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41.
S Ohwada S Nakamura Y Kawashima I Kobayashi T Ohya Y Iino Y Morishita 《Canadian Metallurgical Quarterly》1997,44(17):1385-1389
BACKGROUND/AIMS: A successful left trisegmentectomy and tumor thrombectomy for hepatocellular carcinoma (HCC) of the right third branches in the remnant liver is described. METHODOLOGY: In this case, the hepatocellular carcinoma originated in the internal segment of an HBs- and HBe-Ag positive cirrhotic liver, involved the portal vein of the umbilical portion across the portal trunk to the contralateral third branches, and had many metastatic nodules in the anterior segment of the liver. To remove tumor thrombi by directly visualizing the lumen of the third branches of the portal vein, the portal trunk to the anterior branch of the portal vein was completely isolated by transecting the hepatic parenchyma along the intersegmental plane through a hilar approach. Tumor thrombi were removed by incising the portal trunk toward the anterior branch of the portal vein. Portal flow to the remnant liver was restored preceding liver resection to preserve hepatic function. After division of the anterior Glissonean code, the left trisegment and caudate lobes of the liver were resected. RESULTS: The patient was discharged 10 weeks after surgery and remained well for the first six months thereafter. Recurrent tumors, however, appeared in the remnant liver 7 months after surgery. CONCLUSIONS: This procedure may be applicable in cases of HCC with portal tumor thrombi extending into the third branches in the remnant liver. 相似文献
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Yasuhiko Nomura Yoshitaka Morishita Shigeo Goto Yoshifumi Katayama 《Journal of Electronic Materials》1994,23(2):97-100
We have grown GaAs nano wire structures (45 × 20 nm2) buried in AIAs layers by lateral metalorganic molecular beam epitaxy on the terraced sidewalls of mesa-grooved (-1-1-1)B
substrates. The growth of GaAs occurred primarily on the sidewall of the mesa-grooves and not on the (-1-1-1)B surface for
arsenic pressures greater than 2.0 × 10−3 Pa at a substrate temperature of 480°C. An (0-1-1) facet formation during the lateral epitaxy at the intersection region
between the bottom (-1-1-1)B surface and the (1-2-2)A sidewall has been directly observed by real-time scanning microprobe
reflection high-energy electron diffraction. The growth rate on the (0111) facet was estimated from the variation of its width
with growth time. 相似文献
44.
Two cases of sacral chordoma in a 7-year, 9-month-old boy and a 3-year, 4-month-old boy are presented. In addition to the typical histology of conventional chordoma, both tumors showed the less differentiated sarcomatoid appearance of atypical chordoma in the major portion. Immunohistochemically, in both cases neoplastic cells in areas of conventional as well as atypical chordoma were positive for keratins (CAM 5.2, AE1 and AE3), epithelial membrane antigen, vimentin, S-100 protein, carcinoembryonic antigen, and glial fibrillary acidic protein. Both patients underwent resection of the tumor and chemotherapy. In comparison with conventional chordomas in adults, however, these two tumors showed more aggressive clinical course and were less amenable to therapeutic control. The older boy died of multiple metastasis 1 year after initial diagnosis. At the last follow-up, 15 months after initial diagnosis, the younger boy was alive, but with recurrent and metastatic disease of the left parasacral area and chest wall. Our studies of these two cases and the reported cases suggest that sacral chordoma in children has distinctive clinicopathologic features denoting a highly aggressive tumor and that it should be treated as such. 相似文献
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A fractional dissolution on the oxymethylene copolymer obtained by the iodine-initiated, solid-state copolymerization of the tetraoxane–1,3-dioxolane-methylal system has been carried out using a mixed solvent which consists of tetrachloroethane, phenol, and cyclohexanol. On the fractional dissolution, the oxymethylene copolymer was divided mainly into two parts: one was the copolymer containing a larger amount of ethylene oxide unit in its main chain and having lower molecular weight; the other was copolymer containing a smaller amount of ethylene oxide unit and having a higher molecular weight. It was reasonably concluded that in this copolymerization system, the reaction proceeds from the surface to the center of the tetraoxane crystal to give a divided copolymer due to the heterogeneous properties such as copolymer composition and molecular weight. 相似文献
47.
MJ Mann R Morishita GH Gibbons HE von der Leyen VJ Dzau 《Canadian Metallurgical Quarterly》1997,172(1-2):3-12
Manipulation of the genetic machinery of cells both in vitro and in vivo is becoming an ever more important means of elucidating pathways of molecular and cellular biochemistry. In addition, gene therapy has been proposed as a novel and potentially powerful treatment for both inherited and acquired diseases. Successful gene transfer and gene blockade generally depend on high efficiency delivery of exogenous DNA or RNA into living cells, and much effort has therefore been focused on the development of methods for achieving this delivery in a safe and effective manner. We describe here our application of fusigenic Sendai virus (HVJ)-liposome technology toward the effective delivery of DNA into vascular smooth muscle cells (VSMC) in cell culture. Cellular uptake and intracellular distribution of oligodeoxynucleotide (ODN) after transfection with HVJ-liposome complexes was characterized using fluorescent (FITC)-labeled ODN, and the biologic effect of HVJ-liposome mediated transfection was demonstrated via inhibition of DNA synthesis in cultured VSMC using antisense ODN against basic fibroblast growth factor. 相似文献
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The effects of the onset of lasing on the I-V characteristics, the impedance characteristics and the light modulation characteristics of laser diodes have been discussed by introducing the rate equations which involve carrier diffusion process in the active layer interacting with the radiation field intensity. The static I-V characteristics exhibit a kink at lasing threshold current, reflecting the decrease of effective lifetime of carriers. Effective carrier lifetimes decrease with increasing light intensity, which results in a steep attenuation of injected carrier density in the active region. The impedance and light modulation characteristics are obtained in the small signal approximation. The small signal light modulation characteristics depend strongly on whether the laser diode is excited by the constant current modulation or the constant voltage modulation. The impedance is changed drastically by the onset of lasing and exhibits a resonance which coincides exactly with the optical modulation resonance frequency. 相似文献