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71.
Sato T Kanai Y Noma T Kanai-Azuma M Taya S Matsui T Ishii M Kawakami H Kurohmaru M Kaibuchi K Wood SA Hayashi Y 《Reproduction (Cambridge, England)》2004,128(5):583-594
Usp9x, an X-linked deubiquitylating enzyme, is stage dependently expressed in the supporting cells (i.e. Sertoli cells and granulosa cells) and germ cells during mouse gametogenesis. Af-6, a cell junction protein, has been identified as a substrate of Usp9x, suggesting a possible association between Usp9x and Af-6 in spermatogenesis and oogenesis. In this study, we examined the expression pattern of Af-6 and Usp9x and their intracellular localization in testes and ovaries of mice treated with or without pregnant mare serum gonadotropin (PMSG), an FSH-like hormone. In both testes and ovaries, Af-6 expression was predominantly observed in supporting cells, as well as in steroidogenic cells, but not in any germ cells. In Sertoli cells, Af-6 was continuously expressed throughout postnatal and adult stages, where both Af-6 and Usp9x were enriched at the sites of Sertoli-Sertoli and Sertoli-spermatid junctions especially at stages XI-VI. In the granulosa cells, Af-6, as well as Usp9x, was highly expressed in primordial and primary follicles, but its expression rapidly decreased after the late-secondary follicle stage. Interestingly, in PMSG-treated mice, the expression levels of Af-6 and Usp9x were synchronously enhanced, slightly in Sertoli cells and strongly in granulosa cells of the late-secondary and Graafian follicles. Such closely correlated expression patterns between Af-6 and Usp9x clearly suggest that Af-6 may be deubiquitylated by Usp9x in both Sertoli and granulosa cells. It further suggests that the post-translational regulation of Af-6 by Usp9x may be one potential pathway to control the cell adhesion dynamics in mammalian gametogenesis. 相似文献
72.
Lan Hong Keiji Okumura Masamichi Sano 《Metallurgical and Materials Transactions B》1999,30(6):1003-1008
An investigation of the reduction of magnesia by aluminum was carried out using a nonisothermal gravimetric technique under
an argon atmosphere, in the temperature range from 1273 to 1873 K. The mixture of magnesia and aluminum powders was formed
into a pellet under various isostatic pressures. It was found that magnesia is reduced by aluminum to form magnesium and spinel
at first, and then the excess aluminum reacts with spinel slowly. The temperature at which the reaction starts increases with
an increasing heating rate. The reaction rate is also affected by pellet-forming conditions. A kinetic model is proposed to
explain the experimental results. The activation energy of the reduction of magnesia by aluminum is 151.2 kJ/mol. Good agreement
between calculated and experimental results is obtained. 相似文献
73.
Shintaro Sugai Masamichi Ikeguchi & Akio Shimizu 《International Journal of Food Science & Technology》1999,34(5-6):437-443
Summary Properties of three equine milk proteins, lysozyme, α-lactalbumin, and β-lactoglobulin, were investigated and compared with the corresponding ones of bovine milk. The subsite structure similar to that in hen egg lysozyme was assumed in the functional region of lysozyme from interaction with inhibitors. α-lactalbumin has structures similar to those of bovine, but less stability of its intact and 3SS forms are observed than the corresponding bovine irrespective of [Ca2+ ] because of the entropy factors. Although the folding of β-lactoglobulin at acid pH is very similar to that of the bovine protein the conformation of the I strand is different from that of bovine I strand at neutral pH according to NMR data. 相似文献
74.
75.
Satoshi Murakawa Yuichiro Wada Yuta Tamura Masamichi Saitoh Yuki Aoki Ryuji Nomura Yuichi Okuda 《Journal of Low Temperature Physics》2008,150(3-4):154-159
We measured the complex transverse acoustic impedance of superfluid 3He in the B phase by coating a surface with 4He to study the boundary condition dependence of the surface bound states. Observed features in the temperature dependence
were similar to those without 4He coating. However, temperatures showing singularities became higher and variations in the dependence became smaller. The
small variations indicated that a specular surface was realized by the 4He coating. Increase in the singularity temperature indicated that the bandwidth of the surface Andreev bound states became
broader by the coating.
相似文献
76.
The effect of the binding sites of the terminal groups -S on gold on currents through a single molecular junction (MJ) of Au/1,6-hexanedithiol/Au was studied by measuring current-separation (i-s) curves during repeated formation of a break junction in UHV-STM. Three different single molecular conductance (SMC) values (i.e. G(m)(HC), G(m)(MC) and G(m)(LC)) were found by a careful analysis of corrected current histograms for background tunneling currents using a previously developed robust statistical analysis. Here, HC, MC and LC represent a single MJ with high, medium and low conductance, respectively. These three SMC values are attributed to three different contact modes (i.e. strong-strong, strong-weak (or weak-strong) and weak-weak bindings at the two ends). In addition to these three SMC values due to the different contacts, another lower SMC value was newly observed in the corrected histogram. The presence of the fourth SMC is specific to MJs of alkanedithiols and is attributable to LC of a single alkylene chain with gauche rich conformation, which has a lower SMC value than that of LC with all-trans conformation as proposed previously (Fujihira M et al 2006 Phys. Chem. Chem. Phys. 8 3876). Due to the effects of the contact and the conformational change, it was difficult to determine six different SMC values corresponding to two different conformations (i.e. gauche-rich versus all-trans) with three different contacts (i.e. HC, MC and LC). In addition to this complexity, the current steps corresponding to HC, MC and LC almost always appeared in this order in measured i-s curves during separation. The current step observed here could not only be a contribution from a single molecule, but also contributions from a few groups of molecules that happen to link gold atoms of the substrate with those of the tip apex. Therefore, the SMC value for HC obtained as a peak or a set of peaks in the current histogram could be based upon the sum of the current of HC and those of MCs and LCs coexisting in parallel, unless every MJ would change successively from HC to MC and MC to LC. Namely, the currents through coexisting MCs and LCs would raise the intrinsic current observed for HC itself, while those through coexisting LCs would raise the intrinsic current for MC. To avoid such errors in determining the true SMC, we demonstrate here a new method based upon analyses of individual i-s curves referred to as jump height analyses of individual i-s curves. By this method, the true SMC of LC(all-trans) was determined to be 1.6?nS (i.e. G(m) (LC, all-trans) of 2.1 × 10(-5)G(o)) without ambiguity in spite of the possible presence of LCs(gauche rich) in parallel. 相似文献
77.
Tanaka S Nogawa M Yamakoshi T Yamakoshi K 《IEEE transactions on bio-medical engineering》2007,54(10):1892-1895
For the noninvasive and accurate measurement of instantaneous blood pressure (BP) in the radial artery, the performance of a device based on the principle of volume-compensation was assessed by comparison with simultaneous measurement of direct (invasive) radial artery pressure in nine healthy subjects. Bias and precision of systolic BP (SBP) and diastolic BP (DBP) derived from Bland-Altman plots of data from the present system and the direct method averaged -0.5 +/- 2.1 mmHg and 0.6 +/- 1.8 mmHg respectively, over a wide range of SBP and DBP. These results clearly indicate that, using this system, instantaneous radial artery pressure can be measured noninvasively with high accuracy. 相似文献
78.
Solid-state dye-sensitized solar cells (DSSCs) were fabricated in which the thin p-CuI film acts as a hole collector. Influences of the different preparation methods, composition, aging time of the TiO2 pastes and sensitizing time on the performance of the cells were investigated. Different preparation routes for the TiO2 paste do not obviously affect the performance of the cells. The volume of water, acetic acid and 2-propanol contained in the TiO2 pastes and the amount of the TiO2 powder were determined. The efficiency of the cells remains nearly stable when the aging period of the TiO2 pastes is within one week. The favorable dying time is above 2 h. The cells having a favorable performance deliver a mean short-circuit photocurrent of 10.8 mA cm−2 and mean open-circuit voltage of 0.61 V at 100 mW cm−2 (1.5 AM). The mean fill factor and the mean efficiency of these cells are 0.55% and 3.7%, respectively. The short-circuit photocurrent rapidly decays after 3 h, and at the same time, the open-circuit voltage slowly decreases when the time increases, and then remains nearly stable after 24 h. 相似文献
79.
Masamichi Kawano 《资源与产业》2012,14(6):70-76
为了得到一个国家不同地区人口分布的最佳模式,对中央政府给每个地区的拨款进行了研究。如果所有地区大小相同,可适用亨利·乔治定理,即要使每个地区都获得人口规模最优,所有土地的租金都应当用于公共物品投资。但是如果各地区的面积不相等,则不适用亨利·乔治定理。这种情况下,要提高所有地区居民的福利,中央政府应该重新分配税收收入,以实现帕累托改进。最后,阐述了税收最佳分配方案以及帕累托改进方法。 相似文献
80.
The electric railway system is the highest class of energy efficient transportation means. This is due to two important points: (i) low running resistance (including low energy losses) and (ii) energy regeneration in braking. Regenerative braking of railway electric vehicles is effective when the other powering ones, in other words electrical load, exist near the regenerating train on the same electrified line. So, early in the morning and at midnight, or in the low‐density district lines, regeneration cancellation phenomenon often occurs and the regenerative brake force cannot be operated in accordance with the recommended value. Newly appeared high‐performance energy storage devices press the issues of energy storage and reuse technologies on ground and on vehicles. Hybrid energy source is one effective solution. In this paper, as an example, we show our trolley and on‐board battery hybrid controlled tramcar, developed to reduce regeneration cancellation. With the trolley line collective power as well as charge and discharge power of the on‐board lithium ion rechargeable battery, the hybrid energy providing and regenerating technology is achieved. The running test results show a maximum regenerative ratio of 44%, which is top class value in an electric railway system. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献