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We examined distribution characteristics of the body mass index (BMI; weight/height; kg/m2) in a sample of 1128 male and 1372 female Pima Indians aged 15-65 years. We found that women had a higher mean and variance of BMI than men. From commingling analyses, we determined that the distribution of BMI could be accounted for either by a single skewed distribution or by a mixture of multiple normal components. These component distributions may be used to define provisional thresholds in selecting families for genetic studies. To ensure genetic segregation of obesity predisposing genes in Pima families will require that some members have BMIs > or = 40 kg/m2.  相似文献   
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We undertook a prospective study of standard peripheral pulse oximetry versus a modified pulse oximeter probe applied to the tongue in order to determine the efficacy of this alternative monitoring site in children with thermal injuries. Ten patients with a mean age (± SD) of 7.5 ± 4.5 yr were studied on 15 occasions. The mean weight +- SD) was 31.4+- 13.7 kg and percent surface area burn (± SD) was 56+- 21%. A total of 1,992 min of anaesthesia time was monitored. Both sites functioned simultaneously 47% of the time; the lingual but not the peripheral site functioned 28% of the time and only the peripheral site and not the lingual functioned 22% of the time. Neither site functioned 3% of the time. The tongue oximeter provided 563 min more monitoring time than the peripheral sites. The tongue oximeter also functioned in children with peripheral vasoconstriction when the peripheral sensor failed and was less susceptible to electrocautery interference. The tongue oximeter is a reasonable adjunct but not a substitute for peripheral oximetry since its application is limited to paralyzed, intubated patients.  相似文献   
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Measurement of unchanged drug in urine was used to study the rate and extent of amoxycillin absorption after administration of amoxycillin sodium solution to six healthy subjects in a Latin-Square crossover design. The mean (95% CI) fraction of the dose excreted as unchanged amoxycillin decreased (P < 0.05) from 0.50 (0.44-0.56) after 97 mg amoxycillin sodium (= 0.25 mmol amoxycillin) to 0.23 (0.19-0.27) after 3103 mg (8 mmol), while the mean residence time determined from urinary excretion rate data increased (P < 0.05) from 1.54 (1.32-1.76) h to 2.16 (2.01-2.41) h. Plots of total urinary excretion and initial (0-30 min) excretion of unchanged drug vs dose indicated significant non-linearity above 776 mg doses. Michaelis-Menten parameters describing this relationship with respect to amount absorbed were 3.02 mmol for maximum amount absorbed and 1.93 mmol for amount absorbed at half maximum for 0-30 min. These results support a saturable absorption mechanism for amoxycillin which had clinical implications for high oral amoxycillin doses, and for competition with other drugs having capacity-limited absorption.  相似文献   
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The purpose of this study was to assess differences in bereavement outcomes between surviving spouses aged 50 and over who remarried within 4-5 years and those who did not. Fifteen bereaved respondents out of 192 in a longitudinal prospective study who later remarried were compared with 15 other matched nonremarried respondents. Analyses of sociodemographic data, standardized measures of depression, life-satisfaction, resolution of grief, and self-perceived ratings of coping, stress, self-esteem, health and social support were performed with correlated t-tests. Statistically significant differences indicated that over time, the remarried subjects displayed more positive outcomes.  相似文献   
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