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排序方式: 共有599条查询结果,搜索用时 15 毫秒
21.
22.
Hall Gordon C. Nagayama; Teten Andra L.; DeGarmo David S.; Sue Stanley; Stephens Kari A. 《Canadian Metallurgical Quarterly》2005,73(5):830
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
23.
Esraa Ali Andriy Trailin Filip Ambrozkiewicz Vclav Lika Kari Hemminki 《International journal of molecular sciences》2022,23(23)
Hepatocellular carcinoma (HCC) is a global healthcare challenge, which affects more than 815,000 new cases every year. Activated hepatic stellate cells (aHSCs) remain the principal cells that drive HCC onset and growth. aHSCs suppress the anti-tumor immune response through interaction with different immune cells. They also increase the deposition of the extracellular matrix proteins, challenging the reversion of fibrosis and increasing HCC growth and metastasis. Therapy for HCC was reported to activate HSCs, which could explain the low efficacy of current treatments. Conversely, recent studies aimed at the deactivation of HSCs show that they have been able to inhibit HCC growth. In this review article, we discuss the role of aHSCs in HCC pathophysiology and therapy. Finally, we provide suggestions for the experimental implementation of HSCs in HCC therapies. 相似文献
24.
Differential scanning calorimetric studies on structured lipids from coconut oil triglycerides containing stearic acid 总被引:1,自引:0,他引:1
Reena Rao Kadimi Udaya Sankar Kari Sambaiah B. R. Lokesh 《European Food Research and Technology》2001,212(3):334-343
Triglycerides from coconut oil contain high levels of lauric acid. They were replaced by incremental amounts of stearic acid by interesterification reactions catalyzed by immobilized lipase (IM 60 from Rhizomucor miehei). The reactions were carried out in organic solvents such as hexane. Maximum incorporation of stearic acid was observed by 4 h at 37vv°C or by 2 h at 60vv°C when triglycerides to fatty acid (stearic acid) ratio was maintained at 1v:Ң. The stearic acid level in coconut oil triglycerides was increased from an initial value of 2% to 60% under these conditions. The stearic acid replaced lauric, myristic, and palmitic acids in unmodified triglycerides. A major portion of stearic acid incorporated was found in positions 1 and 3 of triglycerides. Differential scanning calorimetry indicated that stearic acid enrichment increased the solid fat content and also the higher melting polymorphs in modified lipids. The studies also indicated that low melting polymorphic forms of coconut oil triglycerides are converted to higher melting forms by stearic acid enrichment. The modified lipids thus obtained can find use in various food applications. 相似文献
25.
Windhofer Karina Kari Alexander Prenninger Klaus Lange Stephan 《Forschung im Ingenieurwesen》2021,85(2):583-595
Forschung im Ingenieurwesen - Wind turbine noise used to be dominated by aerodynamic blade noise, effectively masking mechanical noise, originating from the drivetrain. Successful blade noise... 相似文献
26.
为提高风功率预测精度,减轻输出风能波动性对风电并网不利影响,提出了基于WT-IAGA-BP神经网络的短期风电功率预测方法。首先,利用风速分区、3σ准则及拉格朗日插值法清洗风电场历史数据;其次,依据小波重构误差,选择db4小波分别提取风速、风向、历史风功率的不同频率特征信号,并引入改进自适应遗传算法(IAGA)对各序列BP神经网络的初始权值与阈值寻优,使用Sigmiod函数通过适应度值自适应改变交叉概率与变异概率;最后,构建各序列的WT-IAGA-BP模型对短期风功率组合预测。通过仿真分析,并与ELM、WT-ELM及IAGA-BP方法对比,验证该方法具有更高的预测精度和更好的预测性能。 相似文献
27.
28.
Kari Rappa Jacob Samargia Mazhar Sher Javier S. Pino Harold F. Rodriguez Waseem Asghar 《Microfluidics and nanofluidics》2018,22(9):100
Quite puzzling issue in biology is how sperm cells are selected naturally where human sperm has to maintain a correct swimming behavior during the various stages of reproduction process. In nature, sperm has to compete a long journey from cervix to oocyte to stand a chance for fertilization. Although various guidance mechanisms such as chemical and thermal gradients are proposed previously, these mechanisms may only be relevant as sperm reaches very close to the oocyte. Rheotaxis, a phenomenon where sperm cells swim against the flow direction, is possibly the long-range sperm guidance mechanism for successful fertilization. A little is known quantitatively about how flow shear effects may help guide human sperm cells over long distances. Here, we have developed microfluidic devices to quantitatively investigate sperm rheotaxis at various physiological flow conditions. We observed that at certain flow rates sperm actively orient and swim against the flow. Sperm that exhibit positive rheotaxis show better motility and velocity than the control (no-flow condition), however, rheotaxis does not select sperm based on hyaluronic acid (HA) binding potential and morphology. Morphology and HA binding potential may not be a significant factor in sperm transport in natural sperm selection. 相似文献
29.
Telle-Hansen VH Larsen LN Høstmark AT Molin M Dahl L Almendingen K Ulven SM 《Lipids》2012,47(2):151-160
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
30.
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