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AimTo elucidate the morphological characteristics of spike-wave complexes (SWCs) causing myoclonic seizures (MS) in childhood-onset idiopathic myoclonic epilepsies.Subjects and MethodsThe subjects were 8 patients, including 4 with epilepsy with myoclonic-atonic seizures (EMAS), 3 with myoclonic epilepsy in infancy (MEI) and 1 with idiopathic unclassifiable myoclonic epilepsy. Morphometric parameters of the SWCs were compared between those with MS [SWC-MS (+)] and those without MS [SWC-MS (-)], and a correlation coefficient analysis was performed between the SWC parameters and the duration of myoclonic electromyogram (EMG) potentials.ResultsA total of 155 SWC-MS (+) (range: 7 ~ 34) and 80 SWC-MS (-) (10 each as a control) were analyzed. Comparison of the parameters of the SWCs between SWC-MS (+) and SWC-MS (-) demonstrated that the depth and the width of the positive-sharp-components (PSC) in the SWC-MS (+) were significantly deeper in amplitude and longer in duration than those in the SWC-MS (-), respectively, in all 8 patients (P < 0.05), whereas the number of the polyphasic-multiple-spike-components (PMSC) and the height of negative-spike-components (NSC) were not significantly different in most of the patients, respectively. The depth and the width of PSC were also significantly correlated with the duration of myoclonic EMG potentials in all patients except one [depth of PSC (n = 7): r = 0.623 ~ 0.888; width of PSC (n = 8): r = 0.676 ~ 0.948, P < 0.05].ConclusionsThis study revealed that the depth and width of PSC of the SWC are positively correlated with the MS intensity in childhood-onset idiopathic myoclonic epilepsies and are an important neurophysiological marker to generate MS.  相似文献   
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Intracellular structures of HeLa cells are observed using a direct electron beam excitation-assisted fluorescence (D-EXA) microscope. In this microscope, a silicon nitride membrane is used as a culture plate, which typically has a low biocompatibility between the sample and the silicon nitride surface to prevent the HeLa cells from adhering strongly to the surface. In this work, the surface of silicon nitride is modified to allow strong cell attachment, which enables high-resolution observation of intracellular structures and an increased signal-to-noise ratio. In addition, the penetration depth of the electron beam is evaluated using Monte Carlo simulations. We can conclude from the results of the observations and simulations that the surface modification technique is promising for the observation of intracellular structures using the D-EXA microscope.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0180) Microscopy  相似文献   
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A 73-year-old Japanese woman was referred for examination of right flank pain and progressive hypertension. Abdominal CT incidentally detected a right adrenal mass 8 cm in size. The tumor exhibited isodensity by CT and contained high-intense lesion by T2-weighted MRI. Scintigraphy with (131) I-metaiodobenzylguanidine and (131) I-adosterol showed no abnormal uptake by whole body scan. Positron emission tomography scan with (18) F-2-fluoro-D-deoxyglucose demonstrated an exclusive uptake in the right adrenal mass. Adrenocortical hormone levels and catecholamine secretion were within normal range; however, the level of serum neuron-specific enolase (NSE) was found to be markedly high. After controlling systemic blood pressure with an alpha1-blocker, the right adrenal tumor was surgically removed, along with the right kidney and inferior vena cava which adhered to it. The tumor was pathologically proven to be leiomyosarcoma, which was immunohistochemically positive with alpha-smooth muscle actin and negative with CD57, S-100 and c-kit proteins. Notably, NSE protein was massively expressed in the resected tumor. After surgery blood pressure was controlled with regular medication and serum NSE levels have since normalized. The possibility of leiomyosarcoma should be kept in mind in adrenal incidentalomas with rapid growth and atypical radiological images. Our findings suggest that circulating NSE levels may be clinically useful for early detection of recurrence.  相似文献   
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Background/Aims: To investigate differences in clinicopathological features between proximal and distal pT3 colon cancers and to determine whether the depth of the cancer invasion beyond the muscularis propria (DBM) serves as an objective indicator of the depth of tumor invasion in proximal colon cancer and in distal colon cancer. Methodology: A total of 207 patients who underwent surgery for proximal and distal pT3 colon cancer between 1996 and 2001 were included in the analysis. Results: No differences were noted between proximal and distal cancers in lymph node metastasis, distant metastasis, lymphatic/venous invasion, histological type and curability of surgical resection, although proximal cancer patients were significantly older. High-grade malignancy appeared to be more commonly noted in the proximal colon cancer cases but there was no significant difference in prognosis between proximal and distal cancer patients. Conclusions: Regarding the correlation between DBM and prognosis, there was a significant decrease in the 5-year survival rate in patients with proximal lesions of DBM 3000μm or more, and patients with distal lesions of DBM 5000μm or more. DBM is thus an objective indicator of depth of tumor invasion for both proximal and distal lesions, a prognostic factor and a guide to determining whether postoperative adjuvant chemotherapy is indicated for pT3 colon cancer cases.  相似文献   
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