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I Nagata H Kikuchi S Yamagata S Miyamoto T Kaneko R Asato 《No shinkei geka. Neurological surgery》1990,18(12):1115-1120
12 giant intracranial aneurysms were studied by MRI. Intraluminal thrombosis was observed in 9 aneurysms. Thrombosis was found more frequently in larger aneurysms. Thrombi were formed posteriorly or inferiorly in the lumen of 4 among 5 IC-cavernous aneurysms. Location of the neck of the aneurysms and stagnation of blood flow influenced by gravity may be causative factors determining the location of thrombi. In 6 aneurysms intraluminal thrombi were inhomogeneous on MRI, suggesting that the thrombi had been formed at different times. New thrombi were formed between the aneurysmal wall and the old thrombus in 3 cases. Dissection of the aneurysmal wall by residual blood flow in the lumen or hemorrhage in the aneurysmal wall may be one of the growth mechanisms of giant intracranial aneurysms. 相似文献
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ASTROCYTE-CONDITIONED MEDIUM INDUCES BLOOD-BRAIN BARRIER PROPERTIES IN ENDOTHELIAL CELLS 总被引:6,自引:0,他引:6
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Kazumasa Miyake Atsushi Tatsuguchi Mikiko Tachibana Masanobu Kusunoki Yoko Shinji Kei Shinoki Tetsuro Hiratsuka Kazuhiro Nagata Hitoshi Nishigaki Seiji Futagami Ken Wada Taku Tsukui Toshiro Yoshiyuki Akira Tokunaga Takashi Tajiri Choitsu Sakamoto 《Digestive endoscopy》2004,16(2):172-175
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia. 相似文献
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M Ishikawa H Kikuchi I Nagata S Yamagata W Taki Y Yonekura S Nishizawa Y Iwasaki T Mukai 《Neurologia medico-chirurgica》1990,30(6):377-381
To investigate the value of direct measurement of the rate constants by performing 18F-labeled fluorodeoxyglucose (FDG) studies of glucose consumption in human gliomas in vivo, a kinetic method with 3- and 4-parameter rate constant models for FDG uptake was used to analyze data from dynamic scans obtained by positron emission tomography after injection of FDG into 14 patients with glioma. The results were compared with those obtained by the autoradiographic method using 3- and 4-parameter rate constant models. There were no significant differences in the glucose consumption calculated by the four different methods both in the gliomas and in the contralateral intact cortex. It was found that the rate constant k4* could be neglected in calculation of glucose consumption in gliomas as well as in the contralateral intact cortex. The rate constant k3*, an index of hexokinase function, was higher in malignant gliomas than in benign gliomas and was close to that in the contralateral cortex. This study indicates that the 3-parameter autoradiographic method, which is the most common one used in clinical practice, is reliable for the calculation of glucose consumption in human gliomas. Furthermore, direct measurement of the regional rate constants for FDG by the kinetic method was found to be useful for evaluation of the biochemical and physiological characteristics of human gliomas in vivo. 相似文献
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Nelson T Yamagata Bruce L Miller Duncan McBride Linda Chang Francis Chiang Diana Nikas Diane Osborne Steven D Buchthal 《Journal of neuroimaging》1994,4(1):23-28
The chemical characteristics of 10 neoplastic and 11 infectious brain masses were studied by in vivo 1H magnetic resonance spectroscopy. In tumors, peak height ratios of n-acetyl-L-aspartate to choline were decreased compared to those in normal brain tissue and infectious masses (p < 0.02), but the ratios in normal brains and those with infections did not differ. N-acetyl-L-aspartate—to-creatine/phosphocreatine ratios were significantly lower in infectious masses and tumors compared to normal brain tissue (p = 0.003). However, in progressive multifocal leukoencephalopathy, N-acetyl-L-aspartate appeared relatively unchanged. Lactate was greater than choline in 9 of 11 brains with infection, 0 of 14 control brains, and 1 of 10 tumors. Lactate-to-choline ratios were significantly elevated in infectious masses compared with tumors (p < 0.01). 1H magnetic resonance spectroscopy is promising for the noninvasive diagnosis of focal brain masses. 相似文献
9.
Impact of portal venous pressure on regeneration and graft damage after living-donor liver transplantation. 总被引:4,自引:0,他引:4
Shintaro Yagi Taku Iida Kentaro Taniguchi Tomohide Hori Takashi Hamada Koji Fujii Shugo Mizuno Shinji Uemoto 《Liver transplantation》2005,11(1):68-75
Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels. 相似文献