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11.
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Preface     
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Explanatory models of sexual aggression were examined among mainland Asian American (n = 222), Hawaiian Asian American (n = 127), and European American men (n = 399). The Malamuth et al. (N. M. Malamuth, D. Linz, C. L. Heavey, G. Barnes, & M. Acker, 1995; N. M. Malamuth, R. J. Sockloskie, M. P. Koss, & J. S. Tanaka, 1991) confluence model of sexual aggression, which posits impersonal sex and hostile masculinity as paths to sexual aggression, was consistently supported. Culture-specific moderators of sexual aggression were also identified. Whereas loss of face was a protective factor against sexual aggression in the Asian American samples, it generally was not a protective factor among European Americans. These findings are not a function of actual or perceived minority status. An implication is that theoretical models may need to be augmented with cultural constructs for optimal application in certain ethnic group contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Active transport of nitrofurantoin across the mammary epithelium in vivo   总被引:1,自引:0,他引:1  
Nitrofurantoin is a commonly used urinary tract antibiotic that has been found at high concentrations in human milk. In vivo studies in rats were carried out to determine the mechanism by which this drug crosses the mammary epithelium. Lactating rats were gavage-fed with nitrofurantoin, and their milk and plasma levels of the antibiotic were measured at intervals up to 8 hr. The average milk-to-plasma (M/P) ratio, calculated from the areas under the milk and plasma curves, respectively, was 23 compared with a ratio predicted to be about 0.3 on the basis of lipid partitioning and protein binding determinations. M/P ratios for two nitrofurantoin congeners were also calculated. The neutral compound furazolidone had a M/P ratio of about 1, as predicted, whereas the basic compound furaltadone had a M/P ratio of 3.49 compared with a predicted ratio of 1.4. These data suggest that nitrofurantoin and, to a lesser extent, furaltadone are actively transported across the mammary epithelium into milk.  相似文献   
16.
Intake of fish and omega-3 (n-3) fatty acids is associated with a reduced concentration of plasma triacylglycerols (TAG) but the mechanisms are not fully clarified. Stearoyl-CoA desaturase-1 (SCD1) activity, governing TAG synthesis, is affected by n-3 fatty acids. Peripheral blood mononuclear cells (PBMC) display expression of genes involved in lipid metabolism. The aim of the present study was to estimate whether intake of lean and fatty fish would influence n-3 fatty acids composition in plasma phospholipids (PL), serum TAG, 18:1n-9/18:0 ratio in plasma PL, as well as PBMC gene expression of SCD1 and fatty acid synthase (FAS). Healthy males and females (n = 30), aged 20–40, consumed either 150 g of cod, salmon, or potato (control) daily for 15 days. During intervention docosahexaenoic acid (DHA, 22:6n-3) increased in the cod group (P < 0.05), while TAG concentration decreased (P < 0.05). In the salmon group both eicosapentaenoic acid (EPA, 20:5n-3) and DHA increased (P < 0.05) whereas TAG concentration and the 18:1n-9/18:0 ratio decreased (P < 0.05). Reduction of the 18:1n-9/18:0 ratio was associated with a corresponding lowering of TAG (P < 0.05) and an increase in EPA and DHA (P < 0.05). The mRNA levels of SCD1 and FAS in PBMC were not significantly altered after intake of cod or salmon when compared with the control group. In conclusion, both lean and fatty fish may lower TAG, possibly by reducing the 18:1n-9/18:0 ratio related to allosteric inhibition of SCD1 activity, rather than by influencing the synthesis of enzyme protein.  相似文献   
17.
We have studied how different catalysts and diols affect the properties of low-molecular-weight (Mw (GPC) < 49800 g/mol) lactic-acid-based telechelic prepolymers. The catalysts and diols were tested separately in our previous studies. In this study, we used the best previously tested diols and catalysts together in order to prepare different types of telechelic prepolymers (for example, crystalline or amorphous). All condensation polymerizations were carried out in the melt, using different diols and different catalysts. The prepolymers were characterized by differential scanning calorimetry, gel permeation chromatography, titrimetric methods, and 13C nuclear magnetic resonance (13C-NMR). According to NMR, the resulting polymers contained less than 1 mol % of lactic acid monomer and less than 5.1 mol % of lactide. Dibutyltindilaurate, like tin(II)octoate, produced quite good molecular weights, but the resulting prepolymers contained exceptionally high amounts of D-lactic acid structures, and, therefore, these prepolymers were totally amorphous. Antimony(III)oxide produced a high-molecular-weight prepolymer when the diol used was aliphatic. Like DBTL, Sb2O3 produced amorphous prepolymers, which contained a lower amount of D-lactic acid structures than DBTL prepolymers. 1,8-dihydroxyanthraquinone produced a different kind of chain structure with Ti(IV)bu and Ti(IV)iso because one prepolymer had high crystallinity, and the other showed only a slight crystallinity. Sulphuric acid produced a very high-molecular-weight prepolymer with aliphatic 2-ethyl-1,3-hexanediol; and with aromatic diols, it produced quite good molecular weights, except with 1,8-dihydroxyanthraquinone. High-molecular-weight prepolymers produced with H2SO4 also showed high crystallinity; and, according to 13C-NMR, they did not contain lactide and D-lactic acid structures. © 1998 John Wiley & Sons, Inc. J Appl Polm Sci 67:1011–1016, 1998  相似文献   
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A silver/alumina catalyst was tested for its NO x reduction activity during oxygen-rich conditions and during variation in the input parameters (nitric oxide, octane and oxygen). The experimental data using the microreactor was investigated by means of artificial neural networks (ANN).  相似文献   
20.
Complete hydrogenation of d-galactose and l-arabinose mixtures on a Ru/C catalyst was achieved with excellent selectivities exceeding 95?%. No unexpected effects of temperature and pressure were observed. A detailed kinetic model was derived to describe the simultaneous hydrogenation of the monomeric sugars.  相似文献   
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