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   66439篇
  免费   2789篇
  国内免费   23篇
  2020年   788篇
  2019年   939篇
  2018年   1309篇
  2017年   1367篇
  2016年   1421篇
  2015年   1029篇
  2014年   1245篇
  2013年   6070篇
  2012年   2288篇
  2011年   2327篇
  2010年   1410篇
  2009年   1446篇
  2008年   2068篇
  2007年   2013篇
  2006年   1838篇
  2005年   1599篇
  2004年   1630篇
  2003年   1571篇
  2002年   1529篇
  2001年   2106篇
  2000年   1958篇
  1999年   1517篇
  1998年   798篇
  1997年   699篇
  1996年   739篇
  1995年   692篇
  1994年   672篇
  1993年   672篇
  1992年   1253篇
  1991年   1132篇
  1990年   1122篇
  1989年   1061篇
  1988年   1032篇
  1987年   975篇
  1986年   964篇
  1985年   1032篇
  1984年   889篇
  1983年   789篇
  1982年   641篇
  1981年   607篇
  1979年   871篇
  1978年   717篇
  1977年   608篇
  1976年   608篇
  1975年   724篇
  1974年   818篇
  1973年   797篇
  1972年   670篇
  1971年   622篇
  1968年   661篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Recipient's mood, relationship type, and helping   总被引:6,自引:0,他引:6  
We conducted two studies to examine how a potential helper is affected by having a communal orientation toward a relationship with a potential recipient and by the potential recipient's sadness. We hypothesized that (a) having a communal orientation would increase helping and that (b) people high in communal orientation, but not others, would respond to a potential recipient's sadness by increasing helping. These hypotheses were tested in two studies. In Study 1, individual differences in communal orientation toward relationships were measured by using a new communal orientation scale reported for the first time in this article. In Study 2, manipulations were used to lead subjects to desire either a communal or an exchange relationship with another person. In both studies, subjects were exposed to a sad person or to a person in a neutral mood whom they were given a chance to help. As hypothesized, in both studies communally oriented subjects helped the other significantly more than did others. Also as hypothesized, in both studies communally oriented subjects but not others, increased helping in response to the other person's sadness although this effect reached statistical significance only in the second study.  相似文献   
992.
A short-form measure of loneliness   总被引:5,自引:0,他引:5  
The revised UCLA Loneliness Scale (ULS-20) and a four-item short form (ULS-4) are widely used in personality research (Russell, Peplau, & Cutrona, 1980). In an exploratory factor analysis of the ULS-20, we identified eight items that loaded substantially on the first factor. These items were combined to form an alternative short-form measure, the ULS-8. The results of this study indicate that the ULS-8 is reliable, valid, and a better substitute for the ULS-20 than is the ULS-4. Consistent with the previous research, the loneliness measures (ULS-20, ULS-8, ULS-4) were strongly related to socially undesirable personality characteristics, but loneliness was uncorrelated with the six different health-related behaviors (exercise, meal regularity, alcohol use, hard drug use, smoking, and hours of sleep) assessed in this study.  相似文献   
993.
The purpose of this study was to explore differences in body satisfaction among female adolescents 14 to 18 years of age. Principal components analysis of a body cathexis measure completed by 751 high school cheerleaders indicated that six factors defined the adolescents' attitudes toward their bodies: satisfaction with the midsection and overall appearance, peripheral body parts, hair and face, mouth, hands, and height. An Age X Body Satisfaction multivariate analysis of variance (MANOVA) was conducted; a Bonferroni adjusted alpha of .007 was established for subsequent ANOVAs. Satisfaction with the mouth increased significantly as age increased, and a similar but nonsignificant trend was found for peripheral body parts. The findings contradict previous research reporting no age differences in the body satisfaction of adolescents. Role demands and physical maturation of the cheerleaders may explain differences based on age.  相似文献   
994.
To determine whether actual responses of potential comforters in the community differ according to cause of death, 83 college students participated in a structured, individual interview. They were asked demographic questions about themselves, the bereaved, and the deceased, and then about various aspects of how they, and others in the community, responded to the death. Students were grouped by their reports of the cause of death (suicide, homicide, accident, natural anticipated death, or natural unanticipated death). When the death was by suicide or homicide, others were perceived as relatively less supportive of the bereaved person. When the death was by suicide, respondents themselves tended more to blame the bereaved person. When the death was by homicide, the bereaved person was perceived as reacting relatively worse. Potential comforters were relatively more shocked when the death was by homicide or accident.  相似文献   
995.
996.
Two experiments addressed the effects of food satiation and deprivation on oral self-administration of two concurrently available phencyclidine concentrations. In the first experiment, 8 rhesus monkeys self-administered either of two concentrations of phencyclidine ("PCP, angel dust") and water under concurrent fixed-ratio 16 schedules. One concentration was always held constant (0.25 mg/mL) while a series of other phencyclidine concentrations, ranging from 0 (water) to 1.0 mg/mL, was presented in a nonsystematic order. Initially the monkeys were tested while food satiated, and the procedure was then repeated during food deprivation. The monkeys usually selected the higher concentration within the first few minutes of the session, indicating that taste and/or other immediate postingestional effects were important factors. Contrary to a number of previous reports, there were no consistent differences across subjects in the mean number of liquid deliveries or mean drug intake (mg/kg) during food satiation and deprivation. However, for all monkeys the within-session time course of responding during food satiation consistently differed from that during deprivation. A second experiment assessed whether the failure to find consistent differences in drug intake during food satiation and deprivation had been due to the history of concurrent access to different phencyclidine concentrations or to the extended experience with phencyclidine under food-satiation conditions. Six additional monkeys (Group 2) were exposed to the phencyclidine self-administration procedure (during food satiation and deprivation) for the same length of time as the monkeys in Experiment 1 (Group 1), except they received only concurrent access to phencyclidine (0.25 mg/mL) and water. Both groups then received concurrent access to phencyclidine and water during five repeated cycles of food deprivation and satiation. There were also marked individual differences in Group 2: During food satiation, 2 of the monkeys' responding increased, 1 showed no change, and 3 decreased. Examination of a number of historical variables indicated that the greater the percentage of total sessions spent during food satiation with phencyclidine available (before these experiments began), the greater the amounts of phencyclidine consumed during food satiation and the smaller the differences in phencyclidine intake when the two feeding conditions were compared.  相似文献   
997.
This article deals with appropriate communication and interpersonal skills that nurses may use in order to support patients who are experiencing self-concept changes related to their health problems. Three areas of patient need related to self-concept are explored. The stages of adaptation to loss and the crucial task of grief work are reviewed, and nursing interventions designed to strengthen the self-concept and support patients as they adapt to loss are suggested. Sensitive communication, although a low-visibility nursing skill, is cited as critical in assisting the patient to achieve an optimum level of wellness.  相似文献   
998.
Six pigeons were trained in a discrete-trials signal-detection procedure to discriminate between a fixed-duration stimulus (5 s or 20 s) and a set of variable durations ranging from 2.5 s to 57.5 s in steps of 5 s. For each fixed-duration stimulus, the ratio of reinforcer frequencies contingent upon reporting the fixed versus the variable stimulus was systematically manipulated. Detection performance was well controlled by both the stimulus value and the reinforcer ratio. Both the discriminability between the fixed duration and the set of variable durations, and the discriminability between the fixed duration and each of the variable durations, were independent of the reinforcer-frequency ratio when discriminability was measured as log d. The sensitivity of response bias to reinforcement-ratio changes was independent of the value of the fixed duration, but was not independent of the discriminability of the variable durations from the fixed durations. Under current models, discriminability measures in complex temporal discrimination may be independent of biasing manipulations, but bias measures are not independent of stimulus values.  相似文献   
999.
Pigeons' choices between alternatives that provided different percentages of reinforcement in mixed schedules were studied using the concurrent-chains procedure. In Experiment 1, the alternatives were terminal-link schedules that were equal in delay and magnitude of reinforcement, but that provided different percentages of reinforcement, with one schedule providing, reinforcement twice as reliably as the other. All pigeons preferred the more reliable schedule, and their level of preference was not systematically affected by variation in the absolute percentage values, or in the magnitude of reinforcement. In Experiment 2, preference for a schedule providing 100% reinforcement over one providing 33% reinforcement increased systematically with increases in the duration of the terminal links. In contrast, preference decreased systematically with increases in the duration of the initial links. Experiment 3 examined choice with equal percentages of reinforcement but unequal delays to reinforcement. Preference for the shorter delay to reinforcement was not systematically affected by variation in the absolute percentage of reinforcement. The overall pattern of results supported predictions based on an extension of the delay-reduction hypothesis to choice procedures involving mixed schedules of percentage reinforcement.  相似文献   
1000.
Religious and spiritual issues in mental health are explored in the context of four conceptual models: the medical, the nursing, the humanistic, and the pastoral. This is done by looking at each model in terms of content, diagnostic focus, language and treatment goals, and primary qualities in the health provider.The models are illustrated by case studies gathered from a multidisciplinary setting. The discovery that each model can incorporate the religious and spiritual dimension in mental health care, but that each model does this in distinctive ways, is a key point.  相似文献   
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