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Sera from randomly selected 49 professional blood donors, 617 pregnant women, 14 butchers, 528 slaughtered goats and 24 domestic cats in the district of Mymensingh were tested for the presence of T. gondii antibodies using a Latex agglutination test (LAT). Overall 12.4% blood donors, 11.18% pregnant women, 50.00% butchers, 12.88% slaughtered goats and 33.33% cats had diagnostically significant antibody titers (> or = 1:64) to T. gondii. Epidemiological studies on T. gondii infection with LAT were conducted in 25 family members with sero-positive cats and 9 family members with 2 sero-positive women without cats in the family. Significantly (p < 0.01) higher sero-positivity rate was recorded in the family members (24.00%) with positive cats in comparison to family members (11.11%) without cats. The epidemiologic study indicates that infected cats and goat meat might be significant sources of T. gondii infection for humans in Bangladesh. 相似文献
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PR Burchat GJ Feldman T Barklow AM Boyarski DL Burke JM Dorfan L Gladney G Hanson K Hayes RJ Hollebeek WR Innes JA Jaros D Karlen AJ Lankford RR Larsen BW LeClaire NS Lockyer V Lüth C Matteuzzi RA Ong ML Perl B Richter K Riles MC Ross JM Yelton C Zaiser GS Abrams D Amidei AR Baden J Boyer F Butler G Gidal MS Gold G Goldhaber L Golding J Haggerty D Herrup I Juricic JA Kadyk ME Nelson PC Rowson H Schellman WB Schmidke PD Sheldon GH Trilling de la Vaissiere C DR Wood ME Levi T Schaad 《Canadian Metallurgical Quarterly》1987,35(1):27-41
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Conclusions Data on the service life of building materials and components are essential to the cost-effective use of materials. For this
reason, it is important that methods be available for reliably predicting service life. In the current state-of-the-art, test
methods are most often useful for comparing the relative ‘durabilities’ of building materials as opposed to predicting quantitatively
the service life.
The need to advance the state-of-the-art of service life prediction of building materials has stimulated considerable interest
in national and international activities in recent years. The technical barriers to meeting the need for improved predictions
are numerous and formidable. Therefore, it is not practicable for one laboratory or even one country to pursue, on its own,
the long-term, complex and costly research needed to address the barriers. But the barriers offer the opportunity for continued
and increased international interactions and the opportunity for performing challenging research on building materials and
their degradation processes. In this way, the needs can be met. 相似文献
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The effects of heat-induced interactions between milk fat globule membrane components and skim milk proteins in whole milk on the structure of the membrane were examined by isopycnic sucrose density gradient centrifugation and by using Triton X-100 as a membrane probe. Skim milk components were incorporated into all the lipoprotein fractions separated by density gradient centrifugation. High density complexes, higher in density than those found in the natural milk fat globule membrane, were formed during the heat treatment. Losses of natural membrane polypeptides from the medium and low density lipoproteins were observed on heating. Heating whole milk also altered the rate of release of membrane components by detergent, with decreases in protein released and an increase in phospholipid constituents released. Studies on washed cream indicated that some of the changes in the membrane on heating whole milk occurred due to the heat treatment alone, independent of the interactions with skim milk proteins. 相似文献