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A patient with posthypoxic cortical action myoclonus was studied using polygraphic EEG-EMG recording techniques and transcranial magnetic stimulation. The myoclonic jerks were not stimulus-sensitive, and were not associated with enhancement of the somatosensory evoked potential (SEP). The most prominent electrophysiological finding was that rhythmic EMG activity was produced when the patient attempted rapid voluntary movement. EEG-EMG polygraph indicated that the rhythmic EMG activity was preceded by rhythmic activity in the EEG recorded overlying the contralateral central region. The frequency of both EEG and EMG activity was the same (approximately 50 Hz). Treatment using a combination of clonazepam, carbamazepine and primidone diminished the action myoclonus, concomitant with the disappearance of the rhythmic EEG and EMG activity. In the sensorimotor cortex of the normal monkey and humans, oscillatory activity ranging between 20-50 Hz has been recorded in the local field potential. Our findings suggest that cortical hyperoscillation may produce this characteristic rhythmic EEG and EMG activity and may, in turn, be related to cortical action myoclonus.  相似文献   
63.
BACKGROUND: The aim of this study was to examine the 1-year cumulative mortality rate and cause of death, and to identify the predictive factors for death after hospital discharge following ischemic stroke and transient ischemic attack (TIA) using data from the Japan Multicenter Stroke Investigators' Collaboration study. METHODS: We prospectively registered 16,922 consecutive patients with acute ischemic stroke or TIA from May 1999 to April 2000 in 156 Japanese hospitals. We mailed a questionnaire to the 15,322 patients who were alive at hospital discharge. RESULTS: 10,981 patients (6,945 men, 4,036 women, age 70 +/- 11 years, median 71, range 19-100 years) were enrolled in the follow-up study. The mean follow-up period was 271 +/- 110 days (median 272 days; range 1-487 days). The 1-year cumulative mortality was 6.8% (7.0% for 10,234 stroke patients and 3.5% for 747 TIA patients). The causes of death were: cerebrovascular disease, 24.1%; pneumonia, 22.6%; heart disease, 18.1%; cancer, 11.0%, and miscellaneous causes, 24.1%. Multivariate analysis suggested that male gender, age, diabetes mellitus, atrial fibrillation, history of stroke, nonlacunar stroke, functional disability and transfer to another hospital or nursing home on discharge were significant independent predictors of death during the follow-up period. CONCLUSIONS: The major causes of death after hospital discharge were found to be cerebrovascular diseases, pneumonia and heart diseases. Thus, in order to improve survival after hospital discharge, in addition to appropriate management of vascular risk factors following stroke, it appears to be important to take measures to prevent pneumonia and to discharge patients to their own home, if possible.  相似文献   
64.
BACKGROUND: Intra-arterial urokinase (IA-UK) thrombolysis is frequently given in Japan to selected patients with acute cerebral artery occlusion. However, it is not clear whether or not IA-UK thrombolysis has an efficacy for acute stroke patients. The purpose of this study was to assess the effects of IA-UK thrombolysis in acute cardioembolic stroke patients, by performing a case-control analysis using data from Japan's Multicenter Stroke Investigator's Collaboration (J-MUSIC). METHODS: 16,922 acute ischemic stroke patients were enrolled into J-MUSIC. From these patients, we selected 91 patients (UK group) who met the following criteria: treatment with IA-UK; 20-75 years of age; cardioembolic stroke; presenting with a carotid stroke; admission within 4.5 h of symptom onset, and a National Institutes of Health Stroke Scale (NIHSS) score of 5-22 points on admission. A control group of 182 patients without IA-UK treatment and matched to the NIHSS score, gender, and age was chosen. We compared the modified Rankin scale (mRS) score at discharge and the mortality between the 2 groups. RESULTS: In both groups, the mean age was 65 +/- 8 years, and the median NIHSS score was 14. The mean interval between symptom onset and UK administration was 3.4 +/- 1.3 h, and the IA-UK dose was 392,000 +/- 200,000 units. The mRS score at discharge was lower in the UK group than in the control group (mean, SD, median; 2.8, 2.9, 2 in UK group vs. 3.3, 1.8, 4, in the control, respectively p = 0.031). A favorable outcome (mRS of 0-2) was more frequently observed in the UK group (50.5%) than in the control group (34.1%, p = 0.0124). No difference in the mortality rate was seen between the UK group (11.0%) and the control group (13.3%). As well, there was no difference in the length of hospital stay between the UK group (46 +/- 41 days, mean +/- SD) and the control group (42 +/- 42 days, mean +/- SD). CONCLUSIONS: IA-UK thrombolytic therapy may improve the outcome in hyperacute cardioembolic stroke patients.  相似文献   
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PURPOSE: To evaluate prospectively the relationship between the arterial collateral system at the hepatic hilum and the blood supply to the hilar bile duct by using computed tomography (CT) and angiography during temporary balloon occlusion of the right or left hepatic artery. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. The study included 13 patients with no lesions at the hepatic hilum (eight men and five women; age range, 41-78 years; mean, 65.8 years). After serial angiographic studies were performed for preoperative evaluation or transcatheter arterial chemoembolization, a 5.5-F catheter with an occlusion balloon was positioned in the right or left hepatic artery. Eleven patients underwent angiography of the left hepatic artery with temporary occlusion of the right hepatic artery, and two patients underwent angiography of the right hepatic artery with temporary occlusion of the left hepatic artery. In addition, 11 patients underwent single-level dynamic CT during hepatic arteriography (CTHA) with temporary occlusion of the right or left hepatic artery. The images from angiography and CTHA were interpreted by two authors who assessed the existence of the arterial communication and its branching points, location, and relationship to the hilar bile duct and caudate lobe. RESULTS: During temporary occlusion of the right or left hepatic artery, the communicating arcade (CA) between the right and left hepatic arteries was immediately evident in all patients. On the left side, the CA originated from the segment IV artery in eight patients (62%) and from the left hepatic artery in five (38%). On the right side, the CA originated from the right anterior hepatic artery in six patients (46%), the right hepatic artery in two (15%), and both arteries in five (38%). The CA was extrahepatically located close to the hilar bile duct and forked into a few branches to the caudate lobe. CONCLUSION: The CA may play an important role not only in the interlobar arterial collateral system but also in the blood supplies to the caudate lobe and hilar bile duct.  相似文献   
67.
PURPOSE: To clarify the appropriate voxel dimensions required for pathologic evaluation of areas with ground-glass opacity on lung high-resolution computed tomography (HRCT). MATERIALS AND METHODS: Synchrotron radiation CT (SRCT) images of autopsied lung speci-mens (n=25) that showed ground-glass opacity on HRCT were reconstructed with 12 different voxel dimensions ranging from 0.006 to 0.6 mm. The specimens were micromorphologically categorized into one of three pathologic groups: alveolar, interstitial, and mixed abnormalities. Each SRCT image was independently diagnosed as one of three pathologic groups by six chest radiologists. The diagnostic accuracy required to estimate the appropriate voxel dimensions was compared among different voxel dimensions by means of the Tukey test. RESULTS: Diagnostic accuracy with voxel dimensions less than or equal to 0.06 mm was significantly higher than that with voxel dimensions of 0.18 mm or more (p<0.01). There was, however, no significance of difference in diagnostic accuracy with voxel dimensions of less than or equal to 0.06 mm. In addition, no significant difference in diagnostic accuracy was found with voxel dimensions of 0.18 mm or more. CONCLUSION: The appropriate voxel dimensions are approximately 0.06 mm for pathologic differentiation of areas with ground-glass opacity on HRCT.  相似文献   
68.
AIM: Human T-lymphotropic virus type-I (HTLV-I) infection occurs via mothers' milk during feeding. However, freeze-thaw processing can eliminate the infectivity of the mother's milk of HTLV-I carriers. METHODS: A long-term follow-up survey was conducted to investigate the HTLV-I infectivity of frozen-thawed mothers' milk among infants whose mothers were HTLV-I seropositive. RESULTS: Infants fed frozen-thawed mothers' milk did not become HTLV-I antibody-positive up until 1 year old, and all children followed up until an age of 11-12 years were antibody negative. CONCLUSIONS: This study showed that freeze-thaw processing can eliminate the HTLV-I infectivity of mothers' milk, and that HTLV-I carriers can indirectly feed their infants using frozen-thawed mothers' milk as a way to prevent HTLV-I infection.  相似文献   
69.
We investigated application of the OS-EM method to the (123)I-IMP ARG method to measure regional cerebral blood flow (rCBF). First, scan time and subsets were fixed at 20 min and 16, respectively, and the influence of iteration on the CCF and quantitative rCBF values obtained by the ARG method was investigated when the iteration number was set at 2, 4, 8, 16, 32, and 90. Next, with the number of iterations set at 4, we compared the scanning times of OS-EM and FBP. We determined that the CCF values remained at the same level irrespective of iteration number. Quantitative rCBF values had no association with iteration number, either. Using the quantitative rCBF values obtained by 20-min. scanning with FBP as a standard, the time period for collecting SPECT data was 10 min, without sacrificing image quality or quantification. Quantitative rCBF obtained by OS-EM was estimated to be higher than that by FBP.  相似文献   
70.
Because of recent progress in imaging modalities, the opportunities to detect pancreatic cystic neoplasms are increasing. However, serous cystadenoma is still uncommon. We report a case of serous cystadenoma treated by laparoscopic distal pancreatectomy. A 52-year-old woman presented with mild upper abdominal pain. Dynamic computed tomography (CT) revealed a solitary cystic lesion 3cm in diameter in the pancreatic tail. Endoscopic ultrasound showed a honeycomb pattern, indicative of serous cystadenoma. To obtain the final diagnosis of the tumor, we performed laparoscopic distal pancreatectomy. A histopathological study showed microcystadenoma with no evidence of malignancy.  相似文献   
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