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441.
Echinococcus granulosus is an important zoonotic infection of dogs. The purpose of the present study assessed the performance of two laboratory diagnostic methods with arecoline purgation and necropsy in infected dogs. In total 65 dogs were successfully experimentally infected with protoscoleces of E. granulosus from ovine infection. At 14-34 days post-infection groups of dogs were purged with arecoline hydrobromide and then necropsied. Faecal samples were tested at weekly intervals by coproantigen ELISA and coproPCR. The necropsy infection rate with E. granulosus was 89.2 per cent. Only 43 per cent of dogs were successfully purged after one arecoline dose; this percentage increased to 76.9% for two doses of arecoline purgation. E. granulosus coproantigen was detected by coproELISA in 82.8% of faeces. The positive and negative predictive values for coproantigen ELISA were 96 and 44.4% respectively. E. granulosus DNA was detected in pre-patent faecal samples by coproPCR in 25.9% of dogs. These results indicate that coproELISA is more sensitive than arecoline purgation for the detection of pre-patent E. granulosus infection in dogs. CoproPCR detected E. granulosus DNA in dog faeces by 21 days post-infection before egg production. 相似文献
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Claire Freeman Anita Latai Niusulu Christina Ergler Michelle Schaaf Tuiloma Susana Taua'a Helen Tanielu 《Asia Pacific viewpoint》2023,64(3):390-407
Children's voices have been little heard in the Pacific research. The United Nations Convention on the Rights of the Child 1989 asserts the child's right to have a say on matters that affect them and for their views to be considered. There has been massive growth in technologically assisted participative research; however, we argue the value of hand drawn maps should not be underestimated in the rush to engage with more advanced techniques. We present data from 267 neighbourhood maps drawn by children in Fiji, Kiribati, Samoa and New Zealand. To better understand the social construction of knowledge in children's everyday lives, we propose two models to conceptualise the complexity of their world, a social connection and a spatial connection model. These models reveal how Pacific Island children negotiate different levels of social connection from home, family, and community through to transnational kinship relations. People, specifically family, provide the geographic basis on which their spatial encounters are overlaid. Irrespective of country or rural/urban/atoll setting, it is social space that is the strongest connector for children as displayed in their maps. Application of our models can be used to reveal how knowledge is socially constructed in Pacific children's everyday lives. 相似文献
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Maria Vanessa Baria‐Rodriguez Dexter W. dela Cruz Romeo M. Dizon Helen T. Yap Ronald D. Villanueva 《水产资源保护:海洋与淡水生态系统》2019,29(6):891-900
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449.
Puroindoline (pin) preparations made from flours of hard and soft wheats contained a mixture of pin‐a, 0.19/0.53 α‐amylase inhibitor, and purothionins. Starch granule preparations from the same cultivars were treated with proteinase to remove surface proteins and incubated with solutions of the pin preparations. Binding of pin‐a and purothionins but not the 0.19/0.53 inhibitor was observed with no apparent differences between the behavior of the pin preparations or starch granule preparations from hard or soft types. No binding was observed when several other proteins (bovine serum albumin, total albumins, a commercial preparation of wheat α‐amylase inhibitors, and barley β‐amylase) were incubated with the starch granules under the same conditions, indicating that in vitro binding can be used to study specific starch granule and protein interactions. 相似文献
450.
An in vitro method for preparative‐scale production of artificial glutenin polymers utilizes a controlled environment for the oxidation of glutenin subunits (GS) isolated from wheat flour to achieve high polymerization efficiency. The functionality of in vitro polymers was tested in a 2‐g model dough system and was related to the treatment of the proteins before, during, and after in vitro polymerization. When added as the only polymeric component in a reconstituted model dough (built up from gliadin, water solubles, and starch fractions), in vitro polymers could mimic the behavior of native glutenin, demonstrating properties of dough development and breakdown. Manipulating the high molecular weight (HMW)‐GS to a low molecular weight (LMW)‐GS ratio altered the molecular weight distribution of in vitro polymers. In functional studies using the 2‐g mixograph, simple doughs built up from homopolymers of HMW‐GS were stronger than those using homopolymers of LMW‐GS. These differences may be accounted for, at least in part, by different polymer size distributions. The ability to control the size and composition of glutenin polymers shows the potential of this approach for investigating the effects of glutenin polymer size on dough function and flour end‐use quality. 相似文献