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31.
The study of the venous channels in the cavernous sinus in 48 sphenoid bones was performed. Thirty-eight bones were electrolyticly decalcified, subsequently embedded in gelatin, and cut in 1 mm thick slices. Microdissection of the other ten specimens complemented the analysis. Every specimen had the venous structure arranged as a plexus, however, although the channels were variable in number, form, and diameter, the two sides were quite symmetrical. Channels of smaller diameter predominated anteriorly. There was no demonstrable muscular layer in these vessels; the endothelial lining was easily visualized. Fatty tissue separated the venous channels from each other and from arteries and nerves. The distance from the carotid artery and the lateral wall increased anteriorly, but there were significant veins between these two structures in only 35% of the cases. In about one third of specimens the oculomotor nerve was placed over the carotid artery. The abducens nerve was found to be intimately related to the lateral wall without any venous channels between them in 92% of the specimens.  相似文献   
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Little is known about the quality of pharmacy services provided to the rural elderly population. This exploratory study examines rural/urban and ethnic differences in perceived access to ancillary pharmacy services among elderly people. Two telephone surveys were conducted using directory listings in West Texas to generate a longitudinal sample. Persons aged 65 years and older who were not cognitively impaired were asked to complete the survey. The number of participants in both rounds of the survey was 3,689. Seven ancillary pharmacy services were examined: delivery of medications, medication counseling, written medication information, blood pressure monitoring, blood glucose monitoring, osteoporosis screening, and immunization. The sample was stratified by county of residence (urban, rural, or frontier) and racial/ethnic background. Chi-square tests were performed to detect rural/urban and racial/ethnic differences in access to the seven ancillary services. The association between proficiency in English and access to the services was also examined. Rural residents were more likely than urban residents to report that their pharmacies provide delivery of medications, medication counseling, and immunization services, but they were less likely than their urban counterparts to report that their pharmacies provide blood pressure monitoring. Access to ancillary pharmacy services was reported as poorer by older Hispanic people compared with non-Hispanics. Deficiency in English was significantly related to inequality in reported access to ancillary pharmacy services. It is essential to consider the special needs of rural and Hispanic elderly people to ensure equitable access to ancillary pharmacy services.  相似文献   
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We report on a boy with severe radial hypoplasia, absent thumbs and patellae, short stature, persistent diarrhea, slender nose and normal intelligence as another example of the RAPADILINO syndrome. © 1992 Wiley-Liss, Inc.  相似文献   
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Although glucocorticoids are widely used to stimulate fetal/neonatal lung function, they also interfere with cellular development in the central nervous system. Dexamethasone was administered to pregnant rats in late gestation at a dose (0.8 mg/kg) that lies just above the threshold for stimulation of lung surfactant synthesis, and the impact on ornithine decarboxylase (ODC) was evaluated in three brain regions. Dexamethasone treatment produced an initial inhibition of basal ODC activity followed by postnatal elevations, a pattern known to be associated with delays in cell replication and differentiation. Dexamethasone also interfered with the ability of the 1-day-old neonate to turn off ODC acutely in response to a 2-h period of maternal separation; as this response conserves energy in the absence of the dam, the effect of dexamethasone is maladaptive. Additionally, dexamethasone sensitized the neonatal brain to hypoxia: the acute increase of ODC associated with a 2-h exposure to 7% O2 was exacerbated in 8-day-old rats exposed to dexamethasone prenatally. These results suggest that administration of dexamethasone, in doses that promote respiratory competence, delays cell development in the central nervous system and renders the brain more vulnerable to adverse neonatal conditions, such as maternal separation or hypoxia.  相似文献   
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PURPOSE: A prospective radiographic study analyzed condylar position in patients who had undergone orthodontic treatment and isolated maxillary advancement after Le Fort I osteotomy. PATIENTS AND METHODS: Eleven patients were selected and radiographic images were taken in the immediate preoperative, immediate postoperative (1-2 weeks), and late postoperative periods (minimum of 6 months). Tracings were done on acetate paper for the submento-vertex radiograph, to measure the axial angulation of the condyles, and for the tomographic images of both sides, in the maximal intercuspation, rest position, and maximal opening, for the 3 periods. Linear measurements were taken for the tomograms over the posterior, superior, and anterior articular spaces. These images with the tracings were digitized and measured by means of computer software (UTHSCSA Image Tool 3.0; University of Texas Health Science Center at San Antonio, San Antonio, TX), after it had been adequately calibrated. RESULTS: The analysis of variance (ANOVA; 5% of significance) demonstrated 1) that there was no statistically significant difference for the linear measurements of the articular spaces in any of the periods, and 2) also not for the angular measure of the condyles (P > .05). In the maximal opening, there was a significant difference for the immediate postoperative period for both sides (P = .003). CONCLUSION: Le Fort I osteotomy for maxillary advancement did not cause any significant changes in this specific group of patients evaluated.  相似文献   
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