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After intravenous (i.v.) infusion of various volumes of 1.35%-isotonic sodium bicarbonate solution (ISB), acid-base equilibrium, blood pressure, plasma volume and biochemical parameters in healthy Holstein calves were studied. Four calves each were randomly assigned to the low-dose (LD; i.v. infusion of 5 ml/kg ISB), middle-dose (MD; i.v. infusion of 10 ml/kg ISB) and the high-dose groups (HD; i.v. infusion of 15 ml/kg ISB). Administration volumes of ISB in the LD, MD and HD groups were decided based on the first half volumes of 5, 10 and 15 mEq of base requirement by the acceptable equation. Systemic, pulmonary artery and central venous pressures, cardiac output and plasma osmotic pressure were not changed by ISB infusion and remained constant throughout the experiment for all groups. There was good correlation (r(2) = 0.950) between relative changes in base excess and infused volume of bicarbonate (y=2.491x). The coefficient of distribution for bicarbonate ions was calculated to be 0.401 (=1/2.491). Therefore, it is suggested that a value of 0.4 would be most appropriate when calculating the base requirements in calves. Therefore, the first half volumes of ISB correcting base deficits of 5, 10 and 15 mEq in calves were estimated to be 6, 12 and 18 ml/kg, respectively. On the basis of the findings in this study, ISB may be used to correct metabolic acidosis without altering the plasma osmotic pressure, hemodynamic status and respiratory function in the calves.  相似文献   
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CO2 concentration in a marine phytoplankton, Nannochloropsis sp., culture medium was observed to consider whether or not CO2 defficiency for growth occurs in the culture medium of a mass culture. In the first experiment, the Nannochloropsis sp. culture was continued for 4–5 days and the CO2 concentration was observed three times a day, namely, the initial, middle and end of the light period. While, in the second experiment, the CO2 concentration was observed every 2–3 hr for 24 hr on the second day after inoculation. In the first experiment, the total CO2 concentration decreased gradually throughout the culture period, repeating its decrease and increase in the light and dark periods, respectively. At the end of the light period of the third day after inoculation, the CO2 concentration decreased to concentrations which could not be determined. In the second experiment, the CO2 concentration decreased in the light period, and increased in the dark period. The increment in the dark period was faster at heavier aeration. It was considered that some kind of carbon source should be supplied to obtain high density of Nannochloropsis sp. ealier under strong light intensity.  相似文献   
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The objective of the present study was to examine the relationship between plasma leptin levels and fat distribution in crossbred steers. Twenty-four crossbred steers (Japanese Black × Holstein) were used in this study. Six steers belonged to the growing phase (11 months of age), and 18 steers to the finishing phase (from 21 to 28 months of age). Plasma leptin levels correlated positively with body fat weight ( r  = 0.807, P  < 0.01), body fat percentage ( r  = 0.802, P  < 0.01), visceral fat weight ( r  = 0.807, P  < 0.01), visceral fat percentage ( r  = 0.780, P  < 0.01), subcutaneous fat weight ( r  = 0.745, P  < 0.01), subcutaneous fat percentage ( r  = 0.734, P  < 0.01), intermuscular fat weight ( r  = 0.793, P  < 0.01), intermuscular fat percentage (0.775, P  < 0.01), renal fat weight ( r  = 0.694, P  < 0.01), renal fat percentage ( r  = 0.642, P  < 0.01), subcutaneous fat thickness ( r  = 0.755, P  < 0.01), intermuscular fat thickness ( r  = 0.721, P  < 0.01), beef marbling score ( r  = 0.706, P  < 0.01) and the crude fat content of Musculus longissimus thoracis ( r  = 0.592, P  < 0.01). The location of fat deposits did not affect the correlation values. However, when steers were divided into growing ( n  = 6) and finishing ( n  = 18) groups, there was no significant correlation between plasma leptin levels and the carcass characteristics related to fat deposition (fat weight, fat percentage, carcass traits) in either group. These results suggest that plasma leptin levels in crossbred steers positively correlate with body fat content and carcass traits when these parameters vary widely.  相似文献   
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Sugi (Cryptomeria japonlca D. Don) wood powder was carbonized at varying temperatures by a onestep process up to 1000C and a two-step process using wood charcoal as the raw material up to 1600C. This study was conducted to evaluate the adsorptive properties of wood charcoal and discuss the mechanism of its adsorptive function in relation to the physical and anatomical characteristics of wood after carbonization. Anatomical characteristics of carbonized wood materials were directly observed under heating using an environmental scanning electron microscope (ESEM); the cell wall structures were analyzed by high-resolution transmission electron microscope (HRTEM). The largest weight losses were observed at the highest temperatures, in both the one-step and twostep processes but leveled off above 800C. Shrinkages in the tangential, radial, and longitudinal directions increased with carbonization temperature, peaking at 1000C. Direct observations by ESEM showed distinct shrinkage at around 400C. The first trial observations by HRTEM on the changes in the ultrastructure of cell walls of wood charcoals were done, and it was assumed to affect the formation of micropores. Adsorption was found to follow the Langmuir isotherm model. With the one-step carbonization process, the iodine adsorption capacities of the carbonized wood powders increased with increasing carbonization temperature, peaking at 800C, but decreased at higher temperatures. The wood powder carbonized at 1000C with the two-step process showed the highest capacity, but further heating up to 1400C drastically decreased the adsorption. The shrinkage of cells was related to the increases and decreases in its specific surface area. Specific surface area and total pore volume were evidently related to the adsorptive properties.Part of this paper was presented at the Second International Wood Science Seminar, Indonesia, November 6–7, 1998  相似文献   
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The ability of sugi wood carbonized at 1000°C to adsorb mercury was examined using aqueous solutions of mercuric chloride. Parameters studied include contact time, pH, adsorption temperature, and initial concentration of mercury in solution. Results showed that sugi wood carbonized at 1000°C could effectively remove mercury from aqueous solutions. The carbonized wood showed high adsorption ability for mercury at a wide pH range (pH 3–9), but its ability drastically decreased at pH 11. Adsorption decreased with increases in adsorption temperatures, indicating that the processes were exothermic in nature. Adsorption was found to follow the Freundlich isotherm model. The adsorption capacity of carbonized sugi wood was comparable to that of commercial activated carbon.  相似文献   
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Oxidative stress owing to an imbalance between reactive oxygen species and antioxidants, such as coenzyme Q10 (CoQ10), is a major contributor to male infertility. We investigated the effects of the reduced form of CoQ10 (ubiquinol) supplementation on semen quality in dogs with poor semen quality. Three dogs received 100 mg of ubiquinol orally once daily for 12 weeks. Semen quality, serum testosterone, and seminal plasma superoxide dismutase (SOD) activity were examined at 2-week intervals from 2 weeks before ubiquinol supplementation to 4 weeks after the treatment. Ubiquinol improved sperm motility, reduced morphologically abnormal sperm, and increased seminal plasma SOD activity; however, it had no effect on testosterone level, semen volume, and sperm number. Ubiquinol supplementation could be used as a non-endocrine therapy for infertile dogs.  相似文献   
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