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941.
K Takenaka M Ito M Kumagai H Yamakawa Y Sugimoto H Yamakawa Y Nishimura N Sakai 《Canadian Metallurgical Quarterly》1998,38(9):566-568
A 61-year-old female presented with a unique case of moyamoya disease associated with pulmonary sarcoidosis. She was admitted for sudden onset of left temporalgia with episode of numbness on face, tongue, and upper extremity on the right side. The next morning, she had symptoms of Gerstmann syndrome and her ability to speak was disturbed. Her medical history included radical resection of lung cancer on the right side. She had no symptoms of pulmonary sarcoidosis. Neuroimaging showed an infarction in the left occipital lobe. Angiography showed occlusions of the bilateral internal carotid arteries at the supraclinoid portions. Subsequently, a left superficial temporal artery-middle cerebral artery anastomosis with encephalo-myo-synangiosis was performed. Ninety-three days after admission, she suddenly developed dyspnea which resulted in death 3 hours later. Autopsy findings showed typical epithelioid granulomas of sarcoid type in the lymph nodes of the peribronchus, lung, and liver. Thrombotic emboli were found in the bilateral pulmonary arteries, and marked fibrous intimal thickening in the bilateral internal carotid arteries. Immunological reaction with inflammatory events may cause pathological changes in patients with moyamoya disease or sarcoidosis. The co-incidence in this case suggests that some common inflammatory events may be involved in the pathogenesis of these diseases. 相似文献
942.
The motion of a single nitrogen gas bubble chain and the structure of water flow field surrounding the chain were experimentally studied. We developed a bubble generator that can control both the bubble diameter and the generation frequency independently. Experimental conditions of bubble Reynolds number and bubble distance divided by bubble diameter were from 300 to 650 and from 6.5 to 300, respectively. We discuss the interaction effects on the motion of each bubble rising in a chain, as compared to the effects of a single rising bubble. The bubble trajectories and the surrounding water flow fields in the state of bubbles rising in a chain were investigated using a high-speed digital video camera and an analog single-lens-reflex camera. We observed two important physical phenomena. First, bubbles passed through a nearly identical path in the case of low frequency of bubble production. On the contrary, at a height of approximately 50 mm from the nozzle, the bubbles in the case of high frequency deviated and scattered from this path due to bubble-bubble interaction. Second, with higher bubble production frequency, coherent bubble chain and the characteristic structure of the surrounding water flow called “liquid jet” were observed near the nozzle. The direction of liquid jet flow differed from the bubble trajectory. We theoretically investigated the relation of coherent bubble chain and liquid jet by applying the conservation of liquid momentum. 相似文献
943.
Kitagawa Y. Ozaki N. Takata Y. Ikeda N. Watanabe Y. Sugimoto Y. Asakawa K. 《Lightwave Technology, Journal of》2009,27(10):1241-1247
A photonic crystal (PC)-based symmetric Mach-Zehnder type all-optical switch (PC-SMZ), previously operated by single pump pulse alone, has been operated newly by a multiple-pump pulse train corresponding to a repetition frequency of 40 GHz at pulse energy as low as 10 fJ. The device involves quantum dots (QDs) in two parallel PC arms as optical nonlinear media and functions as a time-differential phase modulator caused by the pump pulse inducing carriers in the QD. Prior to the switch operation, sequential time response of the phase shift for a probe pulse was investigated in detail by changing the power and repetition rate of the pump pulse in the straight PC waveguide configuration. Besides, PC and QD parameters were explored for possibility of 100% on-off switching ratio. As a result, five QD layers, 40-ps QD relaxation-time, 500-mum PC-length and use of as low as 0.05 c PC group-velocity (c; light velocity in vacuum) were found to implement the 100% switching ratio. Since each of these parameters has ever been achieved experimentally, the result will pave a promising way to an ultra-small and ultra-fast integrated all-optical switch. 相似文献
944.
K Sato N Sugimoto M Ohta T Yamazaki T Maitani K Tanamoto 《Food Additives & Contaminants》2003,20(11):1015-1022
Carthamin is a well-known major pigment in carthamus red colourant. When analysed by HPLC on an ODS column, the colorant separated into two distinct reddish pigments, with both components having almost identical photodiode array spectra. LC/MS analysis suggested one of the compounds was carthamin, whilst the other was an unknown minor pigment. The minor pigment was purified and isolated from the colorant by preparative LC/MS collecting the faction based on monitoring the deprotonated molecule [M-H](-) m/z 953 in electrospray negative-ion mode. The structure was elucidated as a hydroxyethyl ether of carthamin, a novel compound, by means of NMR and HR-FAB-MS analyses. 相似文献
945.
S Tsukuda E Sugimoto T Watabe M Amanuma A Heshiki 《Canadian Metallurgical Quarterly》1998,16(4):301-303
Acute promyelocytic leukemia (APL) originate from chromosomal translocations generating two types of fusion proteins both involving the retinoic acid receptor alpha (RAR alpha) and either the gene PML (t(15;17)) or PLZF (t(11;17)). Recent publications cast a new light on the detailed molecular mechanism underlying the oncogenic activity of these fusion proteins which block myeloid terminal differentiation by recruiting histone deacetylases to the promoters of target genes through co-repressor proteins. They also explain the different responses to treatment by all-trans retinoic acid (ATRA) of these two variants which are otherwise clinically indistinguishable. 相似文献
946.
K Sugimoto S Nakagawa K Mikami T Nomoto S Urano T Nakamura H Nakanishi H Watanabe J Inazawa T Abe 《Canadian Metallurgical Quarterly》1997,43(11):785-789
A 65-year-old man, on whom transurethral resection had been performed twice for bladder cancer in the past, was admitted to our hospital for further Class V urinary cytology examination. A low density area of 1.5 cm in diameter in the left renal pelvis without enhancement was the only abnormal sign on computed tomographic (CT) imaging. Malignant cells were not detected by random biopsy of the urinary bladder. The retrograde pyelogram showed no filling defect on the left renal pelvis or ureter. The cytological diagnosis of the right split renal urine was Class III, and that of the left split renal urine was Class V. Fluorescence in situ hybridization (FISH) analysis, using specific probes for chromosome 8q21.3 and the centromere chromosome 11, was performed on cells from the bilateral split renal urine. Cells collected from the right split renal urine showed a normal disomic pattern, while those from the left split renal urine included an aneusomic pattern with polysomy. Left total nephroureterectomy was carried out. Histopathology proved invasive renal pelvic cancer. Thus FISH analysis may be useful for the localization of renal pelvic or ureteral cancers, which are difficult to diagnose. 相似文献
947.
Koichi Sugimoto 《野外机器人技术杂志》2003,20(8):501-508
By determining a basis of s linear space of twists of a loop in amechanism by passive joint axes in the loop, the concise expressions among active joint torques and wrenches acting on links of a mechanism can be obtained. For the reason that the expressions are based on the basis vectors of joint axes of a mechanism, the algorithm is independent on types of mechanisms such as planar, spherical, spatial, etc. Also, the constraint conditions in loops can be dealt with separately for each loop. It makes the algorithm simple and can reduce the computational cost. By modifying the algorithm, simple expressions for parallel mechanisms can also be obtained. © 2003 Wiley Periodicals, Inc. 相似文献
948.
A Suda Y Takiguchi S Omori K Akadegawa H Miyazawa T Sugimoto K Hiroshima H Kimura K Nagao T Kuriyama 《Canadian Metallurgical Quarterly》1997,35(9):965-968
A 68-year-old male complaining of hemosputum was admitted to our hospital. Fiberoptic bronchoscopic examinations revealed bronchial polyps and a flat foreign body-like substance in the left main bronchus. A closer inspection of a biopsied bronchial inflammatory polyp showed inflammatory edema with hypervascularization in the submucosal space and inflammatory cell infiltration. Following complete removal of this foreign body-like substance, the polyps disappeared within six weeks. It is therefore feasible to assume that the polyps appeared as a reaction to this extrinsic substance. The origin of the foreign matter is not obvious because the patient had no history of aspiration and because the histological examination did not confirm that it was a foreign body. The substance could have been formed out of the organization and calcification of some secretes in the bronchus. 相似文献
949.
Thermostability of sperm genome against freezing-thawing and high temperature treatments was assessed by comparing the degradation patterns of genomic DNAs from epididymal sperms and somatic tissues. Golden hamster liver, kidney, epididymal sperm, and testis were frozen and thawed repeatedly, or incubated in a hot water bath. Genomic DNAs were isolated and then separated by agarose gel electrophoresis. It was revealed that the size of sperm genomic DNA was hardly changed after freezing-thawing treatment, however, the DNA sizes of the other three tissues were gradually reduced with an increasing number of freezing-thawing cycles. In contrast, high temperature treatment appears to damage not only the genomic DNAs of somatic cells but also those of spermatozoa. 相似文献
950.
In‐situ formation of metal nanoparticle/acrylic polymer hybrid and its application to miniemulsion polymerization 下载免费PDF全文
We present in‐situ formation of metal nanoparticle/acrylic polymer hybrid and its application to prepare hybrid latex particles by miniemulsion polymerization. On the surface of a silver nanoparticle/silica nanoparticle/acrylic polymer hybrid layer formed in‐situ on a polyethylene terephthalate (PET) substrate, a copper film is deposited using electroless copper deposition. Silver nanoparticles, which are formed in‐situ via the reduction of silver ion by radical species and subsequent annealing, work as a catalyst for the electroless deposition. Miniemulsion polymerization via the in‐situ formation of nanoparticles affords nanoparticle/acrylic polymer hybrid latex particles and polymer particles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42675. 相似文献