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81.
Y Ono H Manki K Yoshimura T Muramatsu H Mizushima S Higuchi G Yagi S Kanba M Asai 《Canadian Metallurgical Quarterly》1997,74(5):501-503
Only five cases of paraganglioma of the prostate have been reported hitherto. The tumours may be functional (phaeochromocytomas) or non-functional and benign or malignant. We present a sixth case--a non-functional, benign paraganglioma of the prostate--with a review of the literature. 相似文献
82.
M Ohshima H Miyoshi K Sakamoto K Takegami J Iwata K Kuwabara H Iwamura T Yagi 《Canadian Metallurgical Quarterly》1998,37(18):6436-6445
A wide variety of alkyl derivatives of Q2 (6-geranyl-2, 3-dimethoxy-5-methyl-1,4-benzoquinone) and DB (6-n-decyl-2, 3-dimethoxy-5-methyl-1,4-benzoquinone), in which methoxy groups of the 2- and/or 3-positions of the quinone ring were replaced by other bulky alkoxy groups from ethoxy to butoxy, were prepared by novel synthetic procedures. Electron-accepting activities of the bulky quinones were investigated with bovine heart mitochondrial complex I and its counterpart of Paracoccus denitrificans(NDH-1) to elucidate structural and functional features of the quinone reduction site of the enzymes. The bulky quinone analogues served as sufficient electron acceptors from the physiological quinone reduction site of bovine complex I. Considering the very poor activities of even the ethoxy derivatives as substrates for other respiratory enzymes such as mitochondrial complexes II and III [He, D. Y., Gu, L. Q., Yu, L., and Yu, C. A. (1994) Biochemistry 33, 880-884], this result indicated that the quinone reduction site of bovine complex I is spacious enough to accommodate bulky exogenous substrates. In contrast to bovine complex I, bulky quinone analogues served as poor electron acceptors with Paracoccus NDH-1. These observations indicated that bovine complex I recognizes the substrate structure with poor specificity. The substituent effects in the 2- and 3-positions of the quinone ring on the electron-transfer activity with bovine complex I differed significantly between Q2 and DB series despite having the same total number of carbon atoms in the side chain. The inhibitory effect involving Q2 due to its geranyl side chain was markedly diminished by structural modifications of the quinone ring moiety. These findings indicate that the side chain plays a specific role in the redox reaction and that the quinone ring and side-chain moieties contribute interdependently to binding interaction. Moreover, structural dependency of the proton-pumping activity of the quinone analogues was comparable to that of the electron-transfer activity with bovine complex I, indicating that the mechanism of redox-driven proton-pumping does not differ depending upon the substrate structure. 相似文献
83.
K. Shigihara K. Kawasaki S. Yamamura A. Takemoto T. Yagi Y. Mitsui 《Photonics Technology Letters, IEEE》2003,15(5):640-642
The structure of an asymmetrically expanded optical field normal to the active layer was applied to 1020-nm ridge waveguide laser diodes in order to increase their maximum kink-free output power and reduce the aspect ratio of the output beams. As a result, a kink-free output power of more than 400 mW and an aspect ratio of less than 2.5 were achieved by this structure. Good reliability was also obtained at an output power of 300 mW at 50/spl deg/C. 相似文献
84.
85.
A Yoshitomi A Sato R Tamura T Suda T Yagi Y Nakano H Hayakawa K Chida 《Canadian Metallurgical Quarterly》1993,31(12):1606-1611
We report two cases of idiopathic interstitial pneumonia (IIP) with acute deterioration after bronchoalveolar lavage (BAL). Case 1 was a 54-year-old woman, and case 2 was a 75-year-old man. Both were diagnosed as having IIP, and hospitalized with complaints of high fever and dyspnea. After BAL, the degree of dyspnea increased. White blood cell count and lactate dehydrogenase were elevated, and PaO2 was decreased. Chest X-ray revealed consolidation of the upper lung fields and reticulo-granular shadows spreading through both lungs. BAL fluid examination showed an elevated neutrophil fraction (case 1: 6.5%, case 2: 35.2%), suggesting respiratory tract infection although bacteria could not be detected. Case 1 died of respiratory failure despite corticosteroid therapy. Autopsy revealed diffuse alveolar damage with focal pneumonia in the right S6 corresponding to the upper lobe consolidation. Case 2 improved after antibiotic therapy. These findings suggest that aspiration of infected fluid during BAL can cause acute exacerbation of IIP. It is important to recognize that the BAL procedure can induce an acute exacerbation of IIP. 相似文献
86.
SA Filppula AI Yagi SH Kilpel?inen D Novikov DR FitzPatrick M Vihinen D Valle JK Hiltunen 《Canadian Metallurgical Quarterly》1998,273(1):349-355
rECH1, a recently identified rat cDNA (FitzPatrick, D. R., Germain-Lee, E., and Valle, D. (1995) Genomics 27, 457-466) encodes a polypeptide belonging to the hydratase/isomerase superfamily. We modeled the structure of rECH1 based on rat mitochondrial 2-enoyl-CoA hydratase 1. The model predicts that rECH1p has the hydratase fold in the core domain and two domains for interaction with other subunits. When we incubated 3,5,8,11, 14-eicosapentaenoyl-CoA with purified rECH1p, the spectral data suggested a switching of the double bonds from the Delta3-Delta5 to the Delta2-Delta4 positions. This was confirmed by demonstrating that the product was a valid substrate for 2,4-dienoyl-CoA reductase. These results indicate that rECH1p is Delta3,5-Delta2,4-dienoyl-CoA isomerase. Subcellular fractionation and immunoelectron microscopy using antibodies to a synthetic polypeptide derived from the C terminus of rECH1p showed that rECH1p is located in the matrix of both mitochondria and peroxisomes in rat liver. Consistent with these observations, the 36,000-Da rECH1p has a potential N-terminal mitochondrial targeting signal as well as a C-terminal peroxisomal targeting signal type 1. Transport of the protein into the mitochondria with cleavage of the targeting signal results in a mature mitochondrial form with a molecular mass of 32,000 Da; transport to peroxisomes yields a protein of 36,000 Da. 相似文献
87.
Wakahara Y. Fujioka M. Kukuta H. Yagi H. Sakai S.-I. 《Communications Magazine, IEEE》1993,31(8):32-37
A method for detecting interactions among services and service features in communication systems is proposed. The method uses three types of knowledge: knowledge for clarifying and completing the specification of each feature, knowledge for identifying the implicit relationships among the features, and knowledge for detecting the interactions from the extended feature specifications derived from the first two types of knowledge. Six types of nontrivial interaction are outlined 相似文献
88.
T Inada T Sugita I Dobashi A Inagaki Y Kitao G Matsuda S Kato T Takano G Yagi M Asai 《Canadian Metallurgical Quarterly》1995,5(3):113-116
Cycads, the most primitive of the living gymnosperms, have been used and continue to be used for food and medicinal purposes by many cultures, although toxins must be removed before ingestion. In our quest to identify tropical plants that contain inhibitors of the cytochrome P-450 aromatase and thus may be efficacious in treating estrogen-dependent tumors, we have screened extracts from 5 species of cycad folia encompassing 3 genera: Cycas cairnsiana F. Muell., Cycas revoluta Thunb., Cycas rumphii Miq., Dioon spinulosum Dyer and Encephalartos ferox Bertol. All extracts were found to contain inhibitors of the human enzyme. 相似文献
89.
L. B. Evans J. F. Boston H. I. Britt P. W. Gallier P. K. Gupta B. Joseph V. Mahalec E. Ng W. D. Seider H. Yagi 《Computers & Chemical Engineering》1979,3(1-4):319-327
The paper presents an overview of ASPEN (Advanced System for Process Engineering) which is a next-generation process simulator and economic evaluation system. The system is presently under development for use in engineering of fossil energy conversion processes. 相似文献
90.
Integration of well maintained application programs for process design is attempted using an in-house Data Base Management System. The main reason for taking the present approach is to keep the reliability of the existing application programs and to minimize revision work. Through the authors' experience described in this paper, it was found that the proposed way of integration by means of DBMS is to be recommended for these purposes when the number of application programs is small. 相似文献