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991.
992.
The existing literature is controversial regarding the relationship between physical fitness and intraocular pressure (IOP). Therefore, the effects of acute submaximal exercise on IOP were compared in athletes and sedentary subjects. Acute exercise increased IOP in male athletes, but had no effect in sedentary men. Also, it decreased IOP in sedentary women, but had no effect in female athletes. Sex and physical fitness both were significant factors influencing the changes in IOP due to exercise. These results suggest that acute dynamic exercise is useful to decrease IOP in sedentary women, but not in male athletes. These results may help glaucoma screeners.  相似文献   
993.
994.
The aim of this study was to evaluate the effects of atorvastatin as an antioxidant and tissue protective agent and study the biochemical and histopathological changes in experimental ischemia and ischemia/reperfusion (I/R) injury in rat ovaries. The experiment used 48 adult female rats, and the experimental groups can be summarized as: group I, a sham operation; group II, a sham operation +10 mg/kg atorvastatin; group III, bilateral ovarian ischemia; and groups IV and V, bilateral ovarian ischemia +5 and 10 mg/kg atorvastatin before 30 min of ischemia, respectively (after a 3-h period of ischemia, the bilateral ovaries were surgically removed); group VI, 3-h period of ischemia followed by 3-h reperfusion; groups VII and VIII received 5 and 10 mg/kg atorvastatin, respectively, 2.5 h after the induction of ischemia, and at the end of a 3-h period of ischemia, bilateral vascular clips were removed and 3-h reperfusion continued. After the experiments, superoxide dismutase (SOD) and myeloperoxidase (MPO) activity and levels of glutathione (GSH) and lipid peroxidation (LPO) were determined, and histopathological changes were examined in all rat ovarian tissue. Ischemia and I/R increased the LPO level and MPO activity while decreasing the SOD activity and GSH level significantly in comparison to the sham group. The 5- and 10-mg/kg doses of atorvastatin before ischemia and I/R reversed the trend in LPO level and MPO activity. The levels of SOD and GSH were decreased by ischemia and I/R. The administration of atorvastatin before ischemia and I/R treatments also reversed the trend in the SOD and GSH levels. In the I/R plus atorvastatin groups, although minimal vascular dilation in the ovary stoma and some degenerative cell clusters were seen, most of the cellular structures showed no pathological changes. Administration of atorvastatin is effective in reversing tissue damage induced by ischemia and/or I/R in ovaries.  相似文献   
995.
996.
This paper makes three points. First, inferences from biological and psychological evidence pertaining to psychological constructs must use distinct vocabularies because they represent different phases of a cascade of processes. Second, there are necessarily indeterminate relations between phases of the cascade that begins with an incentive evoking a brain state which, in turn, may generate a psychological reaction and/or action. Finally, all biological and psychological phenomena occur in particular species and specific contexts; hence it is useful to append to every conclusion information on the agent and the setting in which the evidence was gathered.  相似文献   
997.
998.
Models of Dysfunction in Developmental Psychopathology   总被引:3,自引:0,他引:3  
The central thesis of this article Is that several premises and strategies that guide research on psychopathology in children and adolescents greatly limit our understanding of the characteristics, onset, and course of functioning and adaptation. Specifically, the article questions the assumption of single pathways of dysfunction, the focus on main effects and linear relations, the preference for analyzing psychological dimensions rather than categories of individuals, lack of attention to "packages" or clusters of influences and outcomes and to their dynamic relations, and, finally, indifference to the sources of information for assessing major constructs. The strategies that will augment understanding include: more diverse sources of information, aggregation of risk factors, analyses within individuals as well as within groups, models based on changes during development, and, finally, inquiry Into the processes that mediate psychopathology.  相似文献   
999.
Methamphetamine has been marketed illicitly since the 1960s. Much of the street material was illicitly synthesized. Although methamphetamine quality was variable in the past decade, it has emerged since 1978 as the only street stimulant which is likely to contain what it purports to contain. Although there is a small volume of legitimate methamphetamine still made by the pharmaceutical industry, most material analyzed by street-drug laboratories appears to have been illegitimately synthesized and not diverted. For a decade, relatively little methamphetamine was submitted to street-drug analytical labs. In recent years, although the absolute volume of methamphetamine submissions changed little, this drug made up the bulk of alleged stimulant samples submitted to such facilities because of the paucity of amphetamine submissions. Methamphetamine synthesis and use appears to constitute a small but continuing portion of the illicit drug market.  相似文献   
1000.
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