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Participants in the Affective Disorders component of Genetic Analysis Workshop 5 had access to five distributed data sets: 1) 187 families from the Collaborative Depression Study, 2) 202 families ascertained as part of the NIMH Family Studies on Affective Disorders, 3) a compilation of 46 pedigrees informative for X-linked markers, 4) HLA typing on 116 kindreds from the Toronto-Rochester Depression Study, and 5) 81 members of an Old Order Amish pedigree demonstrating linkage to markers on chromosome 11p. These databases are each summarized after a brief account is given of the genetics of the affective disorders and commonly used diagnoses. The emphasis of the Workshop was methodologic, with contributions divided evenly between linkage and nonlinkage applications. Contributions are summarized under four substantive areas: regressive logistic models, segregation and other familial analyses, methodologic considerations in linkage analysis, and the relationship between HLA and affective disorders.  相似文献   
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A self-administered questionnaire was developed to examine two dimensions of staff attitudes: (a) the perceived importance of skills that direct-care workers who are asked to teach their clients, and (b) staff expectations that clients will show improvement in these areas. The relationship between importance/ expectancy ratings and self-reported teaching activity was studied in a sample of 32 direct-care workers at a residential facility for adults with developmental disabilities. In general, direct-care workers reported that they were most frequently engaged in escorting clients, watching and teaching clients during recreational activities, and dealing with client's emotional/behavioral outbursts. Improtance/expectancy ratings were correlated significantly with the education level of respondents, but not with self-reported teaching activity.  相似文献   
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Low concentrations of N-nitrosodimethylamine are metabolized in rodent and human liver by cytochrome P450IIE1, an activity competitively inhibitable by ethanol. In rodents coadministration of ethanol with N-nitrosodimethylamine results in increased tumorigenicity in extrahepatic organs, probably as a result of reduced hepatic clearance. To test this concept in a primate, the effects of ethanol cotreatment on the pharmacokinetics of N-nitrosodimethylamine were measured in male patas monkeys. Ethanol, 1.2 g/kg given p.o. before i.v. N-nitrosodimethylamine (1 mg/kg) or concurrently with an intragastric dose resulted in a 10-50-fold increase in the area under the blood concentration versus time curves and a 4-13-fold increase in mean residence times for N-nitrosodimethylamine. Isopropyl alcohol, 3.2 g/kg 24 h before N-nitrosodimethylamine, also increased these parameters 7-10-fold; this effect was associated with persistence of isopropyl alcohol and its metabolic product acetone, both IIE1 inhibitors, in the blood. While no N-nitrosodimethylamine was detected in expired air, trace amounts were found in urine. Ethanol and isopropyl alcohol pretreatment increased the maximum urinary N-nitrosodimethylamine concentration 15-50-fold and the percentage of the dose excreted in the urine by 100-800-fold. Thus ethanol and isopropyl alcohol greatly increase systemic exposure of extrahepatic organs to N-nitrosodimethylamine in a primate.  相似文献   
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Children with no known prior vitamin A deficiency exhibited a significant decline in their serum retinol levels during the acute phase of measles. This decline in circulating retinol was associated with increased duration of fever, higher hospitalization rates, and decreased antibody titers.  相似文献   
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Nickel(II) acetate (NiAcet), a soluble nickel salt known to be an effective initiator of renal epithelial tumors in adult rats, was studied for possible transplacental carcinogenicity. Pregnant F344/NCr rats were given NiAcet i.p. either once a day on day 17 (90 mumol/kg body wt; group 1) or twice on days 16 and 18 of gestation (45 mumol/kg body wt/day; group 2). Offspring of these rats were further subdivided into groups 1A and B and 2A and B, respectively. Groups 1A and 2A received ordinary tap water while groups 1B and 2B received drinking water containing 500 p.p.m. sodium barbital (NaBB) during weeks 4-85 of age. Renal cortical epithelial and renal pelvic transitional epithelial tumors occurred in male offspring given NiAcet prenatally followed by NaBB postnatally (group 1B, 15 tumors in 8/15 rats; group 2B, 10 tumors in 7/15), but not in male offspring given NiAcet only (0/32) or in controls given prenatal sodium acetate (NaAcet) only (0/15) and rarely in males given NaAcet followed by the promoter NaBB (1/15). No renal tumors occurred in females. Pituitary tumor incidence was significantly higher in offspring of both sexes given NiAcet prenatally (NaAcet controls, 4/31, both sexes combined; group 1A, 14/33, P = 0.012; group 2A, 14/31, P = 0.008). Pituitary tumors appeared much earlier in rats given NiAcet prenatally, with or without postnatal NaBB, and often were malignant by cytologic and histologic criteria including pleomorphism and invasion of adjacent structures, unlike the well-differentiated adenomas that occurred less frequently in untreated rats. These results are the first evidence that Ni(II) is a potent transplacental initiator of epithelial tumors in fetal rat kidney and a complete transplacental carcinogen for rat pituitary.  相似文献   
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Use of cigarette tobacco by large proportions of the population of Middle Eastern countries has been reported; however, little is known about smoking behavior in one of America's fastest growing minorities, the Arab Americans. The purpose of this study was to examine cigarette smoking behavior of 237 randomly selected Arab American adults from a telephone listing in the Detroit area. Participants lived in the geographic Arab American community and identified with a Middle Eastern cultural heritage. Nurses, who spoke both English and Arabic, interviewed one adult family member using the 59-item self-report from the Cardiovascular Risk Factor Survey developed by Rice. Mean age of respondents was 40.4 years, 97 percent had been born in the Middle East, and 67 percent had been living in the United States 15 years or less. Current smokers rate was 38.9 percent, former smokers rate was 11.1 percent, never smokers rate was 50 percent, and the quit ratio (proportion of ever smokers who are former smokers) was 22.2 percent. Fifty-four percent of the current smokers were between 25 and 34 years of age; fewer women than men were former smokers, and the highest proportion of current smokers were Lebanese. Subjects who had smoked for the longest time were the least well educated. Arab Americans in this sample had a higher smoking rate, a lower quitting rate, and a much lower quit ratio when compared with national and State of Michigan data. With the growing numbers of Middle Eastern immigrants, there is potential for a dramatic increase in smoking-related health problems.  相似文献   
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1 The standard drug for the treatment of arsenic poisoning is BAL (dimercaprol). BAL possesses marked side-effects and a low safety ratio, drawbacks which new BAL analogues, DMPS and DMSA, do not possess. 2 The efficacy of three chelating agents, BAL, DMPS and DMSA, has been evaluated as a treatment for systemic organic arsenic poisoning, induced by intravenous dichloro(2-chlorovinyl)arsine (lewisite) administration to rabbits. Equimolar dosing schedules were used based upon realistic doses for the most toxic agent, BAL. 3 It was concluded that all three dimercapto chelating agents provided significant protection against the lethal systemic effects of lewisite, and, under the test conditions reported here, there was no significant difference between them in therapeutic efficacy. 4 The cause of mortality following intravenous lewisite in treated and untreated rabbits was pulmonary damage. 5 It is considered that DMPS and DMSA are worthy of further study as replacements for BAL in the treatment of systemic poisoning by lewisite.  相似文献   
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