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101.
In this observational study, we sought to assess the usefulness of pH values from residuals in intensive care unit (ICU) patients with small-bore feeding tubes. A review of the literature demonstrated that most critically ill patients were excluded in previous studies on gastric pH testing, suggesting that pH testing in critical care is not warranted. Our results demonstrated that 21% of intestinal testing and 64% of gastric testing yielded potential misinformation to the bedside nurse with regards to possible tube location. In conclusion, pH testing for small-bore tube placement and maintenance was not deemed meaningful in our critical care unit.  相似文献   
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ABSTRACT: The Dartmouth Health Promotion Study was a longitudinal, quasi-experimental field study with a qualitative research arm, designed to learn whether coordinating school health instruction, health services, and a healthful environment enhanced the program's effect on the heart health and mental health of children. The research strategy — the Coordinated Approach — was applied to approximately 300 children in each of two cohorts in grades four to six attending nine trial schools; a further 600 children attended 10 comparison schools in Dartmouth and nine distal comparison schools. Although the qualitative analysis demonstrated that positive feelings were engendered in most areas of the study, when either the classroom or the individual was used as the unit of analysis, the Coordinated Approach did not have a more favorable effect on the heart or mental health of children than did the standard school health program. Thus, the effect of an existing school health program was not directly enhanced through coordinating its components.  相似文献   
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Brain tissues from 6 patients with concentric sclerosis (Baló) were examined by in situ hybridization, immunocytochemistry, morphometry, and histological methods. The patients were 24 to 48 years old and had progressive cerebral symptoms and signs that lasted 15 to 100 days. Large demyelinative lesions, most frequent in the frontal white matter, contained alternating bands of demyelinated and partly myelinated white matter that were arranged in concentric or mosaic patterns. In the areas of demyelination, axons were relatively well preserved and there were perivascular inflammatory infiltrates. In 2 specimens, lesions contained regions with the characteristic appearance of actively demyelinating multiple sclerosis plaques. Oligodendroglial densities were highest in normal-appearing white matter, lower in partially myelinated areas, and lowest in demyelinated areas, which also contained many hypertrophic astrocytes closely associated with oligodendroglia. Messenger RNA levels for myelin-related proteins followed the same pattern; they were lowest in demyelinated areas, higher in partially myelinated areas, and highest in normal-appearing white matter beyond lesion margins. Our findings suggest that concentric sclerosis is a variant of multiple sclerosis, that oligodendroglial loss is important in the pathogenesis of demyelination, and that partially myelinated areas probably represent stages of ongoing myelin breakdown rather than remyelination of previously demyelinated areas.  相似文献   
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Summary In order to measure ejection fractions (EFs) from nuclear ventriculograms, we devised a semi-automated edge-detection technique based on a combination of inverse Fourier analysis and second-derivative techniques. Initial clinical studies showed that, for the left ventricle, our method gives EF values statistically identical with those obtained using a conventional isocontour technique. For the right ventricle, however, the values obtained using the two methods were somewhat more at variance. Despite requiring a longer processing time, the results obtained with our method are reproducible because less operator intervention is necessary.  相似文献   
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We investigated the immunohistochemical localization of CD44, hyaluronate receptor, and moesin, of the ezrinradixin-moesin (ERM) family, in osteoclasts after calcitonin adminstration using confocal laser scanning microscopy and transmission electron microscopy to clarify the role of CD44 and moesin in their cytoskeletal organization and cell polarity. We also elucidated the localization of osteopontin (OPN) to confirm its possible role in cell-matrix recognition via CD44. In untreated mice, intense immunoreactivities for CD44 and moesin were detected on the basolateral plasma membrane of osteoclasts. Rhodamine-phalloidin reactivity was seen in a bandlike pattern on the region of contact between osteoclasts and bone and was also detected moderately along their basolateral plasma membrane. At 30 min after calcitonin administration, osteoclasts did not show either clear zones or ruffled borders. The bandlike reactivity of rhodamine-phalloidin in the contact region was diminished, although labeling was seen along osteoclasts. CD44 and moesin were colocalized along their plasma membranes, including the region facing the bone surface. Electron microscopic observation revealed that the microvillus processes in the contacting region with bone surface, as well as the basolateral plasma membrane, showed immunoreactivities to CD44 and moesin. At 60 min, some osteoclasts attached to bone and showed a bandlike pattern of rhodamine-phalloidin. On the other hand, OPN was localized under CD44-positive cytoplasmic processes and the clear zone of osteoclasts. These findings suggest that calcitonin effects on the cell polarity of osteoclasts and the CD44-moesin-actin filament system in osteoclasts plays an imporant role in cell polarity and cell-matrix recognition.  相似文献   
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The AIDS epidemic has caused hysteria among the public and concern to many healthcare workers in the past 12 years. Currently, legislation exists for mandatory AIDS testing in some populations. The questions remain: Should healthcare workers be routinely tested? If so, is mandatory testing ethical? The author explores the incidence and prevalence of AIDS among healthcare workers, discusses why mandatory testing for healthcare workers is an issue, and examines the legal and ethical principles involved in mandatory testing.  相似文献   
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