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33.
S Uchida M Sumiya Y Muramatsu Y Ohmomo S Yamaguchi H Obata M Umebayashi 《Health physics》1988,55(5):779-782
Among the routes of gaseous I transfer to rice grains, direct deposition to the hull of rice plants and the subsequent transfer to brown rice and polished rice should be more critical than leaf absorption-translocation. A grain number normalized deposition velocity (Vs) is recommended as a key parameter to assess the amount of gaseous I deposited on the rough rice. This parameter is given as "iodine content per unit number of grain per unit time" divided by "iodine concentration per unit volume of the air." After the heading period the surface area of rough rice is almost constant but weight increases with time. Therefore, mass normalized deposition velocity (VD) varies with time. By introducing Vs instead of VD, the variations could be converged into narrow ranges. The contribution of gaseous I from the atmosphere to rough rice, brown rice and polished rice were estimated using Vs values obtained experimentally and gaseous I concentration in the air. 相似文献
34.
Y Fujimoto Y Hamamura K Inoue K Shirasuna M Urade M Sugiyama M Kogo Y Uchida T Matsuya 《Osaka Daigaku shigaku zasshi》1989,34(2):370-377
The radial forearm flap, or the forearm flap, is called "Chinese flap" for its development of the chinese doctors, and is originally designed for the correction to the post-burn contraction of the face and neck. The radial forearm flap is one of the fasciocutaneous flap, supplied by the radial artery, and transferred as a single-stage reconstruction micro-surgically. In oral and maxillofacial region, the deltopectral flap (D-P flap) and the pectralis major myocutaneous flap (P-M-M-C flap) are mainly used for the reconstruction. These flaps, however, are sometimes too bulky and limited to transfer, and more require two-stage operations. On the other hand, as the forearm flap being thin and pliable, some doctors use this flap micro-surgically at single-stage free flap reconstruction. Before two years, we have begun to transfer the radial forearm flap for the intra-oral reconstruction. The operation method is as follows. Design and Elevation of the Radial Forearm Flap 1. Using the ultrasonic doppler flow meter, the radial artery and the subcutaneous forearm veins are marked on the skin. 2. The flap is designed 20% larger according to the pattern to be reconstructed, with the distal section of the radial artery as an axis on the forearm and the median vein of forearm inclusively. 3. Before the operation, Allen test must be performed in order to determine whether the hand will survive without a radial arterial in-put. 4. The operation is performed with a arm tourniquet. The margin of the flap are incised down to the deep fascia, isolating and preserving the proximal subcutaneous veins as required.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
35.
Among 389 consecutive chronic alcoholics in whom a liver biopsy was performed for diagnostic purposes, nine patients (2.3%) had histological changes of "alcoholic foamy degeneration" (AFD), characterized by numerous small fat droplets in the swollen hepatocytes of the centrilobular area. In five cases, there were non-specific clinical features, while the other four cases presented acute hepatic decompensation with jaundice and a reduced prothrombin activity. Seven patients had high serum lipid concentrations including hypertriglyceridemia and hypercholesterolemia, which improved after withdrawal of alcohol intake. In conclusion, AFD has a broad clinicopathological spectrum including asymptomatic patients and other cases with severe liver decompensation manifested by jaundice and reduced prothrombin activity. AFD is usually associated with hyperlipemia. 相似文献
36.
Uchida Y Ohshima T Sasaki Y Suzuki H Yanai S Yamashita N Nakamura F Takei K Ihara Y Mikoshiba K Kolattukudy P Honnorat J Goshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(2):165-179
Collapsin response mediating protein-2 (CRMP2) has been identified as an intracellular protein mediating Semaphorin3A (Sema3A), a repulsive guidance molecule. In this study, we demonstrate that cyclin-dependent kinase 5 (Cdk5) and glycogen synthase kinase 3beta (GSK3beta) plays a critical role in Sema3A signalling. In In vitro kinase assay, Cdk5 phosphorylated CRMP2 at Ser522, while GSK3beta did not induce any phosphorylation of CRMP2. Phosphorylation by GSK3beta was exclusively observed in Cdk5-phosphorylated CRMP2, but barely in CRMP2T509A. These results indicate that Cdk5 primarily phosphorylates CRMP2 at Ser522 and GSK3beta secondarily phosphorylates at Thr509. The dual-phosphorylated CRMP2, but not non-phosphorylated or single-phosphorylated CRMP2, is recognized with the antibody 3F4, which is highly reactive with the neurofibrillary tangles of Alzheimer's disease. 3F4 recognized the CRMP2 in the wild-type but not cdk5-/- mouse embryonic brain lysates. The phosphorylation of CRMP2 at Ser522 caused reduction of its affinity to tubulin. In dorsal root ganglion neurones, Sema3A stimulation enhanced the levels of the phosphorylated form of CRMP2 detected by 3F4. Over-expression of CRMP2 mutant substituting either Ser522 or Thr509 to Ala attenuates Sema3A-induced growth cone collapse response. These results suggest that the sequential phosphorylation of CRMP is an important process of Sema3A signalling and the same mechanism may have some relevance to the pathological aggregation of the microtubule-associated proteins. 相似文献
37.
Yozo Miura Yuzo Morimoto Masayoshi Kinoshita 《Macromolecular chemistry and physics.》1974,175(12):3487-3493
2,4,6-Triphenyl-3,4-dihydro-s-tetrazin-1(2H)-yl ( 1 ) (1,3,5-triphenylverdazyl) was allowed to react with ethyl- and butyllithium, ethyl-, isopropyl-, and butylmagnesium bromide, as well as benzylmagnesium chloride to give the coupling products 2a–d . These results indicate that structures corresponding to 2 are present in the polymers resulting from vinyl monomers containing the verdazyl structure, if they are initiated with alkyllithium or a Grignard reagent. A reaction mechanism is discussed. 相似文献
38.
Yuzo Okumura Jiro Kudo Tohru Ikuta Satoshi Kurokawa Hiromi Ishibashi Hideo Okubo 《Inflammation》1985,9(2):211-219
The effects of
1-antitrypsin (
1,-AT),
1,-acid glycoprotein (
1AGP), and haptoglobin (Hp), the main constituents of-globulin and which belong to acute phase proteins, on NK activity were examined using K562 cells as the NK target cells. Among the three proteins,
1,-AT and
1AGP had inhibitory effects on NK activity for fast target K562 cells. The,-AT preparations having the same protein concentration and a different trypsin inhibitory capacity (TIC) had an equal effect. Although
1AT and
1,-AGP equally reduced the NK activity, the mechanism involved in the reduction differed, in that the effect of
1,-AT directed toward NK cells reduced their binding capacity with the target cells,
1,-AGP probably interacts with a cytotoxic factor secreted from NK cells following effector-target interaction. These studies suggest that each of the acute-phase proteins, which increase following inflammation, inhibits NK cell function by two distinct mechanisms. 相似文献
39.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
40.
Kawano S Morotomi T Toyono T Nakamura N Uchida T Ohishi M Toyoshima K Harada H 《Connective tissue research》2002,43(2-3):409-412
Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway. 相似文献