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21.
Herman S D'Souza Geraldine Menezes T Venkatesh 《Indian journal of clinical biochemistry : IJCB》2002,17(1):1-4
Our study aimed at comparing lead and zinc protoporphyrin (ZPP) levels in capillary and venous blood samples in a small population
and to employ an easier method of sample collection for a major screening program in school children in major Indian cities.
An awareness program on lead and its effects was conducted in two different schools. A total of thirty urban school children
from South India, with an age group between 4–12 years consented for dual blood sampling and reported for the study. Venous
and capillary blood samples were obtained simultaneously. Blood lead and zinc protoporphyrin (ZPP) levels were estimated using
ESA Lead Analyzer and Haematofluorometer respectively. A significant correlation between capillary and venous ZPP (r=0.98)
and lead (r=0.99) was observed. Rank sum test showed that there is no statistically significant difference between capillary
and venous ZPP (P=0.891) and lead (P=0.672) values. This pilot study recommends that screening for lead may be done using
capillary blood samples since significant correlation is observed between capillary and venous blood measurements. Obtaining
samples using this mode is a non-invasive, less expensive, quick and easy method in children. Appropriately performed capillary
sampling may be considered as an acceptable alternative to venipuncture for screening of blood for lead poisoning both in
children and adults. 相似文献
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In this three-state study, the authors estimate the magnitudes of achievement gaps between English learner (EL) students and their non-EL peers, while avoiding typical caveats in cross-sectional studies. The authors further compare the observed achievement gaps across three distinct dimensions (content areas, grades, and states) and report patterns of EL–non-EL achievement gaps within and across states. The study findings suggest that linguistic barriers and long-term EL designation may contribute to the observed achievement gaps. The findings further suggest that the differences in the stringency of state reclassification criteria may influence the reported size of the EL and non-EL achievement gaps between states. 相似文献
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