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101.
During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity.  相似文献   
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The effect of weight loss with anorectic medications on sleep apnea, non-insulin-dependent diabetes, and steatohepatitis is illustrated in three cases from practice in a clinical nutrition setting. Prevention of obesity, a chronic disorder, is preferable, but when obesity becomes a major obstacle in the care of patients with respiratory, cardiovascular, and metabolic disorders and osteoarthritis, an intense course of weight reduction using anorectic medications under medical and dietetic guidance is essential for patients' survival and reduction of medical cost.  相似文献   
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We reviewed plain radiographs of 215 pediatric patients with surgically proven appendicitis to study the value of plain radiography for diagnosis.  相似文献   
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OBJECTIVE: Our objective was to assess the effectiveness of skin care protocols, including a body wash and skin protectant, on skin breakdown in 2 nursing homes. DESIGN: This was a quasi-experimental pretest/posttest design study.Setting and subjects Adult residents (n = 136) of 2 skilled nursing homes consented to participate in this study. Seventy percent were women; the sample average age of 82 years. INSTRUMENTS: A researcher-designed data recording form documented resident demographics, incidence and type of skin breakdown or pressure ulcer, presence of urinary or fecal incontinence, and assessment of the effectiveness of body wash and skin protectant. METHODS: Baseline data on prevalence of pressure ulcers and skin protocol were collected weekly for a 3-month period followed by a week-long educational program by the researchers about skin care and the body wash and skin protectant. During the 3-month trial with the body wash and skin protectant incorporated into routine care, research assistants recorded resident data weekly and researchers again assessed prevalence and incidence of pressure ulcers and skin breakdown weekly. RESULTS: Incorporation of a body wash and skin protectant into a skin care prevention and early intervention protocol in 2 nursing homes documented a decrease in skin breakdowns from 68 pre-intervention to 40 postintervention; the decrease in agency B was statistically significant. There was a statistically significant decrease in stage I and II pressure ulcer incidence overall (pre-intervention = 19.9%, postintervention = 8.1%). Nurses evaluated the body wash and skin protectant as effective for 98% of the time used. CONCLUSION: Implementation of a protocol for skin care along with staff education, including the prophylactic use of a body wash and skin protectant, reduced the incidence of skin breakdown, including pressure ulcers and perineal dermatitis, in 2 long-term care facilities.  相似文献   
108.
Glucose is the obligate energetic fuel for the mammalian brain, and most studies of cerebral energy metabolism assume that the majority of cerebral glucose utilization fuels neuronal activity via oxidative metabolism, both in the basal and activated state. Glucose transporter (GLUT) proteins deliver glucose from the circulation to the brain: GLUT1 in the microvascular endothelial cells of the blood-brain barrier (BBB) and glia; GLUT3 in neurons. Lactate, the glycolytic product of glucose metabolism, is transported into and out of neural cells by the monocarboxylate transporters (MCT): MCT1 in the BBB and astrocytes and MCT2 in neurons. The proposal of the astrocyte-neuron lactate shuttle hypothesis suggested that astrocytes play the primary role in cerebral glucose utilization and generate lactate for neuronal energetics, especially during activation. Since the identification of the GLUTs and MCTs in brain, much has been learned about their transport properties, that is capacity and affinity for substrate, which must be considered in any model of cerebral glucose uptake and utilization. Using concentrations and kinetic parameters of GLUT1 and -3 in BBB endothelial cells, astrocytes, and neurons, along with the corresponding kinetic properties of the MCTs, we have successfully modeled brain glucose and lactate levels as well as lactate transients in response to neuronal stimulation. Simulations based on these parameters suggest that glucose readily diffuses through the basal lamina and interstitium to neurons, which are primarily responsible for glucose uptake, metabolism, and the generation of the lactate transients observed on neuronal activation.  相似文献   
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The effectiveness of educational activities on changing the handwashing habits of preschool children was evaluated using parental surveys and direct observations. Baseline handwashing behaviors were observed and recorded, and parents completed a pre-intervention survey. After interventions were administered, post-intervention data was collected on preschoolers' handwashing habits. Children participated in one, three or five handwashing intervention activities. Results of this study indicate that the educational activities implemented resulted in increased knowledge of the importance of proper handwashing and in positive changes in the children's handwashing habits, particularly for the children who participated in all five interventions.  相似文献   
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