全文获取类型
收费全文 | 34166篇 |
免费 | 614篇 |
国内免费 | 4篇 |
专业分类
34784篇 |
出版年
2020年 | 410篇 |
2019年 | 499篇 |
2018年 | 675篇 |
2017年 | 680篇 |
2016年 | 774篇 |
2015年 | 564篇 |
2014年 | 673篇 |
2013年 | 2997篇 |
2012年 | 1150篇 |
2011年 | 1172篇 |
2010年 | 784篇 |
2009年 | 760篇 |
2008年 | 1045篇 |
2007年 | 1084篇 |
2006年 | 930篇 |
2005年 | 843篇 |
2004年 | 852篇 |
2003年 | 803篇 |
2002年 | 823篇 |
2001年 | 918篇 |
2000年 | 897篇 |
1999年 | 711篇 |
1998年 | 405篇 |
1997年 | 348篇 |
1996年 | 325篇 |
1995年 | 341篇 |
1994年 | 320篇 |
1993年 | 309篇 |
1992年 | 563篇 |
1991年 | 552篇 |
1990年 | 525篇 |
1989年 | 499篇 |
1988年 | 522篇 |
1987年 | 480篇 |
1986年 | 468篇 |
1985年 | 491篇 |
1984年 | 422篇 |
1983年 | 370篇 |
1982年 | 314篇 |
1981年 | 321篇 |
1979年 | 449篇 |
1978年 | 361篇 |
1977年 | 298篇 |
1975年 | 341篇 |
1974年 | 430篇 |
1973年 | 422篇 |
1972年 | 320篇 |
1971年 | 316篇 |
1968年 | 366篇 |
1967年 | 318篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
901.
902.
International Journal for Philosophy of Religion - 相似文献
903.
Michael Hannon 《Philosophy and phenomenological research》2020,101(3):591-611
Epistemic democracy is standardly characterized in terms of “aiming at truth”. This presupposes a veritistic conception of epistemic value, according to which truth is the fundamental epistemic goal. I will raise an objection to the standard (veritistic) account of epistemic democracy, focusing specifically on deliberative democracy. I then propose a version of deliberative democracy that is grounded in non-veritistic epistemic goals. In particular, I argue that deliberation is valuable because it facilitates empathetic understanding. I claim that empathetic understanding is an epistemic good that doesn't have truth as its primary goal. 相似文献
904.
Synthese - This paper seeks to answer the following question: What is a minimal set of entities that form an ontology of the natural world, given our well-established physical theories? The... 相似文献
905.
J. Mos J. H. C. M. Lammers A. M. van der Poel B. Bermond W. Meelis M. R. Kruk 《Aggressive behavior》1983,9(2):133-155
Large electrolytic lesions were placed in the midbrain central gray of male rats. Their effects on hypothalamically induced aggression, switch-off behaviour, and locomotion were investigated. A number of these animals were also tested for territorial intermale aggression in order to compare electrically induced and spontaneous aggression. Large lesions resulted in an increase of the current threshold to induce aggression by hypo-thalamic stimulation. Smaller, but still quite large, lesions decreased the threshold current for hypothalamic aggression. After the operation a decrease in the threshold for switch-off was present, both in the experimental and the control group. Current thresholds for locomotion were decreased after the lesions only in the experimental group. Spontaneous aggression was temporarily decreased after the lesion. No indication was found that other behavioural elements of the animal were distorted by the lesion. The parallel between the effects on spontaneous and electrically induced aggression makes it attractive to ascribe a role to the neural circuit of hypothalamus and central gray in territorial aggression. However, even with large lesions the animals were still capable of fighting, hence the central gray is not indispensable. An attempt was made to explain the differential effects that differently sized central gray lesions have on hypothalamic aggression. 相似文献
906.
Michael Potegal 《Aggressive behavior》1979,5(4):353-373
Field observations of “surplus killing” and laboratory studies of operant performance rewarded by prey-killing opportunities suggest that predatory behavior is positively reinforcing. Similarly, both repeated encounter and operant performance studies suggest that intraspecific aggression can be positively reinforcing for successful aggressors. While a few studies suggest that defensive aggression under aversive conditions may also be positively reinforcing, it appears that when appropriate response modes are available escape and/or avoidance are preferred to attack. Studies of the reinforcing properties of aggression-eliciting brain stimulation are in general agreement with these conclusions, but methodological problems with these latter observations render them less compelling. The progressive escalation of aggression seen in “warm-up effects” of birds and fish, “priming effects” of mice, and ecstatic violence of humans may be analogous processes based on the positively self-reinforcing characteristics of some kinds of aggression. The transient reductions of aggression which appear as refractory periods and satiation effects in a variety of species may reflect temporary reductions in the reinforcing value of aggression. All these temporal effects must be considered in the evaluation of experiments on the reinforcing value of aggression. More generally, it is possible that these temporal fluctuations reflect the operation of common motivational processes (aggressive states) which regulate overt aggression by changing its reinforcing value. 相似文献
907.
908.
Rape has been posited to be an outgrowth of male reproductive strategies. Forced copulations may have evolved as a consequence of the low parental investment made by males in producing and raising offspring. We designed a laboratory experiment which paired rhesus macaque males with females in order to assess the influence of intersexual aggression on male sexual activity. Younger and older adult males had comparable levels of sexual behavior, but younger males were more aggressive towards females than were older males. In addition, females threatened younger males more than older males. Male attacks on females did not result in sexual intercourse. On the contrary, a negative correlation existed between male aggression towards females and male success at achieving intromissions. Female aggression towards males appeared to be an effective tactic which reduced the chances of sexual intercourse. We conclude that intersexual aggression acts either as a mechanism of dominance assertion or as a means to increase spatial distance between individuals. These data do not support the idea that rape in humans has an evolutionary foundation derived from male reproductive strategies. 相似文献
909.
Defensive aggression was examined in seven species of terns during the hatching period when young are most vulnerable and adults most responsive. Aggression toward an unfamiliar person varied with respect to species, flush distance, approach distance, number of birds overhead and diving, and number of dives per 2 min for all birds and the nest owner. Defensive aggression involved birds circling over and diving at the experimenter. Generally, flush distance was negatively correlated with nest density, while the number of birds diving was positively correlated with the nest density. The number of birds diving was positively related to the number of dives, dives by the owner, and the number overhead. 相似文献
910.
Rennig Johannes Wegner-Clemens Kira Beauchamp Michael S. 《Psychonomic bulletin & review》2020,27(1):70-77
Psychonomic Bulletin & Review - Visual information from the face of an interlocutor complements auditory information from their voice, enhancing intelligibility. However, there are large... 相似文献