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991.
Wai Kiong Chong Sanat Kumar Carl T. Haas Salwa M. A. Beheiry Lonnie Coplen Marvin Oey 《Canadian Metallurgical Quarterly》2009,25(3):143-154
The highly influential Brundtland report released in 1987 was the first document to define the three pillars of modern sustainable development as environmental, social, and economic. The Rio Summit in 1992, the Kyoto Protocol in 1997, and the Johannesburg Meeting in 2002 followed up with primary focus on the needs of society and the environment. Economic issues were secondary at these meetings. This movement was the beginning of what has been passed down to the construction industry as sustainable construction. Within the industry, however, confusion reigns, and attitudes toward sustainable construction vary wildly. Understanding perceptions of sustainability in the industry would help to navigate a path towards a common understanding of the issues, to reach a point from which a reasoned dialogue could ensue concerning the relative merits of different approaches to sustainability and to sustainable construction itself. To understand perceptions of sustainability in the construction industry, a survey of close to 200 practitioners was conducted between July and Sept. 2006. Its results are described and analyzed in this article. Some conclusions are made and recommendations are suggested based on this analysis. In particular, it is clear that a persistent and broad-based effort will be required to introduce sustainability effectively to the profession. 相似文献
992.
993.
Reviews the book, A new psychology of men edited by Ronald F. Levant and William S. Pollack (see record 1995-97524-000). The intent of this book is to "'describe how men's prescribed roles are neither biological nor social givens but rather psychological and social constructions.'" The Theory section includes four chapters primarily focused on social constructivism and psychoanalytic (or perhaps more accurately object-relations theory) views on masculinity. The second section, Research, provides three chapters by researchers of what seem to be disparate orientations. The third section, Applications, is appropriately more practical and speaks to clinicians. The fourth and final section, The Varieties of Masculinity, samples in three chapters issues of ethnic minority males, homosexual and bisexual males, and a final chapter (by the editors) looking to the future and summarizing conclusions from the preceding chapters. The reviewer finds several flaws in this book including interventions that are not applicable and an imbalance in the authors' orientations. However, the reviewer believes that researchers may find the volume helpful in generating hypotheses and new research directions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
995.
ES Haas DW Armbruster BM Vucson CJ Daniels JW Brown 《Canadian Metallurgical Quarterly》1996,24(7):1252-1259
The relationship between central serotonergic activities and voluntary alcohol consumption was studied in Sprague-Dawley rats, which normally have low alcohol preference. After initial screening for an evenly matched baseline alcohol preference, selective central serotonergic lesioning was induced by intracisternal injection of the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT). Control rats received injections of vehicle only. Both 5,7-DHT and vehicle-treated rats were further divided into two subgroups, which either had continued free access to ethanol (alcohol-drinking) or were deprived of it (alcohol-free). All rats were then tested again for alcohol preference. All rats were then killed, and the levels of monoamines in the brains were determined by high performance liquid chromatography with electrochemical detection. Behavioral results indicated that all 5,7-DHT-treated rats had significantly higher alcohol preference and consumption than the corresponding sham controls. Except in the cerebellum, the 5,7-DHT-treated rats had significantly lower levels of serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in most brain regions compared with those in the corresponding sham controls. Treatment with 5,7-DHT also resulted in a decrease in serotonin turnover in all brain regions in the alcohol-free rats, except in the cerebellum. In alcohol-drinking rats, however, 5,7-DHT treatment only reduced serotonin turnover in the pons. The levels of norepinephrine and dopamine in several brain regions were not significantly different. Thus, it appeared that in the Sprague Dawley rats, 5,7-DHT treatment depleted 5-HT and 5-HIAA levels in most brain regions while increasing alcohol consumption. Chronic alcohol-drinking attenuated the increase in alcohol consumption associated with serotonergic lesions. Voluntary alcohol consumption seemed more associated with 5-HT turnover than with tissue 5-HT levels. Our data also suggested that tolerance to alcohol-induced hypothermia was primarily attributable to long-term alcohol drinking rather than serotonergic lesioning. 相似文献
996.
In order to study the effect of high-dose therapy with peripheral blood stem cell transplantation (PBSCT) on the haemopoietic reserve in man, the number and composition of bone marrow (BM) and peripheral blood (PB)-derived progenitor cells were examined in 137 cancer patients. In 45 patients, paired samples from BM and PB were obtained before PBSC mobilization and 6-27 months after transplantation. Following PBSCT. the proportion of CD34+ cells was significantly smaller than before mobilization (BM 1.99 +/- 0.24 versus 0.8 +/- 0.09, P < 0.001), and no change was observed at several follow-up visits thereafter. The reduction was most pronounced for the primitive BM progenitor subsets such as the CD34+/DR- and CD34+/ Thy-1+ cells. The impairment of hematopoiesis was also reflected by a significant reduction in the plating efficiency of BM and PB samples. No relationship was found between the decrease in the proportion of CD34+ cells and any particular patient characteristics, kind of high-dose therapy or the CD34+ cell content in the autograft. In conclusion, high-dose therapy with PBSC transplantation is associated with a long-term impairment of the haemopoietic system. The reduction in the number of haemopoietic progenitor cells is not associated with a functional deficit, as peripheral blood counts post-transplantation were normal in the majority of patients. 相似文献
997.
998.
The abilities of three commercially available lipases—Lipozyme IM 20, Amano PS-30, and Amano CE—to synthesize fatty acid ethyl
esters via the alcoholysis of soy triglycerides (TG) and phosphatidylcholine (PC) in grade No. 2 diesel fuel were investigated.
All three enzyme preparations were active in water-saturated diesel fuel, synthesizing fatty acid esters from both TG and
PC. Response surface methodology, based on a Modified Central Composite design, was employed to examine the coordinate effects
of lipid, water, and ethanol concentrations on enzyme activities and to identify conditions yielding maximum alcoholysis.
For all three enzymes, optimal activities toward TG occurred at added water concentrations of less than 0.3 M. With PC as
substrate, optimal enzyme activities occurred at added water concentrations as much as tenfold greater than this, and the
amount of water required for maximum activity was proportional to the substrate concentration. For both substrates the enzyme
activities were generally reduced as ethanol concentrations rose. The exceptions to this were the Lipozyme-TG combination,
where activity increased with increasing ethanol concentrations, and the PS-30-PC combination, where activity was roughly
constant across the range of water and ethanol concentrations examined. Hydrolytic activities of the enzymes in aqueous reactions
were poor predictors of transesterification activity in organic solvent: the aqueous hydrolytic activities of CE and PS-30
toward TG were roughly comparable, and 25 to 50 times greater than that of IM 20. However, in the alcoholysis of TG in diesel
fuel the order of activities was PS-30>IM 20>CE. The activities of Lipozyme and CE toward PC were similar to one another,
and PS-30 was considerably less active on this substrate. CE lipase was more active toward PC than toward TG. Lipozyme displayed
comparable activity toward the two substrates. PS-30 was considerably more active on TG than on PC. Degrees of conversion
were consistent with the transesterification of only one fatty acid of TG, and slightly greater than one fatty acid for PC.
Preliminary studies indicated that for CE and PS-30, but not for Lipozyme IM 20, the degree of conversion of TG, but not PC,
could be significantly increased by the further provision of ethanol. Expansion of this work could lead to a method for the
production of simple fatty acid esters, which are suitable as diesel fuels, from multicomponent agricultural materials containing
TG and PC. 相似文献
999.
BACKGROUND: 5-aminosalicylic acid (5-ASA) is widely used as topical treatment in patients with distal inflammatory bowel disease. The enema spread and retention time are considered to be important factors in the efficacy of this therapeutic agent. Whereas colonic spread is widely investigated in selected patient populations and volunteers, much less attention has been given to the in vitro differences of physical and chemical properties, although they may influence the in vivo characteristics. METHODS: Two different brand enemas, Salofalk and Asacol, both containing 2 g mesalazine, were compared with respect to their in vivo and in vitro characteristics. The retrograde spread, maximum distribution and wall adhesion, as well as the retention time of the enemas, was examined by the addition of a technetium tracer dose in 12 healthy volunteers on two separate occasions. In addition, several chemical properties such as pH, viscosity, particle size, dispersion rate, specific surface area and residual volume after application were analysed and compared. RESULTS: With its larger volume and higher viscosity the Asacol preparation reached a substantially larger proportion of the colon and produced a significantly higher retention time in the proximal parts of the large intestine. In addition, more than double the amount of 5-aminosalicylic acid was not expelled from the semi-rigid Salofalk enema container after application. With respect to chemical properties it was demonstrated that the Asacol preparation showed a significantly smaller size of micronized 5-aminosalicylic acid particles, better homogeneity and much less aggregation of the drug. This resulted in an almost threefold higher specific surface area per g active compound. CONCLUSIONS: The Asacol enema appears to be superior in several aspects of the galenical formulation. The better dispersion and larger specific surface area, in conjunction with a larger distribution, better bowel wall adherence and retention time in vivo, constitute a clear theoretical and possible clinical advantage. 相似文献
1000.
OBJECTIVE: Inflammatory bowel disease (IBD) is characterized by T cell activation. Activated T cells shed interleukin-2 receptors (IL-2R) in a soluble form. A positive correlation between sIL-2Ralpha (CD25) and disease activity is well documented in IBD, whereas IL-2Rgamma (CD132) has not been investigated in this respect. Sera from 42 patients with ulcerative colitis (UC), 34 with Crohn's disease (CD), 31 healthy volunteers, and 12 patients with infectious enterocolitis were obtained. METHODS: Disease activity was scored according to a semiquantitative score for UC and CD. sIL-2R alpha chain and gamma chain were assessed by sandwich ELISA techniques using monoclonal antibodies specific for CD25 and CD132, respectively. RESULTS: The concentration of IL-2Ralpha chain (CD25) was found to be median 3.8 ng/ml in healthy volunteers versus 7.0 ng/ml in UC patients (p < 0.001), and 9.6 ng/ml in CD patients (p < 0.001). With respect to IL-2Rgamma (CD132), significantly higher amounts were found in CD patients: 6.6 ng/ml as compared with healthy controls <1.0 ng/ml (p < 0.004). A Kruskal-Wallis test revealed a significant correlation between alpha chain and disease activity in CD (p < 0.001), and further significantly higher gamma chain levels were found in active CD (p = 0.03). For UC patients, a statistically significant increase of the alpha chain with increasing disease activity (p < 0.01) was observed, whereas no significant changes of the gamma chain levels were found (p > 0.05). A difference of gamma chain levels were found between CD and UC in moderate and severe disease activity (p < 0.05). Further analyses revealed that mesalazine did not influence the IL-2Ralpha or -gamma concentration either in UC or in CD patients. CONCLUSION: An increased circulating level of the soluble common gamma chain (CD132) seems to be found in CD, and an overlap exists between CD and UC. 相似文献