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191.
192.
Free nerve endings are key structures in sensory transduction of noxious stimuli. In spite of this, little is known about their functional organization. Transient receptor potential (TRP) channels have emerged as key molecular identities in the sensory transduction of pain-producing stimuli, yet the vast majority of our knowledge about sensory TRP channel function is limited to data obtained from in vitro models which do not necessarily reflect physiological conditions. In recent years, the development of novel optical methods such as genetically encoded calcium indicators and photo-modulation of ion channel activity by pharmacological tools has provided an invaluable opportunity to directly assess nociceptive TRP channel function at the nerve terminal.  相似文献   
193.
A selective procedure for the extraction of α‐galactosides has been employed in two sweet lupin seeds (Lupinus angustifolius var. Troll and var. Emir) in order to reduce flatulence‐causing factors. Different nutritional parameters (proteins, fat, ash, dietary fibre, starch, sucrose, vitamins B1, B2, E and C) and antinutritional factors (α‐galactosides, trypsin inhibitor activity and inositol phosphates) were studied in raw and processed seeds. The α‐galactoside content in both varieties was reduced by 87–100%. The extracted lupins seeds presented a high retention in protein and fat (109–136% and 95–104%, respectively). Sucrose and soluble dietary fibre, however, decreased significantly as a result of processing and retentions ranged between 5 and 29%. The vitamin B1, B2, and E contents decreased during selective extraction, the retentions being in the ranges 25–47%, 38–40%, and 48–54%, respectively, for var. Troll and Emir. However extracted lupin seeds still contained important amounts of vitamins and insoluble dietary fibre, compounds with nutritional importance. Raw and processed lupins did not contain starch. TIA and vitamin C were not detected, and total inositol phosphates were modified slightly after extraction. In conclusion, the lupin seeds obtained by the extraction of α‐galactosides can be an adequate proteic ingredient to be incorporated in functional foods. Copyright © 2005 Society of Chemical Industry  相似文献   
194.
195.
Antioxidant capacity of 5 DAS (days after seeding) lupin sprouts germinated in the presence of selenate or selenite was determined by cyclic voltammetry (CV), Folin-Ciocalteu reagent (FCR) application and photochemiluminescence (PCL) methods. The hydrophilic (80% methanol) and lipophillic (hexane/methanol) extracts of 5 DAS lupin sprouts germinated in the absence of selenium (control sprouts) showed higher antioxidant capacity than ungerminated seeds. Five DAS sprouts produced in the presence of higher concentration of selenate or selenite (6–8 mg/L) showed increased total antioxidant capacity formed by both hydrophilic and lipohillic antioxidants when evaluated by CV and FCR methods. The hydrophilic extracts from sprouts produced in the presence of low concentration of selenate (2–6 mg/L) showed a significantly higher antioxidant capacity of water-soluble compounds (PCL ACW) while no changes were noted in those germinated in the presence of the highest concentration in relation to the control sprouts. In contrast, the antioxidant capacity of lipid-soluble compounds (PCL ACL) lowered significantly in relation to the control sprouts. The similar changes in antioxidant capacity of sprouts produced in the presence of selenite were found by both PCL assays. Comparison of PCL with CV and FCR reducing capacity assays has shown that these methods yielded considerably different chemical information. Moreover, the changes in total antioxidant and total reducing capacity of sprouts germinated in the presence of either selenate or selenite provided by CV and FCR assays were higher than those obtained by photochemiluminesce measurements. It can be suggested to use 6–8 mg/L of selenite rather than selenate in order to obtain a lupin sprouts with high antioxidant capacity.  相似文献   
196.
Much research on cognitive competence in normal older adults has documented age and sex differences. The authors used new cross-sectional data from the Victoria Longitudinal Study (VLS) (n = 386; age 61 to 95 years) to examine how health and biological age influence age and sex differences in cognitive aging. The authors found evidence for both moderating and mediating influences. Age differences were moderated by health status, such that the negative effects of age were most pronounced among participants of relatively better health. Sex differences were moderated by health and were more pronounced among participants reporting comparatively poorer health. Although health mediated a notable amount of age-related cognitive variation, BioAge mediated considerably more variance, even after statistical control for differences in health. A complex pattern emerged for the mediation of sex differences: Although BioAge accounted for sex-related variation in cognitive performance, health operated to suppress these differences. Overall, both health and BioAge predicted cognitive variation independently of chronological age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
197.
The introduction of salmonids in Patagonia has resulted in significant impacts on its lakes, as well as a major impact on streams, in which native fishes seem to have been displaced almost completely by rainbow trout (Oncorhynchus mykiss). Another perspective is that the introduced salmonid species have resulted in wild fish populations that sustain an economically important sport fishery. The wide distribution and high abundance of escaped farmed rainbow trout, and a clear decrease in the abundance of native and successfully introduced salmonid species in Alicura Reservoir were all observed, based on comparison of recent data and data from 1993 to 1995 corresponding to littoral gillnet captures. Thus, both native fish and introduced salmonid populations seem to have been drastically reduced in the presence of farmed fish escapees. The results of the present study regarding fish escapes deserve major consideration when making decisions about fish cage culture activities for other Patagonian reservoirs.  相似文献   
198.
In this work the efficiency of five allocation rules of irrigation water is analyzed and compared. We define the most efficient rule as the one that minimizes the economic losses arising from a reduction in water availability. The first allocation rule is an equal quota granted to all irrigators. The second one is based on proportional reductions. By means of the third rule all losses of income per hectare are matched, while the fourth makes that all relative losses to the reference incomes are matched. Lastly the fifth rule seeks to maximize private benefit and economic efficiency. We prove that this one would likely be preferred by farmers growing more than one crop. The fundamentals of these rules are included, showing the analytical deduction of the crop-specific reallocations from any prescribed water reduction rule within an irrigation district, as well as the losses of income ensuing from reduced water deliveries. The methodology used herein to compare the efficiency of all these rules is dependent on the relations between allocations and yields. To estimate them, a simple and practical procedure is presented. The five allocation rules are applied to an irrigation community and compared to each other in terms of economic efficiency. Differences in economic losses arising from one rule or another will be sharper the more heterogeneous communities are. Different losses across rules will also be related to the level of water shortage.  相似文献   
199.
This paper reports data on the effect of a new antioxidant, U-83836E, on the lipid peroxidation and antioxidant status of liver, red blood cells (RBCs) and blood serum of rats intoxicated with methanol (3.0 g/kg body weight). Methanol administration slightly increased the levels of peroxidation products in the liver, and markedly increased them in RBCs and serum. In contrast, glutathione-peroxidase, glutathione-reductase activity, reduced glutathione concentration and total antioxidant status were decreased. The use of U-83836E, containing a trolox ring, appeared to be beneficial in reducing lipid peroxidation products and in partially in preventing the decrease in glutathione and antioxidant enzymes induced by methanol in liver and serum. These results show that antioxidant U-83836E may partially prevent methanol toxicity.  相似文献   
200.
 Pea flour from green and yellow mature pea seeds (Pisum sativum) was processed by adding emulsifiers (Glycerol-monostearate GMS, and Amidan 250B polar type monoglyceride, A250). Doughs obtained were cooked for 15 min and 30 min in order to investigate the effect of the presence of emulsifiers and cooking treatment. The quality of macaroni was examined, cooking properties were defined and sensory assessment established. Changes in protein structure were studied by solution fractioning and SDS-PAGE. Modification of the monosaccharide, disaccharide and α-galactoside contents and trypsin inhibitor activity (TIA) were also studied. The addition of emulsifiers improved dough quality. Emulsifiers fundamentally change the solubility of protein fractions, and they were able to promote the soluble fraction molecular weight distribution and the infiltration of low molecular weight fractions into the protein network. The soluble carbohydrate content was not modified by the addition of emulsifiers whilst cooking time affected its content. α-Galactoside content and TIA were reduced after the addition of emulsifiers and the cooking of peas. Received: 2 November 1995/Revised version: 12 February 1996  相似文献   
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