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41.
R Ishisaka T Utsumi M Yabuki T Kanno T Furuno M Inoue K Utsumi 《Canadian Metallurgical Quarterly》1998,435(2-3):233-236
Apoptosis, a naturally occurring programmed cell death or cell 'suicide', has been paid much attention as one of the critical mechanisms for morphogenesis and tissue remodeling. Activation of cysteine aspartases (caspases) is one of the critical steps leading to apoptosis. Although a mitochondria-mediated pathway has been postulated to be one of the activation mechanism of caspase-3, another subcellular compartment might be involved in the activation of the enzyme. The present study shows that the supernatant fraction of digitonin-treated lysosomes strongly activates Ac-DEVD-CHO inhibitable caspase-3-like protease. Activation of caspase-3-like protease by digitonin-treated lysosomal fractions was specifically suppressed by leupeptin and E-64, inhibitors of cysteine protease. These results indicate that leakage of lysosomal cysteine protease(s) into the cytosolic compartment might be involved in the activation of caspase-3-like protease. 相似文献
42.
The effect of dorsal raphe nucleus (DR) stimulation on the unit discharge of suprachiasmatic nucleus (SCN) neurons was studied and analyzed pharmacologically in the Wistar rats. Experimental results showed that DR stimulation could significantly inhibit the light-induced discharge of SCN neurons. Pharmacologically, this inhibition could be enhanced by monoamine oxidase inhibitor pargyline, attenuated by 5-hydroxytryptamine (5-HT) synthesis inhibitor parachlorophenylalanine and blocked by 5-HT receptor antagonist cyproheptadine. It was suggested that the inhibitory effect of DR stimulation on the light-sensitive SCN neuron discharge might be mediated by 5-HT. 相似文献
43.
High-speed digital signal transmission is a promising new field of communication services. In land mobile radio communication, transmission quality severely suffers from frequency selective fading under multipath radiowave transmission environments. Field test measurement results for 128 kbit/s QPSK signal transmission and delay time spread in the Tokyo metropolitan area are presented. The two-branch diversity reception method was adopted to combat fading. Bit error rate (BER) performance is obtained as a function of delay time spread.<> 相似文献
44.
D. B. McDermott D. S. Furuno N. C. Luhmann Jr. 《Journal of Infrared, Millimeter and Terahertz Waves》1983,4(5):831-845
A dielectric rod is shown to reduce the energy requirements of the electron beam for high-harmonic gyrotron operation. A large interaction filling factor can occur for moderate-energy electrons (~80 keV) spiralling around the rod within the evanescent region of a dielectric waveguide mode. Since the magnetic field strength is reduced by an order of magnitude in an interaction at the tenth harmonic of the cyclotron frequency, a submillimeter-wave gyrotron is now truly feasible because the acceleration voltages can be conveniently produced by DC power supplies. 相似文献
45.
Nansai K Kagawa S Suh S Inaba R Moriguchi Y 《Environmental science & technology》2007,41(4):1465-1472
Today's material welfare has been achieved at the expense of consumption of finite resources and generation of environmental burdens. Over the past few decades the volume of global consumption has grown dramatically, while at the same time technological advances have enabled products with greater efficiencies. These two directions of change, consumption growth and technological advance, are the foci of the present paper. Using quantitative measures for these two factors, we define a new indicator, "eco-velocity of consumption", analogous to velocity in physics. The indicator not only identifies the environmental soundness of consumption growth and technological advance but also indicates whether and to what extent our society is shifting toward sustainable consumption. This study demonstrates the practicability of the indicator through a case study in which we calculate the eco-velocities of Japanese household consumption in 2 years: 1995 and 2000. The rate of technological advance during the periods concerned is quantified in terms of the embodied carbon dioxide emission per yen of product. The results show that the current growth rate of Japanese household consumption is greater than the rate of technological advance to mitigate carbon dioxide emissions. The eco-velocities at the level of individual commodity groups are also examined, and the sources of changes in eco-velocity for each commodity are identified using structural decomposition analysis. 相似文献
46.
Sakai T Hitomi T Sugaya K Kai S Murayama M Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2007,48(5):144-147
Simple and reliable methods using LC/MS have been developed for the determination of the beta-agonist ractopamine in swine and cattle tissues. Ractopamine was extracted with ethyl acetate from muscle and liver, and the ethyl acetate layer was evaporated to dryness. The residue was purified by partition with acetonitrile/n-hexane. In the case of fat, ractopamine was extracted and purified by partition with acetonitrile/n-hexane. The resulting acetonitrile solutions were evaporated to dryness. The residue was dissolved in methanol, and subjected to LC/MS. The LC separation was performed on a Wakosil-II 3C18HG column (150 x 3 mm i.d.) in isocratic mode with 0.05% trifluoroacetic acid-acetonitrile (80:20) as a mobile phase at a flow rate of 0.4 mL/min. The MS detection was performed in the selected ion recording (SIR) mode, with detection of the M + H+ ion of ractopamine (m/z 302) produced by electrospray ionization (ESI). The mean recoveries of the drug from swine muscle (0.01 microg fortified), fat (0.01 microg fortified) and liver (0.04 microg/g fortified) were 99.7%, 99.5% and 100.8%, and those from cattle samples were 108.3%, 97.0% and 109.4%, respectively. The relative standard deviations (RSDs) ranged from 0.1% to 9.5%. The limit of quantification (LOQ) of the drug was 1 ng/g. 相似文献
47.
In this paper, we re-examine the analysis on multinational firms and the theory of international trade and investment in the
set-up with urban unemployment. A great majority of the recipient (host) countries are developing economies that are characterized
by rural–urban migration in the face of urban unemployment. Thus, they have relatively developed urban sectors and less developed
rural sectors. In this context we explore the implications of tariffs and taxes on the urban unemployment rate and national
income. 相似文献
48.
Takuya Katsube Yoko Tsurunaga Mari Sugiyama Toshimichi Furuno Yukikazu Yamasaki 《Food chemistry》2009
The mulberry (Morus alba L.) leaf is a promising dietary source of antioxidants such as quercetin due to its relatively high content of that compound. We investigated effects of an air-drying process on the antioxidant capacity and stability of antioxidant polyphenolic compounds in mulberry leaves. Main compounds playing a central role in antioxidant activities in mulberry leaves are quercetin glycosides and chlorogenic acid. Raw mulberry leaves were air-dried at various temperatures, and antioxidant activity using DPPH radical scavenging assay and levels of antioxidant compounds were measured. DPPH radical scavenging activity and levels of polyphenolic compounds in mulberry leaves air-dried at 60 °C or below were not significantly different from those of freeze-dried mulberry leaves, whereas both values in mulberry leaves air-dried at 70 °C and over decreased significantly. These results indicate that strict temperature control is important in the production of mulberry leaf products to maintain antioxidant activity and levels of polyphenolic compounds. 相似文献
49.
50.
Takayoshi Aoki Kohei Furuno Yoshihiro Tagishi Susumu Ohya Jian-Zhi Ruan 《Atomic Data and Nuclear Data Tables》1979,23(4):349-404
Linear-polarization mixing coefficients for mixed dipole and quadrupole γ radiations have been listed as functions of mixing ratios for integer and half-integer spins up to 26. A familiar type of the Compton polarimeter is briefly discussed in connection with these coefficients. 相似文献