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991.
J Hidalgo E Belloso J Hernandez T Gasull A Molinero 《Stress (Amsterdam, Netherlands)》1997,1(4):231-240
The metallothionein (MT) gene family consists of four members (MT-I through -IV) that are tightly regulated during development. Whereas MT-I and MT-II are widely expressed isoforms, MT-III has been found to be mainly expressed in the central nervous system in adult animals, and is the only isoform that inhibits survival and neurite formation of cortical neurons in vitro. A number of models of brain injury have been shown to affect MT-III mRNA levels, which has been suggested to be related to the putative neurotrophic role of this protein. However, a stress response will presumably be associated to the brain injury which could, in turn, drive MT-III regulation. In the present report the effect of a classical stress model, immobilization stress, on brain MT regulation has been studied in rats. MT-I+II protein levels were measured by radioimmunoassay in up to eight brain areas and, as expected, it was found that stress increased selectively MT-I+II levels. Adrenalectomy (ADX) had a general decreasing effect on basal MT-I+II levels; however, ADX blunted the MT-I+II response to stress in cerebellum and presumably in frontal cortex and medulla plus pons but not in the hypothalamus. MT-I mRNA measurements were in accordance with the MT-I+II protein levels in the brain areas studied. In contrast to MT-I mRNA, MT-III mRNA levels of brain cortex tended to decrease during stress, although this effect was not statistically significant. ADX also tended to decrease basal MT-III mRNA levels. Northern blot assays of pooled mRNAs suggested similar differential regulation of these two brain MT isoforms in the cerebellum. These results indicate that glucocorticoids mediate brain MT-I+II response to stress in some but not all brain areas, that a role of these hormones is likely also for MT-III, and that the regulation of MT isoforms differs substantially in the brain. 相似文献
992.
The Convention on Human Rights and Biomedicine developed by the Council of Europe, now undergoing ratification, is the first international treaty focused on bioethics. This article describes the background of the Convention's development and its general provisions and provides a comparison of its requirements with those of federal regulations governing research with human subjects. Although most provisions are comparable, there are significant differences in scope and applicability, for example, in the areas of compensation for injury, research participation by persons with limited capacity to consent, assisted reproduction, organ transplantation, and research in emergency situations. The Convention represents a milestone in international bioethics and protection of human rights that will probably be referred to with increasing frequency. 相似文献
993.
Childress JF 《Kennedy Institute of Ethics journal》1997,7(4):403-411
Managed care organizations can produce conflicts of obligation and conflicts of interest that may lead to problems of conscience for health care professionals. This paper provides a basis for understanding the notions of conscience and conscientious objection and offers a framework for clinicians to stake out positions grounded in personal conscience as a way for them to respond to unacceptable pressures from managers to limit services. 相似文献
994.
Based on a previous study, a causal model of acquisition of pilot job knowledge and flying skills was tested on separate samples of male and female students. Causal model parameters were estimated separately for each sample and, due to the small sample size for women, no between-groups statistical tests were conducted. The results are viewed as tentative because of the small sample of female students; however, the path coefficient parameter estimates are still useful. The model showed a direct influence of general cognitive ability (g) on the acquisition of job knowledge and an indirect influence on the acquisition of flying skills. The direct and indirect influence of cognitive ability on flying skills was a little stronger for women than for men. Additionally, the path between prior job knowledge (JKp) and flying performance was somewhat stronger for women than for men. Consistent with previous findings, the influence of early flying skills on later flying skills was very strong. No argument for a sex-separated training syllabus is supported. 相似文献
995.
The focus of this paper is mechanisms that may be responsible for intellectual and developmental differences in the cognitive strategies of typical and atypical children, including those with mental retardation. The discussion of these mechanisms is based on behavioral experiments on external memory strategies and on a set of neural network models designed for these tasks. Following the review of the external memory research, the rationale for using neural network models, how they have been used in other research, and their specific application to intellectual and developmental differences in external memory, including the results of several simulations, are reviewed. This is followed by a discussion of the mechanisms of intellectual differences and developmental change included in the models and some challenges for this type of modeling. Neural network modeling is discussed as an asset to research on cognitive development. 相似文献
996.
R.F. Holland 《Philosophical Investigations》1997,20(3):246-256
Fanciful fates is a discussion of ideas put forward by D.Z. Phillips in his book Wittgenstein and Religion , Ch. 13 –'Authorship and Authenticity: Kierkegaard and Wittgenstein'. I begin by opposing the contention that Kierkegaard attacked Socrates (and that Josiah Thompson, one of Kierkegaard's biographers, attacked Kierkegaard) because of a worry connected with the 'the demise of foundationalism'. I then deal with Phillips's claim that a similarly motivated attack on Wittgenstein has been undertaken by me. I show that Phillips's account of my treatment of two problematic remarks by Wittgenstein is radically misconceived and I argue that his own approach to the problem is unsatisfactory. 相似文献
997.
Two studies of college undergraduates (ns = 95 and 92, primarily non-Hispanic whites and Asian Americans) investigated gender stereotypes of stress and emotion, as
well as variables that influence the perception of gender-related differences. Study 1 assessed how gender stereotypes differ
from the self-reports of men and women. When asked to choose a label for the subjective experience of the average man and
the average woman in a series of problematic hypothetical situations, participants generally tended to believe that the average
female would feel ‘emotional,” but that the average male would feel “stressed.” By contrast, the label participants chose
to describe their own subjective experience was not significantly affected by their gender. In addition, participants believed
the average woman and man differed more in the intensity of their emotions than in the intensity of their stress, a belief
contradicted by their own self-reports. Results of Study 2 indicated that gender-related differences in estimations of stress
and emotion for the self were reduced or eliminated when specific information about experience-eliciting situations was provided.
We would like to thank Matthew Dank for his help in preparing the stimulus materials. 相似文献
998.
The influence of children’s age, and parents’ and children’s gender on parents’ attributions and emotional and behavioral
responses to their children’s successful and unsuccessful social and academic outcomes, was investigated. Seventy-six dual-parent
families (mothers and fathers) of fifth (n=28), eighth (n=23), and eleventh grade (n=25) children participated. The results of this study suggest that from fifth grade on, at least, the ways parents explain
the causes of and respond to their children’s social behavior and academic outcomes involves a complex interaction of children’s
age, children’s gender, parents’ gender, domain, and outcome. Results are discussed in terms of children’s socialization.
This paper is based in part on a master’s thesis at Clark University by the first author. An earlier version of this paper
was presented at the annual meeting of the Eastern Psychological Association, Providence, RI, April 1994. The authors would
like to thank the parents, teachers, and school administrators of Holden and Auburn, Massachusetts, who participated in this
project. We would also like to thank Kristen Rotis and Leslie Edwards for their tireless help in revising and preparing the
questionnaires, and for entering data for this project. 相似文献
999.
This article demonstrates that there is a role for behavior-analytic techniques in the area of farm animal welfare and provides examples of the kinds of work that can be done. Behavior-analytic procedures, specifically those used in the study of psychophysics, preference, and demand, can provide answers to three questions people concerned with the welfare of farm animals are likely to ask: What can the animals detect? What do they like and dislike? What will they work to attain or preserve? Such information certainly is necessary for making reasonable decisions about animal welfare, although it is not sufficient in and of itself. 相似文献
1000.
Although Michael Polanyi's model of science and his construal of the nature of the real are usually thought to be congenial to religion and although Polanyi himself says that "the stage on which we thus resume our full intellectual powers is borrowed from the Christian scheme of Fall and Redemption" (Polanyi 1958, 324), theologians have given little attention to the model of God he presents. The metaphysical and theological vision unfolded in part 4 of Personal Knowledge is a thoughtful alternative to materialist versions of neo-Darwinism and provides a platform for revisiting four long-standing controversies at the interface of science and religion: whether life and mind can be completely specified in terms of physical analysis, whether nature can be adequately understood without appeal to final causes, whether natural selection adequately explains life's diverse forms, and whether knowledge can be fully objectified. Through an exploration of Polanyi's contribution to these discussions, we undertake to show not only that his treatment of God as a cosmic field is strikingly original but also that in reinstating activity as a metaphysical category, he reconstructs our understanding of our creaturely hope and calling. 相似文献