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31.
Kimiaki Hashiguchi Takato Morioka Fumiaki Yoshida Yasushi Miyagi Shinji Nagata Ayumi Sakata Tomio Sasaki 《Seizure》2007,16(3):238-247
OBJECTIVE: To investigate the correlation between scalp-recorded electroencephalographic (EEG) and electrocorticographic (ECoG) activities during ictal periods. METHODS: Simultaneous EEG and ECoG recordings with chronic subdural electrodes were performed in eight patients with partial epilepsy. RESULTS: In two cases where the ictal ECoG discharges originated in deep brain structures such as the hippocampus and interhemispheric surface of the frontal lobe, ictal discharges could not be detected on EEG until they expanded to the cortex of convexity. In four cases, the ictal onset zones were located in the lateral convexity. When synchronous or near synchronous ictal ECoG discharges with amplitudes of 200-2000muV were recorded on more than 8-15cm(2) of cortex, corresponding discharges were recorded on EEG in these four cases. However, in a case of frontal lobe epilepsy, asynchronous ictal ECoG discharges were recorded on 10 electrodes of convexity but no ictal EEG activity was recorded. Furthermore, in two frontal lobe epilepsy cases, ictal EEG discharges did not always reflect the ictal ECoG spike, but occasionally reflected slow background ECoG activity around the ictal discharges. CONCLUSIONS: Multiple factors such as the width of the cortical area involved, amplitude of ictal discharges and degree of synchronization of electrical potentials play important roles in the appearance of ictal EEG recordings, and the relationship between ictal EEG and ECoG is not straightforward. 相似文献
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33.
Keisuke Mitsuoka Sosuke Miyoshi Yukio Kato Yoshihiro Murakami Rie Utsumi Yoshiyuki Kubo Akihiro Noda Yukio Nakamura Shintaro Nishimura Akira Tsuji 《Journal of nuclear medicine》2008,49(4):615-622
H+/peptide transporter, PEPT1, is functionally expressed in some human cancer cell lines and might be a candidate molecular target for detection of cancers in vivo using PET. The aim of the present study was to establish a novel tumor-imaging technology using a PET tracer targeted to H+/peptide transporter(s). We also compared the tracer with 18F-FDG, focusing on the specificity of their accumulation between tumor and inflammatory tissues. METHODS: A dipeptide PET tracer, 11C-glycylsarcosine (11C-Gly-Sar), was injected intravenously into athymic mice transplanted with human pancreatic, prostate, and gastric cancer cells. The distribution patterns of 11C-Gly-Sar and 18F-FDG in the tumor-bearing mice, and in mice with inflammatory tissue, were assessed by imaging with a positron planar imaging system (PPIS). Tissue distributions of tracer radioactivity were also measured. The expression levels of PEPT1 and PEPT2 (PEPTs) proteins in tumor xenografts and inflammatory tissue were examined by immunohistochemical analysis. The messenger RNA expression levels of PEPTs in 58 available cancer cell lines were quantified by means of real-time polymerase chain reaction. RESULTS: All 3 tumor xenografts were well visualized with the PPIS after injection of 11C-Gly-Sar. Expression of PEPTs in those xenografts was confirmed by immunohistochemical analysis. Tumor-to-blood concentration ratios of 11C-Gly-Sar increased in a time-dependent manner and were much higher than unity. Most of the radioactivity found in the tumor tissue was recovered as the intact tracer. These results indicated that 11C-Gly-Sar was taken up by the PEPTs in tumor xenografts. It is noteworthy that 11C-Gly-Sar was minimally present in inflammatory tissues that expressed no PEPT1 or PEPT2 protein, whereas 18F-FDG was highly accumulated, with the values of the selectivity index being >25.1 and 0.72 for 11C-Gly-Sar and 18F-FDG, respectively. The mRNAs of PEPT1 and PEPT2 were expressed in 27.6% and 93.1%, respectively, of the cancer cell lines examined in the present study. CONCLUSION: The present study indicates that 11C-Gly-Sar is a promising tumor-imaging agent and is superior to 18F-FDG for distinguishing between tumors and inflammatory tissue. Because PEPTs were ubiquitously expressed in various types of tumor cells examined, 11C-Gly-Sar could be useful for the detection of many types of cancers. 相似文献
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35.
Ung-il Chung Hiroshi Kawaguchi Tsuyoshi Takato Kozo Nakamura 《Journal of orthopaedic science》2004,9(4):410-414
Mammalian bones have three distinct origins (paraxial mesoderm, lateral plate mesoderm, and neural crest) and undergo two different modes of formation (intra-membranous and endochondral). Bones derived from the paraxial mesoderm and lateral plate mesoderm mainly form through the endochondral process. During this process, hypertrophic chondrocytes play a vital role in inducing both osteogenesis and angiogenesis. One of the essential osteogenic factors secreted from hypertrophic chondrocytes is Indian hedgehog (Ihh). In contrast, bones derived from the neural crest mainly form through the intramembranous pro-cess and do not require Ihh. Thus, depending on their origin, bones have distinct signaling properties, which need to be considered in the research and application of bone biology.Presented at the 18th Annual Research Meeting of the Japanese Orthopaedic Association, Kitakyushu, Japan, October 17, 2003 相似文献
36.
37.
M Okada S Matsuda S Kozawa S Yasuoka K Ogawa K Nakamura 《Japanese circulation journal》1986,50(9):888-894
Between 1970 and 1985, 221 patients with coronary artery occlusive disease underwent aorto-coronary bypass (A-C bypass) and other procedures. Among these patients, 187 had A-C bypass alone and A-C bypass in addition to correction of valvular lesions or arterialization of the coronary vein, myocardial puncture by laser. The remaining 34 had surgical corrections for myocardial infarction and its complications. Subjects were 100 patients who underwent A-C bypass alone over 6 months ago and whose follow-up study could be performed in 93 survival cases [corrected]. Subsequently, 94% of the patients have met the criteria for grade I of NYHA functional capacity and have returned to normal work at a mean of 4 years and 2 months after surgery. Improved left ventricular function has been maintained postoperatively in the patients with complete revascularization. Improved operative technique, in addition to intraoperative balloon angioplasty and onlay patch grafting, have increased the patency rate (78% in 1 mm, 94% in 2 mm of coronary diameter) of the grafts with postoperative anticoagulant therapy. On the basis of our long-term observations, coronary bypass surgery, particularly in complete revascularization, provides for significant improvement in both the quality and life expectancy of patients with severe coronary heart disease. Treadmill exercise test and magnetic resonance image (MRI) were useful, non-invasive and acceptable examinations in long-term follow up. 相似文献
38.
Benign schwannoma of the pancreas 总被引:2,自引:0,他引:2
Labile Togba Soumaoro Kenichi Teramoto Tohru Kawamura Noriaki Nakamura Takahiro Sanada Kenichi Sugihara Shigeki Arii 《Journal of gastrointestinal surgery》2005,9(2):288-290
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were
diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma
occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic
masses is briefly discussed. 相似文献
39.
40.
Kazuaki Shimamoto Toru Kita Hiroshi Mabuchi Masunori Matsuzaki Yuji Matsuzawa Noriaki Nakaya Shinichi Oikawa Yasushi Saito Jun Sasaki Hiroshige Itakura 《Hypertension research》2007,30(2):119-123
Hyperlipidemia, hypertension, and diabetes mellitus (DM) are well-established risk factors for cardiovascular disease. We analyzed the cardiovascular events in hyperlipidemic patients with or without DM who were administered open-labeled simvastatin in groups stratified by blood pressure level using data from the Japan Lipid Intervention Trial (J-LIT). Hyperlipidemic patients with DM (n=6,288) had significantly more cardiovascular events than those without DM (n=33,933). The incidence rates of total cardiovascular events in the Non-DM and DM groups were 15.40 and 25.76 per 1,000 patients for the 6-year period, respectively. The relative risk of total cardiovascular events in the DM vs. the Non-DM group was 1.68, and the relative risk was significantly higher in the DM than in the Non-DM group. The relative risks of total cardiovascular events were significantly higher in DM and Non-DM patients whose systolic blood pressure (SBP) was greater than or equal to 130 mmHg compared to that of Non-DM patients whose SBP was less than 130 mmHg, and in DM and Non-DM patients whose diastolic blood pressure (DBP) was greater than or equal to 80 mmHg compared to that of Non-DM patients whose DBP was less than 80 mmHg. In all groups stratified by SBP and DBP, relative risks of total cardiovascular events were higher in DM patients than in Non-DM patients. For patients with hypercholesterolemia and DM, blood pressure should be strictly controlled in order to prevent both coronary events and stroke. These results are in good agreement with the JNC 7 and the ESH/ESC guidelines for DM patients, which recommended that the SBP and DBP be less than 130 and 80 mmHg, respectively. 相似文献