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71.
In the present paper, a dynamic plastic damage model for concrete has been employed to estimate responses of a reinforced concrete slab subjected to blast loading. The interaction between the blast wave and the concrete slab is considered in 3D simulation. In the first stage, the initial detonation and blast wave propagation is modelled in 2D simulation before the blast wave reaches the concrete slab, then the results obtained from 2D calculation are remapped to a 3D model. The calculated blast load is compared with that obtained from TM5-1300. Numerical results of the concrete slab response are compared with the explosive test carried out-in the Weapons System Division, Defence Science and Technology Organisation, Department of Defence, Australia.  相似文献   
72.
中老年人由于骨刺形成或椎间盘狭小、椎间孔狭窄等颈椎病引起颈、肩、上肢疼痛、沉重、麻木、瘫痪 ,甚至头痛、眩晕、恶心呕吐等症状。笔者运用体、耳针配合近、远端取穴的针灸治疗方法 ,治疗 96例中老年颈椎病 ,取得满意疗效。现介绍如下 :一、临床资料本组 96例患者中 ,男性  相似文献   
73.
The purpose of this study was to explore the vulnerability for postpartum depression among financially, educationally, and socially advantaged middle-class women (n = 31). Twenty-nine percent reported prenatal depression, 13% reported intimate partner violence, and 22% reported concerns with partner relationships and support expectations after delivery. No illegal substances were reported; however, a past history of smoking and excessive use of caffeine was disclosed. Implications for practice focus on the need to screen and implement intervention programs for these social problems and to adopt measures as a universal standard of care for all women, regardless of demographic advantages.  相似文献   
74.
Do young boys and girls understand what leads to academic success (e.g., talent, effort, good teaching, luck) in the same way? Do young girls and boys have equivalent perceptions of their academic competence? Are these beliefs engendered in the same way across sociocultural contexts? In a cross-cultural study of over 3,000 children in grades 2 to 6, ages 7.2 to 13.6, we discovered that boys and girls around the world have very similar ideas about what generally leads to academic success. Moreover, in the few contexts where boys' and girls' academic performances were equal, their beliefs were also equal. However, when girls outperformed boys, their beliefs in their own talent were no greater than boys' beliefs, even though they did have stronger beliefs than boys in other facets of their achievement potential (e.g., putting forth effort, being lucky, getting their teacher's help). Our findings support the generally close correspondence between children's achievement and their competence-related beliefs, with the exception that young girls appear to specifically discount their talent. The effects held regardless of the children's achievement, intelligence, or age (approximately 8 to 13 years). Girls were more biased in some contexts than in others, however, suggesting that competence-related biases are rooted in culture-specific aspects of school settings.  相似文献   
75.
人才培养目标是各级各类学校依据教育目的的总体要求和不同类型教育的性质任务,对受教育者提出的特定的规格标准。地方高职院校在确立人才培养目标时,哲学层面必须以马克思主义关于人的全面发展学说为指导;心理学层面必须充分认识到人的智能的多元性;教育学层面必须遵循我国社会主义教育的基本价值观和目的观,并在实践中体现高职教育的高等性、职业性、地方性的属性特点。番禺职业技术学院结合自身特点,把人才培养目标定位为培养"一技之长 综合素质"的高技能人才,这一定位充分彰显了番禺职业技术学院的办学特色。  相似文献   
76.
McQueen A  Getz JG  Bray JH 《Child development》2003,74(6):1737-1750
This longitudinal study examined how separation and family conflict mediated the effects of two acculturation variables (English language use and generational status) on substance use (alcohol, tobacco, and marijuana use) and deviant behavior outcomes in a Mexican American high school age sample. Structural equation modeling indicated that separation was a significant mediator of the relationship between acculturation and alcohol use, tobacco use, and deviant behavior. Family conflict mediated the effects of acculturation on marijuana use and deviant behavior. Model comparisons across gender groups suggested that generational status was an influential acculturation measure for females but not males. Additionally, English language use maintained a direct effect on marijuana use among females, whereas this relationship was mediated by separation for males.  相似文献   
77.
We investigated the kinds of instructional and assessment accommodations students with disabilities receive, and the extent to which instructional accommodations match assessment accommodations. Most students who had IEPs in specific content areas received instructional accommodations in those areas, and there were no differences by disability type. We provide data on the specific types of accommodations used. Overall, students' assessment accommodations matched their instructional accommodations, though many students received testing accommodations that had not been received in instruction. Implications are discussed for IEP teams who make decisions about instructional and assessment accommodations.  相似文献   
78.
原子核的秘密的揭露,使人类掌握了新的無穷尽的能源。第一座原子能电站在苏联的建立,为將这个能源实际利用于工業和农業的和平目的,奠定了基础。原子技术的發展,开辟了把放射性同位素应用到各种全然不同的科学技术部門中去的广闊的可能性。人工取得放射性同位素的方法之一,是在原子核反应堆中用中子来照射。比如,用中子照射普通的天然的磷的时候,部分的磷原子核就和中子結合而变成磷的放射性同位素(磷-32)的原子核。当放射性磷的核衰变的时候,核中的一个中子轉化成質子,同时放射出一个β粒子(帶陰电的电子)。衰变是按照这个方式發生  相似文献   
79.
人造元素     
关于化学元素的学说,构成了化学的基本内容,我们周围世界中所有的复杂物质就是由这些元素组成的。在长时期内,人们一直认为元素是不可改变的,并且没有共同的联系。直到1869年,门捷列也夫才发现了所有化学元素的普遍规律性,并且在这个基础上创立了著名的周期系。这位伟大的俄罗斯学者的科学成就,标志着化学上新纪元的开始。门捷列也夫的发现的重要意义是:他确定了所有元素的化学性质随着它们原子量的增加的有规律的周期的重覆性。门捷列也夫把性质相似的元素一个个地上下对齐,这样就组成了周期表。他证明了,每一种化学元素的原子都有着一定的形态,这种形态的特徵不仅仅是由原  相似文献   
80.
信息科学:新的集成观(2)   总被引:1,自引:0,他引:1  
2.1 知识的范围 数据、信息、知识和智慧可以看作是一个连续统一体中的组成部分,它们之中的一个可以引导出另一个,它们之间没有明显的界限。 知识的范围如图1所示。图中,“事件”指发生的一件事、一些条件或社会状态的变化。如果我们想要与这些状态或条件打交道,就必须把它表达出来。我们发明“符号”——数字、字母、雕像或图象作为事件的表达。当我们使用一定规则将这些符号组织起来,就产生了“数据”。我们的数字系统和语言都是这样的表述形式。  相似文献   
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