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991.
Zhou H Ohno N Terada N Saitoh S Naito I Ohno S 《Reproduction (Cambridge, England)》2008,136(5):599-610
Despite the potential association of polycystic ovary (PCO) syndrome with hemodynamic changes, follicular microenvironment and the involvement of blood follicle barriers (BFB), a histopathological examination has been hampered by artifacts caused by conventional preparation methods. In this study, mouse ovaries of a mifepristone-induced PCO model were morphologically and immunohistochemically examined by in vivo cryotechnique (IVCT), which prevents those technical artifacts. Ovarian specimens of PCO model mice were prepared by IVCT or the conventional perfusion fixation after s.c. injection of mifepristone. Their histology and immunolocalization of plasma proteins, including albumin (molecular mass, 69 kDa), immunoglobulin G (IgG, 150 kDa), inter-alpha-trypsin inhibitor (ITI, 220 kDa), fibrinogen (340 kDa), and IgM (900 kDa), were examined. In the PCO model, enlarged blood vessels with abundant blood flow were observed in addition to cystic follicles with degenerative membrana granulosa. The immunolocalization of albumin and IgM in the PCO model were similar to those in normal mice. Albumin immunolocalized in the blood vessels, interstitium or follicles, and IgM was mostly restricted within the blood vessels. In contrast, immunolocalization of IgG, ITI, and fibrinogen changed in the PCO model. Both IgG and ITI were clearly blocked by follicular basement membranes, and hardly observed in the membrana granulosa, though fibrinogen was mostly observed within blood vessels. These findings suggest that increased blood flow and enhanced selectivity of molecular permeation through the BFB are prominent features in the PCO ovaries, and changes in hemodynamic conditions and permselectivity of BFB are involved in the pathogenesis and pathophysiology of PCO syndrome. 相似文献
992.
Seki S Kouya T Tsuchiya R Valdez DM Jin B Hara T Saida N Kasai M Edashige K 《Reproduction (Cambridge, England)》2008,135(3):285-292
In zebrafish oocytes, it has been reported that a 60 or 75% Leibovitz L-15 medium or simple balanced saline solution containing 17alpha, 20beta-dihydroxy-4-pregnen-3-one (DHP) is effective for nuclear maturation. However, most of the oocytes that matured under these conditions were not fertilized and did not hatch. Thus, these in vitro maturation methods could not support the cytoplasmic maturation of zebrafish oocytes. Therefore, we tried to develop a reliable in vitro maturation method for zebrafish oocytes, which supports their ability to be fertilized and to develop till hatching. When zebrafish oocytes at stage III were cultured in 50-100% Leibovitz L-15 medium supplemented with DHP, the highest rates of cleavage (24%) and hatching (12%) were obtained from oocytes matured in 90% Leibovitz L-15 medium. When we examined the suitable pH (7.5-9.5) of the 90% medium, higher rates of cleavage (45%) and hatching (33%) were obtained in oocytes matured at pH 9.0 than at pH 7.5, 8.5, or 9.5 (cleavage rate, 16-29%; hatching rate, 8-21%). In oocytes matured in 90% Leibovitz L-15 medium at pH 9.0, high rates of cleavage (70%) and hatching (63%) were obtained when oocytes were cultured for 270 min with 0.5 mg/ml BSA. Thus, 90% Leibovitz L-15 medium at pH 9.0 containing 0.5 mg/ml BSA was effective for normal maturation of zebrafish oocytes. This method will become a powerful tool for understanding the mechanism of in vitro maturation in zebrafish oocytes and for the practical use of immature oocytes. 相似文献
993.
Local buckling behaviors of box section with various stiffeners subjected to compressive load. An analytical procedure for the elastic local buckling problems of box‐section with open, closed and L‐type stiffeners by the extended matrix method is presented. An exact solution can be obtained by treating the compressive box‐section with stiffeners as the branching panels in the transfer matrix method. The results are given as two local buckling behaviors. The first local buckling behavior is the local buckling shape to become a joint at the position of the each stiffener, and the second local buckling behavior is the local buckling shape of individual plate to compose box‐section. 相似文献
994.
Pham HT Kitsuneduka M Hara J Suto K Inoue C 《Environmental science & technology》2008,42(19):7470-7475
The transformation of trichloroethylene (TCE) in natural mineral iron disulfide (pyrite) aqueous suspension under different oxygen conditions was investigated in laboratory batch experiments. TCE transformation was pursued by monitoring its disappearance and products released with time. The effect of oxygen was studied by varying the initial dissolved oxygen concentration (DO(i)) inside each reactor. Transformation rates depended strongly on DO(i) in the system. In anaerobic pyrite suspension, TCE did not transform as it did under aerobic conditions. The transformation rate increased with an increase in DO(i). The TCE transformation kinetics was fitted to a pseudo-first-order reaction with a rate constant k (h(-1)) varying from 0.004 to 0.013 for closed systems with DO(i) varying from 0.017 to 0.268 mmol/L under the experimental conditions. In the aerobic systems, TCE transformed to several organic acids including dichloroacetic acid, glyoxylic acid, oxalic acid, formic acid, and finally to CO2 and chloride ion. Dichloroacetic acid was the only chlorinated intermediate found. Both TCE and the pyrite surface were oxidized in the presence of O2. Oxygen consumption profiles showed O2 was the common oxidant in both TCE and pyrite oxidation reactions. Ferric ion cannot be used as an alternative oxidant to oxygen for TCE transformation. 相似文献
995.
S. Gandhi R. Hari Hara Subramani T. Ramakrishnan A. Sivabalan V. Dhanalakshmi M. R. Gopinathan Nair R. Anbarasan 《Journal of Materials Science》2010,45(6):1688-1694
The ultrasound (US) assisted one pot method has used to synthesize CuO nanoparticles. The fourier transform infrared spectroscopy
(FTIR) spectrum shows a characteristic peak of metal–oxygen bond at 535 cm−1, which confirms the CuO formation. The high resolution transmission electron microscope (HRTEM) images of the synthesized
nano-CuO confirms the size of nanorods with the length of approximately 25–30 nm, and its breadth is less than one nanometer.
X-ray diffraction (XRD) pattern of CuO can be readily assigned to those of crystalline CuO, indicating the formation of single-phase
CuO with monoclinic structure. The synthesized nano-CuO is mixed with poly(vinyl alcohol) (PVA) to prepare the PVA/CuO nanocomposite
to improve the thermal stability of PVA. Their physico-chemical properties are examined by means of FTIR, XRD, differential
scanning calorimetry, thermogravimetric analysis, HRTEM, and scanning electron microscope (SEM) techniques. 相似文献
996.
Hiroki Nagai Sohei Aoyama Hiroki Hara Chihiro Mochizuki Ichiro Takano Tohru Honda Mitsunobu Sato 《Journal of Materials Science》2010,45(20):5704-5710
This article describes the post-annealing treatment of a rutile thin film, which was fabricated on a quartz glass substrate
by heat treating a precursor film in air for 15–60 min by using a process involving a Ti complex of EDTA. The transparent,
crack-free rutile thin films thus obtained were characterized by means of X-ray diffraction, X-ray photoelectron spectroscopy,
and field emission scanning electron microscopy. The photoluminescence emission band of the post-annealed rutile thin films
appeared at ca. 800 nm, which is in the extraordinary low-energy region, although no emission band in the region could be
observed for the rutile thin film before annealing. It was revealed that the extraordinary emission band of the thin films
at 800 nm is strongly related both to the orientation of the constituent crystals along the (110) plane and to the incorporation
of O atoms into the O-defect sites that were in the rutile thin film before the post-annealing treatment. 相似文献
997.
Tohru Hayakawa Chihiro Mochizuki Hiroki Hara Fei Yang Hong Shen Shenguo Wang Mitsunobu Sato 《Journal of materials science. Materials in medicine》2010,21(1):251-258
The cortical bone response towards poly(lactide-co-glycolide) (70/30) (PLGA) (70/30)/apatite complex scaffolds with different
levels of crystallinity was investigated. Apatite with different levels of crystallinity, Ca-deficient hydroxyapatite (CDHA),
which has a low crystallinity, and a mixture of carbonated hydroxyapatite (CHA) and CDHA, which has a higher crystallinity,
were prepared from an aqueous mixture of Ca-EDTA complex, H2O2, H3PO4, and NH4OH. Two porous PLGA(70/30)/apatite composite scaffolds, composite scaffold A (containing low crystallinity CDHA) and composite scaffold B (containing the higher crystallinity CHA/CDHA mixture), were prepared. Afterwards, pure porous PLGA and the two composite
scaffolds were implanted into the cortical bone of rabbit tibiae for 12 weeks. High-resolution microfocus X-ray computed tomography
and histological examinations revealed a better bone response for composite scaffold A compared with PLGA and composite scaffold B. For composite scaffold A, the original bone defect was almost filled with new bone. Quantitative analysis revealed that composite scaffold A produced a significantly greater amount of new bone. The present study demonstrated that the level of apatite crystallinity
influences bone response. A PLGA/apatite porous composite with a low level of apatite crystallinity shows promise as a bone
substitute or scaffold material for bone tissue engineering. 相似文献
998.
Eiichi Hara Tomohiro Yokozeki Hiroshi Hatta Yutaka Iwahori Takashi Ishikawa 《Composites Part A》2010,41(10):1538-1544
The purpose of the present study was to establish a measuring procedure for the out-of-plane tensile modulus of CFRP laminates using a direct tensile loading method. Experimental results of out-of-plane tensile tests were compared with numerical predictions. Experimental results showed that the apparent strain of unidirectional (UD-) and quasi-isotropic (QI-) CFRP laminates varies with specimen geometry, gage length, and measuring positions in spite of the uniform tensile strain being loaded to the specimen. This tendency was confirmed to be precisely simulated by finite element analyses. Thus, these results should be taken into consideration in evaluating out-of-plane tensile modulus. The mechanisms underlying these strain variations are discussed, and based on the discussion, guidelines are given for using strain gage output in the determination of out-of-plane tensile modulus of the CFRP laminates. 相似文献
999.
A “Multi-Layered Parallel Production Management” concept and its support tools-system for decentralized production management are proposed, on the basis of a “Sector optimization” concept and a “Tools-system” concept. The necessity for introducing a production system decentralization with a long range/total systematic view, for realizing a flexible and effective production management, is first discussed. Then, discussion is centered on production management quality enhancement and its support methodology. Further, a tools-system for “Multi-Layered Parallel Production Management” support is proposed and its applications are discussed. 相似文献
1000.
Hara H. Sakurai T. Noda M. Nagamatsu T. Seta K. Momose H. Niitsu Y. Miyakawa H. Watanabe Y. 《Solid-State Circuits, IEEE Journal of》1991,26(11):1615-1620
A channelless gate array has been realized using 0.5-μm BiCMOS technology integrating more than two million transistors on a 14-mm×14.4-mm chip. A small-size PMOS transistor and a small-size inverter are added to the conventional BiNMOS gate to form the BiPNMOS gate. The gate is suitable for 3.3-V supply and achieves 230-ps gate delay for a two-input NAND with full-swing output. Added small-size MOS transistors in the BiPNMOS basic cell can also be used for memory macros effectively. A test chip with four memory macros-a high-speed RAM, a high-density RAM, a ROM, and a CAM macro-was fabricated. The high-speed memory macros utilize bipolar transistors in bipolar middle buffers and in sense amplifiers. The high-speed RAM macro achieves an access time of 2.7 ns at 16-kb capacity. The high-density RAM macro is rather slow but the memory cell occupies only a half of the BiPNMOS basic cell using a single-port memory cell 相似文献