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941.
Brain damage due to an episode of hypoxia remains a major problem in infants causing deficit in motor and sensory function. Hypoxia leads to neuronal functional failure, cerebral palsy and neuro-developmental delay with characteristic biochemical and molecular alterations resulting in permanent or transitory neurological sequelae or even death. During neonatal hypoxia, traditional resuscitation practices include the routine administration of 100% oxygen, epinephrine and glucose. In the present study, we assessed the changes in the cholinergic system by measuring the acetylcholinesterase (AChE) activity and the behavioral responses shown by hypoxia induced neonatal rats and hypoxic rats supplemented with glucose, oxygen and epinephrine using elevated plus-maze and open-field test. The acetylcholine esterase enzyme activity showed a significant decrease in cerebral cortex, whereas it increased significantly in the muscle of experimental rats when compared to control. Hypoxic rats supplemented with glucose, glucose and oxygen showed a reversal to the control status. Behavioral studies were carried out in experimental rats with elevated plus-maze test and open-field test. Hypolocomotion and anxiogenic behavioral responses were observed in all experimental rats when compared to control, hypoxic rats supplemented with glucose, glucose and oxygen. Thus, our results suggest that brain damage due to hypoxia, oxygen and epinephrine supplementation in the neonatal rats cause acetylcholine-neuromuscular-defect leading to hypolocomotion and anxiogenic behavioral response. Glucose and glucose with oxygen supplementation to hypoxic neonates protect the brain damage for a better functional status in the later life. 相似文献
942.
Objective
To study the effects of green tea extract administration on age-related cognition in young and old male Wistar rats.Methods
Young and old rats were orally administered 0.5% green tea extract for a period of eight weeks and were evaluated by passive avoidance, elevated maze plus paradigm and changes in acetylcholinesterase activity.Results
Treatment of young and old rats with the extract resulted in no significant difference in performance on the rota rod treadmill test/righting reflex time. Green tea extract significantly improved learning and memory in older rats, with increased retention latency to enter difference in passive avoidance test. In the elevated maze test, green tea treatment resulted in significantly more number of entries in the enclosed arm by the young and old rats. Decline in acetylcholinesterase activity was observed in the cerebrum of green tea treated old rats in comparison to the green tea treated young rats.Conclusion
Green tea extract administration is effective in enhancing learning and memory in aged rats, and hence, may serve useful in reversing age-related deficits. 相似文献943.
944.
In [W. Burr, Functional interpretation of Aczel's constructive set theory, Annals of Pure and Applied Logic 104 (2000) 31–73] Wolfgang Burr presents a functional interpretation of constructive set theory in all finite types, , in a theory of constructive set functionals. is a subtheory of , containing bounded quantifiers only. His interpretation theorem reduces the consistency problem of (and certain extensions thereof) to the consistency problem of .We want to study admissible rules in , i.e. rules under which is closed. To do so, we study a Troelstra-style q-hybrid of, in fact, a modification × of Burr's translation. We introduce this modification in order to close a minor gap in Burr's proof of the functional interpretation of the schema of (Strong Collection).First of all, but surely after a short introduction, we analyse the less complex translation of modified realisation mr and its hybrids mq and mrt. 相似文献
945.
Linda J. Herbert Lynnda M. Dahlquist 《Journal of clinical psychology in medical settings》2008,15(4):261-269
This study examined autonomy, anxiety, depression, and perceptions of parental behavior in 86 food allergic young adults and
344 healthy young adults between the ages of 18 and 22. Participants completed an online survey measuring self-reported autonomy,
anxiety, depression, and perceptions of parental behavior. Results indicated that, as a group, food allergic young adults
did not differ from healthy peers. However, food allergic young adults who reported having experienced an anaphylactic reaction
described their disease as more severe, reported more worry about their disease, and rated their parents as more overprotective
than food allergic young adults who reported never having experienced anaphylaxis. The experience of anaphylaxis may be a
reliable indicator of food allergic individuals who are at risk for psychological distress.
A portion of this research was presented at the National Conference on Child Health Psychology in Miami, Fl in April, 2008. 相似文献
946.
Peter E. Hodgson 《Zygon》2000,35(3):505-516
It has been suggested that God can act on the world by operating within the limits set by Heisenberg's uncertainty principle (HUP) without violating the laws of nature. This requires nature to be intrinsically indeterministic. However, according to the statistical interpretation the quantum mechanical wavefunction represents the average behavior of an ensemble of similar systems and not that of a single system. The HUP thus refers to a relation between the spreads of possible values of position and momentum and so is consistent with a fully deterministic world. This statistical interpretation of quantum mechanics is supported by reference to actual measurements, resolves the quantum paradoxes, and stimulates further research. If this interpretation is accepted, quantum mechanics is irrelevant to the question of God's action in the world. 相似文献
947.
Darrell P. Rowbottom 《Studia Logica》2007,87(1):65-71
It is a common view that the axioms of probability can be derived from the following assumptions: (a) probabilities reflect
(rational) degrees of belief, (b) degrees of belief can be measured as betting quotients; and (c) a rational agent must select
betting quotients that are coherent. In this paper, I argue that a consideration of reasonable betting behaviour, with respect
to the alleged derivation of the first axiom of probability, suggests that (b) and (c) are incorrect. In particular, I show
how a rational agent might assign a ‘probability’ of zero to an event which she is sure will occur. 相似文献
948.
Adalira Sáenz-Ludlow 《Studies in Philosophy and Education》2007,26(3):205-223
Historically the words representation and symbol have had overlapping meanings, meanings that usually disregard the role played
by the interpreter. Peirce’s theory of signs accounts for these meanings and also for the role of the interpreter. His theory
draws attention to the static and dynamic nature of signs. Sign interpretation can be viewed as a continuous dynamic and evolving
process. The static and dynamic nature of signs helps us understand the teaching–learning activity as a process of interpretation
on the part of teacher and students. The paper attempts to explain the classroom interpretation process on the part of the
actors involved using the Peircean theory of signs. 相似文献
949.
This study compared anxiety levels and coping strategies in Israeli adults during the Al-Aqsa Intifada (n = 707) and under ballistic missile attacks targeted at Israeli civilians during the Persian Gulf War (n = 328). In view of the differences among the two disaster situations in terms of severity of impact, scope, duration, predictability, and controllability, it was hypothesized that higher levels of state anxiety would be observed for the terror attack than for the missile attack crisis. Furthermore, problem-focused coping was predicted to be more salient than emotion-focused coping during the Gulf War—at a time where more protective action could be taken. Overall, the data supported the hypotheses. The data are discussed and explicated in the context of stress and coping theory and research. 相似文献
950.
Michael D. Robinson Brian P. Meier Benjamin M. Wilkowski Scott Ode 《Journal of research in personality》2007
Three studies involving 176 undergraduates examined the personality-related correlates of tendencies to slow down following errors in choice reaction time tasks. Such tendencies were hypothesized to tap individual differences in threat reactivity processes and therefore be relevant to the prediction of phobic-like fear (Study 1) and displayed anxiety as rated by informants (Studies 2 and 3). However, on the basis of the idea that high levels of extraversion may suppress threat reactivity processes, it was hypothesized that extraversion and post-error slowing tendencies would interact in predicting the dependent measures. The studies supported the latter interactive hypothesis in that post-error slowing tendencies were predictive of displayed anxiety at low, but not high, levels of extraversion. The discussion focuses on the respective roles of error-reactivity processes and extraversion in predicting behavioral inhibition and displayed anxiety. 相似文献