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151.
152.
Edward T. Pryor Gustave J. Goldmann Michael J. Sheridan Pamela M. White 《Ethnic and racial studies》2013,36(2):214-235
Measuring ethnicity in any society is a challenge. Given world immigration patterns, many countries face a growing dilemma in determining the cultural antecedents of their populations. A further complication is the reality that such determination occurs within the political and nationalistic settings where ethnic‐cultural groups may be potent forces in their own right. As societies mature and evolve, there is an increasing tendency for populations, especially those with many generations of residence in the country, to see themselves as ‘indigenous’ to the society in which they live. Canada is not alone in having to deal with the fluidity of the concept, ‘Canadian’, ‘American’, ‘Australian’, ‘Yugoslav’, and ‘Soviet’ are parallel concepts in other countries of multiple ethnic composition. Using 1991 National Census Test results, the article explores some of the parameters of the indigenous category ‘Canadian’. In particular, the location in Canada and mother tongue of respondents reporting ‘Canadian’ as the ethnic origin of their parents and grandparents or as their own ethnic identity are important indicators for this emerging ethnic category. 相似文献
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154.
Xunjun Xiao Michael R. Ferguson Kelsey E. Magee Pamela D. Hale Yan Wang Mark E. Lowe 《Journal of lipid research》2013,54(2):514-521
Colipase is essential for efficient fat digestion. An arginine-to-cysteine polymorphism at
position 92 of colipase (Arg92Cys) associates with an increased risk for developing type-2 diabetes
through an undefined mechanism. To test our hypothesis that the extra cysteine increases colipase
misfolding, thereby altering its intracellular trafficking and function, we expressed Cys92 colipase
in HEK293T cells. Less Cys92 colipase is secreted and more is retained intracellularly in an
insoluble form compared with Arg92 colipase. Nonreducing gel electrophoresis suggests the folding of
secreted Cys92 colipase differs from Arg92 colipase. Cys92 colipase misfolding does not trigger the
unfolded protein response (UPR) or endoplasmic reticulum (ER) stress. The ability of secreted Cys92
colipase to stimulate pancreatic triglyceride lipase (PTL) is reduced with all substrates tested,
particularly long-chain triglycerides. The reaction of Cys92 colipase with triolein and Intralipid
has a much longer lag time, reflecting decreased ability to anchor PTL on those substrates. Our data
predicts that humans with the Arg92Cys substitution will secrete less functional colipase into the
duodenum and have less efficient fat digestion. Whether inefficient fat digestion or another
property of colipase contributes to the risk for developing diabetes remains to be clarified. 相似文献
155.
Jean-Baptiste Ramond Pamela J. Welz Marla I. Tuffin Stephanie G. Burton Don A. Cowan 《Microbial ecology》2013,66(3):563-570
Agri effluents such as winery or olive mill wastewaters are characterized by high phenolic concentrations. These compounds are highly toxic and generally refractory to biodegradation. Biological sand filters (BSFs) represent inexpensive, environmentally friendly, and sustainable wastewater treatment systems which rely vastly on microbial catabolic processes. Using denaturing gradient gel electrophoresis and terminal-restriction fragment length polymorphism, this study aimed to assess the impact of increasing concentrations of synthetic phenolic-rich wastewater, ranging from 96 mg L?1 gallic acid and 138 mg L?1 vanillin (i.e., a total chemical oxygen demand (COD) of 234 mg L?1) to 2,400 mg L?1 gallic acid and 3,442 mg L?1 vanillin (5,842 mg COD L?1), on bacterial communities and the specific functional diazotrophic community from BSF mesocosms. This amendment procedure instigated efficient BSF phenolic removal, significant modifications of the bacterial communities, and notably led to the selection of a phenolic-resistant and less diverse diazotrophic community. This suggests that bioavailable N is crucial in the functioning of biological treatment processes involving microbial communities, and thus that functional alterations in the bacterial communities in BSFs ensure provision of sufficient bioavailable nitrogen for the degradation of wastewater with a high C/N ratio. 相似文献
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157.
Kevin Anderson Yi Chen Zhi Chen Romyr Dominique Kelli Glenn Yang He Cheryl Janson Kin-Chun Luk Christine Lukacs Ann Polonskaia Qi Qiao Aruna Railkar Pamela Rossman Hongmao Sun Qing Xiang Masha Vilenchik Peter Wovkulich Xiaolei Zhang 《Bioorganic & medicinal chemistry letters》2013,23(24):6610-6615
DYRK1B is a kinase over-expressed in certain cancer cells (including colon, ovarian, pancreatic, etc.). Recent publications have demonstrated inhibition of DYRK1B could be an attractive target for cancer therapy. From a data-mining effort, the team has discovered analogues of pyrido[2,3-d]pyrimidines as potent enantio-selective inhibitors of DYRK1B. Cells treated with a tool compound from this series showed the same cellular effects as down regulation of DYRK1B with siRNA. Such effects are consistent with the proposed mechanism of action. Progress of the SAR study is presented. 相似文献
158.
Lisa Dalla Via Aída N. García-Argáez Arianna Adami Silvia Grancara Pamela Martinis Antonio Toninello Daniela Belli Dell’Amico Luca Labella Simona Samaritani 《Bioorganic & medicinal chemistry》2013,21(22):6965-6972
A convenient synthetic route and the characterization of complexes trans-[PtCl2(L)(PPh3)] (L = Et2NH (2), (PhCH2)2NH (3), (HOCH2CH2)2NH) (4) are reported. The antiproliferative activity was evaluated on three human tumor cell lines. The investigation on the mechanism of action highlighted for the most active complex 4 the capacity to affect mitochondrial functions. In particular, both the induction of the mitochondrial permeability transition phenomenon and an aspecific membrane damage occurred, depending on concentration. 相似文献
159.
AbstractSorption of lead(II) or cadmium(II) ions on humic acid particles (at pH 3.5) yields surface complexes which are sparingly soluble in the pH 3.55 region. Interaction of these species with acetic acid or dilute nitric acid released ASV labile metal species (mainly hydrated metal ion). When the pH was adjusted between 4 and 7, increasing amounts of the metal humate species (and humic acid substrate) dissolved and low levels of ASV labile species were detected. Overnight interaction with an excess of acetate ions (0.01 M) led to higher lability values (attributed to acetate/humate ligand exchange). The percentage of labile metal ion detected in acetate solutions varied with the amount of metal ion initially sorbed (range 100 to 500 mmol g?1). With the lower loadings, the ASV labile levels peaked in the pH 6–7 region (at around 12% of total sorbed cadmium, and 4% of total lead). In alkaline solutions, the percentage of labile Cd fell to about half of the peak value, but with Pb, lability values increased at pH > 8, due possibly to the formation of hydroxy complex species. The ASV lability of the Cd and Pb humates, and their 24 hour lability values (determined using a transfer to cation exchanger technique) has been compared with the behaviour of Cu and Zn humates (using similar conditions). 相似文献
160.