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61.
In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment.  相似文献   
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大丁草中抗菌活性成分的研究Ⅳ   总被引:1,自引:0,他引:1  
谷黎红  李铣  阎四清  朱廷儒 《药学学报》1989,24(10):744-748
从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。  相似文献   
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Abstract: Unusual skin lesions were present at birth in four infants with Turner syndrome. The skin changes in these patients appear to have resulted either from in utero entrapment or pinching of edematous skin or from redundant skin remaining after in utero resolution of lymphedema. Distention by lymphedema is thought to cause several of the phenotypic characteristics seen in patients with Turner syndrome, including nuchal webbing and nail changes. In three of these patients the clinical appearance of the skin changes was similar to cutis verticis gyrata, marked by fixed thickened plaques in folds.  相似文献   
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Juvenile colloid milium is extremely rare, has its onset before puberty, may be inherited, may be caused by ultraviolet light, and is thought to result from the degeneration of keratinocytes. We report a 7-year-old girl with juvenile colloid milium. To the best of our knowledge this is the first reported case in Turkey.  相似文献   
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OBJECTIVE: To determine the prevalence and age of onset of common risky behaviors such as smoking and sexual activity in teens with cystic fibrosis and those with sickle cell disease and to compare their behaviors with those of adolescents in the general population. DESIGN: Survey. SETTING: All five major pediatric tertiary care centers in North Carolina (study participants with sickle cell disease or cystic fibrosis) and North Carolina public schools (comparison population). PARTICIPANTS: Three hundred twenty-one adolescents with cystic fibrosis or sickle cell disease aged 12 to 19 years (mean age, 15.6 years; 49% female). Demographically matched comparison teens for each group were selected from 2760 in-school adolescents (mean age, 16.0 years; 51% female). MAIN OUTCOMES MEASURES: Prevalence of tobacco and marijuana use, alcohol use, sexual intercourse, sexually transmitted diseases, seat belt use, weapon carrying, and age of onset of these behaviors. RESULTS: Chronically ill teens reported significantly less lifetime and current use of tobacco, marijuana, and alcohol; less sexual intercourse; less weapon carrying, less drunk driving, and more seat belt use than their peers. Nonetheless, 21% of the teens with cystic fibrosis and 30% of those with sickle cell disease had smoked; sexual intercourse was reported by 28% and 51%, respectively. Age of onset of these behaviors was frequently older for the chronically ill teens. CONCLUSION: Teens with cystic fibrosis or sickle cell disease took more potentially damaging health risks than might be expected, although the prevalence was lower than reported by their peers. Future longitudinal studies should examine the relationships between chronic illness, physical and psychosocial maturation, and risky behavior. Screening for psychosocial issues, including risky behaviors, should be incorporated into the routine health care of chronically ill teens.  相似文献   
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