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71.
Uno T Yasuda S Aruga T Isobe K Machida N Kawakami H Kawata T Miyazaki M Ito H 《Anticancer research》2002,22(5):3013-3017
BACKGROUND: To assess the locoregional control, survival and toxicities of combined intermediate-dose pre-operative irradiation and surgery for rectal cancer patients. MATERIALS AND METHODS: Forty-two patients with adenocarcinoma of the rectum underwent intermediate-dose pre-operative radiotherapy. The median age was 58 years. the prescribed dose was 30.6 Gy to the whole pelvis, while a boost of 4 x 3 Gy to the primary tumor was added. The calculated linear-quadratic dose was 52 Gy. RESULTS: Failure as a first site was pelvic in 2 and distant in 11. The crude pelvic failure rate was 9.5%. The 3- and 5-year overall survival was 75% and 63%, respectively. Pre-operative radiotherapy was well-tolerated by all. No anastomotic breakdown was seen. Nor was any death attributable to any adverse effects of the treatment. CONCLUSION: The present results suggested that pre-operative intermediate-dose radiotherapy is effective in preventing pelvic recurrence in rectal cancer patients with acceptable toxicities. 相似文献
72.
Noguchi Y Murakami T Kim T Hori M Osuga K Kawata S Okada A Sugiura T Tomoda K Narumi Y Nakamura H 《Journal of computer assisted tomography》2002,26(6):981-987
PURPOSE: The technique of double-echo chemical shift gradient echo magnetic resonance imaging (MRI) with the fast low-angle shot (double-echo FLASH) sequence provides in-phase and opposed-phase images in a single breath hold. The purpose of this study was to evaluate the efficacy of dynamic MRI with double-echo FLASH imaging for the detection of hypervascular hepatocellular carcinoma by comparing it with dynamic helical computed tomography (CT) imaging with double arterial phase. MATERIALS AND METHODS: Twenty-nine patients with 67 hypervascular hepatocellular carcinoma nodules who underwent both dynamic MRI with double-echo FLASH imaging (repetition time/echo time/flip angle: 160/3.6, 7.0/80 degrees ) and dynamic helical CT imaging with double arterial phase were enrolled in the study. For dynamic MRI, precontrast, arterial, portal venous, and equilibrium phase images were obtained before and approximately 19, 60, and 120 seconds, respectively, after intravenous injection of 0.1 mmol/kg of gadopentetate dimeglumine at a rate of 2 ml/s. For dynamic CT imaging, quadraphase images, including early arterial, late arterial, portal venous, and equilibrium phases, were obtained serially approximately 20, 30, 70, and 180 seconds, respectively, after intravenous administration of 2 ml/kg of 300 mgI/ml of nonionic contrast medium at a rate of 5 ml/s. Three masked observers independently interpreted images obtained with each technique in random order, separately and without patient identifiers. Sensitivity and positive predictive values as well as the area below the alternative-free response receiver operating characteristic curve (Az) for each imaging technique were calculated and compared statistically. RESULTS: Mean sensitivity and positive predictive values of MRI for hypervascular hepatocellular carcinoma were 48% and 94%, respectively, and those of CT imaging were 47% and 91%, respectively. In 11 (38%) of the 29 patients, at least one observer judged dynamic MRI to be superior, whereas in 5 patients (17%), dynamic CT was judged to be superior. There was no significant difference in the sensitivity and positive predictive values between these techniques (p > 0.05). There was no significant difference either in mean Az values between CT (0.55) and MRI (0.57) (p = 0.61). CONCLUSION: Dynamic MRI with double-echo FLASH imaging can detect hypervascular hepatocellular carcinoma as well as dynamic helical CT imaging with double arterial phase. 相似文献
73.
Yamazaki H Tomoda K Shiomi H Maeda M Kawata S Okada A Murakami T Nakamura H Tanaka E Inoue T Inoue T 《Radiation Medicine》2002,20(1):25-32
This study examined the applicability of endovascular brachytherapy to larger del arteries such as the abdominal aorta and iliac artery. Endovascular brachytherapy using an Ir-192 HDR source was administered 11 times to nine patients who had undergone percutaneous transluminal angioplasty (PTA) between 1995 and 1999. The follow-up lasted 13 to 55 months after treatment (median, 24 months). Eight of the 11 lesions have been controlled so far. Although one case developed thrombus inside the stent five months later, recanalization was achieved by means of retreatment. One patient who underwent low-dose irradiation (6 Gy) without stent implantation showed restenosis five months after treatment. We used a centering catheter that did not block the blood stream for exact centering of the radiation source in larger vessels such as the abdominal aorta. Although endovascular brachytherapy is a promising and safe procedure, careful follow-up is needed to detect untoward reactions such as thrombosis. 相似文献
74.
Proteins are secreted from animal cells by either a constitutive or a regulated pathway. When cDNA of nerve growth factor (NGF) was introduced into PC12 cells, these cells produced and secreted active NGF, where NGF was secreted not only in constitutive but also in activity-dependent regulated way according to the results of pulse-chase and ELISA studies. The regulated secretion was caused by depolarization, cyclic AMP analogue, or beta-adrenergic agonist but not by glutamate or carbachol. Because these transfected cells differentiated into a morphology indistinguishable from that incubated with NGF protein, we next compared the secretion pathways of NGF from PC12 cells at different stages of the differentiation. NGF was secreted in both constitutive and regulated way at 2 and 7 days after the transfection of NGF-cDNA, but the constitutive secretion of NGF from the more differentiated cells of Day 7 was decreased and mature NGF tended to accumulate in the cells. These results indicate that the neurotrophin secretion mechanism is intimately regulated in the course of the differentiation of PC12 cells. Such a change in the protein secretion pathway might have an profound role in the development of neurons. 相似文献
75.
The composition of the volatile oil from Sinapis Semen, dried seeds of Brassica hirta (Cruciferae), have been investigated using capillary GC and GC/MS. The important odor-active compounds in the oil were also detected by means of GC-olfactometry (GC-O) and aroma extract dilution analysis (AEDA). The oil was found to contain 68 components, representing 95.36% of the total oil. The main constituents were 4-hydroxy-benzeneacetonitrile (29.63%), palmitic acid (14.55%), linoleic acid and oleic acid (9.67%). The AEDA and GC-O analyses showed that heptanal, phenylethylalcohol, (2E)-octenal and (2E, 4E)-dodecadienal are to a large extent responsible for the characteristic flavor of Sinapis Semen. 相似文献
76.
77.
Mizuno K Okada M Murakami T Kamata A Zhu G Kawata Y Wada K Kaneko S 《Epilepsy research》2000,40(2-3):187-195
To clarify the mechanisms of action of carbamazepine (CBZ), we investigated the effects of CBZ on acetylcholine (ACh) release and metabolism in rat striatum and hippocampus. Acute administration of effective dose of CBZ (25 mg/kg) increased both striatal and hippocampal extracellular levels of ACh, whereas a supraeffective dose of CBZ (50 mg/kg) did not affect the levels and a toxic dose of CBZ (100 mg/kg) decreased the extracellular ACh levels in both brain regions. Both acute and chronic administrations of CBZ (25 and 50 mg/kg, mg/kg per day) increased intracellular ACh levels in striatum and hippocampus. The striatal intracellular ACh levels were decreased by both acute and chronic administrations of CBZ (100 mg/kg, mg/kg per day), whereas the hippocampal intracellular ACh levels were not affected. The effective CBZ concentration did not affect cholinesterase activity, whereas supraeffective CBZ concentration reduced it weakly. Effective dose of CBZ enhanced ACh release and synthesis; however, supraeffective doses of CBZ reduced ACh release and synthesis without enhancement of ACh degradation, indicating that CBZ has biphasic effects on ACh release and synthesis. Thus, the present findings, the slight stimulation of ACh function by effective dose of CBZ, are involved, at least partially, in the antiepileptic and mood stabilizing mechanisms of action of CBZ. 相似文献
78.
Tanaka M Tanaka K Tsuji S Kawata A Kojima S Kurokawa T Kira J Takiguchi M 《Journal of the neurological sciences》2001,188(1-2):61-65
OBJECTIVE: To determine a peptide that reacts with cytotoxic T cells (CTL) of patients with paraneoplastic cerebellar degeneration and anti-Yo antibodies with either HLA A24 or B27 supertype. METHOD: We studied CTL activity of four patients, three were HLA A24-positive and one did not have HLA A24 but had B27 supertype. After an incubation of mononuclear cells with or without peptide and IL-2, CD8-rich fraction was prepared by treatment with Magnetic Cell Sorting system (MACS) twice. CTL activity was calculated by 51Cr release from transfectant, C1RA*2402 as target cells. The peptide-binding assay was examined by flow cytometry. RESULTS: Two of three HLA A 24-positive patients demonstrated CTL activity against the Yo peptide, AYRARALEL. CTL activity was found to be 19.5% and 11.7% at the effector/target (E/T) ratio of 23:1 and 11:1, respectively. A patient who did not have HLA A24 but had A2 and B27 supertype possessed a CTL activity of 19.4% with 15:1 as E/T ratio. The peptide could bind to HLA A*2402 molecules but not to A*0201. CONCLUSIONS: We showed CTL activity in two of three Japanese patients with HLA A24 by using HLA A*2402 transfectant cells as the target. In addition, we identified the first Japanese patient who had B27 supertype, and suggested that the same peptide, AYRARALEL, could be recognized by CTL in this patient. 相似文献
79.
Microwave coagulation therapy with interruption of hepatic blood in- or outflow: an experimental study 总被引:2,自引:0,他引:2
Takamura M Murakami T Shibata T Ishida T Niinobu T Kawata S Shimizu J Kim T Monden M Nakamura H 《Journal of vascular and interventional radiology : JVIR》2001,12(5):619-622
PURPOSE: To determine how interruption of hepatic blood in- or outflow affects the coagulation diameter of microwave coagulation therapy (MCT) in the liver. MATERIALS AND METHODS: Laparotomic MCT at 60 W for 1 minute was performed in 11 Landrace pigs. MCT was performed under six different conditions: without occlusion (Group N; in seven lobes of seven pigs); with occlusion of the hepatic artery (Group A; in five lobes of five pigs); with occlusion of the portal vein (Group P; in five lobes of five pigs); with occlusion of the hepatic artery and portal vein (Group AP; in six lobes of six pigs); with occlusion of the hepatic vein (Group V; in five lobes of four pigs); and with occlusion of the hepatic artery and vein (Group AV; in seven lobes of seven pigs). The maximum diameters for each group were compared. RESULTS: The coagulation diameters (mean +/- SD) were 8.5 mm +/- 2.0, 10.0 mm +/- 1.6, 14.3 mm +/- 2.5, 14.4 mm +/- 2.4, 13.0 mm +/- 0.8, and 14.4 mm +/- 1.5 for Groups N, A, P, AP, V, and AV, respectively. The coagulation diameters for groups P, AP, V, and AV were statistically larger than those for groups N and A (P < .05). There was no significant difference between the coagulation diameters of Groups P, AP, V, and AV. CONCLUSION: The coagulation diameter depends mainly on the portal venous flow. In addition of direct interruption of the portal vein, interruption of the hepatic vein can also result in a substantial increase in the coagulation diameter. 相似文献
80.