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101.
102.
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   
103.
104.
Health education professional preparation programs were surveyed to determine the extent of HIV/AIDS education health educators are receiving. The survey also addressed content areas, skills being developed or enhanced, areas of deficiency in preparation programs, and areas in which national professional associations may assist in the preparation of AIDS educators. One hundred eight-three surveys were mailed; 114 (68%) were completed and returned. Twenty-one institutions reported planning a separate course on HIV/AIDS. Most were designing general service courses to reach a broad cross-section of students. Twenty-five institutions (23.8%) reported previously offering or currently offering a specific course on AIDS. One hundred two (89.5%) respondents reported HIV/AIDS warranted the attention and funding it had received. Thirty-seven (35.2%) respondents reported AIDS education was of sufficient importance to influence hiring of faculty members in their departments. Survey findings demonstrate that current AIDS education courses targeted to the general student population may not be adequate in meeting the professional preparation needs of health educators charged to provide AIDS education.  相似文献   
105.
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   
106.
The petrous carotid artery: anatomic relationships in skull base surgery   总被引:3,自引:0,他引:3  
Advanced transcranial lesions may be successfully resected through a variety of contemporary skull base approaches. The identification and isolation of the internal carotid artery throughout its petrous course is essential in most of these surgical techniques. Anatomic landmarks normally used to identify this vital structure, however, may be severely distorted by tumor involvement or previous operative dissection. In an effort to define surgical landmarks that may be used in the identification of the petrous carotid artery, histologic sections of 100 temporal bones from adults were examined and microscopic measurements were recorded from the anatomic dissection of 10 fresh cadaver halfheads. On the basis of these studies, structures we have found useful in identification of the vertical petrous carotid artery during lateral skull base approaches include the: base of the styloid process, bony vascular crest, basal turn of the cochlea, medial wall of the eustachian tube, and the cochleariform process. Identification of the horizontal segment can be achieved by the preliminary delineation of the middle meningeal artery, greater petrosal nerve, tensor tympani muscle, mandibular and maxillary divisions of the trigeminal nerve, and the eustachian tube. Specific anatomic relationships with associated measurements are detailed and correlated with selected, illustrative cases.  相似文献   
107.
108.
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   
109.
Intraperitoneal injection of 50 micrograms.kg-1 of the selective dopamine D-1 receptor antagonist, SCH 23390, significantly decreased sham feeding of 6% and 10% sucrose solutions, but not sham feeding of 100% corn oil. Intraperitoneal injection of raclopride, a D-2 antagonist, elicited a significant dose-dependent (200-400 micrograms.kg-1) decrease in sham intake of both sucrose concentrations and corn oil at doses that did not increase the latency to sham feed or produce overt motor impairment. The rank order of inhibitory potency for both SCH 23390 and raclopride was 6% sucrose greater than 10% sucrose greater than 100% corn oil. In a second experiment, we found that in 2-bottle preference tests, the rank order of preference for these three liquids was 100% corn oil greater than 10% sucrose greater than 6% sucrose. Assuming that preference measured the relative reward value of the liquids, the potencies of the two antagonists were inversely related to the reward value of the liquid that was sham fed. This result supports but does not prove the dopamine hypothesis of the positive reinforcing effect of orosensory stimulation by nutrients. In addition, the differential selectivity of the two antagonists for different classes of nutrients suggests that normal sensory and/or hedonic processing of sham-fed sucrose depends on stimulation of both D-1 and D-2 receptors, but the normal sensory and/or hedonic processing of sham-fed corn oil depends primarily, perhaps exclusively, on stimulation of D-2 receptors.  相似文献   
110.
P C Smith  S Sarin  J Hasty  J H Scurr 《Surgery》1990,108(5):871-875
The treatment of venous ulcers has remained largely unchanged for centuries. The application of properly applied graduated compression bandages, the use of graduated compression stockings, and surgery have been shown to achieve healing. However, some ulcers persist despite appropriate management. A randomized study was undertaken to compare two regimens of treatment for such patients. Both regimens included ulcer debridement, cleaning, nonadherent dressing, and graduated compression stockings. In one regimen, sequential gradient intermittent pneumatic compression was applied for 4 hours each day. Only one of 24 patients in the control group had complete healing of all ulcers compared with 10 of 21 patients healed in the intermittent pneumatic compression group. The median rate of ulcer healing in the control group was 2.1% area per week compared to 19.8% area per week in the intermittent pneumatic compression group. The results indicate that sequential gradient intermittent pneumatic compression is beneficial in the treatment of venous ulcers.  相似文献   
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