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The actions of prolonged treatment of rats within imipramine or lithium chloride on the β-adrenergic cAMP generating system of the cerebellum were compared in normal animals and in rats degranulated by neonatal X-irradiation. Whereas in normal animals imipramine treatment is without significant effect on the cerebellar cAMP system but lowers the β-adrenoceptor density significantly, in degranulated animals the cAMP system becomes subsensitive towards norepinephrine after prolonged imipramine treatment. These data support the hypothesis that in the cerebellum imipramine acts predominantly on β-adrenoceptors located particularly on Purkinje cells. Prolonged lithium treatment exhibited no significant effects on β-receptors nor the noradrenergic cAMP generating system of normal and degranulated cerebella.  相似文献   
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Voluntary and forced exercise decrease morbidity and mortality in laboratory animals. Caloric restriction has similar effects on health and unique benefits on life span. Nonetheless, in most experiments, animals do not have access to physical activity and are fed ad libitum (AL). We hypothesized that with regular access to either unlimited running wheel exercise (EX) or limited physical activity (PA), key biomarkers of health would be enhanced enough to counter some consequences of a sedentary AL lifestyle. This 16-month study compared body weight, tumor number and size, tissue lesions, oxidative stress, and reactive stress in (1) sedentary animals with no access to physical activity (SED); (2) animals with access to hour-long, twice weekly activity in a large box (PA); and (3) animals with access every other day to a running wheel (EX). At the end of the study, EX body weight was 8-9% lower than PA and SED. In addition, EX had no kidney lesions versus 50% in PA and SED, and had smaller tumor size (10+/-2 vs. 14+/-4 and 30+/-4 mm). Exhaustive exercise lowered glutathione/oxidized glutathione ratio in EX and PA, but in SED, the ratio was depressed even in resting animals. In all treatments, prolactin (PRL) levels were lower in resting animals than in acutely exercised animals. In conclusion, EX had the most favorable health biomarkers while SED had the least. PA did not confer gross health benefits different than the SED group, but was biochemically more similar to EX animals.  相似文献   
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The purpose of this study was to develop an instrument that measures pharmacy student work values. The instrument was included in a questionnaire mailed to 1,820 pharmacy students who had just graduated or were in their last year of pharmacy school from 19 schools of pharmacy nationwide. A total of 738 questionnaires were deemed usable for a usable rate of 41.5 percent. After Varimax factor analysis, eleven reliable factors emerged: Quality Patient Care; Supervision and Company Policy; Work Creativity/Variety; Status; Management/Leadership; Economic Return; Work Schedule; Family Responsibilities; Job Security; Co-worker Relationships; and Policies and Procedures. "Job Security," "Family Responsibilities," and "Patient Care" were rated least and negatively important respectively. There were no differences between BS and PharmD degree aspirants on the eleven factors; however, there were some significant differences between sexes. Women rated "Supervision and Company Policy" and "Quality Patient Care" higher than men. Men did not negatively value "Work Schedule" as much as women did, i.e., women preferred to work traditional, weekday hours.  相似文献   
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Paired clicks were presented to awake, freely-moving rats to examine neuronal activity associated with inhibitory gating of responses to repeated auditory stimuli. The rats had bundles of eight microwires implanted into each of four different brain areas: CA3 region of the hippocampus, medial septal nucleus, brainstem reticular nucleus, and the auditory cortex. Single-unit recordings from each wire were made while the local auditory-evoked potential was also recorded. The response to a conditioning stimulus was compared to the response to a test stimulus delivered 500 ms later: the ratio of the test response to the conditioning response provided a measure of inhibitory gating. Auditory-evoked potentials were recorded at all sites. Overall, brainstem reticular nucleus neurons showed the greatest gating of local auditory-evoked potentials, while the auditory cortex showed the least. However, except for the auditory cortex, both gating and non-gating of the evoked response were recorded at various times in all brain regions. Gating of the hippocampal response was significantly correlated with gating in the medial septal nucleus and brainstem reticular nucleus, but not the auditory cortex. Single-unit neuron firing in response to the clicks was most pronounced in the brainstem reticular nucleus and the medial septal nucleus, while relatively few neurons responded in the CA3 region of the hippocampus and the auditory cortex. Taken together, these data support the hypothesis that inhibitory gating of the auditory-evoked response originates in the non-lemniscal pathway and not in cortical areas of the rat brain.  相似文献   
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The health insurance industry in the U.S. can be characterized as a concentrated industry. It has evolved into its current structure as a result of certain historical conditions, particularly those following the Great Depression. The structure of the industry has had an effect on the manner in which the industry functions and the cost increases in the health care sector. Specifically, the pricing mechanism is that of a price leader setting a limit price; health premium prices are higher than would be expected under a competitive structure. Regulation has been ineffective, because it has been dominated historically by health care providers and insurers. The costs of health care in general, and hospital care in particular, have increased beyond what would be expected as a result of "cost-pass-through."  相似文献   
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One hospital's experience with a "Do not resuscitate" policy.   总被引:3,自引:3,他引:0       下载免费PDF全文
A "No not resuscitate" policy was instituted at McMaster University Medical Centre, Hamilton, in January 1979. Its objectives were to ensure that physicians decide on the appropriateness of resuscitation attempts before they might be needed; to have each physician consult his or her patients, or the families of incompetent patients, to determine their wishes concerning further treatment; and to provide legal protection of or physicians and the hospital in regard to the policy. To determine the effectiveness of the "Do not resuscitate" policy a questionnaire was sent to a sample of the professional staff of the hospital; the overall response rate was 87%. The respondents felt that a better way of informing hospital staff of the policy and its objectives was needed. However, the results of the questionnaire suggested that, on the whole, the policy was perceived as beneficial to both patients and physicians at the hospital.  相似文献   
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