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81.
Thin films containing 0 to 100 vol%Cu was prepared by thermal co-evaporation. The samples were 200 nm thick, deposited at 600 K at a rate of 0.8 nm/s. DC conductivity measurements were carried out using the van der Pauw four probe technique for 0 to 100 vol%Cu films in the temperature range 150 to 600 K. Samples containing 60 vol%Cu exhibited a metallic-like behaviour with positive TCR whereas lower concentrations exhibited an activated conduction mechanism with negative TCR.  相似文献   
82.
83.
Adult attachment orientation has been associated with specific patterns of emotion regulation. The present research examined the effects of attachment orientation on the perceptual processing of emotional stimuli. Experimental participants played computerized movies of faces that expressed happiness, sadness, and anger. Over the course of the movies, the facial expressions became neutral. Participants reported the frame at which the initial expression no longer appeared on the face. Under conditions of no distress (Study 1), fearfully attached individuals saw the offset of both happiness and anger earlier, and preoccupied and dismissive individuals later, than the securely attached individuals. Under conditions of distress (Study 2), insecurely attached individuals perceived the offset of negative facial expressions as occurring later than did the secure individuals, and fearfully attached individuals saw the offset later than either of the other insecure groups. The mechanisms underlying the effects are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Thirty samples of Pu-Erh tea (a microbial fermented Chinese tea) were collected and assayed for cholesterol synthesis inhibitory activity and polyphenol composition. All samples were able to inhibit the cholesterol biosynthesis in Hep G2 cell model and the inhibition ratios ranged from 7% to 35%. The inhibition abilities of tea polyphenol standards were in the order of gallocatechin gallate (GCG) > epigallocatechin gallate (EGCG) > epicatechin gallate (ECG) > gallic acid > epigallocatechin (EGC) > myricetin > quercetin > catechin (C) > epicatechin (EC). It appears that catechins with a galloyl structure on the B ring or a gallic acid moiety in the structure would have better inhibitory activity. In summary, tea polyphenol may play a role on the cholesterol biosynthesis inhibitory ability of Pu-Erh tea.  相似文献   
85.
People using computer systems naturally relate what they are experiencing to what they already know. This general cognitive process can be classified into metaphoric, analogical, and modelling processes. Metaphor, a term applied often to today's computer systems, is the process of representing the computer system with objects and events from a noncomputer domain, such as the popular desktop metaphor. Analogy is a comparison between objects or events that serve the same purpose but have different representations. Models are representations of the abstract conceptual structure of a computer system. This paper outlines the differences between these three processes and applies them to the computer domain. Implications for computer systems design are also discussed.  相似文献   
86.
The relation of physician and patient gender to verbal and nonverbal communication was examined in 100 routine medical visits. Female physicians conducted longer visits, made more positive statements, made more partnership statements, asked more questions, made more back-channel responses, and smiled and nodded more. Patients made more partnership statements and gave more medical information to female physicians. The combinations of female physician–female patient and female physician–male patient received special attention in planned contrasts. These combinations showed distinctive patterns of physician and patient behavior, especially in nonverbal communication. The relation of the results to gender differences in nonclinical settings, role strains in medical visits, and current trends in medical education are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
87.
Sintering resistance of a novel thermal barrier coating NdxZr1  xOy with Z dissolved in, where 0 < x < 0.5, 1.75 < y < 2 and Z is an oxide of a metal selected from Y, Mg, Ca, Hf and mixtures thereof, was studied. The coatings of NdxZr1  xOy and typical 7YSZ were deposited by electron beam physical vapor deposition (EB-PVD) and air plasma spray (APS). The samples with the coating system of EB-PVD NdxZr1 − xOy or 7YSZ overlaid onto a MCrAlY bond coat were cyclically sintered at 1107 °C for 706 hours. The freestanding coatings of EB-PVD NdxZr1  xOy and 7YSZ were isothermally sintered at 1371 °C for 500 hours. The microstructure of EB-PVD NdxZr1 − xOy before and after the sintering was evaluated and compared with EB-PVD 7YSZ. The sintering resistance of freestanding APS NdxZr1 − xOy coating was also investigated after isothermal sintering at 1200 °C for 50 and 100 hours. The results demonstrated that the new coatings of NdxZr1 − xOy applied with both EB-PVD and APS have higher sintering resistance than EB-PVD and APS 7YSZ, respectively.  相似文献   
88.
The blood–brain barrier (BBB) is a highly selective and restrictive semipermeable network of cells and blood vessel constituents. All components of the neurovascular unit give to the BBB its crucial and protective function, i.e., to regulate homeostasis in the central nervous system (CNS) by removing substances from the endothelial compartment and supplying the brain with nutrients and other endogenous compounds. Many transporters have been identified that play a role in maintaining BBB integrity and homeostasis. As such, the restrictive nature of the BBB provides an obstacle for drug delivery to the CNS. Nevertheless, according to their physicochemical or pharmacological properties, drugs may reach the CNS by passive diffusion or be subjected to putative influx and/or efflux through BBB membrane transporters, allowing or limiting their distribution to the CNS. Drug transporters functionally expressed on various compartments of the BBB involve numerous proteins from either the ATP-binding cassette (ABC) or the solute carrier (SLC) superfamilies. Pathophysiological stressors, age, and age-associated disorders may alter the expression level and functionality of transporter protein elements that modulate drug distribution and accumulation into the brain, namely, drug efficacy and toxicity. This review focuses and sheds light on the influence of inflammatory conditions and diseases such as Alzheimer’s disease, epilepsy, and stroke on the expression and functionality of the BBB drug transporters, the consequential modulation of drug distribution to the brain, and their impact on drug efficacy and toxicity.  相似文献   
89.
Cytochrome P450 reductase (CYPOR) provides electrons to all human microsomal cytochrome P450s (cyt P450s). The length and sequence of the “140s” FMN binding loop of CYPOR has been shown to be a key determinant of its redox potential and activity with cyt P450s. Shortening the “140s loop” by deleting glycine-141(ΔGly141) and by engineering a second mutant that mimics flavo-cytochrome P450 BM3 (ΔGly141/Glu142Asn) resulted in mutants that formed an unstable anionic semiquinone. In an attempt to understand the molecular basis of the inability of these mutants to support activity with cyt P450, we expressed, purified, and determined their ability to reduce ferric P450. Our results showed that the ΔGly141 mutant with a very mobile loop only reduced ~7% of cyt P450 with a rate similar to that of the wild type. On the other hand, the more stable loop in the ΔGly141/Glu142Asn mutant allowed for ~55% of the cyt P450 to be reduced ~60% faster than the wild type. Our results reveal that the poor activity of the ΔGly141 mutant is primarily accounted for by its markedly diminished ability to reduce ferric cyt P450. In contrast, the poor activity of the ΔGly141/Glu142Asn mutant is presumably a consequence of the altered structure and mobility of the “140s loop”.  相似文献   
90.
Platinum resistance is a major cause of treatment failure in ovarian cancer. We previously identified matrix metalloproteinase 9 (MMP-9) as a potential therapeutic target of chemoresistant disease. A2780cis (cisplatin-resistant) and A2780 (cisplatin-sensitive) ovarian carcinoma cell lines were used. The cytotoxic effect of MMP-9/MMP-2 inhibitor, (2R)-2-[(4-Biphenylsulfonyl) amino]-3 phenylpropionic acid (C21H19NO4S) alone or in combination with cisplatin was determined using high content screening. Protein expression was examined using immunohistochemistry and ELISA. Co-incubation of cisplatin and an MMP-9/MMP-2 inhibitor, (2R)-2-[(4-Biphenylsulfonyl) amino]-3 phenylpropionic acid (C21H19NO4S) resulted in significantly greater cytotoxicity as compared to either treatment alone in a cisplatin resistant MMP-9 overexpressing cell line; A2780cis. In addition, pre-incubating with MMP-9i prior to cisplatin further enhances the cytotoxic effect. No significant difference was observed in MMP-9 protein in tissue but a trend towards increased MMP-9 was observed in recurrent serum. We propose that MMP-9/MMP-2i may be utilized in the treatment of recurrent/chemoresistant ovarian cancers that overexpress MMP-9 mRNA but its role in vivo remains to be evaluated.  相似文献   
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