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Summary The kinetics of phenobarbital (PB) was compared after oral administration of equivalent doses of the drug as the acid or the propylhexedrine salt (barbexaclone) to 7 normal volunteers. The absorption and elimination parameters were very similar. It was concluded that propylhexedrine did not affect the serum kinetics of PB given as barbexaclone.  相似文献   
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As patterns of family formation change, it is important to know how children's lives are affected by their parents' marital and socioeconomic circumstances. Using data from the 1993 Kenya Demographic and Health Survey, this study shows that children of never married and formerly married mothers have significantly higher probabilities of polio dropout and acute undernutrition than those of monogamously married mothers. The number of male household members of working age greatly enhances the chances of full immunization and the nutritional status of children whose mothers were previously married. For children of never married mothers, the benefits of residing with males of working age are largely a function of ethnicity. The results also show that, although children are not disadvantaged nutritionally when their fathers have more than one wife, polygyny is associated with a higher probability of polio dropout and lower probability of full immunization than monogamy. Higher socioeconomic status is associated with a greater probability of full immunization and a lower probability of malnutrition but socioeconomic factors do not explain the effects of mothers' marital status. The findings underscore the complex realities of family interaction and the importance of the broader social context in accounting for variations in child welfare across diverse marital situations.  相似文献   
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The formulae for some typical epidemiological indices in case-control studies with non-differential misclassification are expressed in terms of two groups (α, β) and (γ, δ) of misclassification probabilities of exposure E and confounder C, respectively, and the initially estimated frequencies. The parameters α and β denote the probability that subjects exposed to E are classified as non-exposed and the probability that non-exposed ones will be classified as exposed, respectively. Similarly, δ and γ stand for the probability that those who have been exposed to C will be classified as non-exposed and the probability that non-exposed subjects are classified as exposed, respectively. The non-negativeness of the expressions for the ‘true’ frequencies in terms of the measured ones and the misclassification probabilities leads to the construction of feasibility regions for α, β, γ and δ. For a number of ‘acceptable’ 4-tuples (α, β, γ, δ), all of which lie inside these feasibility regions, a sequence of feasible values for an epidemiological index is determined, after employing a systematic procedure by means of a ‘searching net’ with increments Δα, Δβ, Δγ, Δδ. The procedure serves to determine the characteristics of the (experimental) cumulative distribution function for any selected epidemiological index. The final stage in exploiting the structure of feasibility regions for α, β, γ and δ is to use the cumulative distribution function to calculate quantiles for the index associated with prescribed probabilities.  相似文献   
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OBJECTIVES: Measurement of cortical thickness and subjective assessment of cortical porosity on panoramic radiographs are methods previously reported for diagnosing osteoporosis. The aims of this study were to determine the relative efficacy of the mandibular cortical index and cortical width in detecting osteoporosis, both alone and in combination, and to determine the optimal cortical width threshold for referral for additional osteoporosis investigation. STUDY DESIGN: Six hundred seventy-one postmenopausal women 45 to 70 years of age were recruited for this study. They received dual energy x-ray absorptiometry (DXA) scans of the left hip and lumbar spine (L1 to L4), and dental panoramic radiographic examinations of the teeth and jaws. Three observers separately assessed the mandibular cortical width and porosity in the mental foramen region of the mandible. Cortical width was corrected for magnification errors. Chi-squared automatic interaction detection analysis (CHAID) software was used (SPSS AnswerTree, version 3.1, SPSS Inc., Chicago, IL). RESULTS: Chi-squared automatic interaction detection analysis showed that the cortical porosity was a poorer predictor of osteoporosis than mandibular cortical width. For the 3 observers, a mandibular cortical width of <3 mm provided diagnostic odds ratios of 6.51, 6.09, and 8.04. The test is therefore only recommended in triage screening of individuals by using radiographs made for purposes other than osteoporosis. CONCLUSION: When evaluating panoramic radiographs, only those patients with the thinnest mandibular cortices (i.e., <3 mm) should be referred for further osteoporosis investigation.  相似文献   
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The variability of blood pressure measured by oscillometry and the validity of this technique were studied in premature infants. Thirty premature babies whose postnatal age was six days or more had their blood pressure measured 11 times over a twenty-minute period for three consecutive days. Movements were found to have a very substantial influence on results that could not be reliably compared with values obtained invasively. No consistent pattern of variations of oscillometric results obtained during the eleven measurements of use for recommending a specific measurement time was found. Diastolic blood pressure fell gradually over the three-day study period. The most reliable of the eleven daily values was the lowest value for which good correlations were found between the three study days; this lowest value was not influenced by neonatal or postnatal factors.  相似文献   
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Ruggieri  M.  Iannetti  P.  Polizzi  A.  Pavone  L.  Grimaldi  L. M. E. 《Neurological sciences》2004,25(4):s326-s335
Neurological Sciences - Despite the consistent amount of information accumulated in recent years on multiple sclerosis (MS) in childhood, many clinicians still view this condition as an exclusively...  相似文献   
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