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1.
Evidence is presented in rodents, that individual differences in aggression reflect heritable, fundamentally different, but equally valuablealternative strategies to cope with environmental demands. Generally, aggressive individuals show an active response to aversive situations. In a social setting, they react with flight or escape when defeated; in non-social situations, they react with active avoidance of controllable shocks and with sustained activity during an uncontrollable task. In contrast, non-aggressive individuals generally adopt a passive strategy. In social and non-social aversive situations, they react with immobility and withdrawal.A main aspect of these two alternative strategies is that individuals with an active strategy easily develop routines (intrinsically determined behaviour), and consequently do not react (properly) to minor changes in their environment, whereas in passively reacting animals it is just the other way around (extrinsically determined behaviour). It has become clear that active and passive behavioural strategies represent two different, but equivalent, coping styles. The coping style of the aggressive males is aimed at the removal of themselves from the source of stress or at removal of the stress source itself (i. e. active manipulation). Non-aggressive individuals seem to aim at the reduction of the emotional impact of the stress (i.e. passive confrontation). The success of both coping styles depends upon the variability or stability of the environment. The fact that aggressive males develop routines may contribute to a fast excution of their anticipatory responses, which is necessary for an effective manipulation of events. However, this is only of advantage in predictable (stable) situations, but is maladaptive (e.g. expressed by the development of stress pathologies) when the animal is confronted with the unexpected (variable situations). The flexible behaviour of non-aggressive individuals, depending strongly upon external stimuli, will be of advantage under changing conditions.Studies on wild house mice living under natural conditions show how active and passive coping functions in nature, and how the two types have been brought about by natural selection.  相似文献   

2.
The relationships between anxiety/stress, possible endogenous ligands for benzodiazepine receptors and the behavioral modification by drugs are discussed in this short review, including the specific characteristics of elements involved in those interactions, e.g. ones concerning the aversiveness of the stressful situation and the nature of the organism under investigation. These are important factors when considering aversive tasks, insofar as they may involve stressful conditions which differ in intensity and in the degree of control afforded the subject. These characteristics may well lead to differing functional effects on GABA-gated chloride channels or, in other words, to an incongruous balance between endogenous benzodiazepine receptor agonist and inverse agonist activity. This is not surprising, as it is well known that different forms of stressors often actually produce divergent behavioral, physiological and biochemical effects. This review also illustrates the necessity of taking into account the variable effects of stressors and/or drugs on animals differing in reactivity or emotionality, even in the case of 'non-selected' stocks. The implication is made that, by genetic and/or environmental manipulation of the emotional state of the animals used, it will be possible to obtain more clearly definable results in neuropharmacological and psychopharmacological studies.  相似文献   

3.
The relationships between anxiety/stress, possible endogenous ligands for benzodiazepine receptors and the behavioral modification by drugs are discussed in this short review, including the specific characteristics of elements involved in those interactions, e.g. ones concerning the aversiveness of the stressful situation and the nature of the organism under investigation. These are important factors when considering aversive tasks, insofar as they may involve stressful conditions which differ in intensity and in the degree of control afforded the subject. These characteristics may well lead to differing functional effects on GABA-gated chloride channels or, in other words, to an incongruous balance between endogenous benzodiazepine receptor agonist and inverse agonist activity. This is not surprising, as it is well known that different forms of stressors often actually produce divergent behavioral, physiological and biochemical effects. This review also illustrates the necessity of taking into account the variable effects of stressors and/or drugs on animals differing in reactivity or emotionality, even in the case of non-selected stocks. The implication is made that, by genetic and/or environmental manipulation of the emotional state of the animals used, it will be possible to obtain more clearly definable results in neuropharmacological and psychopharmacological studies.  相似文献   

4.
5.
近年来,工作家庭冲突是组织行为学领域的研究重点。已有研究表明,这类因员工无法同时兼顾工作角色和家庭角色要。求而产生的角色间的冲突和压力,会对员工的生活满意感造成负面影响。本研究认为适宜的个人应对策略能够调节这两者之间的关系,通过对某国有企业193名被试的问卷调查,得出以下结论:1)工作-家庭冲突和家庭-工作冲突对生活满意感都有显著的负面影响;2)员工家庭优先策略能够缓解工作-家庭冲突对生活满意感的负面影响,员工工作完美策略能够缓解家庭,工作冲突所带来的压力感。  相似文献   

6.
This paper traces the origins of the styles project, originally presented as ‘styles of scientific reasoning’. ‘Styles of scientific thinking & doing’ is a better label; the styles can also be called genres, or, ways of finding out. A. C. Crombie’s template of six fundamentally distinct ones was turned into a philosophical tool, but with a tinge of Paul Feyerabend’s anarchism. Ways of finding out are not defined by necessary and sufficient conditions, but can be recognized as distinct within a sweeping, anthropological, vision of the European sciences. The approach is unabashedly whiggish. The emergence of these styles is part of what Reviel Netz calls cognitive history, and is to be understood in an ecological way. How did a species like ours, on an Earth like this, develop a few quite general strategies for finding out about, and altering, its world? At a more analytical level, the project invokes Bernard Williams’ notion of truthfulness to explicate the idea that these styles are ‘self-authenticating’ and without foundations. The paper concludes with open questions. What role (for example) have these few fundamentally distinct genres of inquiry played in the formation of the anomalous Western idea of Nature apart from Man?  相似文献   

7.
Life span and development time are considered in the context of the abiotic stresses to which free-living organisms are normally exposed. Under these circumstances, long life span depends upon metabolically efficient stress-resistance genes, which tend to be heterozygous. Similarly, rapid development time tends to be a feature of heterozygous stress-resistant individuals. Therefore, individuals who have high inherited stress resistance should develop fastest and live longest; in addition, they should show high homeostasis in the face of the energy costs of stress. In this way, the stress theory of aging can incorporate the developmental stage, based upon oxidative stress as an important major direct challenge.  相似文献   

8.
Stress proteins in neural cells: functional roles in health and disease   总被引:11,自引:0,他引:11  
Heat shock proteins (HSPs) or stress proteins participate in protein synthesis, protein folding, transport and translocalization processes. Stress situations trigger a heat shock response leading to their induction. Similarly, they can be upregulated by impairment of the proteasomal degradation pathway. The upregulation of stress proteins is an important step in prevention of protein aggregation and misfolding after stress, and also is essential during development and differentiation. A number of HSPs are constitutively or inducibly expressed in the nervous system and connected to protection of nerve cells and glia. The cytoskeleton is affected by stress, and HSPs have been shown to interact with the cytoskeleton in normal cells and to assist proper assembly, spatial organization and cross-linking properties. The integrity of the cytoskeleton is disturbed in many neurodegenerative disorders, and filamentous cytoplasmic inclusion bodies, containing a variety of HSPs, are observed. This review summarizes the recent literature on the presence and induction of HSPs in neural cells, and their possible functional roles in health and disease are discussed.  相似文献   

9.
Olfactory navigation in birds   总被引:3,自引:0,他引:3  
Summary Many bird species rely on an osmotactic mechanism to find food sources even at a considerable distance. Pigeons also rely on local odours for homeward orientation, and they integrate those perceived during passive transportation with those at the release site. It is possible to design experiments in which birds are given false olfactory information, and predictions about the effects of this can be made and tested. Pigeons build up their olfactory map by associating wind-borne odours with the directions from which they come; this was shown by experiments which aimed at preventing, limiting or altering this association. Some objections have been made to this conclusion; namely that even anosmic pigeons are sometimes homeward oriented, that they may be demotivated in flying or disturbed in their general behaviour, and that olfactory cues may be only one component of pigeo's navigational repertoire. The most recent experiments, however, confirm that pigeons derive directional information from atmospheric odouts. The lack of any knowledge about the chemical nature and distribution of the odorants which allow pigeons to navigate hinders progress in this area of research.  相似文献   

10.
A M Comunetti 《Experientia》1978,34(7):889-893
Many persons react to a kind of external agent by unconscious muscular reactions if they move across a place where this agent is supposed to be particularly active. Such places normally coincide with geological discontinuities, such as water veins, mineral ores. Practitioners of this art of detecting claim that the reaction patterns on different levels above ground are identical as vertical projections of the source pattern, this without perceptible attenuation. In some cases the supposed source was believed to have been found up to several hundred meters below ground surface. The statement of perpendicular propagation, which is the subject of this paper, is of prime importance for an approach towards understanding and all kinds of prospecting.  相似文献   

11.
One thing about technical artefacts that needs to be explained is how their physical make-up, or structure, enables them to fulfil the behaviour associated with their function, or, more colloquially, how they work. In this paper I develop an account of such explanations based on the familiar notion of mechanistic explanation. To accomplish this, I (1) outline two explanatory strategies that provide two different types of insight into an artefact’s functioning, and (2) show how human action inevitably plays a role in artefact explanation. I then use my own account to criticize other recent work on mechanistic explanation and conclude with some general implications for the philosophy of explanation.  相似文献   

12.
Summary The cycless musselsAnodonta cygnea andPseudanodonta complanata do not show any phototaxis. In the Zweilichterversuch (two-light-experiment) they react to the decrease of light intensity. If light is increasing, the mussels will not react; if put in the shade, they immediately do so. If the shadow is moved, the mussels even react when the intensity of light decreases much less, which demonstrates the importance of motion. From this it follows that the reception of motion may be considered as possible where there is light sensitiveness of the skin, and where the experiment connects motion with shading.  相似文献   

13.
Summary The competition of various cations with labelled zinc in the active (metabolic) uptake of the latter by chlorella has been measured. The series obtained does not coincide with that of the passive uptake in the same system, and the specificity is higher in the former case.  相似文献   

14.
Summary When hoarding food under IR light, the golden hamster returns to its nest by path integration after an active outward journey, and it is capable of compensating the angular component of a passive outward journey independently of auditory, olfactory, tactile and geomagnetic cues. If, however, peripheral visual cues are available, they predominate over information which is gained during the active or passive outward journey. Further experiments show the limitations of homing by path integration, which is open to cumulative errors and therefore needs to be complemented by other categories of information.Acknowledgments. This research was supported by the Fonds national suisse de la recherche scientique, grants No. 3.349.0.74 and 3.753.0.80. We are very grateful to Dr J. Bovet, Dr W. Heiligenberg, Dr J. G. Mather and to an unknown referee for their critical comments and to Mr R. Schumacher for all his ingenious technical help.  相似文献   

15.
Summary Anti-lipid-A, anti-endotoxin, antibodies have been measured by a passive haemolysis test using antigen from anE. coli Re mutant. Titres in the normal population are low but do rise in situations in which there has been gram-negative sepsis. Absence of raised titres in other situations has profound implications.We are most grateful to Dr Günter Schmidt of Freiburg for his gift of Lipid-A antigen. We also thank Dr L. Monnens of Nijmegen and Dr T.M. Barratt of London for their sera.  相似文献   

16.
Summary The behaviour of pure isolated DNA towards the conditions of fixation and dehydration—prior to ultrathin sectioning—has been studied and compared with the behaviour of the DNA-plasm of the bacterial nucleus. It is found that those conditions which produce coarse coagulation of the free DNA also produce electron opaque bodies of variable aspect inside the bacterial nucleus. The coagulation figures obtained in both situations are very similar. This is a further direct evidence in favour of the view that the bacterial nucleus is an assembly of fine DNA-containing fibrilla in a highly hydrated plasma.  相似文献   

17.
引种植物水竹芋捕虫行为的初步观察研究   总被引:1,自引:0,他引:1  
通过对引种植物水竹芋的观察,发现水竹芋的花具有捕捉昆虫的能力,在此基础上对其花进行了解剖结构特征和捕虫行为的观察,并初步探讨了其捕虫行为的生态学意义.观察研究显示,水竹芋开放花以及即将开放花的花柱具有较强的卷曲能力;未开放以及开放后没有被触及的花的花柱被兜状退化雄蕊包被;当昆虫进入饰变雄蕊群形成的筒状结构而触及到兜状退化雄蕊时,花柱因产生应激反应而迅速卷曲,从而将昆虫捕捉.初步观察研究认为,水竹芋不仅具有捕捉昆虫的能力,而且在水污染处理以及湿地的恢复与重建中具有重要的应用潜力.  相似文献   

18.
Summary Many persons react to a kind of external agent by unconscious muscular reactions if they move across a place where this agent is supposed to be particularly active. Such places normally coincide with geological discontinuities, such as water veins, mineral ores. Practitioners of this art of detecting claim that the reaction patterns on different levels above ground are identical as vertical projections of the source pattern, this without perceptible attenuation. In some cases the supposed source was believed to have been found up to several hundred meters below ground surface. The statement of perpendicular propagation, which is the subject of this paper, is of prime importance for an approach towards understanding and all kinds of prospecting.Acknowledgments. The author expresses his gratitude to Hoffmann-La Roche for support of the project, particularly to Prof. Dr. A. Pletscher, to the operators Dr P. Treadwell (TR) and Mr Rupp (RU) for their indefatigable participation, and to the operator M. Aeberli (AE) as well as to all persons who contributed to this investigation.  相似文献   

19.
Treatment of cloned pituitary cells (GH3/B6) with cholesterol-enriched liposomes, which presumably increases membrane cholesterol content, affects the passive and active electrophysiological properties and stimulates the release of prolactin (PRL).  相似文献   

20.
Summary Some correlations between the physicochemical properties of drugs and their pharmacokinetic behaviour are outlined. Based on the permeability characteristics of simple model membranes (porous membrane, lipid membrane) permeation and distribution of drugs in the animal body can be described and understood on simple physico-chemical terms. Some clinically important aspects — the absorption of drugs from the intestinal tract, the passage through the blood-brain-barrier and the renal excretion as governed by passive tubular reabsorption — are discussed in more detail. Thereby it appears that the solubility of a drug in lipid material, which may be suitably expressed as partition coefficient between an organic solvent and a buffer solution of pH 7.4, is a major factor in determining its pharmacokinetic behaviour.  相似文献   

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