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31.
Toshihisa Inoue MD Shigeru Watanabe MD Yoshiaki Masuda MD Katsuya Yoshida MD Hitoshi Imai MD Yasuo Imazeki MD Yoshiaki Ishizuya MD Masashi Koga MD Hirotoshi Kato MD Hiroo Ikehira MD Yukio Tateno MD 《Clinical imaging》1996,20(4):262-268
The magnetic resonance phase-contrast technique for the measurement of flow velocity and volume in true and false lumens was studied in six patients with chronic dissecting aneurysms. Phase-contrast images were obtained at a level perpendicular to the dissecting aneurysms of the descending aorta. As the maximum diameter of aneurysms increased, the ratio of the cross-sectional area of the false to the true lumen increased and the peak average velocity in the true lumen during systole was decreased. This technique proved invaluable for determining prognosis and operability for this condition. 相似文献
32.
Immunoreactive opsin and glial fibrillary acidic protein in persistent hyperplastic primary vitreous
An 8-month-old boy had an anterior type of persistent hyperplastic primary vitreous in the right eye. Results of needle biopsy, performed because of elevated intraocular pressure, disclosed clusters of blastic cells. The eye was enucleated on the suspicion of retinoblastoma. Histological examination showed retrolental fibrovascular tissue and retinal dysplasia. Immunoreactive opsin was detected in the innermost structures and in photoreceptor-like cells of rosettes. We conclude that photoreceptor cells differentiated to express opsin, even when neighbouring cells were abnormally arranged. An immunocytochemical study of glial fibrillary acidic protein demonstrated glial proliferation in the inner layer of the retina but not in the preretinal space. 相似文献
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A Kagaya H Fukuda K Yoshida M Endo T Himi H Niwayama Y Masuda Y Inagaki K Suzuki T Suhara 《Kaku igaku. The Japanese journal of nuclear medicine》1992,29(9):1099-1106
To evaluate the effect of smoking on nonrespiratory function in the lung, a dynamic PET with 13NH3 in the lung was performed in 18 normal volunteers without lung disease nor congestion (9 non-smokers, 4 exsmokers, 5 smokers). After intravenous bolus injection of 13NH3, twenty serial 5.5-second scans followed by six 30-second scans were performed. Regions of interests were assigned on the ventral, lateral and dorsal part of the right lung and time-activity curves were generated through 26 images. The activity curve demonstrated a biexponential clearance from the lung with fast and slow component. The retention fraction (RF), fractional size of the slow component, was calculated, and the half-times (t 1/2) of both components were also evaluated. A significant increase of RF and prolongation of t 1/2 of slow component were observed in smokers compared to non-smokers and exsmokers. However, no significant difference of RF nor t 1/2 of both components was observed between non-smokers and exsmokers. These results suggest that long term smoking may modify the pulmonary kinetics of 13NH3, but the change is reversible after cessation of smoking for one year or longer. 相似文献
35.
Follicular dendritic cells (FDC) in retroviral infection: host/pathogen perspectives 总被引:6,自引:0,他引:6
Gergory F. Burton Akihiro Masuda Sonya L. Heath Beverly A. Smith John G. Tew ras K. Szakal 《Immunological reviews》1997,156(1):185-197
Summary: Follicular dendritic cells (FDC) are found in the follicles of virtually all secondary lymphoid tissues. In health, these cells trap and retain antigens (Ag) in the form of immune complexes and preserve them for months in their native conformation. FDC thus serve as a long-term repository of extracellular Ag important for induction and maintenance of memory responses. In retroviral infection. FDC trap and retain large numbers of retroviral particles with profound effects on FDC. FDC-trapped retrovirus induces follicular hyperplasia, and conventional Ag trapped prior to infection are lost and new Ag cannot be trapped. Concomitantly, antibody-forming cells (AFC) specific for Ag lost from FDC decrease follow I by loss of specific serum antibody (Ab). Eventually, FDC die and follicular lysis occurs. From the pathogen perspective, binding to FDC is remarkably beneficial, bringing together virus and activated target cells that are highly susceptible to infection. Furthermore, FDC permit HIV to infect surrounding cells even in the presence of a vast excess of neutralizing Ab. Preliminary data suggest that FDC maintain virus infectivity - even when the virus cannot replicate. Thus retrovirus infection monopolizes FDC networks, thereby transforming the FDC Ag repository into a highly infectious retroviral reservoir. 相似文献
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Mitsuo Sawamoto Toshio Masuda Toshinobu Higashimura 《Macromolecular chemistry and physics.》1976,177(10):2995-3007
The bimodal molecular weight distribution (MWD) of the polymers and the polymerization rate in the cationic polymerization of styrene by CF3SO3H were studied under a variety of conditions. Both the decrease of the dielectric constant of the reaction mixture and the addition of a common-ion salt (Bu4N+SO3CF) reduced the polymerization rate and the formation of the higher molecular weight portion of the polymers (the high polymer). It appears that of the two propagating species the one which forms the high polymer is more ionically dissociated and more reactive in propagation. Salt effects indicate that in nitrobenzene the propagating species is a solvent-separated ion pair and/or a free ion. The effects of monomer concentration on the bimodal MWD have shown that there are different chain-breaking reactions for the two propagating species. The possibility that the monomer is complexed with one of the growing species is also discussed. 相似文献
39.
Uwai Y Masuda S Goto M Motohashi H Saito H Okuda M Nakamura E Ito N Ogawa O Inui K 《Journal of human genetics》2004,49(1):40-45
40.
Kazunori Akiyoshi Toshio Masuda Toshinobu Higashimura 《Macromolecular chemistry and physics.》1992,193(3):755-763
Block copolymerizations of 1-chloro-1-octyne (1-ClO) with several substituted acetylenes were examined by means of living polymerization. o-(Trifluoromethyl)phenylacetylene (o-CF3PA), o-(trimethylsilyl)phenylacetylene (o-Me3SiPA), 1-chloro-2-phenylacetylene (1-ClPA), p-butyl-o,o,m,m-tetrafluorophenylacetylene (p-BuF4PA), and tert-butylacetylene (t-BuA) were used as comonomers, and the MoOCl4-n-Bu4Sn-EtOH (mole ratio 1:1:1) catalyst, which is known to effect living polymerization of substituted acetylenes, was employed. When o-CF3PA and 1-CIPA were the comonomers in combination with 1-CIO, block copolymers were exclusively obtained in both orders of monomer addition. In the cases of o-Me3SiPA and p-BuF4PA as comonomers, the copolymerizations initiated from 1-CIO produced block copolymers selectively, whereas the homopolymers of o-Me3SiPA and p-BuF4PA also formed if the order of monomer addition was reversed. The pair of 1-CIO and t-BuA did not selectively yield block copolymers irrespective of the order of monomer addition. Thus, block copolymerization occurred between 1-CIO and monomers that show high “livingness” and close reactivities. 相似文献