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Starch attracts public attention as a replacement of fossil fuel in polymer industries because it is renewable, biodegradable and nontoxic. In this study, the isolation of starch from defatted cashew nut shell (CNS) using wet milling was reported. A product that contains 85.01 wt.% starch was recovered from the defatted CNS. Various analyses were performed on the starch to characterize its physicochemical properties. It was found that the starch obtained possesses high amylopectin content (75.35 wt.%), which supports the results of thermal analysis that proved the high crystallinity of starch. Morphological study of the starch showed that bonded resins were found attached to the starch granules. Due to high crystallinity, the presence of bonded resins and low cost, starch from defatted CNS can be considered as a prospective renewable material in polymer industries, with potential to compete with current feedstock such as potato and corn.  相似文献   
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Core peptide (CP) is a unique peptide derived from thetransmembrane sequence of T cell antigen receptor (TCR)-alpha chain and is capable of inhibiting the immuneresponse both in vitro and in animal models of Tcell mediated inflammation. The structure of CP, withsequence GLRILLLKV, is similar to the amphipathic regionof many peptides. Unlike antimicrobial peptides,however, which damage cell membranes, electron microscopyand propidium iodide exclusion assays on cell membranessuggest that CP does not create pores and may act byinterfering with signal transduction at the membranelevel. To investigate this effect further we report theresults of 31P and 2H solid-state NMRspectroscopy of CP on model membranes. As predicted,even at high concentrations of CP, the structure of modelmembranes was not significantly perturbed. Only at thevery high peptide-to-lipid molar ratio of 1:10significant effects on the model membranes were observed. We conclude that CP does not destroy the integrity of thelipid bilayer.  相似文献   
748.
Leaf cuticular membranes can be released cleanly and in one piece after a 10 min treatment of leaf in a 100 C acetolysis mixture: acetic anhydride, 9; and concentrated H2SO4,1 v/v. This method has been used till now only for studying pollen and spore morphology but was found quite appropriate for a taxonomic study of the leaf surface of the genus Pandanus.  相似文献   
749.
Huynh Congly 《CMAJ》1985,132(7):738-739
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Gastrointestinal (GI) homeostasis requires the action of multiple pathways. There is some controversy regarding whether small intestine (SI) Paneth cells (PCs) play a central role in orchestrating crypt architecture and their relationship with Lgr5 + ve stem cells. Nevertheless, we previously showed that germline CSF-1 receptor (Csf1r) knock out (KO) or Csf1 mutation is associated with an absence of mature PC, reduced crypt proliferation and lowered stem cell gene, Lgr5 expression. Here we show the additional loss of CD24, Bmi1 and Olfm4 expression in the KO crypts and a high resolution 3D localization of CSF-1R mainly to PC. The induction of GI-specific Csf1r deletion in young adult mice also led to PC loss over a period of weeks, in accord with the anticipated long life span of PC, changed distribution of proliferating cells and this was with a commensurate loss of Lgr5 and other stem cell marker gene expression. By culturing SI organoids, we further show that the Csf1r?/? defect in PC production is intrinsic to epithelial cells as well as definitively affecting stem cell activity. These results show that CSF-1R directly supports PC maturation and that in turn PCs fashion the intestinal stem cell niche.  相似文献   
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