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排序方式: 共有484条查询结果,搜索用时 15 毫秒
81.
Haga S Fujimoto S Yonezawa T Yoshioka K Shingu H Kobayashi Y Takahashi T Otani Y Katoh K Obara Y 《Journal of dairy science》2008,91(8):3156-3164
The objective of the present study was to describe plasma hormonal and metabolite profile and mRNA expression levels and activities of the enzymes pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK), and acetyl-coenzyme A (CoA) carboxylase in the liver of male Holstein calves before (1 and 3 wk of age) and after (8, 13, and 19 wk of age) weaning at 6 wk of age. The mean plasma concentration of acetate and β-hydroxybutyrate increased, and that of plasma lactate and nonesterified fatty acids decreased with week, particularly after weaning. Plasma glucose concentration was lowest at 8 wk of age. The mean plasma concentration of insulin and glucagon did not change with time, and that of cortisol was greatest at 1 wk of age. In the liver, enzyme activity of PC was greatest at 1 wk of age and decreased with time. There was a significant relationship between the activity and the mRNA level for PC. Activity of PEPCK also decreased with week. Acetyl-CoA carboxylase activity tended to decrease with week, and activity at 13 wk of age was lower than that at other times. Expression of PC mRNA, but not that of PEPCK and acetyl-CoA carboxylase α, decreased with week. We conclude that the hepatic gluconeogenic enzymes and acetyl-CoA carboxylase activities tend to decrease with age, reflecting changes in plasma metabolites in early weaning production systems. 相似文献
82.
T Tsushima Y Katoh Y Miyachi K Chihara A Teramoto M Irie Y Hashimoto 《Canadian Metallurgical Quarterly》1999,84(1):317-322
Several GH isoforms have been identified in pituitary and serum, the most abundant of which is the 22K human GH (hGH) isoform. The 20K hGH isoform is produced by alternative splicing of GH messenger ribonucleic acid and comprises approximately 10% of all GH in the pituitary. The physiological role of 20K hGH remains to be determined, partly because of the lack of a simple and specific assay. We have established sensitive enzyme-linked immunosorbent assays (ELISAs) specific to 20K and 22K hGH. To determine whether regulation of 20K hGH secretion is the same as that for 22K hGH, we measured serum concentrations of both species of hGH in normal subjects and patients with a variety of endocrine disorders. The serum levels of 20K hGH after overnight fasting was 118 +/- 178 pg/mL (n = 282) in normal women, significantly higher than that in normal men (64 +/- 170 pg/mL; n = 226). However, there was no difference in the proportion of 20K hGH to 20K plus 22K hGH between men (6.3 +/- 2.6%, mean +/- SD; n = 176) and women (6.3 +/- 2.1%; n = 263). No correlation was detected between the ratio of 20K hGH and age, body height, body weight, or body fat mass in normal subjects. The proportion of 20K hGH was significantly (P < 0.001) higher in patients with active acromegaly (9.2 +/- 2.2%; n = 33) and patients with anorexia nervosa (9.0 +/- 1.9; n = 8), both of which are characterized by chronic elevation of circulating GH levels. The proportion of 20K hGH in successfully treated acromegalic patients did not differ from that in normal subjects, suggesting that GH-producing pituitary tumors secrete a higher proportion of 20K hGH, or that a chronic excess of 22K hGH alters the MCR of 20K hGH. The values in patients with adult GH deficiency, hyperthyroidism, primary hypothyroidism, or GH-independent short stature did not differ from those in normal subjects. The 20K ratio did not change after acute GH provocative tests, such as the insulin tolerance test and the GHRH test. These results suggest that secretion of 20K hGH from the pituitary is under the same control as that of 22K hGH. This new assay may provide a tool for understanding the physiological or pathophysiological role of the 20K hGH isoform. 相似文献
83.
为解决抚顺石化公司石油三厂连续重整装置原料短缺的问题,根据实际的工况条件,在小型试验装置上详细研究了大庆常压塔顶汽油脱砷脱氯工艺技术的可行性,并对几种脱砷脱氯工艺方案进行了论证。试验结果表明,通过对现有脱氯反应器的改造,采用脱砷-脱氯联合工艺技术,可将大庆常压塔顶汽油中的砷从1000ng/g以上脱除至10ng/g以下,氯从5μg/g以上脱除至0.5μg/g以下,循环气中的HCl小于1μg/g,完全满足连续重整装置工况的要求。对脱砷-加氢-脱氯汽油中碱金属和碱土金属的测定结果表明,不存在催化剂的金属流失问题。预计该工艺可为企业带来直接经济效益560万元/a。 相似文献
84.
Tamaki Shibayama Guo Wei He Heishichiro Takahashi Yutai Katoh Akira Kohyama 《北京科技大学学报(英文版)》1999,6(2)
LowZmaterialshavemanyadvantagesinnuclearenvirOInnellts,suchaslessProductionofradioactivewastesduetosubstantiallylowactivation,andhigherconVergentefficiencyduetothecapabilityofhightemp~OPeration.HopkinhasdiscussedSiC-basedmaterialsforfhaionreactorsfor... 相似文献
85.
S Matsuoka Y Ushiroguchi M Kubo K Tatara T Kitagawa I Katoh Y Kuroda 《Canadian Metallurgical Quarterly》1993,34(5):643-651
Balloon pulmonary valvuloplasty was performed in 3 infants with severe tetralogy of Fallot at days 24, 54 and 86 because of progressive hypoxemia. In two patients, the balloon catheter (4 cm long, 5-8 mm diameter) could not pass through the pulmonary valve. This necessitated a smaller balloon and required a two-step procedure. Initially, a coronary artery balloon (2 cm long, 3.5 mm diameter) was used. Following balloon valvuloplasty, arterial oxygen saturation increased from 63 to 83% in case 1, from 69 to 85% in case 2 and 63 to 86% in case 3. Immediate postvalvuloplasty right ventricular cineangiography revealed that the maximal opening diameter of the pulmonary valve leaflets increased from 1-2 mm to 3-4 mm in cases 1 and 3, and from 2-3 mm to 4-5 mm in case 2. No significant complications occurred. Echocardiographic follow-up data showed that the diameter of the right ventricular outflow tract and pulmonary arteries increased with age. The present results show that the pulmonary valvuloplasty is an effective procedure for relief of pulmonary valve stenosis in tetralogy of Fallot and to improve oxygenation and growth of the pulmonary arteries and right ventricular outflow tract without the need of an immediate aortopulmonary shunt. 相似文献
86.
Toshihide Ibaraki Yoshiroh Katoh 《Annals of Mathematics and Artificial Intelligence》1990,1(1-4):141-153
Games such as CHESS, GO and OTHELLO can be represented by minimax game trees. Among various search procedures to solve such game trees,- and SSS* are perhaps most well known. Although it is proved that SSS* explores only a subset of the nodes explored by-, - is commonly believed to be faster in real applications, since it requires very little memory space and hence its storage management cost is low. Contrary to this folklore, however, this paper reports, using the OTHELLO game as an example, that SSS* is much faster than-. It is also demonstrated that SSS* can be modified to make the required memory space controllable to some extent, while retaining the high efficiency of the original SSS*.This research was partially supported by the Ministry of Education, Science and Culture of Japan, under a Scientific Grant-in-Aid. 相似文献
87.
Isao Kobayashi Sayumi Hirose Takanori Katoh Yanping Zhang Kunihiko Uemura Mitsutoshi Nakajima 《Microsystem Technologies》2008,14(9-11):1349-1357
Microchannel (MC) emulsification is a promising technique for producing monodisperse emulsions consisting of highly uniform droplets. The authors developed a high-aspect-ratio microstructure (HARMST) made of poly(methyl methacrylate) (PMMA) as a new MC emulsification device. A PMMA straight-through MC array plate consisting of 31,250 through-holes with a 7.3 × 22.9-μm oblong section and a 200-μm depth was fabricated by a process of synchrotron radiation (SR) lithography and etching. Oblong MCs fabricated in a PMMA straight-through MC array were highly uniform with a coefficient of variation of less than 2%. The fabricated PMMA straight-through MC array plate was used to produce water-in-oil (W/O) emulsions. Monodisperse W/O emulsions with average droplet diameters of approximately 25 μm and a minimum coefficient of variation of 3.2% were produced via a hydrophobic PMMA straight-through MC array. The PMMA straight-through MC array plate also produced monodisperse W/O emulsions at droplet production rates of up to 1.7 × 104/s. The PMMA straight-through MC array plates developed in this work are expected to expand the application field of emulsification using straight-through MC array plates, which have previously been made of single-crystal silicon. 相似文献
88.
Seong-Gu Hong Thak-Sang Byun Richard A. Lowden Lance L. Snead Yutai Katoh 《Journal of the American Ceramic Society》2007,90(1):184-191
A program to develop new methods to measure the fracture strength of the chemical vapor deposition SiC coatings in nuclear fuel particles has been carried out. Internal pressurization and crush test techniques were developed and applied to prototype-sized tubular and hemispherical shell specimens. The fracture strength measured from each test method applying the Weibull two-parameter distribution, and Weibull parameters were measured. It was shown that data generated with each test technique were independent of the test technique applied. This implies that the developed test methods are reliable and provide reasonable strength data. For the same material, fracture strength varied with the specimen geometry and loading configuration. These size and loading configuration effects on the fracture strength are explained with the concept of effective surface. 相似文献
89.
Banded structure and its distribution in friction stir processing of 316L austenitic stainless steel
Y.C. Chen H. Fujii T. Tsumura Y. Kitagawa K. Nakata K. Ikeuchi K. Matsubayashi Y. Michishita Y. Fujiya J. Katoh 《Journal of Nuclear Materials》2012,420(1-3):497-500
Banded structures, which vary with welding parameters, were observed in friction stir processing of 316L austenite stainless steel. Sigma phase precipitation was detected in banded structures by transmission electron microscopy. The amount of banded structure had direct ratio relations with heat input. The higher the heat input, the larger the area of banded structures. This is attributable to slower cooling rate at high heat input, which results in longer exposure to the temperature range for precipitation. The formation of sigma phase produced Cr depletion, which resulted in largely degraded corrosion resistance. The present study suggests that low heat input (i.e. low rotation speeds, low working loads and high welding speed) contributes to restrain sigma phase precipitation. 相似文献
90.
AbstractSolvent extracts were compared with the parent gelatins by means of TLC and HPLC. The photographic effects of the various protein fractions are discussed. 相似文献