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51.
A Thalamic Contribution to Arousal-induced, Non-photic Entrainment of the Circadian Clock of the Syrian Hamster 总被引:3,自引:0,他引:3
Elizabeth S. Maywood Emma Smith Stephanie J. Hall Michael H. Hastings 《The European journal of neuroscience》1997,9(8):1739-1747
It is well established that the circadian clock of the suprachiasmatic nuclei (SCN) is entrained by light. More recently, the potent effects of arousing, non-photic cues on the clock have been recognized. The neural mediators of non-photic entrainment are yet to be identified. To examine the contribution of the thalamic intergeniculate leaflet (IGL) and its NPY-immunopositive projection, the geniculo-hypothalamic tract to non-photic entrainment by arousal, male Syrian hamsters received lesions of the IGL (IGLX) which ablated NPY-immunoreactivity in the SCN. Their circadian responses to both photic and non-photic cues were then tested. Lesions resulted in a delay in the timing of activity onset following lights out, but had no effect on the behavioural or cellular circadian responses to phase-advancing light pulses presented at circadian time (CT) CT19 (where CT12 represents the time of activity onset). Injection with a benzodiazepine (chlordiazepoxide, 100 mg/kg) at CT6 suppressed wheel-running, increased general locomotion of intact controls and induced large phase advances of the circadian rhythm of wheel-running. Chlordiazepoxide also inhibited wheel-running in lesioned animals, but there was no significant increase in general locomotion and the lesioned animals did not phase advance. Serial arousal by injection of saline at intervals of 23.5 h for 6 days entrained the circadian rhythm of wheel-running of intact hamsters and was associated with an increase in general locomotor activity. Entrainment by serial arousal was abolished by IGLX. However, the lesioned animals did show a clear behavioural response to every presentation of the non-photic cue. These results show that the IGL is a necessary component of the neural pathways mediating both arousal- and benzodiazepine-induced non-photic entrainment. 相似文献
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L H Hollier F I Smith J C Rice C H Kliger M D Kerstein 《American journal of surgery》1990,160(2):179-181
This investigation was designed to study the effects of home health care (HHC) on patients who have been hospitalized with peripheral vascular disease. For a patient to have HHC, the patient had to have a defined wound, educational needs, or both. Sixty patients, 30 with HHC and 30 without, were contacted approximately 30 days after their last hospital discharge. The 30 patients with HHC were deemed to be at increased risk because of multisystem disease with multiple medications, infirmity, early senility, and often complex wounds. In a prospective fashion, each patient was interviewed by either a registered nurse or medical student using a standardized data collection form. The following issues were assessed: incidence of postoperative complications, knowledge of the patient of his or her disease, compliance with medication (knowledge of, regular use), incidence of readmission, and unscheduled clinic or emergency department visits. Upon statistical analysis using the two-sample t-test and Pearson chi-square test, no significant differences were found between the two groups in terms of complications, compliance, or patient education. HHC, therefore, was found to be helpful to patients with peripheral vascular disease. In our study, the use of HHC made the risk of complications in a group of patients with defined teaching needs and wound care needs equal to that in a group with no such defined needs on discharge from the hospital. 相似文献
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Outcome for patients colonised with Burkholderia cepacia in a Birmingham adult cystic fibrosis clinic and the end of an epidemic. 总被引:2,自引:2,他引:0 下载免费PDF全文
K Muhdi F P Edenborough L Gumery S O''Hickey E G Smith D L Smith D E Stableforth 《Thorax》1996,51(4):374-377
BACKGROUND: There has been increasing concern since 1979 about the emergence of Pseudomonas cepacia (Burkholderia cepacia) in patients with cystic fibrosis in the UK and elsewhere. Colonisation of the sputum has been shown to be associated with increased morbidity and mortality. Evidence suggests person to person transmission and some centres have segregated those colonised with B cepacia from other patients with cystic fibrosis. The outcome of patients colonised by B cepacia has been studied, together with the effects of strict segregation. METHODS: The outcome in 18 patients with sputum colonised by B cepacia was compared with that in age, sex, and severity matched controls with no evidence of B cepacia colonisation by a retrospective case note study. RESULTS: No difference between cases or controls were found in the 24 month period prior to colonisation by B cepacia in lung function, number of days in hospital, or outpatient visits. Colonisation led to an increased rate of loss of lung function and utilisation of hospital services. There was an increase in the numbers of transplants and deaths amongst the cases. Since 1992 there have been only three new cases of B cepacia colonisation and the incidence and prevalence of the organism has fallen dramatically since segregation commenced. CONCLUSIONS: B cepacia appears to be linked to the decline in colonised individuals. There was no evidence that colonisation occurred in patients declining for other reasons. B cepacia colonisation confers a worse prognosis than Pseudomonas aeruginosa alone. Segregation appears to limit the spread of the organism from infected individuals to other patients with cystic fibrosis. 相似文献
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目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study. 相似文献