全文获取类型
收费全文 | 16148篇 |
免费 | 625篇 |
国内免费 | 4篇 |
出版年
2019年 | 213篇 |
2018年 | 258篇 |
2017年 | 221篇 |
2016年 | 257篇 |
2015年 | 171篇 |
2014年 | 262篇 |
2013年 | 1275篇 |
2012年 | 432篇 |
2011年 | 486篇 |
2010年 | 290篇 |
2009年 | 313篇 |
2008年 | 417篇 |
2007年 | 441篇 |
2006年 | 423篇 |
2005年 | 347篇 |
2004年 | 372篇 |
2003年 | 334篇 |
2002年 | 329篇 |
2001年 | 453篇 |
2000年 | 511篇 |
1999年 | 342篇 |
1998年 | 205篇 |
1997年 | 154篇 |
1996年 | 168篇 |
1995年 | 165篇 |
1992年 | 277篇 |
1991年 | 288篇 |
1990年 | 296篇 |
1989年 | 277篇 |
1988年 | 269篇 |
1987年 | 235篇 |
1986年 | 249篇 |
1985年 | 260篇 |
1984年 | 193篇 |
1983年 | 207篇 |
1982年 | 158篇 |
1980年 | 156篇 |
1979年 | 248篇 |
1978年 | 217篇 |
1977年 | 150篇 |
1975年 | 215篇 |
1974年 | 242篇 |
1973年 | 269篇 |
1972年 | 225篇 |
1971年 | 210篇 |
1970年 | 162篇 |
1969年 | 197篇 |
1968年 | 249篇 |
1967年 | 239篇 |
1966年 | 209篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
971.
Female rats, chronically treated with Testosterone Propionate (TP), were injected with Fluprazine (DU 27716) or saline and tested for social aggression, masculine and feminine sexual behavior. Fluprazine-treated females were less aggressive than saline-treated females, as indicated by a shift from offensive to less offensive parameters of aggression. At the same time, mounting in Fluprazine-treated females was almost totally abolished, both in aggression tests and in tests for sexual behavior. Feminine sexual responses increased during aggressive encounters but were slightly inhibited when females were confronted with sexually active males. Females treated with Fluprazine and tested for mounting with a receptive female showed a substantial increase of offensive aggression directed at the receptive stimulus female. It is concluded that Fluprazine does not selectively inhibit offensive aggression in TP-treated female rats. 相似文献
972.
Aggressive and sexual behaviour was studied in 5-min paired encounters between castrated prepubertal boars (N = 14) and normal (N = 2) or bulbectomized (N = 2) oestrogen-treated ovariectomized gilts. The boars were made sexually active by treatment with 17β-oestradiol + 5α-dihydrotestosterone. Half of the boars were sprayed on the snout with a solution containing a mixture of the boar pheromones 3α-androstenol and 5α-androstenone immediately before testing, and the remainder were treated with the vehicle solution. Aggression was almost always initiated by the gilts, and neither bulbectomy nor pheromone treatment of the boars reduced its occurrence. The results suggest that the display of aggression by gilts towards boars of similar body size is unlikely to be suppressed by the steroidal pheromones present in boar saliva. 相似文献
973.
The development of hand preference in infancy was investigated longitudinally by using a visually-directed reaching task. Thirty-two infants, equally divided into groups of familial right- and left-handed boys and girls, were tested every 3 weeks from 24 to 39 weeks of age and once again at 52 weeks. Group trends for the development of hand preference were differentiated by familial handedness and sex of the infant. At all ages, test object position (to the infant's right or left) strongly influenced the hand used for reaching. Marked variability both between and within infants demonstrated an instability of early hand preference, an effect that could be appreciated fully only with a prospective longitudinal design. The results thus suggest that the development of hand preference for reaching is highly variable, discontinuous, and related to the interaction of sex and familial handedness. 相似文献
974.
Only recently has determining the child-rearing concerns of parents been considered an important research objective. Existing efforts have, for the most part, either employed small sample sizes or surveyed parents already in the process of seeking help or advice. It was, therefore, felt that additional, more representative data were needed. In the present study, 583 mothers with children aged 59 months or younger were surveyed regarding their concerns about their children's development. On the „Specific Needs Assessment Report”︁ (SNAR) (copyright © 1975, by Karl F. Riem, J. Jeffrey Crisco, and Kathy Willms), mothers rated their concerns for 60 developmental-behavioral items about their children's health, attending skills, problem behaviors, communication skills, motor skills, cognitive skills, self-help skills, and social skills. Mothers were most frequently concerned to a moderate or major degree about at least one item of the problem behavior category. For this category, parent-child management, crying-whining, and temper tantrums were the individual items of greatest concern. Mothers of girls more frequently indicated health concerns than mothers of boys. These results support those of previous investigations, which suggested the need for parent education programs to help parents manage their children. 相似文献
975.
976.
977.
This experiment demonstrated that rats trained to display elevated levels of shock-induced aggression in a negative reinforcement paradigm displayed more boxing behavior than yoked control groups in a later test in which intruder rats were placed in the home cage of resident rats. Resident or intruder status did not affect the influence of the negative reinforcement procedure on the observed resident-intruder behavior of trained animals; however, naive intruders paired with trained residents displayed increased defensive behavior, suggesting that negative reinforcement for shock-induced aggression affected the behavior of these residents. 相似文献
978.
F. A. Lootsma 《Journal of Multi-Criteria Decision Analysis》1993,2(2):87-110
We consider first a variant of the analytic hierarchy process (AHP) with a one-parametric class of geometric scales to quantify human comparative judgement and with a multiplicative structure: logarithmic regression to calculate the impact scores of the alternatives at the first evaluation level and a geometric-mean aggregation rule to calculate the final scores at the second level. We demonstrate that the rank order of the impact scores and final scores is scale-independent. Finally we show that the multiplicative AHP is an exponential version of the simple multi-attribute rating technique (SMART). In fact, the multiplicative AHP is concerned with ratios of intervals on the dimension of desirability, whereas SMART analyses differences in the corresponding orders of magnitude. 相似文献
979.
McCay Vernon Lawrence J. Raifman Sheldon F. Greenberg 《Behavioral sciences & the law》1996,14(1):121-135
Administration of the Miranda Warnings to deaf suspects poses many legal issues. If police officers, judges, attorneys and psychologists are unaware of these, evidence obtained as a consequence of deaf suspects waiving their Miranda Rights may be inadmissible in court. These issues include the importance of videotaping the police interview, the use of sign language interpreters, the determination of the deaf defendant's reading level and communication capacity, the limitations of lipreading, and other psycholinguistic factors. Recommendations are offered to aid in determining whether a deaf suspect is capable of understanding the Miranda Warnings and how these warnings should be administered. 相似文献
980.
Stefano Parmigiani Marisa Mainardi Paul F. Brain Marc Haug Vanna Brunoni 《Aggressive behavior》1989,15(3):191-200
Behavioral, physiological (i.e., endocrine), and anatomical consequences of crowding in mice were studied in a situation where animals were in auditory, visual, olfactory, and tactile contact but restrained from full physical interactions, to prevent overt aggression. Males that cohabited with females undisturbed by neighboring conspecifics showed greater propensity to attack same-sex intruders and had higher plasma testosterone levels than did their “crowded” counterparts, that is, males cohabiting with females and housed adjacent to other male/female pairs. In this respect, the latter animals resembled submissive males. However, a significant increase in weight of androgen-dependent target organs (i.e., seminal vesicles and preputial glands) was found in crowded males. These data indicate that despite the observed inhibition of social aggression these males are not physiologically comparable (homologous) to male mice that experienced defeat and the stress of submission during fighting. The intriguing possibility that different conversion pathway of testosterone are accelerated, as a result of social communication, in males living in these two environments and the behavioral implications of these possibilities are discussed. Finally, the parental behavior of crowded animals, although not freely interacting with each other, was disrupted, causing a marked decrease in reproductive success. In this situation a high incidence of infanticide of their offspring by both parents was observed, whereas this behavior was virtually absent in non-crowded male/female pairs. 相似文献