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51.
The role of the cellular redox state in the control of gluconeogenesis was studied in hemoglobin-free perfused chicken liver, by fluorimetric measurement of the redox states of intracellular pyridine nucleotides. The aminotransferase inhibitor, aminooxyacetate, completely inhibited gluconeogenesis from lactate in the perfused rat liver and to a small extent in the perfused chicken liver. In chicken liver, the highest rate of glucose production was seen with lactate, followed by fructose, pyruvate, and glycerol. When compared at 5 mM, the rate of glucose production from pyruvate was only 10% of that from lactate. Glucose production from a pyruvate/lactate mixture decreased with increasing proportions of pyruvate, together with redox changes of pyridine nucleotides to a more oxidized state. Increased reduction of pyridine nucleotides upon infusion of ethanol was associated with an increased glucose production from pyruvate, and the increase was abolished during octanoate infusion. This abolishment was accompanied by an increase in the acetoacetate to beta-hydroxybutyrate ratio with an oxidation of pyridine nucleotides. The octanoate-inhibited gluconeogenesis occurred at the higher lactate concentration (10 mM) with a transient oxidation of pyridine nucleotides. No significant inhibition was observed at 1 mM lactate, although an instant reduction of pyridine nucleotides was taking place. The rate of beta-hydroxybutyrate generation during octanoate infusion was 2.2 times higher at 1 mM than at 10 mM lactate. The inhibitory effect of octanoate on glyconeogenesis was completely relieved by the addition of NH4Cl. The results demonstrate that the regeneration of NADH in the cytosol is limited in chicken liver, and that gluconeogenesis is regulated, in part, by alteration in the redox states of mitochondria and cytosol.  相似文献   
52.
53.
The polymerization of β-propiolactone (βPL) by sodium acetate catalyst has been investigated. The polymerization behavior with monomer purified with calcium chloride was found to be a little different from that previously reported for this monomer. That is, poly-β-propiolactone (PβPL) obtained from βPL dried with CaCl2 has a higher degree of polymerization than that obtained from conventionally treated βPL, and its infrared spectrum shows type II configuration, which differs from that reported in previous papers. Some chain transfer reaction is observed even for the polymerization of the CaCl2–dried βPL; however, this is less important in toluene. The electronegativity of the anion or cation in catalyst greatly influences the rate of polymerization.  相似文献   
54.
We show that MapReduce, the de facto standard for large scale data-intensive parallel programming, can be equipped with a programming theory in calculational form. By integrating the generate-and-test programming paradigm and semirings for aggregation of results, we propose a novel parallel programming framework for MapReduce. The framework consists of two important calculation theorems: the shortcut fusion theorem of semiring homomorphisms bridges the gap between specifications and efficient implementations, and the filter-embedding theorem helps to develop parallel programs in a systematic and incremental way.  相似文献   
55.
We investigated the effects of esaxerenone, a novel, nonsteroidal, and selective mineralocorticoid receptor blocker, on cardiac function in Dahl salt-sensitive (DSS) rats. We provided 6-week-old DSS rats a high-salt diet (HSD, 8% NaCl). Following six weeks of HSD feeding (establishment of cardiac hypertrophy), we divided the animals into the following two groups: HSD or HSD + esaxerenone (0.001%, w/w). In survival study, all HSD-fed animals died by 24 weeks of age, whereas the esaxerenone-treated HSD-fed animals showed significantly improved survival. We used the same protocol with a separate set of animals to evaluate the cardiac function by echocardiography after four weeks of treatment. The results showed that HSD-fed animals developed cardiac dysfunction as evidenced by reduced stroke volume, ejection fraction, and cardiac output. Importantly, esaxerenone treatment decreased the worsening of cardiac dysfunction concomitant with a significantly reduced level of systolic blood pressure. In addition, treatment with esaxerenone in HSD-fed DSS rats caused a reduced level of cardiac remodeling as well as fibrosis. Furthermore, inflammation and oxidative stress were significantly reduced. These data indicate that esaxerenone has the potential to mitigate cardiac dysfunction in salt-induced myocardial injury in rats.  相似文献   
56.
Effect of the fatty acid composition of monoglycerides and shear on the polymorphic behavior in a water-in-oil (W/O) emulsion semi-solid fats blend was investigated. The bulk fat blend and the W/O emulsion fat blend with added either unsaturated or saturated monoglycerides were prepared using a rapid cooling heat exchanger, and the polymorphic transitions from β′ to β-form during storage were compared by X-ray diffraction. The peak intensity of the β-polymorph of the samples with added saturated monoglycerides was stronger than that of unsaturated monoglycerides, and the peak intensity of the β-polymorph of the W/O fat blend emulsions was stronger than that of the bulk fat blends. The polymorphic transition to the β-form during storage of the W/O emulsion fat blend was promoted by the applied shear. In contrast, that of the bulk fat blend was retarded by shear. These results suggested that fatty acids, which combined to monoglycerides on the surface of water droplets, influenced the polymorph transformation of the fat crystal network in a continuous semi-solid fat phase because of the acyl–acyl interactions between the fatty acid residues of the monoglycerides and triacylglycerols in the fat crystal network.  相似文献   
57.
Photooxidative Stability of Ice Cream Prepared from Milk Fat   总被引:2,自引:0,他引:2  
M. Shiota    N. Ikeda    H. Konishi    T. Yoshioka 《Journal of food science》2002,67(3):1200-1207
ABSTRACT: :
The photooxidation of ice cream containing 14.25% milk fat prepared from 7 fat materials with different compositions was investigated by conducting sensory evaluations for oxidized off-flavor and by monitoring hydroperoxide formation. They showed a wide range of oxidative stability against light, and the flavor score was related to peroxide value (correlation coefficient, 0.795). The photooxidative stability of ice cream was influenced mainly by the riboflavin content and by the oil's susceptibility to photooxidation. These contributing proportions were 53.7 and 17.6%, respectively, with a multiple regression model. The photooxidative stability of the oil fraction increased with the increasing tocopherol homologues ratio, γ-tocopherol/α-tocopherol (correlation coefficient, 0.846). Furthermore, the photooxidative stability of ice cream was influenced by the amount of free-fat content.  相似文献   
58.
Nonlinear image filtering with edge and corner enhancement   总被引:14,自引:0,他引:14  
The authors describe a model of nonlinear image filtering for noise reduction and edge enhancement using anisotropic diffusion. The method is designed to enhance not only edges, but corners and T junctions as well. The method roughly corresponds to a nonlinear diffusion process with backward heat flow across the strong edges. Such a process is ill posed, making the results depend strongly on how the algorithm differs from the diffusion process. Two ways of modifying the equations using simulations on a variable grid are studied  相似文献   
59.
On the basis of the latest achievements in anesthesia and reanimation, as well as the results of special military medical exercises and documents which depict the experience of local wars, the article shows the basic features of a conception about field anesthesia and reanimation. Taking into account the experience gained in Afghanistan the author determines the principles of its organization and approaches towards the solution of important tasks assigned to anesthesiological and reanimation service in combat conditions.  相似文献   
60.
Mammalian hairy and Enhancer of split homolog-1 (HES-1) encodes a helix-loop-helix (HLH) factor that is thought to act as a negative regulator of neurogenesis. To directly investigate the functions of HES-1 in mammalian embryogenesis, we performed a targeted disruption of the HES-1 locus. Mice homozygous for the mutation exhibited severe neurulation defects and died during gestation or just after birth. In the developing brain of HES-1-null embryos, expression of the neural differentiation factor Mash-1 and other neural HLH factors was up-regulated and postmitotic neurons appeared prematurely. These results suggest that HES-1 normally controls the proper timing of neurogenesis and regulates neural tube morphogenesis.  相似文献   
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