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101.
Koshida S Urabe Y Miyashita K Iwai K Kagimori A 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(5):1584-1588
Previous studies have suggested that resistance training exercise under unstable conditions decreases the isometric force output, yet little is known about its influence on muscular outputs during dynamic movement. The objective of this study was to investigate the effect of an unstable condition on power, force, and velocity outputs during the bench press. Twenty male collegiate athletes (mean age, 21.3 +/- 1.5 years; mean height, 167.7 +/- 7.7 cm; mean weight, 75.9 +/- 17.5 kg) participated in this study. Each subject attempted 3 sets of single bench presses with 50% of 1 repetition maximum (1RM) under a stable condition with a flat bench and an unstable condition with a Swiss ball. Acceleration data were obtained with an accelerometer attached to the center of a barbell shaft, and peak outputs of power, force, and velocity were computed. Although significant loss of the peak outputs was found under the unstable condition (p < 0.017), their reduction rates remained relatively low, approximately 6% for force and 10% for power and velocity outputs, compared with previous findings. Such small reduction rates of muscular outputs may not compromise the training effect. Prospective studies are necessary to confirm whether the resistance training under an unstable condition permits the improvement of dynamic performance and trunk stability. 相似文献
102.
Akira Watanabe Shiro Yamaguchi Koichiro Urabe Yasuhiko Asada 《Journal of Molecular Catalysis .B, Enzymatic》2003,23(2-6):379
Free
-alanine was detected in a cell extract of the fruit-body of an edible basidiomycetous mushroom, Lentinus edodes (Shiitake), by means of reverse-phase high performance liquid chromatography. We also found an amino acid racemase activity in L. edodes fruit-body, and purified the enzyme. The enzyme has a molecular weight of approximately 86,000, and consists of two subunits of identical molecular weight (44,000). The optimal pH of the enzyme activity is around pH 9.5 for both
-to-
and
-to-
alanine racemization. The enzyme requires pyridoxal 5′-phosphate as a cofactor. Km and Vmax values for
-alanine were 37.3 mM and 520 nmol/min/mg, respectively; for
-alanine, they were 9.21 mM and 141 nmol/min/mg, respectively. The equilibrium constant was calculated to be 1.10, which is consistent with the theoretical value for the racemase reaction. The ability of the enzyme to catalyze the racemization of various
-amino acids was investigated. The enzyme catalyzes the racemization of
-serine (relative reaction rate, 144% of rate for
-alanine),
-alanine (100%),
-homoserine (17.1%),
-2-aminobutyrate (5.6%),
-glutamate (4.5%), and
-asparagine (3.2%). To the best of our knowledge, this is the first report of an amino acid racemase produced by a basidiomycetous mushroom. 相似文献
103.
Campos AH Aldred VL Ribeiro KC Vassallo J Soares FA 《Molecular and cellular biochemistry》2009,321(1-2):95-102
Hodgkin and Reed-Sternberg (H-RS) cells of classical Hodgkin lymphoma (cHL) present an impaired expression of immunoglobulin genes, but escape apoptotic death. We investigated whether nitric oxide synthases (NOS) are expressed by H-RS cells, studied their association with EBV status and the expression of apoptotic proteins, and investigated their relationship to the clinical outcome of 171 patients. NOS1 and NOS2 were expressed in a large number of cases, whereas NOS3 expression was not detected. Positive associations were found between NOS1 and p53, bax and NOS2, bcl-2 and NOS2, bax and p53, and between bax and fasL. Inverse correlations were established between EBV and NOS2 and between EBV and bcl-2. A shorter overall survival (OS) was associated with strong expression of NOS2. In conclusion, NOS are expressed by H-RS cells of cHL. 相似文献
104.
105.
Ken Urabe Kouji Naruse Masataka Uchino Masashi Takaso Mamoru Fujita Katsufumi Uchiyama Takamitsu Okada Midori Kasahara Moritoshi Itoman 《Cell and tissue banking》2009,10(3):259-265
Demand for banked bone allografts is increasing in Japan; however, there are too few bone banks and the bone bank network
is not well-established. One reason for this was lack of funding for banks. Bone banks had to bear all material expenses of
banked bone allografts themselves because this was not designated a covered expense. In December 2004, the Japanese government
started a new “Advanced Medical Treatment” administration system which allowed an approved institution to charge the expense
of authorized advanced medical treatments directly to patients. The treatment named “Cryopreserved allogenic bone and ligamentous
tissue retrieved from cadaveric donor” was approved as an advanced medical treatment in March 2007. We present the calculation
method and the expense per implantation of a banked bone allograft from a cadaveric donor under this treatment and raise issues
which affect this advanced medical treatment and remain to be resolved in the Japanese orthopaedic field. 相似文献
106.
Sumiyo Morita Akemi Hara Itaru Kojima Takuro Horii Mika Kimura Tadahiro Kitamura Takahiro Ochiya Katsumi Nakanishi Ryo Matoba Kenichi Matsubara Izuho Hatada 《PloS one》2009,4(1)
Dicer1, an essential component of RNA interference and the microRNA pathway, has many important roles in the morphogenesis of developing tissues. Dicer1 null mice have been reported to die at E7.5; therefore it is impossible to study its function in adult tissues. We previously reported that Dicer1-hypomorphic mice, whose Dicer1 expression was reduced to 20% in all tissues, were unexpectedly viable. Here we analyzed these mice to ascertain whether the down-regulation of Dicer1 expression has any influence on adult tissues. Interestingly, all tissues of adult (8–10 week old) Dicer1-hypomorphic mice were histologically normal except for the pancreas, whose development was normal at the fetal and neonatal stages; however, morphologic abnormalities in Dicer1-hypomorphic mice were detected after 4 weeks of age. This suggested that Dicer1 is important for maintaining the adult pancreas. 相似文献
107.
Kinoshita Y Saito M Satoh I Shomori K Suzuki H Yamada M Kono T Satoh K 《Life sciences》2006,78(13):1508-1514
Diabetic neuropathy, a major complication of diabetes mellitus, is associated with the development of vascular dysfunction and autonomic neuropathy. We studied the effects of cyclohexenonic long-chain fatty alcohol (FA) on streptozotocin-diabetic hyperreactivity in the rat aorta smooth muscle. The rats were divided randomly into four groups and were maintained for 4 weeks: age-matched control rats, diabetic rats without treatment with FA, and diabetic rats treated with FA (2 and 8 mg/kg, i.p. everyday). The serum glucose and insulin levels were determined, and the contractile responses of the aorta induced by a thromboxane A2 agonist, U46619 and KCl were investigated. Treatment with FA did not alter rats' diabetic status, i.e., body weight, thickness of the aorta, serum glucose levels, and serum insulin levels, but significantly improved the diabetic-induced hyperreactivity of the rat aorta in a dose-dependent manner. Removal of endothelium did not change contractile force between groups. In histological examinations, thinning of smooth muscle bundle in the wall of aorta was observed in the diabetic rat, which was not significantly improved by treatment with FA. Our data indicate that FA can prevent hyperreactivity in the diabetic aorta. 相似文献
108.
109.
110.
Hideyuki?Kawai Shigeya?NagayamaEmail author Hirokazu?Urabe Takumi?Akasaka Futoshi?Nakamura 《Environmental Biology of Fishes》2014,97(5):575-586
Recent studies have demonstrated that the energetic profitability (net energy intake potential; NEI potential) of a habitat, which is calculated as the gross energy gain from foraging minus the energy expenditure from swimming at a focal point, may be a useful tool for predicting the salmonid biomass. The effectiveness of the NEI potential should be tested in various systems. Even if the NEI potential is validated, its predictive accuracy and transferability could be limited if the cover habitat, which is known to be an important factor for determining salmonid abundance, is not considered. We tested whether the NEI potential is effective for predicting the salmonid biomass even in a stream with abundant cover and whether combining the NEI potential and cover effects can improve the predictability of fish biomass using a generalized linear model. Our results demonstrated that the NEI potential could generally predict the fish biomass (percent deviance explained?=?79.9 %), and the model that incorporated both the NEI potential and the cover ratio improved the predictive accuracy (percent deviance explained?=?88.5 %). These results suggest that energetic profitability can be an effective indicator for assessing habitat quality and is relatively transferable to other systems. Furthermore, when cover effects are considered, the habitat quality is more accurately represented; thus, combining the energetic profitability and the cover effects might improve the transferability of the assessment across habitats. 相似文献