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《Clinical neurophysiology》2020,131(3):655-664
ObjectiveTo examine whether the occipito-temporal visual N700 component of the event-related potential is sensitive to stimulus probabilities.MethodsP1, N1, P3, and, in particular, the occipito-temporal N700 component of the event-related potential were analysed in response to frequent and rare non-target letters of a continuous performance task in 200 healthy adolescents. Additionally, amplitude habituation with time was examined for the occipito-temporal N700 and N1 components.ResultsThe visual P1, N1, and occipito-temporal N700 components were significantly larger in response to rare letters than to frequent letters, whereas the P3 component demonstrated no amplitude difference. Over time, the occipito-temporal N700 amplitude decreased in response to the rare letters, while the N1 amplitude increased, to both, frequent and rare letters.ConclusionsThis study provides first evidence that the visual occipito-temporal N700 is sensitive to stimulus probabilities, suggesting an enhanced post-processing of rare stimuli in secondary visual areas. The distinct habituation patterns of occipito-temporal N700 and N1 amplitudes distinguish repetition effects on stimulus post-processing (N700) from those on perception (N1).SignificanceThe enhanced N700 component to rare stimuli might reflect an orienting response and underlying attentional processes. The N700 sensitivity to stimulus probabilities should be examined in patient groups with attentional deficits. 相似文献
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《Neuropsychiatrie de l'enfance et de l'adolescence》2020,68(1):29-38
BackgroundAttention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder associated with working memory deficits. In that optic, new interventions designed to train working memory have been developed. Cogmed Working Memory Training (CWMT) is a popular online training program that is said to increase working memory (WM) and related skills in the ADHD population. However, follow-up measures are not systematically included, and long-term effects of CWMT are controversial. Also, the number of studies examining transfer of learning and controlling for medication or comorbidities are limited.ObjectivesThis study investigates the long-term effects of CWMT combined with psychostimulant medication on WM and related skills.MethodsThis study included 31 participants aged 7 to 13 years, diagnosed with ADHD (mixed subtype) associated with learning disorders, oppositional-defiant disorder and/or Tourette syndrome. Participants first completed CWMT and were evaluated at follow-up six months later. We used a randomized, double-blind, placebo-controlled design.ResultsThe results found no significant impact of CWMT at follow-up. There were no improvements of WM nor transfer effects on related skills, academic achievement or ADHD symptoms at six months’ follow-up.ConclusionLong-term efficacy of CWMT is not demonstrated. We can’t support CWMT as an effective complementary treatment for children with ADHD and associated comorbidities. 相似文献
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《Journal of bodywork and movement therapies》2020,24(1):175-181
IntroductionThe ability to direct and maintain attention is a prerequisite for learning. Qigong exercises are already commonly practiced in many developed countries to increase attention and memory. The main goal of this study was to examine whether Qigong would improve the attention levels of adolescents (12–14 years of age) when practiced as part of their physical education course.MethodThree groups of 22 individuals were considered: the verum group, which performed true Qigong; the control group, which performed sham, or placebo Qigong; and the waiting list group. In order to evaluate Qigong effects, attention tests (d2) were applied to all groups before the intervention period (t1) and after two and four weeks of practice (t2 and t3, respectively).ResultsAt t1, there was no significant difference between the verum, control and waiting list groups in all measurable features. After 4 weeks of exercise, the verum group was significantly superior in all measurable features in comparison to the control group and the waiting list group. Values in the waiting list group were generally worse than in the control group (placebo Qigong), but there was no significant difference between the control and waiting list group, showing that the placebo offered an effect that was not significantly greater than the effect of no intervention at all.Conclusion‘White Ball’ Qigong was able to improve attention in adolescents after 4 weeks of practice, leading us to conclude that it may be a useful tool when integrated into physical education classes. 相似文献
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近年来儿童慢性疾病与神经精神疾病的关系及其致病机制已成为儿科领域研究的热点和难点。支气管哮喘(简称哮喘)是儿童期常见的慢性疾病之一,最新基于人群的大样本报道证实哮喘与儿童最常见的神经发育障碍性疾病注意缺陷多动障碍(ADHD)之间关系密切。现就哮喘和ADHD的具体关系及其危险因素最新研究进展进行综述,以期认识二者之间的关系及其危险因素,便于哮喘患儿的长程临床管理。 相似文献
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《Sleep medicine》2021
ObjectivesThe aim of this study was twofold. First, to confirm the deleterious aspect of evening screen exposure in school-aged children, in particular the effect of screens in the bedroom. Second, to explore the three-way association between degree of screen exposure, sleep disturbance, and ADHD symptoms. Solid evidence exists on the link between sleep disturbance and ADHD symptoms, and screen exposure and sleep disturbance. However, no studies have formally assessed the impact of screen exposure on ADHD symptoms in children, as a function of sleep disturbance.MethodsParents of 374 French children (201 girls, 173 boys, mean age of 10.8 ± 2.8 years old) completed the Sleep Disturbance Scale for Children (SDSC), the Attention-Deficit/Hyperactivity Disorder (ADHD) Rating Scale, and a questionnaire about their children's screen habits (total hours in the morning, afternoon, and evening per day). Correlational analyses between evening screen exposure, sleep quality and behavioral problems were conducted. Then, formal mediation analyses were run in order to quantify the relationship between variables.ResultsSchool-aged children with screens in their bedrooms demonstrated more sleep and behavioral problems. Evening TV exposure was associated with higher SDSC and ADHD scores. Furthermore, the Structural Equation Modelling approach confirmed that evening screen exposure is directly associated with more disrupted sleep, which in turn is directly associated with behavioral problems.ConclusionsThese findings encourage families to avoid putting screens in their children's bedrooms, and limit evening screen exposure. They furthermore demonstrate the importance of taking into account screen exposure time (morning, afternoon, evening) and location (bedroom or elsewhere) in future studies. 相似文献
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Ángela M. Ortega-Galán M. Dolores Ruiz-Fernández Rocío Ortiz-Amo José Cabrera-Troya Inés M. Carmona-Rega Olivia Ibáñez-Masero 《Enfermería clínica》2019,29(1):10-17