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Twenty-five pregnancies at risk for spinal muscular atrophy I (SMA I) have been monitored by first-trimester prenatal diagnosis. Microsatellite markers were used in all cases to amplify polymorphic regions at the D5S125, D5S435, D5S39, D5S127, and D5S112 loci. All families, including 12 SMA I pedigrees with a deceased index child, were fully informative for DNA analysis. Three fetuses were predicted to be affected and 22 fetuses were predicted to be unaffected. Twenty-two newborns were unaffected by clinical examination at birth. These results support the accuracy of SMA I prenatal diagnosis based on linkage analysis.  相似文献   
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This paper criticises the conclusions and the unanswered questions in the National Institute of Standards and Technology (NIST)'s official report on the evacuation of the World Trade Center in New York City, United States, on 11 September 2001. It reviews the extent to which the report disregards several conventional statistical methods and comments on the NIST's refusal to share the machine‐readable data file with the scientific community for replication and further analysis. Problems lie in the sampling methods employed, the treatment of missing data, the use of ordinary least squares (OLS) with binary dependent variables, the failure to document the scalability of the scales used, the lack of tests to check for constant error variance, and the absence of overall fit tests of the model. There are also conceptual and theoretical issues, such as the absence in the report of considerations of the influence of group‐level processes and their impact on the collective behaviour of evacuating collectivities.  相似文献   
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This study investigates the factors determining an individual's response to official recommended protective measures, based on the Health Belief Model and the Protective Action Decision Model, to understand the adoption of protective behaviour during an H7N9 (Avian Influenza A) emergency. A public survey involving 1,375 respondents was conducted in Anhui Province, China, during the 2013 H7N9 outbreak to test the research model and hypotheses. The results indicate that protective, stakeholder, and risk perceptions influence positively an individual's willingness to take recommended actions. Protective and stakeholder perceptions also have a positive bearing on lay people's risk perceptions. A stakeholder perception is a vital determinant of a protective perception. More importantly, the effects of protective and stakeholder perceptions on behavioural responses to recommendations are mediated in part by risk perception. These findings can help public health officials to develop messages to encourage members of the population to protect themselves effectively during an influenza crisis.  相似文献   
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The main constraints on energy exploration in the Australian arid zone are logistic, with limited additional constraints from Aboriginal reserves. The main consequence is increased access, with possible introduction of weeds and expansion of tourism and cattle grazing in consequence.  相似文献   
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Amiodarone treatment in pregnancy might be difficult to handle because of the long half-life of the drug (14–28 days up to 2 months) and because it reduces maternal and neonatal thyroid activity. Although short-term use in pregnancy has been described in cases of fetal supraventricular tachycardia, there are few reports on the chronic use of the drug. In this paper we describe our experience with amiodarone treatment in two pregnant sisters with familial dilatative cardiomyopathy and ventricular malignant extrasystole. Prolonged administration of amiodarone (400–200 mg/die) since the beginning of pregnancy did not have any adverse effects; maternal and neonatal thyroid function was normal, as was the neurological and motor development of the neonates.  相似文献   
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The removal of copper and cyanide from aqueous solution by activated carbon has been investigated. Using a coal-based activated carbon, initial concentrations of 244 to 2441 mg/litre total cyanide combined with 61 to 610 mg/litre copper were reduced to a minimum of 3.6 mg/litre total cyanide and 0.6 mg/litre copper in the presence of a fixed initial quantity of air.Cyanide removal was, found to be augmented by the presence of copper in solution, and by the supply of additional air.It is suggested that cyanide removal is accomplished by catalytic oxidation on the carbon surfaces, and that additional cyanide is removed in the presence of copper by adsorption of cyano-cuprate complexes onto the activated carbon.  相似文献   
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An electron microscopic DOPA reaction test of fetal skin was used for the prenatal diagnosis of tyrosinase-negative oculocutaneous albinism (OCA). The subject was a 34-year-old Japanese woman in her second pregnancy. Her first child, born in 1982, had been previously examined and confirmed to have tyrosinase-negative OCA. The parents requested a prenatal diagnosis and we sampled skin from the upper trunk of the fetus. On conventional electron microscopy, the development of melanosomes in interfollicular melanocytes had progressed no further than stage II. Fetal skin samples incubated with L-DOPA solution indicated a lack of tyrosinase activity and showed that the melanosomes had not progressed beyond stage II. In skin samples from the trunks of three Japanese fetuses aborted for other reasons at 19–20 weeks of gestation, most premature melanosomes were further melanized to stage IV after incubation with L-DOPA solution. A prenatal diagnosis of tyrosinase-negative OCA was made. The parents requested a termination and skin biopsies of the abortus confirmed the diagnosis. This study shows that tyrosinase is normally present in melanocytes of the fetal epidermis at 20 weeks' gestation, and that the electron microscopic DOPA reaction test of a fetal skin biopsy specimen is safe and practical, and provides reliable information for making a prenatal diagnosis of tyrosinase-negative OCA in the second trimester.  相似文献   
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