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991.
Young-Woo Kim Bang Wool Eom Myeong-Cherl Kook Han-Seong Kim Mi-Kyung Kim Hai-Li Hwang Vishal Chandra Shiv Poojan Yura Song Jae-Soo Koh Chang-Dae Bae Jungsil Ro Kyeong-Man Hong 《Experimental & molecular medicine》2015,47(11):e193
Proliferation activity has already been established as a prognostic marker or as a marker for anticancer drug sensitivity. In gastric cancer, however, the prognostic significance of proliferation activity is still being debated. Several studies evaluating proliferation activity using Ki-67 have shown controversial results in terms of the relationship between proliferation activity and overall survival (OS) or drug sensitivity in gastric cancer patients. Because cytoskeleton-associated protein 2 (CKAP2) staining has recently been introduced as a marker of proliferation activity, we analyzed 437 gastric cancer tissues through CKAP2 immunohistochemistry, and we evaluated the chromatin CKAP2-positive cell count (CPCC) for proliferation activity. Although the CPCC did not show any significant correlation with OS in the male, female or total number of cases, it did show a significant correlation in the T1 or T2 male patient subgroup, according to log-rank tests (P=0.001) and univariate analysis (P=0.045). Additionally, multivariate analysis with the Cox proportional hazard regression model showed a significant correlation between the CPCC and OS (P=0.039) for the co-variables of age, gender, T stage, N stage, histology, tumor location, tumor size and adjuvant chemotherapy. In male gastric cancer cell lines, faster-growing cancer cells showed higher sensitivity to cisplatin than slow-growing cells. Thus our study indicates that CPCC-measured proliferation activity demonstrates a significantly worse prognosis in T1 or T2 male gastric cancer patients. The CPCC will help to more precisely classify gastric cancer patients and to select excellent candidates for adjuvant chemotherapy, which in turn will facilitate further clinical chemotherapeutic trials. 相似文献
992.
Jinju Ahn Hyejin Lee Tae‐Hyun Yang Chang‐Soo Kim Byungchan Bae 《Journal of polymer science. Part A, Polymer chemistry》2014,52(20):2947-2957
Multiblock sulfonated poly(arylene ether sulfone)s were synthesized to investigate the structural effects on their membrane properties. Three different types of sulfonated hydrophilic blocks were used; their structures possessed different acidity and local concentration of sulfonic acid groups. For the comparison between the block copolymers, a hydrophobic block with the same chemical structure and block length was used. The different acidities and local concentration were achieved using different sulfonation methods, such as postsulfonation and direct condensation with sulfonated monomers, and different monomers for preparing the hydrophilic block. The higher acidity and concentration of sulfonic acid groups resulted in higher proton conductivity under certain relative humidity conditions and phase separation as shown in the transmission electron microscopy analysis. The synthesized oligomers and polymers were well characterized, and the other physical properties were also investigated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2947–2957 相似文献
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This study seeks to elucidate the interplay of interfirm rivalry and aspiration formation. Organizational aspiration serves as a categorical judgment over a desirable level of organizational performance. While aspiration as a driver of collective decision-making inside the firm is well recognized, our understanding is still limited as to the competitive consequence of aspiration-induced actions. From a computational model of aspiration-induced R&D, where competition is biased towards the status quo, this study suggests that although radical innovation calls for flexibility and diversity inside the firm, aspiration-induced action favors consensus such as a firm with machine bureaucracy either (1) in a market where a majority of consumers are unable to discern a small quality improvement, i.e., demand difficult to satisfy or (2) in a market where competitive advantage dissipates quickly, i.e., an unstable environment. In particular, this study shows that: (1) the level of organizational aspiration has little to do with the sustainability of competitive advantage; (2) aspiration strength—i.e., the extent of consensus among decision makers of the firm as to a legitimate level of organizational aspiration—interacts with the change in competitive advantage. The leading firm is likely to lose its competitive advantage when a follower has a stronger aspiration than the leader in a market whose demand is difficult to satisfy; and (3) the effect of aspiration strength on the sustainability of competitive advantage increases whenever organizational assets depreciate over time. 相似文献
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In this work, novel thiol-ene (TE)/hyperbranched polymer(HBP) hybrid thin films have been prepared by a simple photopolymerization method and the TE/HBP system was also investigated in terms of thermocuring behavior and gas barrier properties. The effect of added HBP on thermal curing (cross-linking) of TE polymer was examined with dynamic and isothermal differential scanning calorimeter (DSC) and compared with photocuring reaction of identical system. The structure of prepared TE/HBP hybrid thin film was analyzed by X-ray diffraction (XRD). Themomechanical analysis (TMA) provided extensive data on the coefficient of linear thermal expansion (CTE), dimensional change upon heating, and isothermal profile of TE/HBP hybrid thin films. Light transmittance as well as water/oxygen permeability of the resulting TE/HBP hybrid thin film was also measured depending on the HBP content. 相似文献
1000.
The class of phase‐type distributions has recently gained much popularity in insurance applications due to its mathematical tractability and denseness in the class of distributions defined on positive real line. In this paper, we show how to use the phase‐type mortality law as an efficient risk management tool for various life insurance applications. In particular, pure premiums, benefit reserves, and risk‐loaded premiums using CTE for standard life insurance products are shown to be available in analytic forms, leading to efficient computation and straightforward implementation. A way to explicitly determine provisions for adverse deviation for interest rate and mortality is also proposed. Furthermore, we show how the interest rate risk embedded in life insurance portfolios can be analyzed via interest rate sensitivity index and diversification index which are constructed based on the decomposition of portfolio variance. We also consider the applicability of phase‐type mortality law under a few non‐flat term structures of interest rate. Lastly, we explore how other properties of phase‐type distributions may be applied to joint‐life products as well as subgroup risk ordering and pricing within a given pool of insureds. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献