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161.
The efficacy of percutaneous elcatonin (EC), a hypocalcemic peptide, in the treatment of experimental osteoporosis in rats was evaluated in vivo. Additionally, the effect of the combined use of EC and active vitamin D3 (1,25(OH)2D3) for the treatment was compared with those of three other groups: 1,25(OH)2D3 alone, estradiol plus 1,25(OH)2D3, and a placebo, and low calcium diet (low Ca). The EC transdermal system and the EC plus 1,25(OH)2D3 system, applied to the rat abdominal skin 6 times for 48 h, significantly increased the ash weight and calcium content of the tibia in the rats, compared with those of placebo group (p < 0.05). The EC systems also slightly lowered the alkaline phosphatase activity in plasma of the morbid rats, without a difference in the plasma calcium content. These EC systems were superior to the 1,25(OH)2D3 system and the estradiol plus 1,25(OH)2D3 system in improving osteoporotic parameters. Thus, the EC systems were concluded to be an efficient drug delivery system for Paget's disease and osteoporosis. 相似文献
162.
Recent studies have reported that tranilast inhibited in vitro the proliferation of keratocytes from corneal subepithelial opacities (haze) and collagen synthesis in cultured corneas after excimer laser photorefractive keratectomy (PRK). In this study 0.5% tranilast eye drops, 0.1% betametazone phosphate eyedrops, and a 0.5% tranilast base solution (control) were administered four times daily to rabbits which had undergone PRK. Weekly evaluation of the inhibitory effect of these drugs on haze began two weeks after surgery according to Fantes' classification. 0.5% tranilast suppressed haze from six weeks to thirteen weeks after PRK (p < 0.05). 0.1% betametazone phosphate showed no effect. These results suggested that 0.5% tranilast had a satisfactory therapeutic effect on haze after PRK. 相似文献
163.
The activities of key enzymes in glycerolipid biosynthesis and fatty acid oxidation were compared using CoA esters of naturally
occurring positional isomers of octadecatrienoic acids (18∶3) as the substrates. The trienoic acids employed were 9,12,15–18∶3
(α-18∶3), 6,9,12–18∶3 (γ-18∶3), and 5,9,12–18∶3 (pinolenic acid which is a fatty acid contained in pine seed oil, po-18∶3).
The activities of microsomal glycerol 3-phosphate acyltransferase obtained with various 18∶3 were only slightly lower than
or comparable with those obtained with palmitic (16∶0), oleic (18∶1), and linoleic (18∶2) acids. Mitochondrial glycerol 3-phosphate
acyltransferase was exclusively specific for saturated fatty acyl-CoA. The activities of microsomal diacylglycerol acyltransferase
measured with various polyunsaturated fatty acyl-CoAs were significantly lower than those obtained with 16∶0- and 18∶1-CoAs.
Among the polyunsaturated fatty acids, γ-18∶3 gave the distinctly low activity. The Vmax values of the mitochondrial carnitine palmitoyltransferase I were significantly higher with α-18∶3 and po-18∶3 but not γ-18∶3,
than with 16∶0 and 18∶2, while the apparent Km values were the same irrespective of the types of acyl-CoA used except for the distinctly low value obtained with γ-18∶3.
The response to an inhibitor of the acyltransferase reaction, malonyl-CoA, was appreciably exaggerated with 18∶2, α-18∶3,
and po-18∶3 more than with 16∶0 and 18∶1. However, the response with γ-18∶3 was the same as with 16∶0. Thus, some of glycerolipid
biosynthesis and fatty acid oxidation enzymes could discriminate not only the differences in the degree of unsaturation of
fatty acids but also the positional distribution of double bond among the naturally occurring 18∶3 acids. 相似文献
164.
For three weeks, male Sprague-Dawley rats at either four weeks (young) or eight months (adult) of age were pairfed one of
the purified diets free of or containing either 0.2% of oxidized cholesterol mixture (cholesterol oxidation products) or 0.2%
of cholesterol. Although the food intake was similar, dietary oxidized cholesterol lowered body weight gain in young rats,
but did not increase relative liver weight, in contrast to the enlargement seen with dietary cholesterol. Oxidized cholesterol,
compared to cholesterol, tended to reduce the activity of hepatic 3-hydroxy-3-methylglutaryl CoA reductase and cholesterol
7α-hydroxylase, particularly the latter in aged rats, and prevented the rise in the concentration of liver cholesterol at
both ages. It also tended to increase the activity of hepatic δ6 desaturase, particularly in young rats. Moreover, oxidized
cholesterol in relation to cholesterol influenced liver and serum lipid concentrations in different ways, and increased lipid
peroxidation at both ages. The ratio of splenic CD4+/CD8+ T-lymphocytes increased with age, but the influence of cholesterol and oxidized cholesterol was comparable. Thus, oxidized
cholesterol may specifically disturb growth and age-related changes in the lipid metabolism in rats. 相似文献
165.
Fumiyuki Fujii Masaru Ishii Mikihisa Saito Michihiro Matsui Daisuke Natsuno 《Electrical Engineering in Japan》2013,184(2):44-50
Wind turbines on the coast of the Sea of Japan have been damaged by lightning in winter. This is due to the frequent occurrence of upward lightning from wind turbines in winter. Occurrence of upward lightning proves to be closely related to the temperature distribution at high altitudes. In this paper, the correlation between lightning hits of wind turbines and the height of the—10 °C layer is analyzed. When an upward lightning hits a wind turbine in winter, the height of the—10 °C layer is lower than 2000 m in most cases. Moreover, winter lightning is classified into two types, namely, the storm type and the inactive type, and it is found that the parameters of lightning currents observed by LLS differ depending on the type of lightning storm. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(2): 44–50, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22357 相似文献
166.
167.
The introduction of superplasticizer (Sp) has produced concrete that could flow easily under its own weight. In balancing the concrete's ability to flow at the same time maintaining the coarse aggregate distribution, the viscosity of concrete must be enhanced. This study aimed to investigate the effect of vibration on such flowable yet viscous concrete. Concrete flowability and viscosity are quantified by the standard slump cone and V-funnel test, respectively. Despite being flowable, the study concluded that concrete viscosity is an important parameter in determining the tendency for coarse aggregates to segregate. Large-sized coarse aggregates are affected more by the vibration process than the small-sized ones. 相似文献
168.
The preparation of a three-dimensionally (3D) ordered macroporous iron-platinum (FePt) film derived from monodisperse FePt nanoparticles (approximately 3 nm in diameter) and polystyrene latex particles (254 nm in diameter) is described. The prepared film has a hexagonally ordered porous structure and coercivity up to 10 kOe after annealing at a temperature of 600 degrees C. We also found that size of FePt particles was maintained at around 3 nm, even after annealing at a temperature of 600 degrees C. 相似文献
169.
Woelke A Imanaka S Watanabe S Goto S Hashinokuchi M Okada M Kasai T 《Journal of electron microscopy》2005,54(Z1):i21-i24
Chemical reactions of methyl chloride (CH3Cl) on a clean Si(001) surface at approximately 300 K are studied by means of scanning tunneling microscopy (STM) under ultra-high-vacuum conditions. The features appearing in the STM images are identified with the possible products of dissociated CH3 and Cl, and their distribution is also evaluated as well as the development of their distribution with increasing CH(3)Cl doses. The amount of Cl atoms found on the surface is approximately twice as large as that of the CH3 molecules. This leads to the conclusion that dissociative adsorption of CH3Cl on Si occurs in different processes: CH3Cl(precursor) --> CH3(ad) + Cl(ad) and CH3Cl(precursor) --> CH3(gas) + Cl(ad). 相似文献
170.
Species and muscle differences in L-carnitine levels in skeletal muscles based on a new simple assay 总被引:1,自引:0,他引:1
Shimada K Sakuma Y Wakamatsu J Fukushima M Sekikawa M Kuchida K Mikami M 《Meat science》2004,68(3):357-362
We have adapted the enzymatic method [Biochemical and Biophysical Research Communications 176 (3) (1991) 1617] for the safe and rapid assay of L-carnitine (L-CA) in skeletal muscle using a microplate reader. The concentration of L-CA in fresh semitendinosus muscle from broiler chicken, pig, beef cattle, deer, horse and goat muscle were 0.69, 1.09, 1.86-3.57, 4.57, 4.95 and 11.36 μmol/g wet weight, respectively. The animals which had higher concentration of L-CA, also had the highest amounts of myoglobin as an index to the redness of the muscle. Furthermore, we investigated this relationship between white muscle, M. pectoralis profundus, and red muscle, M. soleus, in laying hens. The L-CA and myoglobin concentration in red muscle were significantly higher than those in white muscle (p<0.01). These findings suggest that L-CA concentration in muscle is related to oxygen metabolism and to myofiber types. 相似文献