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41.
It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60-77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations.  相似文献   
42.
The present study had two aims: First, to investigate the joint and specific roles of working memory (WM) and intelligence as predictors of school achievement. And second, to replicate and extend earlier findings (Spinath, Spinath, Harlaar, & Plomin, 2006) on the incremental validity of non-cognitive over cognitive abilities in the prediction of school achievement. The present sample consisted of N = 179 Chinese primary school children in the fourth grade. All measures including working memory (WM), intelligence and motivational items were assessed in class. Teachers provided test scores for the domains of Chinese and Math. We found that WM was a good predictor of school achievement and comparable in predictive power to intelligence. Together, cognitive ability including both WM and intelligence explained 17.8% and 36.4% of the variance in children's Chinese and Math scores, respectively. The relative importance of WM and intelligence varied with school domains with greater predictive power of WM for Math while intelligence explained a greater proportion of the variance in Chinese although the magnitude of this difference was only moderate. Domain-specific motivational constructs contributed only marginally to the prediction of school achievement for both Chinese and Math.  相似文献   
43.
校园欺凌现象在全球范围普遍存在,为有效解决校园欺凌问题,研究一采用《特拉华校园受欺凌量表》、《简易应对方式量表》以及《社会情绪健康量表》对416名5~6年级小学生进行了调查,结果发现,小学生消极应对方式可以显著预测校园受欺凌,社会情绪能力在消极应对方式与校园受欺凌中起调节作用。此基础上,研究二开展基于社会情绪能力的校园受欺凌团体辅导干预研究。结果表明,社会情绪能力的提升可以显著降低校园受欺凌水平。  相似文献   
44.
Given the prevalence of imagery appeals in today’s marketplace, the current research studies the role of mental imagery in how consumers process and react to advertisements with different numbers of ad claims. Past research has proposed “three” as the magical number of ad claims that maximizes persuasion, with more than three ad claims increasing skepticism and reducing evaluation. In the current research, we replicate this so-called “charm of three” effect, but only when consumers do not engage in mental imagery; when they do, however, we find that the effect is moderated, in that more ad claims beyond three produces more favorable product evaluation. Additionally, we provide evidence that the moderating effect of mental imagery is driven by transportation and skepticism toward the ad claims, with mental imagery increasing transportation and decreasing skepticism when there are more than three ad claims. Our research contributes to a better understanding of the “charm of three” effect, its boundary conditions, and underlying mechanism.  相似文献   
45.
In the family‐based prevention science literature, family functioning, defined as positive parenting, parental involvement, family cohesion, family communication, parental monitoring of peers, and parent–adolescent communication, has been shown to ameliorate HIV risk behaviors in Hispanic youth. However, the majority of studies have relied solely on parent or adolescent reports and we know very little about parent–adolescent family functioning discrepancies. Therefore, the purpose of this study was to examine whether and to what extent parent–adolescent discrepancies in family functioning increased the risk of HIV risk behaviors, including substance use and sexual risk behaviors, and whether these associations vary as a function of acculturation and youth gender. A total of 746 Hispanic 8th grade youth and their primary caregivers were included in the study. Structural equation modeling findings indicate that parent–adolescent family functioning discrepancies are associated with an increased risk of Hispanic adolescent HIV risk behaviors, including lifetime and past 90‐day alcohol and illicit drug use, and early sex initiation. In addition, study findings indicate that results vary by acculturation and youth gender. Findings are discussed in the context of existing family‐based research and practice in preventing and reducing HIV risk behaviors among Hispanic youth and their families.  相似文献   
46.
随着人们对于肿瘤性疾病的发生、发展、转移机制的进一步探索,循环肿瘤细胞(CTCs)逐渐进入人们视野,其应用价值日益体现,可用于肿瘤性疾病的早期诊断及治疗效果的监测,尤其是对于早期肿瘤的诊断具有独特优势。其富集技术及检测方法也在发生着日新月异的变化。近年来,微流控分析芯片技术运用于 CTCs 的富集及检测,具有高丰度、高富集度、高活性及不需要对样本进行预处理等优点使得人们聚焦于此技术,本文对微流控分析芯片在 CTCs 检测中的运用做简要综述。  相似文献   
47.
目前肝衰竭发病率和病死率仍然较高,肝衰竭成为威胁患者生命的严重疾病。基于肝脏具有强大再生能力,人工肝支持系统作为一种“过渡”措施,为肝衰竭患者的肝功能恢复赢得时间。人工肝支持系统根据性质不同分为非生物型人工肝、生物型人工肝和混合型人工肝。目前非生物型人工肝已在肝病治疗领域被广泛应用,但生物型及混合型人工肝的临床应用还存在很多问题需要进一步研究和解决。因此本文对人工肝的作用、临床应用现状、存在问题及研究进展进行综述。  相似文献   
48.
以大学生为被试,探讨自我损耗、情绪动机对冲动决策的影响。采用2×2×2的混合实验设计,组内变量为自我损耗,组间变量为情绪动机方向和强度,使用双任务范式操作自我损耗,使用情绪动机图片启动被试的情绪动机,使用延迟折扣任务的指标k值测量冲动决策。结果发现,高趋近动机的k值大于低趋近动机,高回避动机的k值大于低回避动机。结果表明,自我损耗、情绪动机对冲动决策有明显影响。  相似文献   
49.
The study assessed 30-month-old Mandarin-speaking children’s awareness of aspectual distinctions involving the perfective marker le and the imperfective marker zhe in a preferential looking experiment. In the experiment, we presented our child subjects with a choice between two video clips (one depicting a closed event and the other depicting an on-going event), in the presence of an auditory stimulus (either the le sentence, the zhe sentence or the control sentence without any aspect marker). Children’s looking behavior in the task was recorded and analyzed. The results revealed 30-month-old children’s emerging sensitivity to the aspectual contrast between le and zhe. This was manifest by an increase in looking to the closed event when hearing the le sentence and an increase in looking to the on-going event when hearing the zhe sentence. The absence of le or zhe in the control sentence did not result in any increase or decrease in looking to either event. We also found that the effect of le on children’s looking behavior was immediate whereas the effect of zhe was late. We attributed this difference to the facilitative role of le in children’s sentence processing as well as their preference for the event boundary. The results lend support to the continuity view that functional morphemes like aspect markers are available to children early in language development.  相似文献   
50.
采用中学生心理健康诊断量表(MHT)对湖南省1292名留守儿童的焦虑情绪进行施测,并用潜在剖面分析方法探究留守儿童的焦虑情绪问题是否存在异质性,以及留守儿童相关的人口学因素对焦虑情绪异质性的作用机制。结果发现,留守儿童的焦虑情绪存在明显的异质性,可以分为三种潜在类别:“严重焦虑情绪型”、“中等程度焦虑情绪型”和“低焦虑情绪型”;留守男生、小学五年级、高中二年级、留守时间越长、留守初始年龄越小的留守儿童更容易焦虑情绪严重;无论是父亲外出、母亲外出还是双亲外出对留守儿童的焦虑情绪严重性的影响是一致的。由此,应根据留守儿童的性别、年级、留守时长和留守的初始年龄等情况特点,开展针对性的预防和干预措施,缓解留守儿童焦虑。  相似文献   
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