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131.
1. Arterial blood from 63 male (315-500 g) and 60 female (210-290 g) healthy Sprague-Dawley rats was analyzed for 16 hematological and 22 clinical chemistry parameters. 2. Nine of these parameters were associated with growth and developmental changes in males between 38-78 days and females 49 - 89 days of age. 3. Weight gain in both sexes followed patterns consistent with other studies using this strain, but interexperimental variation was as much as +/-22%. 4. Rectal temperatures of females averaged 37.28 degrees C, being statistically greater (P < 0.05) than the average male at 36.99 degrees C. 5. The data provide reference values for use in toxicological and other investigations.  相似文献   
132.
Addresses motivations for and reactions to augmentation mammoplasty and reports on a study of 32 adult Caucasian women who were followed for a minimum of 1 yr after surgery. The positive impact of offering the possibility for postoperative volume adjustment is noted. Contraindications for this surgery and possibilities for interdisciplinary collaboration are stressed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
133.
This work deals with the existence and uniqueness of the acceleration and contact forces for Lagrangian systems subject to bilateral and/or unilateral constraints with or without sliding Coulomb’s friction. Sliding friction is known to yield singularities in the system, such as Painlevé’s paradox. Our work aims at providing sufficient conditions on the parameters of the system so that singularities are avoided (i.e., the contact problem is at least solvable). To this end, the frictional problem is treated as a perturbation of the frictionless case. We provide explicit criteria, in the form of calculable upper bounds on the friction coefficients, under which the frictional contact problem is guaranteed to remain well-posed. Complementarity problems, variational inequalities, quadratic programs and inclusions in normal cones are central tools.  相似文献   
134.
Since its widespread use in concrete began over 100 years ago, the chemical composition and physical properties of portland cement have changed only incrementally in response to various and competing pressures of constructability and cost. Instead, the construction demands have been met largely through the development and introduction of chemical admixtures that are added to the binder during mixing. These same demands persist into the 21st Century and are just as important now as before, yet newer driving forces are simultaneously pushing the industry both toward more automated construction and toward more sustainable concrete materials that generate lower CO2 and have longer service life. These new cement binder formulations and new construction technologies are expected to go well outside the bounds of traditional portland cement compositions and batching and placing practices. This study examines the origins of these new market demands and the influence they are having on the construction industry. Seven scientific or technological pathways are identified that will be critical for enabling the kinds of transformational changes in cement and concrete construction that the industry needs: (i) additive manufacturing, (ii) designer admixtures, (iii) curated materials data repositories, (iv) computationally designed composites, (v) big data and smart materials, (vi) alternative binder compositions, and (vii) next‐generation instrumentation.  相似文献   
135.
Lipid emulsions for parenteral nutrition are used to provide calories and essential fatty acids for patients. They have been associated with hypertriglyceridemia, hypercholesterolemia, and metabolic stress, which may promote the development of endothelial dysfunction in patients. The aim of the present study was to determine whether five different industrial lipid emulsions may affect the endothelial function of coronary arteries. Porcine coronary artery rings were incubated with lipid emulsions 0.5, 1, or 2% (v/v) for 30 min before the determination of vascular reactivity in organ chambers and the level of oxidative stress using electron paramagnetic resonance. Incubation of coronary artery rings with either Lipidem®, Medialipid® containing long- and medium-chain triacylglycerols (LCT/MCT), or SMOFlipid® containing LCT, MCT, omega-9, and -3, significantly reduced the bradykinin-induced endothelium-dependent relaxation, affecting both the nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH) components, whereas, Intralipid® containing LCT (soybean oil) and ClinOleic® containing LCT (soybean and olive oil) did not have such an effect. The endothelial dysfunction induced by Lipidem® was significantly improved by indomethacin, a cyclooxygenase (COX) inhibitor, inhibitors of oxidative stress (N-acetylcysteine, superoxide dismutase, catalase) and transition metal chelating agents (neocuproine, tetrathiomolybdate, deferoxamine and l-histidine). Lipidem® significantly increased the arterial level of oxidative stress. The present findings indicate that lipid emulsions containing LCT/MCT induce endothelial dysfunction in coronary artery rings by blunting both NO- and EDH-mediated relaxations. The Lipidem®-induced endothelial dysfunction is associated with increased vascular oxidative stress and the formation of COX-derived vasoconstrictor prostanoids.  相似文献   
136.
137.
Zinc-containing hydroxyapatite particles (Zn/HAp) were prepared by an ion exchange reaction process involving hydroxyapatite (HAp) particles with aqueous solutions containing various amounts of zinc nitrate. The Zn2+ ion was partially substituted for the Ca2+ ion position in the HAp lattice, and hence, the obtained samples had changed little in crystallinity, particle size, and specific surface area. Adsorption of bovine serum albumin (BSA) and β2-microglobulin (β2-MG) in solutions containing both BSA and β2-MG was examined. As the Zn2+ ion content in the apatites increased, the adsorbed amount of BSA was almost constant, whereas that of β2-MG increased.  相似文献   
138.
Leaves of two highly aromatic plants,Artemisia tridentata (Nutt.) andMonarda fistulosa L., prepared according to a patented process, inhibited oviposition by the Mexican bean weevil,Zabrotes subfasciatus (Boheman), in beans at concentrations less than 1% w/w. Both plant species were less effective against the rice weevil,Sitophilus oryzae L., in wheat, with onlyM. fistulosa exhibiting any concentration-dependent activity. The maximal control achieved against this species was less than 50% at 3% w/w. Two less aromatic plant species,Balsamorhiza sagittata (Pursh.) Nutt. andGeranium viscosissimum Fisch. and Mey., caused only low levels of inhibition against both insect species. Volatiles probably caused the response toA. tridentata andM. fistulosa, while the asymptotic concentration dependence for the less volatile plant material was likely caused by behavioral factors related to the physical presence of foreign particulate matter in the foodstuff. Chemical analysis indicated that most of the volatile components from the dried leaf material from all species were terpenoids, with camphor (9.7 mg/g) and 1,8-cineole (4.0 mg/g) being most abundant inA. tridentata and carvacrol (26.3 mg/g) being most abundant inM. fistulosa.Portions of this research were conducted by the U.S. Department of Agriculture. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap. This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by USDA.  相似文献   
139.
核电站循环冷却水系统的消毒是核电水系统的研究重点.以法国丹皮尔核电站冷却塔模型为研究对象,进行一氯胺消毒剂的消耗动力学研究,确定以天然原水为循环水介质的一氯胺消耗动力学符合一级反应的动力学模型,其反应速率常数为0.002min^-1;以人工模拟投加Fe^3+进行一氯胺消耗分析表明,Fe^3+对一氯胺的消耗无显著影响.  相似文献   
140.
A number of techniques have previously been developed that use low field nuclear magnetic resonance (NMR) relaxometry for conventional and heavy oil reservoir characterization. In the current work, the adaptation of these algorithms for use in the oil sands industry is presented. NMR based methods have been developed for identification of water and bitumen content in ore and froth samples. Consistent algorithms have been used to analyze over 500 ore samples and 50 froth samples from the Athabasca oil sands in northern Alberta. Preliminary analyses are shown, with applications for in‐situ fluid determination using NMR logging tools and improved process control in oil sands processing plants.  相似文献   
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