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Methods: Total muscle paralysis was induced under general anesthesia in a group of obese persons (n = 9; body mass index, 32 +/- 3 kg sup -2) and in a group of nonobese persons (n = 9; body mas index, 21 +/- 2 kg sup -2). Nocturnal oximetry confirmed that none of them had sleep-disordered breathing. The cross-sectional area of the pharynx was measured endoscopically at different static airway pressures. A static pressure-area plot allowed assessment of the mechanical properties of the pharynx. The influence of mandibular advancement on airway patency was assessed by comparing the static pressure-area relation with and without the maneuver in obese and nonobese persons.
Results: Mandibular advancement increased the retroglossal area at a given pharyngeal pressure, and mandibular advancement increased the retropalatal area in nonobese but not in obese persons at a given pharyngeal pressure. 相似文献
Subjects Children were separated into three groups: (a) HIV-infected with growth retardation (HIV+Gr); (b) HIV-infected with normal growth (HIV+); (c) HIV-uninfected with normal growth (HIV-). All children were afebrile and free of acute infection at the time of study. During a 24-hour stay in the Pediatric Clinical Research Unit, blood was drawn for analysis of total protein, albumin, zinc, selenium, and vitamin A levels; growth measurements were obtained; and dietary intake was assessed by 24-hour weighed food intake and 24-hour dietary recall.
Statistical analysis Mean differences between groups were assessed by analysis of variance, and differences in the frequency of nutrient deficiency were determined by χ2 analysis.
Results Thirty-eight children between 2 and 11 years of age were studied: 10 HIV+Gr, 18 HIV+, and 10 HIV-. No statistically significantly differences were noted in mean levels of albumin, prealbumin, zinc, and selenium. Mean serum level of vitamin A was significantly higher in the HIV+Gr group than in the other two groups. There were no significant differences between groups in the frequency of deficiency for any nutrient studied. Mean energy and nutrient intake was similar among groups.
Applications/conclusions Abnormal serum or plasma protein or micronutrient levels were uncommon in this cohort of HIV-infected children, even in children with growth retardation. Routine monitoring of the level of proteins and micronutrients studied is unnecessary in the absence of specific clinical indicators of deficiency. J Am Diet Assoc. 1997-97:1377-1381. 相似文献
Methods: An Intubation Difficulty Scale (IDS) was developed, based on parameters known to be associated with difficult intubation. It was then evaluated prospectively in a group of 311 consecutive prehospital intubations and 315 intubations in an operating room. In the operating room, the IDS was compared with two other parameters: the time to completion of intubation and the visual analog scale (VAS). Time was measured by an independent observer. Operators in both groups completed a checklist regarding the conditions of intubation.
Results: There is a good correlation between the IDS scale and the VAS assessment of difficulty and time to completion of intubation. VAS and time to completion have a significant but lesser correlation to each other. Comparison of IDS with operator-assessed subjective categorical impression of difficulty by Kruskall-Wallis was statistically significant. 相似文献