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121.
A 19-year-old man who had fulminant heart failure caused by an idiopathic dilated cardiomyopathy was supported with a left ventricular assist device for 183 days as a bridge to heart transplantation. At the time of intended transplantation it was noted that the patient's heart had returned to normal size, had a normal ejection fraction, and was able to maintain normal pressures and flows. In view of the apparent recovery of cardiac properties, the left ventricular assist device was explanted and the transplantation was not performed. However, the heart dilated, ejection fraction worsened, and the patient died of heart failure exacerbated acutely by a systemic viral illness. Although such recovery of systolic function is uncommon, as use of the left ventricular assist devices becomes more widespread other physicians might encounter similar findings and, in this regard, they might find our experience useful as they contemplate their treatment options. 相似文献
122.
J. A. MuñOz C. Go´mez A. Ballester M. L. Bla´zquez F. Gonza´lez M. Figueroa 《Journal of Applied Electrochemistry》1997,28(1):49-56
The electrochemical behaviour of massive chalcopyrite electrodes has been studied in an acid medium (pH1.5) containing silver ions (0.02gdm–3Ag+) and thermophilic bacteria (68°C). Preliminary tests on particulate electrodes made from graphite, elemental sulfur and Ag2S were included to determine the electrochemical response of reactants (Ag+) and products (S° and Ag2S) associated with the dissolution of chalcopyrite in the presence of silver. Massive chalcopyrite electrodes under potential scan showed a dependence on the dissolution of the Ag2S film with both the time of contact with the silver solution and [Ag+]. As well as Ag2S, metallic silver was detected on the chalcopyrite surface. It has been demonstrated that Fe3+ and bacteria play an important role in the regeneration of the Ag2S film. The breakdown of this film is a requirement for the further dissolution of chalcopyrite. The bioleaching of chalcopyrite with thermophilic microorganisms in the presence of silver decreased the decomposition potential of the electrode and favoured its electrodissolution. Bioleaching treatment in the presence of silver ions for periods of time longer than two weeks did not improve the surface reactivity. However, in the initial stages of the process, the lower reactivity of the bioleached electrodes was probably related to a toxic effect of silver on the microorganisms. 相似文献
123.
S Kaleli D K?sebay T Be?e F Demirkiran UA Oz M Arvas K Aydinli E Erkün 《Canadian Metallurgical Quarterly》1997,79(5):944-951
BACKGROUND: The purpose of this study was to determine the role of flow cytometric S-phase fraction as a prognostic factor in patients with endometrial adenocarcinoma. METHODS: The study included 80 patients with endometrial adenocarcinoma of endometrioid type who were followed regularly between 1984-1995 in the Department of Obstetrics and Gynecology at Cerrahpasa Faculty of Medicine in Istanbul, Turkey. The method employed for the flow cytometric analysis was modified from Hedley et al. RESULTS: The S-phase fraction was identified as the most significant variable associated with death from endometrial carcinoma of endometrioid type by the Cox proportional hazards model. The risk of death was significantly higher in patients with S-phase values greater than 20%. Aneuploidy and DNA indexes were also significant prognostic variables. CONCLUSIONS: The S-phase fraction is considered to be a significant prognostic variable in identifying those patients with endometrial carcinoma who have a poor prognosis. The authors believe that S-phase fraction distinguishes those patients who may benefit from additional treatment approaches. 相似文献
124.
125.
Heterocyclic aromatic amines (HAAs) are sometimes formed in meats and fish cooked at high temperatures. In the present study, the effects of cooking methods by deep-fat frying, pan-frying, grilling and barbecuing on the formation of HAAs of fillets of rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta fario) were investigated. Barbecued brown trout (1 g) was estimated to contain 0.12 ng of IQ (2-amino-3-methylimidazo[4,5-f]quinoline), 0.02 ng 4,8-DiMeIQx (2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline). Grilled rainbow trout (1 g) was estimated to contain 0.02 ng 4,8-DiMeIQx. MeIQ (2-amino-3,4-dimethylimidazo[4,5-f]quinoline), MeIQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) were not detectable in all cooked fish. 相似文献
126.
E. Altin E. Oz S. Demirel M. Erdem 《Journal of Materials Science: Materials in Electronics》2014,25(12):5331-5337
We fabricated La–Al–Sb alloy by arc melter system and the fabrication conditions were described in detail. Microstructural analyses were performed and it was found that LaSb, Al11La3 Al4La, AlLa3 and Sb phases formed for different heat treatment conditions. The resistivity results showed the metallic and semiconducting type behavior depending on heat treatment temperatures. The thermal-conductivity measurement was performed in the range of 2–300 K and the data were analyzed by the sum of lattice and carrier components. The linear temperature dependence of thermo power indicates metallic type characteristic of the samples. The micro-hardness values of the phases in the samples were analyzed and it was found that there are two different hardness regions in the samples. 相似文献
127.
Gabriella Szalai Nir Dai Avinoam Danin Nativ Dudai Oz Barazani 《Journal of the science of food and agriculture》2010,90(12):2039-2045
BACKGROUND: Portulaca oleracea (purslane) is nutritious but, in addition to the essential α‐linolenic acid, vitamin C and tocopherols, it contains undesirable oxalic acid. Knowing the effects of nitrate and ammonium on oxalate accumulation, we tested the agronomic potential of three members of the P. oleracea aggregate under various nitrogen fertilization conditions, by measuring biomass production and accumulation of fatty acids, organic acids and tocopherol in the commercial P. sativa (Pos) and two natural members: P. nitida (Pon) and P. papillato‐stellulata (Pop). RESULTS: With nitrate as the sole N source, we measured differences between Pon and Pos in concentrations of the essential ω‐3 fatty acid α‐linolenic acid. Pos also gained less dry biomass under these conditions, implying a higher agronomical and nutritional value for Pon. Increasing the fertilizer ammonium concentration and reducing that of nitrate significantly decreased oxalic acid by factors of up to 1.7, 2.6 and 3.4 in Pos, Pop and Pon, respectively, significantly increased concentrations of tocopherol and malic acid, had no effect on fatty acids or ascorbic acid, but reduced biomass. CONCLUSION: In spite of the recumbent growth habit of Pon, the present findings indicate its agronomic potential. Because early flowering and seed production may be the limiting factors in purslane agriculture, growing Pon in nitrate‐poor conditions might be agriculturally favorable. Copyright © 2010 Society of Chemical Industry 相似文献
128.
The effects of melt state compounding of ethylene‐butyl acrylate‐maleic anhydride (E‐BA‐MAH) terpolymer and/or three types of organoclays (Cloisite® 15A, 25A, and 30B) on thermal and mechanical properties and morphology of polyamide‐6 are investigated. E‐BA‐MAH formed spherical domains in the materials to which it is added, and increased the impact strength, whereas the organoclays decreased the impact strength. In general, the organoclays increased the tensile strength (except for Cloisite 15A), Young's modulus and elongation at break, but the addition of E‐BA‐MAH had the opposite effect. XRD patterns showed that the interlayer spacing for the organoclays Cloisite 25A and Cloisite 30B increased in both polyamide‐6/organoclay binary nanocomposites and in polyamide‐6/organoclay/impact modifier ternary systems. TEM analysis showed that exfoliated‐intercalated nanocomposites were formed. The crystallinities of polyamide‐6/organoclay nanocomposites were in general lower than that of polyamide‐6 (except for Cloisite 15A). In ternary nanocomposites, crystallinities generally were lower than those of polyamide‐6/organoclay nanocomposites. Cloisite 15A containing ternary nanocomposites had higher tensile and impact strengths and Young's modulus than the ternary nanocomposites prepared with Cloisite 25A and Cloisite 30B, owing to its surface hydrophobicity and compatibility with the impact modifier. POLYM. COMPOS., 2008. © 2007 Society of Plastics Engineers 相似文献
129.
In this study, the influences of microwave frying and various flour types on microstructure of batter coatings were investigated. Control batter formulation contained only wheat and corn flour. To determine the effects of different flour types, 30% of the corn and wheat flour mix was replaced with chickpea, rice or soy flours. Frying was performed in microwave oven at 365 W (70%) power level for 1.5 min after bringing the oil temperature to 180 ± 1 °C. Samples were also fried in a conventional fryer at 180 °C for 1.5 and 5.0 min for comparison. Microwave fried samples had higher specific bulk volume and porosity values and also smoother inner surface as compared to conventionally fried samples. Porosity values of different batter formulations were in the range of 0.425–0.484 in 1.5 min microwave fried chicken samples and 0.348–0.392 in 5.0 min conventionally fried ones. Microwave fried samples had comparable or lower hardness values than the conventionally fried ones depending on the flour type used in batter formulation. Microstructure of fried batter was different for different batter formulations. Microwave fried control and chickpea flour containing batter provided formation of larger gas cells on the outer surface. Soy flour containing batter resulted in smallest size gas cells for both frying methods. 相似文献
130.
Characterization of the genetic variability of Mediterranean Pistacia lentiscus genotypes by RAPD, composition of essential oils, and morphology is presented. High polymorphism in morphological parameters was found among accessions, with no significant differences in relation to geographical origin, or to gender. GC-MS analysis of leaves extracted by t-butyl methyl ether, showed 12 monoterpenes, seven sesquiterpenes, and one linear nonterpenic compound. Cluster analysis divided the accessions into two main groups according to the relative content of the major compounds, with no relation to their geographical origin. In contrast, a dendrogram based on RAPD analysis gave two main clusters according to their geographical origins. Low correlation was found between genetic and essential oil content matrices. High morphological and chemical variability on one hand, and genotypic polymorphism on the other, provide ecological advantages that might explain the distribution of Pistacia lentiscus over a wide range of habitats. The plants under study were grown together in the same climatic and environmental conditions, thus pointing to the plausible genetic basis of the observed phenotypic differences. 相似文献