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排序方式: 共有325条查询结果,搜索用时 15 毫秒
51.
Matsuoka-Sakata A Tamura H Asada H Miwa I Taketani T Yamagata Y Sugino N 《Reproduction (Cambridge, England)》2006,131(2):351-360
The present study investigates changes in blood vessel stability and its regulation in the corpus luteum (CL) during pregnancy in the rat. First, blood vessel stability in the CL was evaluated during pregnancy based on vascular leakage, which was quantified by the Evans blue assay. Vascular leakage was highest on day 3, thereafter decreased until day 15 and increased again on day 21. Secondly, to study the regulation of vascular leakage, the expression of angiopoietins was examined in the CL during pregnancy. Angiopoietin-1 (Ang-1) effects maturation and stabilization of newly formed blood vessels, while Ang-2 produces the opposite effect by allowing vascular remodeling. An immunohistochemical study showed both Ang-1 and Ang-2 expression in luteal cells. mRNA and protein levels of Ang-1 were significantly higher on days 12 and 15 than those on days 3 and 21, whereas there was no significant change in Ang-2 expression. Since estradiol contributes to CL development during mid-pregnancy, we finally studied whether estradiol regulates vascular leakage and angiopoietin expression. Rats undergoing hypophysectomy and hysterectomy (hypox-hect) on day 12 were treated with estradiol until day 15. Vascular leakage was increased and Ang-1 expression was decreased by hypox-hect, and these effects were completely reversed by estradiol treatment. In conclusion, blood vessel stability in the CL is likely to be associated with CL development and CL regression, and may be regulated by angiopoietins. Estradiol contributes to blood vessel stabilization in the CL during mid-pregnancy, which is associated with an increase in Ang-1 expression. 相似文献
52.
Zakaria MB Suzuki N Shimasaki K Miyamoto N Huang YT Yamauchi Y 《Journal of nanoscience and nanotechnology》2012,12(6):4502-4507
In this research paper, we synthesize various types of mesoporous titania nanoparticles (MTNs) with suitable surface area and pore size while creating anatase frameworks by applying hydrothermal treatment or calcination at different temperatures. Wide-angle XRD patterns and N2 adsorption-desorption isotherms reveal that the MTNs with crystallized anatase frameworks can be synthesized after an optimized hydrothermal treatment. In contrast, calcination of MTNs at high temperature caused the collapse of mesoporous structure, resulted in drastic reduction of the surface area of the MTNs. In addition, we investigate the photocatalytic activity of the prepared MTNs by measuring the degradation of methylene blue (MB). The results show that the reaction rates of the photocatalytic MB decomposition strongly depend on the degree of crystallinity in the MTNs frameworks and on the surface area of MTNs. 相似文献
53.
Hamid Oveisi Norihiro Suzuki Pavuluri Srinivasu Yusuke Yamauchi 《Thin solid films》2010,518(23):6714-11933
Here we demonstrate facile synthesis method for formation of highly ordered mesoporous cubic Im-3 m titania thin film. The mesostructural ordering is strongly dependent on the aging condition after the spin-coating. The aging condition under low temperature and low humidity is found as an optimum condition for achieving highly ordered mesostructure in titania thin films. The effects of other important synthetic parameters, such as pH of the precursor solutions and aging periods, on the mesostructural ordering are carefully examined. After the calcination, continuous mesoporous films with partially crystallized frameworks are formed without any cracks. The mesostructure of the calcined films is formed by thermal shrinkage of the original Im-3 m mesostructure. The mesostructural change in the films calcined at various temperatures are studied by using the grazing-incidence small-angle X-ray scattering (GI-SAXS). The GI-SAXS patterns show the strong shrinkage along the perpendicular direction to the substrate by increasing the calcination temperature. 相似文献
54.
Yuji KOHGO Akira TAKAHASHI Tomokazu SUZUKI 《Frontiers of Structural and Civil Engineering》2010,4(1):92
In this paper we analyzed a real fill-type dam, named the Minami-Aiki Dam, to verify a numerical consolidation method with an elastoplastic model for unsaturated soils. The validities were conducted by comparing the analyzed and measured values during construction and impounding. The settlements calculated showed good agreement to those observed. Though the changing patterns of the measured and calculated pore water pressures were similar, the amounts of pore water pressures induced by the self-weights of embankment and the dissipation speeds were different. The earth pressures measured at the bottom of the core zone showed good agreement with those calculated. This method is valid for estimating behavior of fill-type dams during construction and impounding. 相似文献
55.
56.
Naohiro Terasawa Norihiro Ono Ken Mukai Tomoyuki Koga Nobuyuki Higashi Kinji Asaka 《Carbon》2012,50(1):311-320
Actuators were developed using activated and non-activated multi-walled carbon nanotube (MWCNT)–ionic liquid (IL) gel electrodes and compared to a single-walled carbon nanotube (SWCNT)-based actuator with respect to the electrochemical and electromechanical properties. The activated MWCNT–COOH/polymer actuator surpassed the SWCNT/polymer actuator in terms of the generated strain. 相似文献
57.
KAZUMARU IIJIMA KOJI SUZUKI KAZUTAKA OZAKI HIDETOSHI KURIYAMA YASUSHI KITAGAWA HIROSHI YAMASHITA 《Journal of food quality》2006,29(5):531-542
To identify food‐associated foreign substances, a DNA analysis consisting of 18S rDNA sequencing and homology search analysis has been developed. In this method, we designed universal primer pairs for specific amplification of animal and plant 18S rDNA and constructed an original DNA database storing partial 18S rDNA sequences of 222 organisms commonly used for culinary purposes. In the model experiments, food materials were successfully identified, indicating that our DNA analysis method can be practically applied to the identification of food‐associated foreign substances. It is also expected that this method complements conventional morphological and compositional analysis, leading to more accurate and reliable identification of food‐associated foreign substances. 相似文献
58.
NORLITA G. SANCEDA TADAO KURATA YOSHIKATSU SUZUKI NOBUHIKO ARAKAWA 《Journal of food science》1992,57(5):1120-1135
Volatile acids of aerobically and anaerobically fermented fish sauces were investigated using GC and GC-MS. There was no significant difference in pH values of the two types of sauces. Volatile acids found in the aerobically fermented sauce had concentrations significantly higher than the anaerobically fermented one. Sensory evaluation revealed that the aroma of the anaerobically fermented sauce was a little sweet, less acidic and less rancid than the aerobically made sauce which was sharp, and cheesy. Thus, fermentation under anaerobic condition altered the aroma quality of the sauce during manufacturing, yielding an acceptable product. 相似文献
59.
MOHAMAD RAZEGHI NOBUYUKI SATO TAKEHISA SUZUKI KUNIYOSHI YOKOO SHOICHI ONO 《International Journal of Electronics》2013,100(5):533-542
This paper proposes a modified peniotron which is expected to increase both handling power and conversion efficiency compared with the original peniotron, and reports the analytical results or its operational characteristics using some computer simulations. Analytical results assuming the fundamental operation of ω0 ? ωc at l0GHz show that an extremely high transverse efficiency of nearly 100% may be attainable over a considerably wide range of output power. The tube uses a TE11 rectangular waveguide cavity instead of the double-pair ridged waveguide cavity used for the original peniotron. 相似文献
60.
ON THE PARAMETER-SPACE CLASSIFICATION OF THE DYNAMIC BEHAVIOR OF A CONTINUOUS MICROBIAL FLOW REACTOR
SHIGEHARU SUZUKI KAZUYUKI SHIMIZU MASAKAZU MATSUBARA 《Chemical Engineering Communications》2013,200(5-6):325-335
Recently Agrawal et al.1 classified the dynamic behavior of continuous stirred tank fermentor for the Monod's model and the two parameter hump function model with variable yield coefficient in the parameter space. We employed the more general three parameter substrate inhibition model which includes the Monod's model as a limiting case, derived the boundary equations which rigorously divide the parameter space of different dynamic behavior, and showed the interesting phenomenon that a limit cycle suddenly vanished for the slight change in the Damköhler number by computer simulation. 相似文献