全文获取类型
收费全文 | 22825篇 |
免费 | 261篇 |
国内免费 | 718篇 |
专业分类
23804篇 |
出版年
2024年 | 10篇 |
2023年 | 29篇 |
2022年 | 54篇 |
2021年 | 91篇 |
2020年 | 104篇 |
2019年 | 80篇 |
2018年 | 3551篇 |
2017年 | 2898篇 |
2016年 | 2303篇 |
2015年 | 268篇 |
2014年 | 142篇 |
2013年 | 287篇 |
2012年 | 717篇 |
2011年 | 2589篇 |
2010年 | 2689篇 |
2009年 | 1653篇 |
2008年 | 1896篇 |
2007年 | 2457篇 |
2006年 | 297篇 |
2005年 | 450篇 |
2004年 | 319篇 |
2003年 | 224篇 |
2002年 | 129篇 |
2001年 | 85篇 |
2000年 | 93篇 |
1999年 | 75篇 |
1998年 | 53篇 |
1997年 | 48篇 |
1996年 | 33篇 |
1995年 | 27篇 |
1994年 | 19篇 |
1993年 | 22篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 16篇 |
1989年 | 9篇 |
1988年 | 9篇 |
1987年 | 4篇 |
1986年 | 11篇 |
1985年 | 8篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1976年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
Swaisgood RR White AM Zhou X Zhang G Lindburg DG 《Journal of comparative psychology (Washington, D.C. : 1983)》2005,119(3):325-334
This study investigated the responses of 14 giant pandas (Ailuropoda melanoleuca) to 5 enrichment items (3 manipulable objects, 2 feeding devices) that possess different properties affording varying behavioral opportunities. Enrichment items were quantitatively described by using 12 properties. Pandas displayed no preferences among the 5 enrichment treatments, all of which had similar positive effects on behavioral measures of well-being (behavioral diversity, stereotypy). However, each item promoted a distinct behavioral profile, readily mapped onto the enrichment's properties. These results suggest that it may be important to stimulate behavioral diversity but that specific behaviors or enrichment properties are not required. The unique behavioral topography seen with these enrichments also suggests that providing multiple enrichments with varying properties will maximize overall behavioral diversity. 相似文献
132.
中国西南少数民族与道教神仙信仰 总被引:2,自引:0,他引:2
随秦汉以来中华民族多元一体格局的形成,道教逐渐传播进入西南少数民族地区.本文通过西南少数民族地区神仙信仰典型事例的论析,说明道教与西南少数民族文化的相互融摄,构成了具有地域特色的中国传统文化. 相似文献
133.
Wigal SB McGough JJ McCracken JT Biederman J Spencer TJ Posner KL Wigal TL Kollins SH Clark TM Mays DA Zhang Y Tulloch SJ 《Journal of attention disorders》2005,9(1):275-289
Mixed amphetamine salts extended release (MAS XR; Adderall XR) and atomoxetine (Strattera) were compared in children 6 to 12 years old with attention deficit/hyperactivity disorder (ADHD) combined or hyperactive/impulsive type in a randomized, double-blind, multicenter, parallel-group, forced-dose-escalation laboratory school study. Primary efficacy measure was the SKAMP (Swanson, Kotkin, Agler, M-Flynn, and Pelham) behavioral rating scale. Changes in mean SKAMP deportment scores from baseline were significantly greater for MAS XR (n = 102) than for atomoxetine (n = 101) overall (-0.56 and -0.13, respectively; p < .0001) and at each week (p < .001). Adverse events were similar for both treatment groups. The extended time course of action and greater therapeutic efficacy of MAS XR suggests that it is more effective than atomoxetine in children with ADHD. 相似文献
134.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution. 相似文献
135.
Catalano GD 《Science and engineering ethics》2004,10(2):409-415
A senior level capstone design experience has been developed and offered with a particular emphasis on many of the professional
issues raised in Accreditation Board for Engineering and Technology (ABET) Engineering Criterion IV. The course has sought
to develop student awareness of the ethical foundation of the engineering profession, the global and societal framework within
which engineers practice, and the environmental impact on engineering. The capstone design course also focused upon improving
the technical communications skills of the graduating senior class with both extensive instruction in writing and multiple
workshops dealing with the art of making an effective oral presentation. The effectiveness of the design course was assessed
using Kirkpatrick’s model for evaluating training programs.
An earlier version of this paper was presented at the “Ethics and Social Responsibility in Engineering and Technology” meeting,
New Orleans, 2003. 相似文献
136.
Brook JS Adams RE Balka EB Whiteman M Zhang C Sugerman R 《The Journal of genetic psychology》2004,165(2):203-220
The authors assessed whether (a) early illicit drug use predicted later risky sexual activity, (b) early risky sex predicted later illicit drug use, and (c) common factors affected both risky sexual behavior and illicit drug use. African American and Puerto Rican youth completed questionnaires in their classrooms at Time 1 (T1) and face-to-face interviews with the authors in their homes 5 years later at Time 2 (T2). Logistic regression analyses showed the association between T1 illicit drug use and T2 risky sexual activity and between T1 risky sexual behavior and T2 illicit drug use. With few exceptions, T1 illicit drug use was associated with all of the T2 risky sexual behaviors. After controlling for demographic factors, the authors found that multiple sex partners at T1 was not related to illicit drug use at T2. Condom use at T1 was related to illicit drug use at T2, whereas sexually transmitted diseases and adolescent pregnancy were not related to this drug use. The findings indicated that assessments of and treatments for substance use should focus on the risky sexual behaviors that seem to accompany illicit drug use. 相似文献
137.
Faculty members at Canadian business schools were surveyed regarding their ethical perceptions of behaviours related to undergraduate instruction. Fifty-five behavioural statements were listed and respondents were asked to rate the extent to which they felt each behaviour was ethical or unethical. The only item that respondents endorsed as unequivocally unethical (90% indicated it was definitely unethical) was Becoming sexually involved with an undergraduate in one of your classes. We also compared the results of our sample to those of an American sample. Overall, an interesting pattern of differences emerged between the responses obtained in Canada and the U.S. In general, the direction of the significant differences was such that Canadian professors viewed the behaviours in question as less ethical than did their American counterparts. 相似文献
138.
Caring for a family member with dementia is generally regarded as a chronically stressful process, with potentially negative physical health consequences. However, no quantitative analysis has been conducted on this literature. The authors combined the results of 23 studies to compare the physical health of caregivers with demographically similar noncaregivers. When examined across 11 health categories, caregivers exhibited a slightly greater risk for health problems than did noncaregivers. However, sex and the health category assessed moderated this relationship. Stronger relationships occurred with stress hormones, antibodies, and global reported health. The authors argue that a theoretical model is needed that relates caregiver stressors to illness and proffers moderating roles for vulnerabilities and resources and mediating roles for psychosocial distress and health behaviors. 相似文献
139.
Zhang LF 《The Journal of psychology》2003,137(6):517-544
The main purpose of the author's research was to investigate whether thinking styles significantly contribute to critical thinking dispositions. Two samples of Chinese university students, one from Beijing and the other from Nanjing, participated in the study. The participants responded to the Thinking Styles Inventory (R. J. Sternberg & R. K. Wagner, 1992) based on Sternberg's theory of mental self-government and to the California Critical Thinking Disposition Inventory (P. Facione & N. Facione, 1992), which assessed the 7 dimensions of the critical thinking construct as defined in The Delphi Report (see P. Facione, N. Facione, & C. Giancarlo, 2001). Results from both samples supported the prediction that thinking styles statistically contribute to individual differences in critical thinking dispositions. These findings have implications not only for classroom instruction and assessment but also for academic and nonacademic program development. 相似文献
140.
Subjects were instructed to match 3-dimensional forms while event-related potentials (ERPs) were recorded to explore the relationship between visual completion and conflict processing. Sequentially presented paired stimuli (S1 and S2) were identical in condition I, while in condition II the images were of the same contour, but S2 contained an invisible portion, and in condition III S1 and S2 were of different contours. Subjects indicated if stimuli were physically identical or contour similar in two separate sessions. Following the onset of S2, ERP components P100, N150, and LPC were recorded in all conditions. N150 was enhanced in condition II in both sessions, and N270 was elicited in conditions II and III. N150 is related to visual completion, while N270 is related to the evaluation of information discrepancy, belonging to independent systems. 相似文献