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91.
MJ O'Neill JA Lewis HM Noble S Holland C Mansat JE Farthing G Foster D Noble SJ Lane PJ Sidebottom SM Lynn MV Hayes CJ Dix 《Canadian Metallurgical Quarterly》1998,61(11):1328-1331
Methanolic extracts prepared from the leaves of Lantana camara have been found to inhibit human thrombin. An assay, in which thrombin activity is measured as a function of clot formation from fibrinogen, was used to guide the fractionation and purification of five principal active constituents (1-5), which were all characterized as 5,5-trans-fused cyclic lactone-containing euphane triterpenes. 相似文献
92.
OBJECTIVE: To test whether isoenergetic isoenergetically-dense doses of dietary 1-monoglyceride or triglyceride differentially influence appetite and meal-to-meal energy intake in man. DESIGN: Six men and six women were each studied twice in a 2 d protocol. On day 1 (maintenance day) they were fed a medium fat (MF) maintenance diet (MF: 40% fat, 47% carbohydrate and 13% protein by energy) calculated at 1.6 x resting metabolic rate (RMR). On day 2 (manipulation day) at 08.30 h subjects consumed a high-fat breakfast designed to contain 80-85% of RMR, composition 10% protein, 56% fat and 34% carbohydrate by energy, with 65% of energy for fat derived as either 1-monoglyceride or triglyceride. Food and energy intake were monitored at lunch (given at 12.30pm) and throughout the remainder of the day. During this time subjects had ad libitum access to isoenergetic, isoenergetically dense MF (40:47:13) foods (550kJ/100g), until 22.30pm). Subjective hunger and satiety were tracked hourly, during waking hours. RESULTS: There was no significant effect of fat type on food or energy intake at lunch or during the ad libitum period. There was no diet effect on subjective hunger (F(1,10)0.00; P= 0.975) in the inter-meal periods of morning or afternoon, nor during the whole day. Subjects found both diets to be similarly pleasant (F(1,61)0.84;P= 0.364). Men and women responded similarly, except that men ate more on all occasions than women. CONCLUSIONS: This study suggests that when a large dose of l-monoglyceride or triglyceride is incorporated into a breakfast meal, it behaves in a manner that is very similar to triglyceride in terms of the effects on hunger, appetite or feeding behaviour. 相似文献
93.
CE Lewis V George M Fouad V Porter D Bowen N Urban 《Canadian Metallurgical Quarterly》1998,19(5):461-476
The Women's Health Trial:Feasibility Study in Minority Populations (WHT:FSMP) examined the feasibility of recruiting postmenopausal women from a broad range of racial and socioeconomic backgrounds into a primary prevention trial requiring marked reductions in dietary fat. Postmenopausal women aged 50-79 yr who had no history of cardiovascular disease or cancer and who consumed 36% or more total energy from fat qualified to participate. We randomized the women into dietary intervention (60%) or control (40%) groups; we aimed to randomize 750 women in 18 months in each of the three clinical centers. All centers achieved goals for randomization based on ethnicity, and two centers exceeded overall recruitment goals. The greatest source of randomized participants was mass mailing, followed by items in the media, referrals, and community outreach. Recruitment yields were generally similar for the ethnic groups but lower for less-educated participants. The experience of WHT:FSMP indicates that postmenopausal women from the African-American, Hispanic, and non-Hispanic white communities can be recruited into dietary intervention studies for the prevention of disease. 相似文献
94.
Lyndsay A. Cartwright Sue Hayes Douglas C. Tozer Dan Clayton Mary-Ann Burns Dena Lewis Noah Gaetz Namrata Shrestha 《Journal of Great Lakes research》2021,47(2):273-282
Beneficial use impairments (BUIs) under the Great Lakes Water Quality Agreement identify environmental issues requiring remedial action within the Great Lakes Areas of Concern (AOCs). We conducted this study to support the assessment of the wildlife component of BUI 3: degradation of fish and wildlife populations. We compared bird and amphibian (frogs and toads) data from the Toronto and Region Conservation Authority’s Terrestrial Long-term Monitoring Program in the Toronto and Region AOC to an adjacent, but otherwise similar, reference watershed, Duffins Creek. Twelve of 13 targets were met within the AOC for forest bird, wetland bird, meadow bird and amphibian populations based on averages of mean annual values at sites within the AOC that were within two standard deviations of averages at sites in the Duffins Creek reference watershed between 2008 and 2017. Even though wildlife populations within the AOC were within the normal range of variability expected from a reference watershed, they were often at lower levels than within the Duffins Creek reference watershed. In addition, forest bird and amphibian populations were negatively affected by urbanization within the AOC and meadow bird indices declined. We conclude that while wildlife populations within the AOC currently meet targets for BUI 3, they continue to be negatively impacted by numerous stressors that are primarily related to past and ongoing urbanization. Thus, continued restoration of wildlife habitat and protection of existing habitat within the AOC is highly recommended. 相似文献
95.
H. O. Menlove M. M. Fowler E. Garcia M. C. Miller M. A. Paciotti R. R. Ryan S. E. Jones 《Journal of Fusion Energy》1990,9(4):495-506
Experiments using high-efficiency neutron detectors have detected neutron emission from various forms of Pd and Ti metal in pressurized D2 gas cells and D2O electrolysis cells. Four independent neutron detectors based on3He gas tubes were used. Both random neutrons (0.05–0.2 n/s) and time-correlated neutron bursts (10–280 n) of 100-s duration were measured using time-correlation counting techniques. The majority of the neutron burst events occurred at –30°C as the samples were warming up from the liquid nitrogen temperature. 相似文献
96.
The strength and stiffness of perimysial connective tissue isolated from cooked beef muscle 总被引:1,自引:0,他引:1
Thick transverse slices of bovine M. semitendinosus were cooked for 1 h at 50°–90° and then cooled. Perimysial connective tissue was dissected from the cooked meat and subjected to mechanical testing in a small-scale device. The initial ‘toe’ region of the J-shaped load-extension curve was progressively lost with increasing temperature, the curve becoming more nearly linear after cooking at 90°C. These effects are explained on the basis of the progressive straightening out of the crimps from the collagen fibres, the crimps becoming finally lost at approximately 70°C. The final stiffness of the perimysium at greater extensions was unchanged at higher temperatures. Breaking strength increased from raw to cooked at 50°C, thereafter decreasing at cooking temperatures up to 90°C. it is proposed that this technique of testing isolated perimysium gives a valuable means of directly measuring the effects of cooking, or other treatments, on the intrinsic properties of perimysial collagenous material. Quantitative knowledge of these will help to determine its contribution to the overall mechanical properties, and hence eating quality, of cooked meat. 相似文献
97.
Hayward G Lewis JE 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1989,36(3):356-364
A comparison between simulation- and measurement-based characterization is provided for the design of one-dimensional, nonadaptive, inverse filters for ultrasonic applications. Both prefiltering and postfiltering are considered by means of two different filtering strategies performed in the time and frequency domains. The results clearly indicate that theoretical methods can be used successfully, provided that the physical limitations of the simulation process are fully appreciated. In some instances, the simulation-based approach is shown to provide superior results, and the reasons for this are explained. 相似文献
98.
On the analysis of two-dimensional discrete singular systems 总被引:2,自引:0,他引:2
In contrast to 1-D systems, the 2-D systems have no natural notion of causality. An artificial restriction traditionally imposed to allow recursive solution of these systems is that of recursibility. In this paper we study 2-Dsingular systems, taking advantage of the nonoriented or noncausal nature of these systems to provide a solution even if the requirement of recursibility does not hold. It is shown thatnonrecursible masks may be described using singular 2-D systems. The analysis approach relies on thefundamental matrix.Research supported by the US Fulbright Foundation in Greece and NSF Grant ECS-8805932. 相似文献
99.
Rodrigo F. Ortiz-Meoz Liping Wang Rosalie Matico Anna Rutkowska-Klute Martha De la Rosa Sabrina Bedard Robert Midgett Katrin Strohmer Douglas Thomson Cunyu Zhang Makda Mebrahtu Jeffrey Guss Rachel Totoritis Thomas Consler Nino Campobasso David Taylor Tia Lewis Kurt Weaver Marcel Muelbaier John Seal Richard Dunham Wieslaw Kazmierski David Favre Giovanna Bergamini Lisa Shewchuk Alan Rendina Guofeng Zhang 《Chembiochem : a European journal of chemical biology》2021,22(3):516-522
Indoleamine-2,3-dioxygenase 1 (IDO1) is a heme-containing enzyme that catalyzes the rate-limiting step in the kynurenine pathway of tryptophan (TRP) metabolism. As it is an inflammation-induced immunoregulatory enzyme, pharmacological inhibition of IDO1 activity is currently being pursued as a potential therapeutic tool for the treatment of cancer and other disease states. As such, a detailed understanding of the mechanism of action of IDO1 inhibitors with various mechanisms of inhibition is of great interest. Comparison of an apo-form-binding IDO1 inhibitor (GSK5628) to the heme-coordinating compound, epacadostat (Incyte), allows us to explore the details of the apo-binding inhibition of IDO1. Herein, we demonstrate that GSK5628 inhibits IDO1 by competing with heme for binding to a heme-free conformation of the enzyme (apo-IDO1), whereas epacadostat coordinates its binding with the iron atom of the IDO1 heme cofactor. Comparison of these two compounds in cellular systems reveals a long-lasting inhibitory effect of GSK5628, previously undescribed for other known IDO1 inhibitors. Detailed characterization of this apo-binding mechanism for IDO1 inhibition might help design superior inhibitors or could confer a unique competitive advantage over other IDO1 inhibitors vis-à-vis specificity and pharmacokinetic parameters. 相似文献
100.
Yttria (Y2O3) films were prepared at high deposition rates of up to 83 nm/s (300 μm/h) by laser chemical vapor deposition (LCVD) using an Y(dpm)3 precursor. The effects of deposition conditions, mainly total gas pressure and laser power, on morphology, deposition rate and preferred orientation were studied. Plasma was produced around the substrate over a critical laser power resulting in significant increases in deposition temperature and deposition rate. The high deposition rate (300 μm/h) by LCVD was about 100 to 1000 times as high as those by conventional CVD. The morphology of Y2O3 films changed from faceted and columnar structures with high (400) orientation to a columnar structure with high (440) orientation, and finally to a cone-like structure with moderate (440) orientation with increasing total gas pressure (Ptot). 相似文献