首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   38043篇
  免费   751篇
  国内免费   3篇
  38797篇
  2019年   462篇
  2018年   619篇
  2017年   604篇
  2016年   677篇
  2015年   494篇
  2014年   609篇
  2013年   2978篇
  2012年   1036篇
  2011年   1109篇
  2010年   673篇
  2009年   667篇
  2008年   882篇
  2007年   971篇
  2006年   874篇
  2005年   789篇
  2004年   779篇
  2003年   742篇
  2002年   759篇
  2001年   1149篇
  2000年   1186篇
  1999年   848篇
  1998年   415篇
  1997年   352篇
  1996年   381篇
  1995年   355篇
  1992年   705篇
  1991年   707篇
  1990年   696篇
  1989年   651篇
  1988年   665篇
  1987年   591篇
  1986年   615篇
  1985年   630篇
  1984年   489篇
  1983年   474篇
  1982年   356篇
  1981年   347篇
  1979年   586篇
  1978年   467篇
  1977年   354篇
  1975年   482篇
  1974年   593篇
  1973年   619篇
  1972年   498篇
  1971年   488篇
  1970年   436篇
  1969年   437篇
  1968年   585篇
  1967年   533篇
  1966年   479篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
161.
Starting with the premise that research questions emanating from the fields of psychoneuroimmunology and behavioral medicine may provide critical information for understanding and treating acquired immune deficiency syndrome (AIDS), we provide brief backgrounds on psychoneuroimmunology and on AIDS. Previously, Solomon had generated 25 hypotheses based on the thesis that the immune and central nervous systems are intimately linked. Eight hypotheses from his list are presented as particularly relevant to AIDS. From these hypotheses, we derived a set of 12 new questions to be addressed in research on AIDS. Evidence and illustrations from studies in the literature, from our own research on psychoimmunologic relationships and psychosocial factors related to outcome, and from clinical examples is discussed for each question. Finally, suggestions are offered to address some of the problems in conducting psychoneurologic research.  相似文献   
162.
A perceptual reinforcement theory of stereotyped movements is advanced by Lovaas, Newsom, and Hickman (1987) in an effort to integrate a number of diverse observations about the origins and maintenance of this behavior. We, in turn, argue that the theory, as presented, is logically flawed and fails to take into account important biological findings and theory concerning pathological stereotyped acts. An alternative theory, derived primarily from neurological concepts, is briefly described.  相似文献   
163.
164.
165.
In the first ( N = 140) of two quasi-experimental field studies, trial group employees were changed from a 5/40 to a 4/40 work schedule for four months then returned to a 5/40 schedule. In a second study ( N = 102), trial group employees were changed from 5/40 to flextime. Reactions were evaluated using a model for understanding the impact of work schedules. The effects of schedule changes matched those anticipated by pre-intervention surveys of employees. Factors related to organizational effectiveness were enhanced where specific organizational needs were met. Interference with personal activities was reduced where employees had experienced specific difficulties. The most powerful effect, however, was on worker attitudes toward specific work schedules. In addition, a mild positive (perhaps Hawthorne) effect was evident for a wide range of general worker reactions.  相似文献   
166.
The functional development of cardiac and adrenal medullary responses to reflex activation of the sympathetic nervous system was studied in preweanling spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive rats. Pups of the two strains received injections of insulin or saline at 2, 4, 8, 12, or 16 days of age and were sacrificed 3 h later. Insulin administration produces a significant decrease in circulating levels of glucose which in turn results in a centrally mediated increase in sympathetic outflow. The induction of ornithine decarboxylase (ODC) in heart and the depletion of epinephrine from the adrenal medulla served as tissue markers of functional sympathetic neurotransmission. WKY and SHR pups had comparable levels of ODC activity in heart under basal conditions. In contrast, levels of catecholamines in the adrenals were greater in SHR pups at 2 and 4 days of age. Following insulin administration, SHR pups exhibited a greater induction of cardiac ODC activity at 2, 4, and 8 days of age compared to age-matched WKY controls. However, there were no differences between SHR and WKY pups in the magnitude of the adrenal medullary response to insulin-induced hypoglycemia. These alterations in sympathetic-target tissue development during the first postnatal week of life may contribute in part to the higher arterial pressures maintained by SHRs throughout the lifespan.  相似文献   
167.
The influence of sexual experience on preference behavior was investigated in adult female rats. In the first experiment, preference behavior for sexually active males versus estrous females was investigated in female rats who were experienced with mounting behavior. Preference of these mount experienced females was compared to preference of females who were naive in this respect. Mount experience with estrous females induced a female-directed preference in ovariectomized female rats, irrespective of whether the females were treated with OIL or with testosterone-propionate (500 micrograms TP, injected once 48 h prior to testing). Sexually naive, OIL-treated females did not show a preference for males or females, but TP induced a preference for a male. Individual differences in mount frequency were not correlated with preference behavior. In the second experiment, the influence of experience with feminine sexual responses on preference behavior was investigated. OIL-treated and TP-treated females oriented equally toward males and females when they had been given the opportunity to copulate with males prior to the preference tests. The results strongly suggest that prior sexual experience is an important determinant of preference behavior. The female's behavior during sexual interactions was, however, not predictive of later preference.  相似文献   
168.
This psychophysiological evaluation of an aerobic exercise program examined specifically whether aerobic training modified Pattern A for those individuals at behavioral risk for developing coronary heart disease, i.e., young Type A individuals. At pretest and posttest of this secondary prevention study, Type A and Type B subjects were assessed in three conditions: aerobic exercise program, nonaerobic activity (Aikido, a martial art) control, and notreatment control. After 10 weeks, Type A but not Type B subjects exhibited lower Pattern A behavior in the aerobic program than in control conditions. Average workout pulse rates and differentially reliable increases in aerobic capacity indicated that aerobic training was indeed aerobic, whereas aikido activity was not. Even though selected nonaerobic factors, such as locus of control and group participation, did not mediate the Pattern A decrease for Type A's when comparing aikido and aerobic conditions, changes in aerobic capacity may have been the mediator. Generalizability of the results and implications for theoretical development and clinical intervention are discussed.  相似文献   
169.
From an initial pool of 96 students, 36 subjects were selected based on Novaco Anger Scale scores to form high-, moderate-, and low-anger groups (n=12). They completed self-report questionnaires and participated in a structured interview designed to elicit cognitive and affective responses to hypothetical situations involving interpersonal conflict. High- and moderate-anger groups scored significantly higher than low-anger subjects on a questionnaire measure of irrational thinking. High-anger subjects scored higher than low-anger subjects on general anxiety, suspiciousness, fear of negative evaluation, hostility, and criticism of themselves and others. Interview ratings showed that there were no group differences in self-reports of anger or ability to cope with conflict, yet raters judged high-anger subjects to display more anger than low-anger subjects in their stated response actions. Estimates of coping ability varied inversely with reports of anger experienced. Generally, results support a relationship between irrational thinking patterns and anger in feeling and action. Implications for treatment are discussed.  相似文献   
170.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号