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71.
The sweat patch is a new, noninvasive method designed to estimate the ethanol consumption of drinking subjects. It consists of salt-impregnated absorbent pads protected by a plastic chamber with attached water-tight adhesive. The patch reportedly collects transepidermal fluid at a steady rate for up to 10 days. Recent laboratory research has indicated a linear relationship between the concentration of ethanol in transepidermal fluid and mean concentration of ethanol in blood. Levels of ethanol in the sweat patch allowed identification of persons drinking at least 0.5 g of ethanol/kg/day with 100% sensitivity and specificity. The study reported here was conducted to test the field effectiveness of this sweat patch in normal, active research subjects. First, several pretests were conducted to determine the optimal location of the patch on the body and its fluid uptake at various sites. A laboratory experiment using nonalcoholic subjects was conducted to replicate previous work, and methods of measuring ethanol concentration in the patch were refined. A field test of the patch was then carried out. Healthy active volunteers drank a single "moderate" dose of ethanol (0.5 g of ETOH/kg of body weight) and then remained abstinent for the next 3 days. A week later, a "heavy" dose (1.0/kg of body weight) was consumed. Only a trace of ethanol was detected in any of the patches worn in either experiment. The patch did not measure ethanol in the transepidermal fluid under field conditions. Thus, further design modifications and pilot testing are required before the full benefits of this unobtrusive measure of drinking can be realized.  相似文献   
72.
When fishery products shipped in interstate commerce contain an environmental contaminant that presents a potential threat to public health, the Food and Drug Administration (FDA) undertakes appropriate regulatory steps to minimize exposure. These efforts range from seizure of the affected product to formal rule-making to establish a limit. The basic provision of the Food, Drug, and Cosmetic (FD&C) Act by which the agency deals with environmental contaminants in the food supply is section 402(a)(1), which deals with poisonous and deleterious substances. Poisonous and deleterious components are deemed to be "added," even if they are natural constituents of food, if any amount is present through the artifice of man. Furthermore, when the level of a naturally occurring toxin is increased in the food through handling and/or processing, the sum of all of the contaminant is deemed to be "added." Unavoidable environmental contaminants may be controlled and/or regulated under this section by the "may render injurious" standard, whereby the agency must demonstrate that there is a significant possibility that exposure to the contaminant could be injurious to human health. "Action levels" are administrative guidelines or instructions to the agency field units that define the extent of contamination at which the agency may regard food as adulterated. Except for polychlorinated biphenyls, for which there is a tolerance established by regulation, FDA has controlled contaminants in aquatic organisms by using action levels. Under section 406 of the FD&C act, the agency can also establish tolerances for unavoidably added poisonous or deleterious substances. This section allows the agency to consider the extent to which a contaminant is unavoidable in food while it limits exposure to the extent necessary to protect the public health. Section 406 requires that the tolerance be established by assessing several factors, including risk. One of these is the capability of processing technology to prevent, reduce, or otherwise control the level of the contaminant. Another factor is the necessity to avoid the needless removal of large amounts of valuable food from the market. Finally, the available analytical and sampling methods must be capable of measuring the contaminant so as to ensure the enforceability of the tolerance. Although the FDA has no statutory authority over intrastate fishing considerations, such as noncommercial fishing, it does provide advice to local or state authorities. It is the best scientific opinion the agency can give, but it is not enforceable per se. Advice is provided when requested by local and state officials where no guideline or tolerance is available, and is meant to deal with local and/or regional public health concerns.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
73.
Residual curarization in the neonate after Caesarean section   总被引:2,自引:0,他引:2  
The transplacental transfer and the neonatal effects of atracurium 0.3 mg.kg-1 (ED95) were compared with those of d-tubocurarine at the usual clinical dose of 0.3 mg.kg-1 (ED90) in 46 patients undergoing elective Caesarean section. The atracurium group (25 patients) was similar to the d-tubocurarine group (21 patients) as far as age, parity and time intervals between precurarization, induction, skin incision, muscle relaxant administration, hysterotomy and birth. The transplacental transfer of atracurium was lower than that of d-tubocurarine, with a feto-maternal ratio of 9 +/- 3% for atracurium and 12 +/- 5% for d-tubocurarine (P less than 0.05). The transplacental transfer of laudanosine was low at 14 +/- 5%, with blood levels of 0.101 +/- 0.032 microM.L-1 in the umbilical vein. Newborns in the two groups were comparable in terms of Apgar scores at one, five and ten minutes, as well as for NACS scores (neurological and adaptive capacity scoring test) at two and 24 hours after birth. However, at 15 min after birth, only 55% of newborns in whom the mothers received atracurium had a normal NACS score (greater than or equal to 35/40) compared with 83% of newborns in whom the mothers received d-tubocurarine (P less than 0.05). Further analysis of the five variables related to active muscle tone revealed that the modal score for active extension of the neck of newborns from the atracurium group was lower than for newborns from the d-tubocurarine group (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
74.
Brain acetylcholinesterase (AChE) activity was measured in forest songbirds exposed to Ultra Ultra Low Volume (UULV) aerial spraying of fenitrothion in New Brunswick for spruce budworm control. Brain AChE activity was determined in 324 songbirds from the sprayed blocks and 47 from an unsprayed control area, and represented four species. In most cases, more than half of the individuals of any species sampled were diagnosed as exposed (20% inhibition) to the fenitrothion sprays and had a mean percent level of inhibition of 40% or greater, relative to mean control values. The proportion of birds with life-threatening levels of inhibition (50%) was usually less than 20%. The largest proportion of birds with life-threatening inhibition was found after the first 210 g AI/ha spray. The White-throated Sparrow had the highest proportion (25–55%) of individuals with life-threatening inhibition after all sprays. Brain AChE inhibition was greater in exposed birds collected after the first 210 g AI/ha spray than after the second one. Variation among species' responses to the sprays is discussed in relation to habitat and foraging preferences. Several sampling biases which may contribute to underestimation of the impact of fenitrothion spraying on birds are identified.  相似文献   
75.
76.
In this study we investigate reasons why teachers adapt substance use prevention curricula in the nation's middle schools. We hypothesize that these reasons will be most salient in schools with racially and ethnically diverse student populations, for whom teachers may believe it appropriate to tailor their curricula. The study sample comprised a nationally representative sample of lead substance use prevention teachers in the nation's middle schools. Respondents answered questions concerning eight student problems or needs that constituted reasons why they might adapt their prevention lessons. Controlling for a variety of school and teacher characteristics, we found that teachers in high minority schools were more likely to adapt curricula in response to three of the eight characteristics presented: youth violence, limited English proficiency, and various racial/ethnic or cultural groups. We suggest that curriculum developers make a systematic effort to understand how teachers are adapting their curricula in high minority schools and incorporate these modifications, if found effective, into their curricula.  相似文献   
77.
78.
OBJECTIVE: To investigate the relationship between overweight and obesity, and mental health problems in Australian 4- to 5-year-old children. METHODS: The study used data from wave 1 (2004) of the Longitudinal Study of Australian Children (LSAC). The participants were 4983 4- to 5-year-old children (2537 boys and 2446 girls) with a mean age of 56.9 months (standard deviation 2.6 months; range 51-67 months). Children were classified as nonoverweight, overweight, and obese on the basis of International Obesity Task Force definitions. Mental health problems were assessed by the Strengths and Difficulties Questionnaire (SDQ) completed by parents and teachers. RESULTS: Although obese 4- to 5-year-old boys had more mental health problems than nonoverweight boys, differences between the groups were small and substantially reduced when analyses controlled for children's sociodemographic characteristics. Parents reported that overweight/obese girls had more peer problems, whereas teachers reported they had more conduct problems. Children in all weight groups had mean scores within the normal range of scores on all the SDQ subscales. CONCLUSIONS: Differences in rates of mental health problems experienced by young children of different weight status appear relatively small. Higher rates of mental health problems experienced by more obese boys may reflect differences in their sociodemographic characteristics rather than their weight status per se. Policies that reduce the number of young children living in poverty or experiencing other adverse social circumstances have the potential to reduce rates of mental health problems experienced by older children with overweight/obesity.  相似文献   
79.
80.
Overall progress in life expectancy (LE) depends increasingly on survival in older ages. The birth cohorts now reaching old age have experienced considerable educational expansion, which is a driving force for the social change and social inequality. Thus, this study examines changes in old age LE by educational attainment in the Nordic countries and aims to find out to what extent the change in national LEs is attributable to education-specific mortality and the shifting educational composition. We used national register data comprising total 65 + populations in Denmark, Finland, Norway and Sweden to create period life tables stratified by five-year age groups (65–90 +), sex and educational attainment. Difference in LE between 2001 and 2015 was decomposed into the contributions of mortality changes within each educational group and changes in educational composition. Increasing LE at all ages and in all educational groups coincided with persistent and growing educational inequalities in all countries. Most of the gains in LE at age 65 could be attributed to decreased mortality (63–90%), especially among those with low education, the largest educational group in most countries. The proportion of the increase in LE attributable to improved education was 10–37%, with the highest contributions recorded for women in Norway and Sweden. The rising educational levels in the Nordic countries still carry potential for further gains in national LEs. However, the educational expansion has contributed to uneven gains in LE between education groups, which poses a risk for the future increase of inequalities in LE.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00698-y.  相似文献   
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