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61.
The aim of the present study was to characterize the intestinal absorption of retinol and retinyl palmitate in thoracic duct
and bile duct fistulated rats and to investigate the effect of a simultaneously administered lipase inhibitor, tetrahydrolipstatin
(THL). Absorption was determined as lymphatic recovery over a 24-hr period, including an initial 12-hr continuous intraduodenal
infusion of either [11,12-3H]retinol or [11,12-3H]retinyl palmitate given in emulsified glyceryl trioleate or in mixed micellar solution of monoolein and oleic acid. From
micellar dispersion, labeled retinol and retinyl palmitate were recovered in the lymph to 50–60% and both to the same extent.
Administered in emulsified form, labeled retinol from fed retinyl palmitate was recovered to 47%, but retinol from fed retinol
to only 18%. THL (10−4 M) in the infusate had no significant effect on the recovery of14C-labeled oleic acid. The recovery of label from emulsified glyceryl tri[1-14C]oleate was significantly decreased at this concentration of THL (76.5% vs 19.6% recovery). When administered in emulsified
form, retinol absorption was not significantly affected by THL at 10−4 M, while retinyl palmitate absorption was very significantly decreased (5.0% compared to 47.8%). In the presence of THL,
retinol absorption from retinyl palmitate in micellar solution was decreased (from 58% to 17%). Most of the retinol in the
lymph extracts (72.2 to 91.3) was present as retinyl ester, regardless of the chemical and physical form of administration.
Furthermore, THL did not induce any change in this pattern. 相似文献
62.
Rinaldo Cervellati Emanuela Greco Stefano Costa Maria Clelia Guerra Ester Speroni 《International Journal of Food Science & Technology》2008,43(10):1866-1870
The antioxidant capacities and the total phenolic content in cocoa liquor directly manufactured chocolate from an artisan manufacturer were measured using different in vitro methods (BR, TEAC, and Folin–Ciocalteu Reagent). These parameters were then compared with those of a chocolate made by a leading manufacturing company producing chocolate and cocoa‐containing products. A statistical analysis of the collected data showed that the antioxidant properties of the artisan‐made chocolate are significantly better than those of the factory‐produced one. These results were ascribed to the fact that all the bioactive components in the cocoa beans are better preserved in the artisan‐made chocolate. 相似文献
63.
Alan George Michael T. Heath Joseph Liu Esmond Ng 《International journal of parallel programming》1986,15(4):309-325
Algorithms and software for solving sparse symmetric positive definite systems on serial computers have reached a high state of development. In this paper, we present algorithms for performing sparse Cholesky factorization and sparse triangular solutions on a shared-memory multiprocessor computer, along with some numerical experiments demonstrating their performance on a Sequent Balance 8000 system.Research was supported by the Applied Mathematical Sciences Research Program of the Office of Energy Research, U.S. Department of Energy under contract DE-AC05-84OR21400 with Martin Marieta Energy Systems, Inc., by the U.S. Air Force Office of Scientific Research under contract AFOSR-ISSA-85-00083 and by the Canadian Natural Sciences and Engineering Research Council under grants A8111 and A5509. 相似文献
64.
65.
Ruihua Li David Furniss Heath Bagshaw Angela B. Seddon 《Journal of the American Ceramic Society》1998,81(12):3353-3356
Gallium–sodium–sulfide glasses have been shown to be the most promising host for the 1.3 μm fiber optic amplifier so far. However, the current study has revealed that the formation of stable glasses in this system relies on the existence of a certain amount of oxide in the composition. A glass-forming region was identified when 3 mol% Ga2 O3 was introduced into the melts. Both bulk crystallization and surface crystallization can take place in this system. The thermal behavior of the glasses obtained was studied by DTA and characteristic infrared and UV/visible transmission spectra are presented. The current results are discussed and compared with those previously reported. 相似文献
66.
Transmit selection in spatial multiplexing systems 总被引:3,自引:0,他引:3
In this letter we solve the transmit antenna selection problem for a zero forcing spatial multiplexing system with knowledge of the channel statistics at the transmitter. We show through Wishart matrix analysis that the signal-to-noise ratio on the kth stream is a weighted Chi-squared variable with the weight equal to-the kth diagonal entry of the inverted transmit correlation matrix. We use this result to develop selection algorithms for two cases-maximizing ergodic capacity and minimizing the average probability of error. Monte Carlo simulations illustrate potential performance improvements. 相似文献
67.
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69.
Jeyasankar Alagarmalai David Nestel Daniela Dragushich Ester Nemny-Lavy Leonid Anshelevich Anat Zada Victoria Soroker 《Journal of chemical ecology》2009,35(5):542-551
The Ethiopian fruit fly, Dacus ciliatus, is an oligophagous pest of cucurbit crops, particularly melons, cucumbers, and marrows (summer squash). The present study
aimed to identify host attractants for D. ciliatus and was guided by a behavioral bioassay and an electrophysiological assay. We tested volatile compounds from the fruits of
a host plant, ripe and unripe Galia melon, Cucumis melo var. reticulates. Both sexes were attracted to melon volatiles. Those of ripe melon were preferred. Gas chromatography-electroantennographic
detection analysis of the behaviorally active ripe melon volatiles consistently showed that 14 compounds elicited similar
antennal responses from both sexes. Twelve compounds were identified by gas chromatography-mass spectrometry (GC-MS) using
GC-MS libraries, retention indices (RI), and authentic standards. The electrophysiological activities of the compounds that
were present at sufficient levels for identification, benzyl acetate, hexanyl acetate, (Z)-3-hexenyl acetate, (Z)-3-octenyl acetate, octanyl acetate, (Z)-3-decenyl acetate, and (E)-β-farnesene, were evaluated at six different dosage levels by using electroantennography (EAG). Benzyl and hexanyl acetates
elicited dose responses only in males, while other tested compounds elicited dose responses in both sexes. The strongest responses
were observed for doses between 100 ng and 10 μg. The dose response, in terms of attractiveness to synthetic compounds within
the active range (as determined by EAG), also was evaluated in the behavioral bioassay. Synthetic acetates were attractive
to both sexes when tested individually. Significant attraction was observed when individual compounds were applied in the
bioassay arena at doses of 0.5–1 μg/dispenser. Blends of compounds in equal proportions also were attractive to the insects.
The most attractive blend was a mixture of four or five identified acetates. The addition of an equal proportion of (E)-β-farnesene to this mixture had a deterrent effect. 相似文献
70.
Ana Miklavčič Vekoslava Stibilj Ester Heath Tomaž Polak Janja Snoj Tratnik Janez Klavž Darja Mazej Milena Horvat 《Food chemistry》2011
In order to contribute to the general understanding of the risks and benefits of consuming fish and fish products, total mercury (THg), monomethylmercury (MeHg), polychlorinated biphenyls (PCBs), selenium (Se), n-3 and n-6 fatty acids were determined in fresh and canned fish on the Slovenian market. Furthermore, the mercury exposure of pregnant women in Slovenia was assessed by determining total mercury (THg) in hair, and through fresh and canned fish consumption obtained by a food frequency questionnaire. Based on the frequency of fish consumption and levels of MeHg, THg and PCBs determined in the present study, it can be concluded that fish available on the Slovenian market do not represent a health risk. It was also confirmed that fish are important sources of selenium and n-3 fatty acids. 相似文献