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Williamson Kathleen A.; Hever Ann M.; Rainger Joe; Rogers R. Curtis; Magee Alex; Fiedler Zdenek; Keng Wee Teik; Sharkey Freddie H.; McGill Niolette; Hill Clare J.; Schneider Adele; Messina Mario; Turnpenny Peter D.; Fantes Judy A.; van Heyningen Veronica; FitzPatrick David R. 《Human molecular genetics》2006,15(12):2030
Table 1 相似文献
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Larry E. Davis Mario Kornfeld Herbert S. Mooney Kurt J. Fiedler Kathleen Y. Haaland William W. Orrison Elsa Cernichiari Thomas W. Clarkson 《Annals of neurology》1994,35(6):680-688
For 3 months in 1969 a family in the United States that included a pregnant mother consumed pork containing methylmercury. Children, aged 20, 13, and 8 years and a neonate, developed severe neurological signs. Twenty-two years later, the 2 oldest had cortical blindness or constricted visual fields, diminished hand proprioception, choreoathetosis, and atentional deficits. Magnetic resonance images showed tissue loss in the calcarine and parietal cortices and cerebellar folia. The youngest had quadriplegia, blindness, and severe mental retradation until their deaths. The brain of the 8-year-old who died at age 30 showed cortical atrophy, neuronal loss, and gliosis, most pronounced in the paracentral and parietooccipital regions. The total mercury level in formalin-fixed, left occipital cortex was 1,974 ng/gm as measured by atomic absorption. Regional brain mercury levels correlated with extent of brain damage. A control patient had 38.5 ng of mercury/gm in the occipital cortex. Systemic organs in the patient and a control subject had comparable mercury levels. In mercury-intoxicated rats, we found that only 5 to 10% of total brain mercury was lost by formalin fixation. Brain inorganic mercury in the patient ranged from 82 to 100%. Since inorganic mercury crosses the blood-brain barrier poorly, biotransformation of methyl to inorganic mercury may have occurred after methylmercury crossed the blood-brain barrier, accounting for its persistence in brain and causing part of the brain damage. 相似文献
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Mortality of a municipal-worker cohort: IV. Fire fighters 总被引:3,自引:0,他引:3
Morbidity and mortality studies of fire fighters have produced varied and inconsistent findings regarding the potential chronic effects of fire fighting including respiratory disease, cardiovascular disease, and cancer. The mortality experience of 1,867 white male fire fighters who were employed for the City of Buffalo a minimum of five years with at least one year as a fire fighter was studied. Vital status was determined for 99% of the cohort, resulting in 470 observed deaths. The fire fighter cohort was characteristic of a healthy worker population. All-cause mortality was close to the expected standardized mortality ratio (SMR) = 95, and significantly lower than expected mortality was seen for all external causes (SMR = 67)--in particular, for suicide (SMR = 21) and respiratory diseases (SMR = 48). Significantly elevated SMRs were found for benign neoplasms (SMR = 417), cancer of the colon (SMR = 183), and cancer of the bladder (SMR = 286). Cause-specific mortality is presented by number of years employed, calendar year of death, year of hire, and latency. Cancer mortality was significantly higher in the long-term fire fighters, and risk of mortality from all malignant neoplasms tended to increase with increasing latency. Patterns in risk of mortality among fire fighters for cancers of the bladder, colon, and brain are intriguing. Additional follow-up of this cohort and initiation of cancer morbidity studies would be helpful in further clarifying the potential long-term effects of fire fighting on cancer risk. 相似文献
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Metabolic products of microorganisms. 255. Nikkomycins Wz and Wx, new chitin synthetase inhibitors from Streptomyces tendae 总被引:3,自引:0,他引:3
H Decker F Walz C Bormann H Z?hner H P Fiedler H Heitsch W A K?nig 《The Journal of antibiotics》1990,43(1):43-48
Two new dipeptidyl nikkomycins of the Z and X type were isolated from the culture broth of Streptomyces tendae TU 901/395-11/32 and characterized. They show a variation in the amino acid moiety of the molecule. Nikkomycin Wz is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to uracil, whereas nikkomycin Wx is composed of L-tyrosine and 5-amino-5-deoxy-D-allo-furanuronic acid N-glycosidally bound to 4-formyl-4-imidazolin-2-one. The new nikkomycins are good inhibitors of chitin synthetase from Coprinus cinereus but they did not inhibit growth of fungi and yeasts. 相似文献
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V J Pisciotta X Wu J A Fiedler C F Serago M L Calish-Watzich J G Schwade P V Houdek 《Medical physics》1992,19(6):1451-1453
Assessment of electron beam energy and its long term stability is part of standard quality assurance practice in radiation oncology. Conventional depth-ionization or depth-film density measurements are time consuming both in terms of data acquisition and analysis. A procedure is described utilizing ionization measurements at two energy specific depths. It is based on a linear relationship between electron beam energy and its practical range. Energy shifts within the range covered by the two measurement depths are easily resolved. Within a range of +/- 0.50 MeV (+/- 1.30 MeV) around the established mean incident energy of 5.48 MeV (20.39 MeV), the method accuracy is better than 0.10 MeV. 相似文献
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The case of a 24-year-old patient is presented who was erroneously presumed to have unilateral testicular aplasia following inguinal exploration in early childhood. At the age of 24 years he underwent surgery for a soft perineal mass, which was found to be perineal testicular ectopia associated with a congenital hernia. Histological examination of the excised testicle revealed atrophy of the germinal epithelium. A survey of the literature yielded approximately 175 more cases of perineal testicular ectopia. This is the most frequent from of testicular ectopia with a relative incidence of less than 1% of all cases of undescended testes. Ectopic testes seem only to differ from undescended testes in terms of topography. Little difference can be observed in terms of histology or the incidence of concomitant hernias. 相似文献
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