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201.
Sex Roles - Hate speech in online users’ comments is often targeted toward underprivileged social groups such as immigrants, sexual minorities, and women. Besides the general severity of such... 相似文献
202.
Sven Ove Hansson 《Erkenntnis》1989,31(1):1-42
A possible world semantics for preference is developed. The remainder operator () is used to give precision to the notion that two states of the world are as similar as possible, given a specified difference between them. A general structure is introduced for preference relations between states of affairs, and three types of such preference relations are defined. It is argued that one of them, actual preference, corresponds closely to the concept of preference in informal discourse. Its logical properties are studied and shown to be plausible. 相似文献
203.
204.
Traffic research shares a fundamental dilemma with other areas of empirical research in which humans are potentially put at risk. Research is justified because it can improve safety in the long run. Nevertheless, people can be harmed in the research situation. Hence, we need to balance short-term risks against long-term safety improvements, much as in other areas of research with human subjects. In this paper we focus on ethical issues that arise when human beings are directly affected in the performance of research by examining how the ethical requirements in biomedical research can inform traffic research. After introducing the basic ethical requirements on biomedical research, each of the major requirements is discussed in relation to traffic research. We identify the main areas where biomedical research and traffic research differ, and where the ethical requirements from the former cannot easily be transferred to the latter. Finally, we argue that there is a need for systematic studies of the ethics of traffic research and point to some of the issues that need to be addressed. 相似文献
205.
Sven Ove Hansson 《Synthese》2009,171(2):257-269
Although choice and preference are distinct categories, it may in some contexts be a useful idealization to treat choices
as fully determined by preferences. In order to construct a general model of such preference-based choice, a method to derive
choices from preferences is needed that yields reasonable outcomes for all preference relations, even those that are incomplete
and contain cycles. A generalized choice function is introduced for this purpose. It is axiomatically characterized and is
shown to compare favourably with alternative constructions. 相似文献
206.
Sven Rosenkranz 《Erkenntnis》2011,74(2):177-206
We conceive of many general terms we use as having satisfaction conditions that are objective in that the thought that something
meets them neither entails nor is entailed by the thought that we are currently in a position in which we are ready, or warranted,
to apply those terms to it. How do we manage to use a given term in such a way that it is thereby endowed, and conceived to
be endowed, with satisfaction conditions that are objective in this sense? In the first half of the paper, I present a number
of interrelated problems for some extant metasemantical accounts of how use determines objective satisfaction conditions.
In the second half, I then propose a novel account that avoids all of these problems. 相似文献
207.
Human faces are among the most important visual stimuli that we encounter at all ages. This importance partly stems from the face as a conveyer of information on the emotional state of other individuals. Previous research has demonstrated specific scanning patterns in response to threat-related compared to non-threat-related emotional expressions. This study investigated how visual scanning patterns toward faces which display different emotional expressions develop during infancy. The visual scanning patterns of 4-month-old and 7-month-old infants and adults when looking at threat-related (i.e., angry and fearful) versus non-threat-related (i.e., happy, sad, and neutral) emotional faces were examined. We found that infants as well as adults displayed an avoidant looking pattern in response to threat-related emotional expressions with reduced dwell times and relatively less fixations to the inner features of the face. In addition, adults showed a pattern of eye contact avoidance when looking at threat-related emotional expressions that was not yet present in infants. Thus, whereas a general avoidant reaction to threat-related facial expressions appears to be present from very early in life, the avoidance of eye contact might be a learned response toward others' anger and fear that emerges later during development. 相似文献
208.
Reneerkens OA Rutten K Akkerman S Blokland A Shaffer CL Menniti FS Steinbusch HW Prickaerts J 《Neurobiology of learning and memory》2012,97(4):370-379
A promising target for memory improvement is phosphodiesterase type 5 (PDE5), which selectively hydrolyzes cyclic guanosine monophosphate (cGMP). In rodents, PDE5 inhibitors (PDE5-Is) have been shown to improve memory performance in many behavioral paradigms. However, it is questioned whether the positive effects in animal studies result from PDE5 inhibition in the central nervous system or the periphery. Therefore, we studied the effects of PDE5 inhibition on memory and determined whether compound penetration of the blood-brain barrier (BBB) is required for this activity. Two selective PDE5-Is, vardenafil and UK-343,664, were tested in the object recognition task (ORT) in both a MK-801- and scopolamine-induced memory deficit model, and a time-delay model without pharmacological intervention. Compounds were dosed 30 min before the learning trial of the task. To determine if the PDE5-Is crossed the BBB, their concentrations were determined in plasma and brain tissue collected 30 min after oral administration. Vardenafil improved object recognition memory in all three variants of the ORT. UK-343,664 was ineffective at either preventing MK-801-induced memory disruption or time-dependent memory decay. However, UK-343,664 attenuated the memory impairment of scopolamine. Vardenafil crossed the BBB whereas UK-343,664 did not. Further, co-administration of UK-343,664 and scopolamine did not alter the brain partitioning of either molecule. This suggests that the positive effect of UK-343,664 on scopolamine-induced memory decay might arise from peripheral PDE5 inhibition. The results herein suggest that there may be multiple mechanisms that mediate the efficacy of PDE5 inhibition to improve memory performance in tasks such as the ORT and that these involve PDE5 located both within and outside of the brain. To further elucidate the underlying mechanisms, the cellular and subcellular localization of PDE5 needs to be determined. 相似文献
209.
210.
To effectively wayfind through unfamiliar buildings, humans infer their relative position to target locations not only by interpreting geometric layouts, especially length of line of sight, but also by using background knowledge to evaluate landmarks with respect to their probable spatial relation to a target. Questionnaire results revealed that participants have consistent background knowledge about the relative position of target locations. Landmarks were rated significantly differently with respect to their spatial relation to targets. In addition, results from a forced-choice task comparing snapshots of a virtual environment revealed that background knowledge influenced wayfinding decisions. We suggest that landmarks are interpreted semantically with respect to their function and spatial relation to the target location and thereby influence wayfinding decisions. This indicates that background knowledge plays a role in wayfinding. 相似文献