年 | 2643篇 |
2012年 | 3979篇 |
2011年 | 4058篇 |
2010年 | 2011篇 |
2009年 | 1699篇 |
2008年 | 3168篇 |
2007年 | 3287篇 |
2006年 | 3153篇 |
2005年 | 3060篇 |
2004年 | 2849篇 |
2003年 | 2720篇 |
2002年 | 2526篇 |
2001年 | 869篇 |
2000年 | 891篇 |
1999年 | 718篇 |
1998年 | 316篇 |
1997年 | 251篇 |
1996年 | 258篇 |
1995年 | 208篇 |
1994年 | 187篇 |
1993年 | 158篇 |
1992年 | 359篇 |
1991年 | 321篇 |
1990年 | 277篇 |
1989年 | 277篇 |
1988年 | 215篇 |
1987年 | 252篇 |
1986年 | 237篇 |
1985年 | 223篇 |
1984年 | 171篇 |
1983年 | 133篇 |
1982年 | 116篇 |
1981年 | 113篇 |
1980年 | 86篇 |
1979年 | 139篇 |
1978年 | 88篇 |
1977年 | 100篇 |
1976年 | 74篇 |
1975年 | 92篇 |
1974年 | 99篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
Adilson Cunha Ferreira Edward Araujo Júnior Wellington P. Martins João Francisco Jordão Antônio Hélio Oliani Simon E. Meagher 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1706-1710
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality. 相似文献
3.
4.
5.
6.
Raphaëlle Jouin Denis Chateaux Dominique Drapier Thierry Pham Hoang 《Annales médico-psychologiques》2019,177(9):902-910
Klinefelter syndrome (KS) (47,XXY) is the most common aneuploidy (1/650) of sexual chromosome among male (0,1 à 0,2 % of male population) (Hong and Reiss, 2014). Because its large physical phenotypic variability (high tall, sparse hairiness, gynecomastia), this syndrome is largely underdiagnosed (less than 25 % of affected persons) (Samango-Sprouse et al., 2018). Nevertheless, cognitive variability is smaller. Normal to low average total IQ, low verbal IQ, social problems and high levels of psychiatric comorbidities including early aggressiveness are commonly described (Hong and Reiss, 2014). In Denmark, higher risks of committing sexual crime and arson (compared to criminal controls) was recently reported (Stochholm et al., 2012). Quite a few clinically relevant cases reports scattered in the literature, suggests the presence of a pattern of a specific subtype of KS inpatients among forensic population (Bénézech, 1975). However, very few studies provide quantitative or qualitative pertaining to robust results. KS well-documented neurobiological (van Rijn, 2018) (e.g. low levels of testosterone), neuropsychological (Bénézech, 1975; Hong and Reiss, 2014; Samango-Sprouse et al., 2018; Savic, 2012; Seara-Cardoso et al., 2016; Senon, 2005; Stochholm et al., 2012; van Rijn, 2018; van Rijn et al., 2008; van Rijn et al., 2018; van Rijn et al., 2014; van Rijn et al., 2012) [29] (e.g. alterations of both complex cerebral — attention, empathy — and behavioral regulation functions - inhibition, mental flexibility, emotional response modulation, control of own actions) and neuroanatomical (Hong and Reiss, 2014; Itti et al., 2003; Savic, 2012; van Rijn et al., 2008; van Rijn et al., 2012) [29] (e.g. limbic system and temporal lobe abnormal volume, hemispheric specialization shortcoming) features may be helpful to understand comorbid symptoms psychopathology. Numbers of recent studies conduct on KS pediatric or adult population provide interesting results on conduct, anxiety, psychotic and autism spectrum disorders. In addition, some authors use genetic and epigenetic specific features of sex chromosome aneuploidies (e.g. X genes neurodevelopmental role; imprinting) in order to clarify genotype-phenotype links of comorbid symptoms (Bruining et al., 2011; Zitzmann et al., 2004;). With Belgian colleagues from the Social Defense Research Center (CRDS, Tournai, Belgium), we are currently recruiting KS inpatients from security hospitals or psychiatric units in Belgium and France. We aim to assess psychopathic traits with the Psychopathy Checklist Revised (PCL-R, Hare) (Hare, 2003). Our first results concerning 3 KS males outline that PCL-R is useful for the characterization of clinical phenotype among KS forensic sample. While three of them present psychopathic traits, two of them present categorical double diagnose “psychopathy-KS” (total PCL-R score > = 30/40 (Delannoy et al., 2017)). Moreover, dimensional analysis support our hypothesis of a higher prevalence of “explosive profile” in comparison to other psychopathic profiles in our sample (Delannoy et al., 2017). The present article summarizes historic background (e.g. “psychopathy” disappearance of mental disorder reference classification schemes, “crime chromosome” (Bénézech, 1975)) and current context argues (e.g. French psychiatrists court experts widely refer to psychopathy concept despite a lack of consensual definition (Senon, 2005), weak knowledge and training of PCL-R and its related biopsychological recent findings (Blair, 2013; de Oliveira-Souza et al., 2008; Dotterer et al., 2017; Glenn and Raine, 2014; Hosking et al., 2017; Korponay et al., 2017; Pham, 1995; Pham, 2005; Raine, 2008; Raine et al., 2003); stigma and discrimination apprehensions of KS and psychopath) that motivate our research project. Finally, we discuss the advantages of our research protocol on KS participants assessed with PCL-R, such as tackling stigma and discrimination, better understanding psychopathology, and clarifying murky interactions of biological, psychological and social factors entangled in the development of these two fascinating troubles. 相似文献
7.
8.
9.
10.
Lars J Vatten Tom I L Nilsen P?l R Romundstad Wenche B Dr?yvold Jostein Holmen 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):909-915
OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men. 相似文献