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101.
Using regression splines to assess the impact of information technology investments on productivity in the health care industry 总被引:2,自引:0,他引:2
Abstract. This paper explores the impact of information technology (IT) investments on productivity using a new technique, multivariate adaptive regression splines (MARS). We believe that it provides additional insights on the nature of the impact of IT investments on productivity. The results from our study are compared with findings from a previous study that has also used the same data set. While the results of a previous study indicate that IT investments have a positive but uniform impact on productivity, our study suggests that the impact of IT on productivity is not uniform but is contingent on other complementary factors. Our findings describe that the complementary relationship exists between IT and non‐IT related investments. Thus, improved organizational productivity cannot be expected from investment in IT alone but only together with non‐IT investments. Our findings also point out that further investment may not necessarily bring on higher organizational productivity. 相似文献
102.
103.
包装产业是国民经济的支柱产业之一,富集先进生产力的诸多要素.新时期包装要注入"以人为本"理念,坚持科学发展观,与经济社会发展同进退、共荣辱,培育一代又一代杰出的包装人才,始终着力丰富先进生产力的内涵. 相似文献
104.
火炬树叶的抗氧化性及其与Vc协同作用的研究 总被引:3,自引:0,他引:3
赵爱云 《青岛大学学报(工程技术版)》2004,19(2):30-32
为研究火炬树叶的抗氧化性及其与Vc、柠檬酸的协同作用,本文以猪油为底物,采用高温诱导使其发生脂质过氧化反应,测定体系的过氧化值,结果表明:火炬树叶甲醇提取物可有效延缓猪油脂质过氧化反应,适量加入Vc可提高其抗氧化性。 相似文献
105.
The authors assessed the joint perceptions of the employee and his or her employer to examine mutuality and reciprocity in the employment relationship. Paired psychological contract reports were obtained from 80 employee-employer dyads in 16 university-based research centers. On the basis of in-depth study of the research setting, research directors were identified as primary agents for the university (employer) in shaping the terms of employment of staff scientists (employees). By assessing the extent of consistency between employee and employer beliefs regarding their exchange agreement, the present study mapped the variation and consequences of mutuality and reciprocity in psychological contracts. Results indicate that both mutuality and reciprocity are positively related to archival indicators of research productivity and career advancement, in addition to self-reported measures of Met Expectations and intention to continue working with the employer. Implications for psychological contract theory are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
In this study, the PEGylated nanostructured lipid carriers (PEG-NLC) were constructed for the intravenous delivery of 17-allylamino-17-demethoxygeldanamycin (17AAG). 17AAG-PEG-NLC was successfully prepared by the method of emulsion evaporation at a high temperature and solidification at a low temperature using a mixture of glycerol monostearate and PEG2000-stearate as solid lipids, and medium-chain triglyceride as the liquid lipid. The results revealed that the morphology of the NLC was spheroidal. The particle size, zeta potential and entrapment efficiency for 17AAG-PEG-NLC were observed as 189.4?nm, ?20.2 mV and 83.42%, respectively. X-ray diffraction analysis revealed that 17AAG existed as amorphous structures in the nanoparticles. In the in vitro release study, the 17AAG from 17AAG-PEG-NLC exhibited a biphasic release pattern with burst release initially and sustained release afterwards. In addition, 17AAG-PEG-NLC showed a significantly higher in vitro antitumor efficacy and longer retention time in vivo than 17AAG solution. These results indicated that 17AAG-PEG-NLC may offer a promising alternative to the current 17AAG formulations for the treatment of solid tumors. 相似文献
107.
大牛地气田大12-大66井区沉积微相与储层产能关系 总被引:1,自引:0,他引:1
以大牛地气田大12—大66井区为研究对象,基于物质供给和沉积水动力条件、河道结构与特征,探讨了沉积微相纵向结构与产能分布之间的成因关系,沉积微相横向结构与产能分布之间的内在关系。研究表明,物质供给和沉积水动力条件的组合关系是影响沉积微相纵向产能分布规律,其中物质供给充分、稳定的强水动力条件下,主要为中高产气层;分流河道微相中心位置,测试产能相对稳定,中高产气层分布比较多。分流河道微相边部,测试产能有不稳定的特点。两个强水动力沉积的河道交汇处,是中、高产气层的密集发育区。另外,曲流化的固定河道,因复杂化而形状变化大、难钻遇,但潜力大。不稳定河道,储层整体产能低,但强水动力沉积区仍具挖潜价值。研究结果与大12—大66井区生产测试结果吻合。 相似文献
108.
Lipolysis and lipid oxidation caused by Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 isolated from Suan yu,a traditional Chinese low‐salt fermented fish
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Pei Gao Weixin Wang Wenshui Xia Yanshun Xu Qixing Jiang 《International Journal of Food Science & Technology》2016,51(2):419-426
The aim of this study was to investigate the lipolysis and lipid oxidation of Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 in Suan yu. Suan yu were made inoculated with and without two strains at different stages, and model systems of emulsions were also established. Lipolysis and lipid oxidation were evaluated by determining the changes in free fatty acid (FFA) content and composition, conjugated diene (CD) value and thiobarbituric acid reactive substances (TBARS) value. The total FFA of the sample without cultures increased from 476.61 mg/100 g fat to 1413.89 mg/100 g fat after 5 weeks fermentation, while those of samples with cultures declined to 258.98 and 452.89 mg/100 g fat, respectively. On the other hand, CD and TBARS values of samples with inoculation markedly increased. In the model system, higher FFA, CD and TBARS values for the samples added with CFE were observed. This study showed that Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31 made a significant contribution to lipolysis and lipid oxidation during the processing of Suan yu. 相似文献
109.
The objective of the present investigation was to improve the skin deposition and retention of metronidazole (MTZ) in rosacea therapy by incorporating it into nanostructured lipid carriers (NLCs). The main challenge in this endeavor was the partial hydrophilicity of MTZ, which mandated careful selection of excipients, including solid and liquid lipids, surfactants, and their ratios in combination. NLCs were produced by the phase inversion temperature method and finally converted into a gel for topical application. The prepared nanoparticles were evaluated for their particle size, zeta potential, entrapment efficiency, solid-state characteristics, surface morphology, in vitro drug release, and permeation through excised skin. The gel was additionally characterized for its pH, drug content, viscosity, and spreadability. The prepared nanoparticles were spherical in shape and of size less than 300?nm. Incorporation of judiciously chosen excipients made possible a relatively high entrapment efficiency of almost 40%. The drug release was found to be biphasic, with an initial burst release followed by sustained release up to 8?hours. In comparison to the plain drug gel, which had a tissue deposition of 11.23%, the NLC gel showed a much superior and desirable deposition of 26.41%. The lipophilic nature of the carrier, its size, and property of occlusion enabled greater amounts of drug to enter and be retained in the skin, simultaneously minimizing permeation through the skin, i.e. systemic exposure. The results of the study suggest that NLCs of anti-rosacea drugs have the potential to be used in the therapy of rosacea. 相似文献
110.
《Drug development and industrial pharmacy》2013,39(4):439-448
Background: As a promising anticancer drug, severe side-effects of current clinical formulations for paclitaxel have restricted its use, developing a better technical-economical formulation for paclitaxel delivery is needed. Method: In this study, the compound of folate-poly(ethylene glycol) (PEG)-phosphatidylethanolamine was synthesized and characterized with Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The solid-liquid lipid nanoparticle (SLLN) for paclitaxel modified with folate and poly(ethylene glycol) (folate-PEG-SLLN) was prepared and characterized. Morphology of folate-PEG-SLLN was examined by transmission electron microscopy. The particle size and zeta potential were performed by Zetapals. Encapsulation efficiency was analyzed by HPLC. The in vitro drug release of paclitaxel was investigated via membrane dialysis. The in vivo pharmacokinetics was measured with male Sprague-Dawley rats. Treatment efficiency was investigated with the mouse with sarcoma180 ascites tumor. Results: Paclitaxel loaded on the newly designed binary SLLN showed a longer and sustained in vitro releasing property. More importantly, S180 tumor-bearing mice treated with paclitaxel-loaded SLLN exhibited higher tumor inhibition rate, comparing with animals administered with paclitaxel injection alone (45.3% and 37.3%, respectively). Conclusion: The newly developed paclitaxel delivery system may have improved in vivo antitumor activity. The results demonstrated a great interest to use folate-mediated SLLN as a prospective drug delivery system for paclitaxel. 相似文献