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1.
Desulfurization of model and diesel oils by resting cells of Gordona sp.   总被引:2,自引:0,他引:2  
The desulfurization activity of the resting cells of Gordona sp. CYKS1 was strongly depended on harvest time and the highest value when the cells had been harvested in the early growth phase (0.12 mg sulfur g–1 cell–1 h–1). For the model oil, hexadecane containing dibenzothiophene, the specific desulfurization rate decreased as the reaction proceeded. Both the specific and the volumetric desulfurization rates were not significantly affected by the aqueous-to-oil phase ratio. The diesel oils, light gas oil and a middle distillate unit feed were desulfurized at higher rates (ca. 0.34 mg sulfur g–1 cell–1 h–1) than the model oil (0.12 mg sulfur g–1 cell–1 h–1).  相似文献   
2.
As nutritional status and inflammation are strongly connected, feeding and nutritional strategies could be effective to improve the ability of pigs to cope with disease. The aims of this study were to investigate the impact of a feed restriction on the ability of pigs to resist and be tolerant to a coinfection with Mycoplasma hyopneumoniae (Mhp) and the European H1N1 swine influenza virus, and the consequences for nutrient metabolism, with a focus on amino acids. Two groups of specific pathogen-free pigs were inoculated with Mhp and H1N1 21 days apart. One group was fed ad libitum, the other group was subjected to a two-week 40% feed restriction starting one week before H1N1 infection. The two respective mock control groups were included. Three days post-H1N1 infection, 200 g of feed was given to pigs previously fasted overnight and serial blood samples were taken over 4 hours to measure plasma nutrient concentrations. Throughout the study, clinical signs were observed and pathogens were detected in nasal swabs and lung tissues. Feed-restricted pigs presented shorter hyperthermia and a positive mean weight gain over the 3 days post-H1N1 infection whereas animals fed ad libitum lost weight. Both infection and feed restriction reduced postprandial glucose concentrations, indicating changes in glucose metabolism. Post-prandial plasma concentrations of the essential amino acids histidine, arginine and threonine were lower in co-infected pigs suggesting a greater use of those amino acids for metabolic purposes associated with the immune response. Altogether, these results indicate that modifying feeding practices could help to prepare animals to overcome an influenza infection. Connections with metabolism changes are discussed.  相似文献   
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Addition of a thermostable cytoplasmic fraction leads to the uncoupling of oxidative phosphorylation of the mitochondria. In hyperthyrosis such an effect manifests itself more powerfully than in the control. Addition of the thermostable cytoplasmic fraction induces electrogenic phosphate transport via the mitochondrial membrane. In hyperthyrosis, the activity of the thermostable inducer of phosphate transport in the cytoplasm increases. The functioning of the phosphate cycle may be the cause of the uncoupling of oxidative phosphorylation of the mitochondria during the disease in question.  相似文献   
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G Gaál  E Bácsy  G Rappay 《Histochemistry》1988,88(3-6):401-406
Cultured cells from the anterior pituitary glands of adult rats were treated with the tripeptide aldehyde proteinase inhibitor, BOC-DPhe-Phe-Lys-H. The addition of this tripeptide aldehyde decreased the in vitro release of prolactin to 25% of the control value, while the release of growth hormone in the same cultures decreased to 33% of the control value. Prolactin immunostaining was stronger in semithin sections of proteinase-inhibitor-treated cultures than in control sections. After 2 h treatment with the inhibitor, prolactin- and growth hormone-containing secretory granules were numerous, and the number of crinophagic vacuoles had increased. In the presence of the inhibitor, the overall cytoarchitecture of parenchymal cells was well preserved, and the pathway of the uptake of cationic ferritin appeared to be unaffected.  相似文献   
7.
According to the generally accepted theory of mammalian cochlear mechanics, the fluid in the cochlear scalae interacts with the elastic cochlear partition to generate transversely oscillating displacement waves that propagate along the cochlear coil. Using a computational model of cochlear segments, a different type of propagating wave is reported, an elastic propagating wave that is independent of the fluid-structure interaction. The characteristics of the propagating wave observed in the model, such as the wavelength, speed, and phase lag, are similar to those observed in the living cochlea. Three conditions are required for the existence of the elastic propagating wave in the cochlear partition without fluid-interaction: 1), the stiffness gradient of the cochlear partition; 2), the elastic longitudinal coupling; and 3), the Y-shaped structure in the organ of Corti formed by the outer hair cell, the Deiters cell, and the Deiters cell phalangeal process. The elastic propagating waves in the cochlear partition disappeared without the push-pull action provided by the outer hair cell and Deiters cell phalangeal process. The results suggest that the mechanical feedback of outer hair cells, facilitated by the organ of Corti microstructure, can control the tuning and amplification by modulating the cochlear traveling wave.  相似文献   
8.
Kinetics of monoamine oxidase (MAO) catalyzed dehydrogenation of neurotropic analogues of biogenic monoamines in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine series were studied. It is shown that methyl substitution in the phenyl ring increases significantly the enzyme-substrate affinity, but the substituent's effect on the catalytic stage largely depends upon its position in the ring. o- and m-Methyl derivatives were preferably oxidized by B type of MAO, whereas p-total derivative was oxidized by B type as well as by A type of the enzyme. In the course of the oxidation reactions MAO is irreversibly inhibited by the dihydropyridinium product of the reaction, particularly in case of methyl derivatives. The significant and structure-dependent inhibition of the enzyme might be responsible for the differences in neurotropic properties of the above substrate homologues.  相似文献   
9.
Peculiarities of cytoskeleton in membranous cells and disposition of the latter in the cupola epithelium in aggregated lymphoid nodules++ (ALN) have been studied in the ileum of 5 rabbits. The material has been fixed in liquid nitrogen and in the mixture of paraformaldehyde and glutar aldehyde. Methods of immunomorphology, high resolving light and transmissive electron microscopy have been used. Monoclonal antibodies to vimentin are selectively bind with a specific population of the ALN cupola epithelial cells. These cells are regularly arranged in the epithelium of the cupola lateral part and they are absent in the epithelium of the intestinal crypts, villi and apex of the cupolas. In the lateral epithelium of the cupolas surface, nearer to their base vimentin-positive++ epitheliocytes make contacts with single interepitheliocytic lymphocytes, and nearer to the apex they surround compact groups of the interepitheliocytic lymphocytes. The vimentin-positive++ epitheliocytic cells are identified as M-cells.  相似文献   
10.
Prevalence rates (PRs) for EFP (schizophrenic, schizoaffective and affective psychoses), with allowance for proband sex and age-of-onset data were studied in a subdivided population from the North-East of the European Region of the USSR. The population includes three subpopulations: a small old religious semi-isolate of Russians ("Rs"), aboriginal Komi people ("Ks")--an ethnic community of Ugro-Finnish lineage, and a mixed group of migrants ("Ms") from various regions of the USSR. The latter is mainly an urban population, while the "Rs" and "Ks" are, on the whole, rural populations. The total PR for EFP was found to be 0.97% for the "Rs", 0.63% for the "Ks" and 0.35% for the "Ms", whereas PRs-0.85-1.15% in other parts of the USSR, mainly for "panmixed" populations in large towns. The lower PRs for EFP in the "Ms" is caused by a backmigration flow involving certain groups of patients; consequently, the mean liability for "Ms" offsprings (as a whole) should also be lower. On the other hand, the lower PRs for EFP in the "Ks" is caused by underpresentation of clinically mild cases of the mental disease (mainly, pseudoneurotic schizophrenia), especially among female patients, probably due to that the so affected persons are sufficiently adapted to the cultural traditions of this rural population. It was shown that in the "Rs" the total PR for "nuclear" and paranoid schizophrenia is 0.68% versus 0.25% in a "panmixed" population. The increase is most likely caused by the high inbreeding level in the "Rs" semi-isolate, and if this is correct, we may suppose that at least one or two recessive genes are involved in the liability to the most heavy forms of schizophrenia. On the other hand, in the "Ms" (as in other "panmixed" populations) positive assortative mating among hereditary-predisposed persons is a more significant factor influencing family transmission of EFP, since the correlation between probands and their spouses is rpp = 0.31 (p less than 0.001) in the "Ms", as compared to rpp = 0.19 (p less than 0.1) in the "Rs". Thus, our general conclusion is that neither the place of inhabitance nor the life mode are the causal factors for EFP, but rather some genetic factors, more accurately, certain sets of specific genes.  相似文献   
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