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51.
N Yoshioka  S Tominaga 《Canadian Metallurgical Quarterly》1997,47(5):460-5; discussion 465-6
BACKGROUND: Although the most common technique of cerebral revascularization is superficial temporal artery to middle cerebral artery bypass, we occasionally encounter a situation in which the ipsilateral superficial temporal artery is not available. Treatment may require several techniques including long vein graft bypass. METHODS: A 54-year-old man experienced transient ischemic attacks, and cerebral angiography revealed occlusion of the right common carotid artery. Cerebral blood flow study revealed reduced perfusion reserve capacity of the right cerebral hemisphere. We applied an omental free flap to the brain surface using the contralateral superficial temporal vessels as recipient vessels. RESULTS: Cerebral blood flow study revealed improvement of perfusion reserve capacity. Cerebral angiography revealed good collateral circulation from the omentum to the brain. The patient has not experienced a transient ischemic attack, following additional ligation of the occipital artery 13 months after the first operation. CONCLUSIONS: Because an omental flap has a long pedicle and its circulation can be monitored easily, this method is safe and as effective as a long bypass graft in a patient such as ours in whom the ipsilateral superficial temporal artery is not available for anastomoses.  相似文献   
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We have synthesized mesoporous silica (MPSi) as a novel type of inorganic filler for polyether-based electrolytes and have characterized the effect of addition on ionic conduction. Both poly(ethylene oxide) (PEO) and PMEO composites filled with MPSi showed higher ionic conductivity than the original and the composites filled with particle silica (pSiO2). It was considered that the increase is caused by the difference in the surface area between MPSi and pSiO2. In the PEO composites, the addition of MPSi gave rise to the reduction of crystal PEO and crystalline complex domains. The glass transition temperature of the PMEO composites increased with the addition of the MPSi, in spite that the conductivity increased with increasing the filler contents. It has been suggested that the Lewis acid-base interactions between ions, ether chains and filler surface strongly affect on the ionic conduction in the composite electrolytes.  相似文献   
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We studied the long-term outcome of percutaneous isolated hepatic perfusion (PIHP) for patients with hepatocellular carcinoma. This study included 31 patients with Stage IVA and 5 with IVB disease treated by PIHP until December, 1997. The mean age and tumor diameter were 55 and 7.7 cm, respectively. Twenty-two had portal vein invasion, 13 had hepatic vein invasion, and all patients had multiple intrahepatic metastases of more than 5 tumor foci. The PIHP with adriamycin or cisplatin was undertaken in a total of 50 treatments in these 36 patients. CR was observed in 6 and PR in 13 with an overall response rate of 59%, excluding 4 patients who were not evaluable. Five of 6 patients with CR remain free of disease at 7 to 54 months after the first treatment. The overall survival rate was 67% at 1 year and 32% at 5 years. The survival rates of Stage IVA patients (1-year = 71%, 5-year = 36%) were higher than Stage IVB patients (1-year = 20%, 5-year = 0%). The 5-year survival rates of patients with vascular invasion (Vp1-3 = 23%, Vv1-3 = 8%) were lower than those without it (Vp0 = 47%, Vv0 = 51%). These results indicated that PIHP achieved a 5-year survival rate of approximately 40% in patients with multiple advanced hepatocellular carcinoma in the absence of distant organ metastases and marked vascular invasion, and yielded complete long-term remission in some of these patients.  相似文献   
54.
Mutation of the adenomatous polyposis coli (APC) gene is frequently found in colorectal tumors from both familial adenomatous polyposis (FAP) and non-FAP patients. Analysis of APC mutation is time-consuming and costly due to the large size of the APC gene. As the majority of APC mutations result in the truncation of gene products, the detection of truncated APC proteins may be used as a screening method for APC mutations. The aim of this study is to establish a practical method of detecting truncated APC proteins for the screening of APC mutations. APC proteins in human colorectal cancer cell lines were analyzed by western blotting. Truncated APC proteins were expressed in all of the colorectal cancer cell lines studied. Two species of truncated APC proteins were expressed in two cell lines. Western blotting is a rapid, reliable screening method for APC mutations and provides information on both alleles.  相似文献   
55.
A method to treat lower limb ischemia associated with the insertion of an intraaortic balloon catheter is herein reported. A low dose of prostaglandin E1 was administered into the descending aorta continuously from the tip of the intraaortic balloon catheter. Immediately after the administration of prostaglandin E1 in patients whose lower limbs were ischemic due to obstruction with the catheter, the peripheral circulation of the ischemic limbs recovered with minimal changes in the systemic arterial blood pressure. This method is simple and noninvasive and was found to induce a satisfactory effect.  相似文献   
56.
In this study, morphologic changes in brain lesions initiated by moderate lateral fluid percussion injury in rats were investigated chronologically using high-resolution magnetic resonance imaging (MRI) and histopathologic methods. Rats were subjected to moderate fluid percussion injury (average 2.80 +/- 0.48 atmospheres) over the exposed dura overlying the right parietal cortex. MRI obtained in vivo were compared with corresponding pathologic findings at 1, 6, and 24 h and at 3, 6, 14 and 80 days after injury. T2-weighted images showed scattered low-signal intensity in the injured cortex within a few hours after injury, whereas histologic findings revealed intraparenchymal hemorrhages. T2-weighted images of the ipsilateral cerebral cortex and/or corpus callosum showed a high-signal-intensity area 4 h after injury. The high-signal-intensity area became largest in size between 6 and 24 h, then declined gradually, and almost disappeared 14 days after injury. Histologic examination revealed pyknosis, retraction of the cell body of neurons with vacuolated neuropil in the corresponding regions 6 and 24 h after injury, and cystic necrosis 14 days after injury. The location and extent of these pathologic changes were depicted accurately by MRI in vivo. In the hippocampus, pyknosis and retraction of the cell body of pyramidal neurons were observed on the injured side 24 h after injury, and the number of neurons in the CA1 and CA2-CA3 regions decreased significantly on the same side by 14 days after injury. It is concluded that morphologic changes in the brain following experimental traumatic brain injury in rats are detectable in vivo by high-resolution MRI, and that MRI may be useful for the evaluation of treatment effects in experimental brain injury.  相似文献   
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This article proposes dichromatic reflection models adequate for describing surface-spectral reflectances of a variety of materials. the standard dichromatic reflection model for inhomogeneous materials assumes that light reflected from an object's surface is decomposed into two additive components: the body reflection and the interface reflection, which is independent of wavelength. First, we present a method for testing the adequacy of this standard model based on the observations of surface-spectral reflectances. the standard dichromatic reflection model is adequate for many materials. However, the test results point out that there are some cloths for which the standard model is inadequate, and metals that have only the interface reflection. Next, we extend the standard model to have an interface reflection component that depends on wavelength. an algorithm is presented for estimating two reflectance functions in the generalized model. Moreover, a dichromatic reflection model specialized for only the specular reflection is defined for approximating metal's reflection. the reflection characteristics are analyzed using a chromaticity diagram. It is concluded that surfacespectral reflectances of most materials are described by three types of the dichromatic reflection model. © 1994 John Wiley & Sons, Inc.  相似文献   
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