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Hyperargininemia is a progressive neurometabolic disorder caused by deficiency of hepatic cytosolic arginase I, resulting from mutations in the ARG1 gene. We diagnosed arginase deficiency in a three-year-old male child of first-cousin Palestinian Arab parents. Prenatal diagnosis of an unaffected fetus was achieved in the second trimester of a subsequent pregnancy by cordocentesis and analysis of arginase activity in fetal erythrocytes. ARG1 mutation analysis in the proband revealed homozygosity for a deletion of 10 753 bp extending from the first intron to beyond the poly (A) site of the gene. This is the first gross deletion in the ARG1 gene to be identified and the first mutation to be described in an arginase-deficient patient of this ethnic origin. The identification of the ARG1 deletion in this family enabled first-trimester prenatal diagnosis in a subsequent pregnancy by multiplex PCR analysis performed on chorionic villous DNA. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
104.
I am pleased to offer this treatise on the conveying of particulate solids. In doing so I wish to acknowledge the immense contributions of Trevor Kletz in providing guidance to the chemical process industries in many areas including inherently safer design principles and operating practices.  相似文献   
105.
Summary This technical paper summarizes the various systems currently available for the removal of SOx, NOx and particles from possible acid rain emission sources associated with industrial processes. Preferred systems are outlined in the conclusions.This paper was first presented at the Institution of Environmental Sciences Seminar An Update on Acid Rain which took place in London during November, 1984. Stanley Wallin is a Principal Scientific Officer at Warren Spring Laboratory. He is an engineer working in the environmental field, and his main interests and research are in the measurement and control of pollution from stationary sources. He acts as a consultant for the European Economic Community, the Environmental Protection Agency, and the UK's Health and Safety Executive.  相似文献   
106.
California condor (Gymnogyps californianus) foods and feathers, and turkey vultures (Cathartes aura), common ravens (Corvus corax), and their eggs were collected within the condor range to determine exposure of condors to environmental contaminants. Samples were analyzed for organochlorines and trace elements. Food items contained low concentrations of organochlorines and generally low concentrations of lead. DDE was detected in all vulture carcasses and nearly all raven carcasses at generally moderate concentrations. Other organochlorines occurred infrequently in carcasses and generally at low concentrations. Turkey vulture eggshells were 16% thinner than the pre-DDT mean; there was no change in shell thickness of raven eggs. Vulture eggs contained an average of 6.9 ppm DDE and two contained excessive concentrations of endrin. DDE concentrations were low in raven eggs. Residues of As, Cd, Cr, Cu, Fe, Hg, Ni, Se, Tl, and Zn in tissues of vultures and ravens appeared normal when compared with reference values for other species. Lead concentrations in bone of turkey vultures and feathers of condors appeared to be elevated above normal background concentrations in some cases. Current exposure of condors to organochlorines appears low; however, we are concerned about the excessive exposure of turkey vultures to organochlorines, possibly in Central America. Lead exposure to vultures and condors has occurred, but its significance to their populations is unknown.  相似文献   
107.
The fates of radioactive cadmium, strontium, cesium, cobalt, arsenic, mercury, zinc, and copper spiked into sewage sludge were determined when the sludge was gasified by a process that maximizes production of char from the sludge (ChemChar process). For the most part the metals were retained in the char product in the gasifier. Small, but measurable quantities of arsenic were mobilized by gasification and slightly more than 1% of the arsenic was detected in the effluent gas. Mercury was largely mobilized from the solids in the gasifier, but most of the mercury was retained in a filter composed of char prepared from the sludge. The small amounts of mercury leaving the gasification system were found to be associated with an aerosol product generated during gasification. The metals retained in the char product of gasification were only partially leachable with 50% concentrated nitric acid.  相似文献   
108.
Understanding the processes causing herbicide transport to surface waters is crucial to determine mitigation options to reduce these losses. To this end, we investigated the atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) transport in three agricultural catchments (1.1-2.1 km2) in the watershed of Lake "Greifensee" (Switzerland). In 1999, atrazine application data were recorded for all three catchments. Time proportional samples were taken at a high temporal resolution at the catchment outlets. Extremely wet conditions caused large relative losses from the catchments, ranging between 0.6 and 3.5% of the amount applied. Most of the atrazine load was due to event-driven diffuse losses from the fields. Farmyard runoff contributed less but caused the highest concentrations (up to 31 microg L(-1)) in the brooks. The maximum concentrations due to diffuse losses varied between 1.2 and 8.2 microg L(-1) among the catchments. Despite different absolute concentration levels, the concentration time-series were very similar. It seems that the travel-times within the catchments were mainly controlled by the rainfall pattern with little influence of the catchment properties. These properties, however, caused the relative losses to vary by a factor of 6 between the catchments. This variability could be partly explained by differences in the connectivity of the fields to the brooks and by their hydrological soil properties. A comparison of the losses from the three catchments with those from the entire watershed of Lake Greifensee demonstrated that they were representative for the larger area. Hence, the study results provide a good data set to evaluate distributed models predicting herbicide losses.  相似文献   
109.
ABSTRACT: This study emphasized a field investigation of salt release to overland flow from Mancos shale lands of the Price River Basin, Utah. Although a high degree of natural variation existed in the data, which precluded the separation of factors affecting diffuse salt loading that occurs during overland flow, a simplistic nonpoint source loading function developed on empirical concepts was fit to the data. This function was then used to calculate the average annual salt yield to the Price River by overland flow. It was found that even under severe conditions, the salt yields from Mancos shale lands due to overland flow is relatively minor, accounting for less than 1.5 percent of the average annual salt mass transported from the basin by the Price River.  相似文献   
110.
Populations of introduced European wild boar, feral pigs, and combinations of both types (all Susscrola L.) inhabit thirteen areas in the National Park Service system. All parks have relatively stable populations, with the exception of Great Smoky Mountains National Park, which reported a rapidly expanding wild boar population. Suspected and documented impacts were apparently related to pig densities and sensitivity of the ecosystem; the three largest units with dense wild pig populations reported the most damage. Overall, wild pigs are a relatively minor problem for the Park Service; however, problems are severe in at least three parks, and there is potential for invasion of wild boars into several additional parks in the Appalachian Mountains. More specific information is needed on numbers of wild pigs and their impacts in the various parks.  相似文献   
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