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This study tried to show the contributory role of ions (cations and anions) to great contrast in the goitre prevalence between Bassa and Jos Local Government Areas, both of Plateau State, Nigeria. In pursuance of this, the concentration of cations (Ca++, Fe++, K+, Mg++, Na+, & Zn++) and anions (C1-, F, I-, & NO-3) in soil and drinking water in the two LGAs were determined and their results compared and correlated with the goitre prevalence of these areas. It was observed that both Bassa and Jos LGAs have very low but similar amounts of iodide ions in their soils. Besides, Bassa LGA contained more ions in both soil and drinking water than Jos LGA. In conclusion, the results appear to suggest that the higher ion contents of both soil and drinking water in Bassa LGA exacerbated the coexisting low iodide condition of the LGA, thus resulting in the higher goitre prevalence found in the LGA. 相似文献
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Tindall C.E. Martin J.P. Morrow D.J. Calvert P.A.J. 《Energy Conversion, IEEE Transaction on》1996,11(3):539-546
The use of small alternators, other than for standby purposes, is increasing and this has focused attention on the reliability and utility of the parameters normally quoted for such machines. Test procedures are described and methods used for parameter estimation discussed, with particular emphasis on the difficulties presented by small brushless machines 相似文献
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C Iribarren DR Jacobs M Sadler AJ Claxton S Sidney 《Canadian Metallurgical Quarterly》1996,27(11):1993-1998
BACKGROUND AND PURPOSE: Epidemiological studies indicate a higher incidence of intracerebral (but not subarachnoid) hemorrhagic stroke among persons with low total serum cholesterol levels. This report further examines the prospective relationship of total serum cholesterol with subsequent intracerebral hemorrhage in a large, well-defined population. METHODS: The cohort included 61756 enrollees in a health plan from the San Francisco-Oakland metropolitan area (46% men, 63% white), aged 40 to 89 years and free of cardiovascular disease at baseline. Sixteen-year incidence of combined nonfatal and fatal intracerebral hemorrhagic stroke (International Classification of Diseases [ICD], 8th revision, code 431, or ICD, 9th revision, codes 431 and 432) was investigated in relation to serum cholesterol measured in multiphasic health checkups made in 1977 through 1985. Intracerebral hemorrhagic events were ascertained using hospital discharge records and as underlying cause of death by the California Mortality Linkage Information System. RESULTS: From 1978 through 1993 (average of 10.7 years), there were 386 events (201 in men, 29% fatal; 185 in women, 42% fatal). By multivariate proportional hazards life-table regression analysis, serum cholesterol level below the sex-specific 10th percentile (< 4.62 mmol/L [178 mg/dL] in men), compared with higher cholesterol level, was associated with a significantly increased risk of intracerebral hemorrhage in men aged 65 years or older (relative risk, 2.7; 95% confidence interval, 1.4 to 5.0). An excess risk was also observed among elderly women at the lowest cholesterol range, but a chance finding could not be ruled out. No relationship was seen among men or women aged 40 to 64, and no statistical interaction of low serum cholesterol with hypertension was found in either sex. CONCLUSIONS: In these data, the association between low serum cholesterol level and intracerebral hemorrhage was confined to elderly men. 相似文献
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DR Hill 《Canadian Metallurgical Quarterly》1993,7(3):503-525
Giardia lamblia is a frequent cause of diarrhea throughout the United States and the world. Advances in basic biology indicate that different strains of Giardia exist, that mammals can be infected with G. lamblia-type organisms, and that secretory IgA is important to host protection. Although water remains the most common mode of transmission of Giardia, there has been an increase in the number of person-to-person cases, especially related to children in day care, as well as an increase in food-borne cases. New antigen detection assays have improved the ability to diagnose Giardia in the stool and make it unlikely that duodenal sampling will be necessary. Metronidazole has become the drug of choice for most cases of giardiasis because of its efficacy, favorable tolerance, and availability. For pregnant women who require treatment, a non-absorbable aminoglycoside, paromomycin, may be tried first and metronidazole used if initial treatment fails. 相似文献
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DR Bevan 《Canadian Metallurgical Quarterly》1997,44(10):1033-1035
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