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51.
Kenji Nakashima M.D. Kazuro Takahashi M.D. 《Psychiatry and clinical neurosciences》1988,42(2):297-306
Abstract: The distribution of somatosensory evoked potentials (SEPs) after stimulation of the median nerve at the wrist was examined in 10 normal subjects using isopotential maps. The latencies of continuous negative and positive peaks were measured in each lead. The differences of the potentials at these latencies were measured in all the leads and the isopotential maps were constructed. The distribution of P0–NI was all similar. The latencies of P0 were almost the same in all the leads at about 13 msec. The distribution of NI-PI-NII was divided into three types—N16–P20–N28 localized in the frontal region, N17–P22–N30 localized in the central region and N19–P25–N33 distributed in the parieto-occipito-temporal regions. The distributions of NII-PII and PII-NIII were all similar, with high amplitudes in the central region. The latencies of PII and NIII were almost the same in all the leads at about 45 msec and 68 msec. 相似文献
52.
Kimiyoshi Ozawa Kenji Hashimoto Takashi Kishimoto Eiji Shimizu Hiroshi Ishikura Masaomi Iyo 《Neuropsychopharmacology》2006,59(6):546-554
BACKGROUND: Maternal viral infection is associated with increased risk for schizophrenia. It is hypothesized that the maternal immune response to viruses may influence fetal brain development and lead to schizophrenia. METHODS: To mimic a viral infection, the synthetic double strand RNA polyriboinosinic-polyribocytidilic acid (poly I:C) was administered into pregnant mice. Behavioral evaluations (thigmotaxis, methamphetamine [MAP]-induced hyperactivity, novel-object recognition test [NORT]), sensorimotor gating (prepulse inhibition [PPI]), and biochemical evaluation of the dopaminergic function of the offspring of phosphate-buffered saline (PBS)-treated dams (PBS-mice) and that of poly I:C-treated dams (poly I:C-mice) were examined. RESULTS: In juveniles, no difference was found between the poly I:C-mice and PBS-mice. However, in adults, the poly I:C-mice exhibited attenuated thigmotaxis, greater response in MAP-induced (2 mg/kg) hyperlocomotion, deficits in PPI, and cognitive impairment in NORT compared with the PBS-mice. Cognitive impairment in the adult poly I:C-mice could be improved by subchronic administration of clozapine (5.0 mg/kg) but not haloperidol (.1 mg/kg). Increased dopamine (DA) turnover and decreased receptor binding of D2-like receptors, but not D1-like receptors, in the striatum were found in adult poly I:C-mice. CONCLUSIONS: Prenatal poly I:C administration causes maturation-dependent increased subcortical DA function and cognitive impairment in the offspring, indicating a neurodevelopmental animal model of schizophrenia. 相似文献
53.
Jiro Okochi Kenji Toba Tai Takahashi Kozo Matsubayashi Masanori Nishinaga Ryutaro Takahashi Takashi Ohrui 《Geriatrics & Gerontology International》2006,6(4):223-227
Background: The aim of this study is to construct a simple screening test for the risk of falls in community-dwelling elder persons.
Methods: A total of 1378 community-dwelling people aged 65 years and older in five different communities in Japan were asked to answer a self rated questionnaire including 22 items covering physical, cognitive, emotional and social aspects of functioning and environmental factors. At a six-month follow-up, the outcome of fall occurrence and the number of falls was ascertained by social workers, health visitors or nurses.
Results: Five out of 22 items were selected using a logistic regression model. Using this five-item version, a screening test was constructed, and at the best cut-off point, the sensitivity and specificity were 68% and 70%, respectively. The validity of this scale was tested on persons with cognitive dysfunction.
Conclusion: The simplicity and the predictive validity of the screening test support the use of this test in health check ups or general outpatient facilities. 相似文献
Methods: A total of 1378 community-dwelling people aged 65 years and older in five different communities in Japan were asked to answer a self rated questionnaire including 22 items covering physical, cognitive, emotional and social aspects of functioning and environmental factors. At a six-month follow-up, the outcome of fall occurrence and the number of falls was ascertained by social workers, health visitors or nurses.
Results: Five out of 22 items were selected using a logistic regression model. Using this five-item version, a screening test was constructed, and at the best cut-off point, the sensitivity and specificity were 68% and 70%, respectively. The validity of this scale was tested on persons with cognitive dysfunction.
Conclusion: The simplicity and the predictive validity of the screening test support the use of this test in health check ups or general outpatient facilities. 相似文献
54.
Koichi Tanaka Kazue Ozawa Satoshi Teramukai Yasutsugu Takada Hiroto Egawa Satoshi Kaihara Yasuhiro Fujimoto Yasuhiro Ogura Mureo Kasahara Masako Ono Hiroshi Sato Kenji Takai Masanori Fukushima Nagahiro Minato 《Liver transplantation》2006,12(5):792-800
The primed status of T cells is markedly different among liver transplant recipients, due to a lifetime of antigen exposure and reduced thymopoiesis by aging, and diseases. This study aims to characterize the preoperative immunological status of CD8+ T cell subpopulations and relate it to the outcome for liver transplant recipients. We classified 112 liver transplant recipients into 5 groups, based on hierarchical clustering of the CD8+CD45 isoform proportion of T cells. In Groups I and II (pediatric), the naive T cell proportion was more than 50%. In adult recipients, Group III was characterized by a naive T cell proportion of 50%, Group IV had the greatest effector/memory T cells (EM), and Group V had the greatest proportion of effector T cells. In Groups IV and V, the effector T cell proportion was considerably higher, and was accompanied by marked downregulation of the CD27+CD28+ subsets and upregulation of interferon gamma (IFN)-gamma, tumor necrosis factor-alpha, and perforin expression. Group V recipients tended to be complicated postoperatively, with a significantly reduced survival rate (1 yr, 66.8%) and markedly reduced Eastern Cooperative Oncology Group performance status. 相似文献
55.
Shinji Homma Kenji Satoh Hitoshi Matsuo Minoru Yagi Jun Hasegawa Tomoyuki Maruta Naozumi Watanabe Tsuneo Iiai Katsuyoshi Hatakeyama 《Journal of Smooth Muscle Research》2004,40(6):271-280
Electrogastrograms (EGGs) were recorded in patients both before and after receiving proximal gastrectomy plus jejunal interposition (PGJI) or just after receiving total gastrectomy plus jejunal interposition (TGJI). Intraluminal pressure was also recorded in some postoperative patients. The EGG 3 cpm component (2.5-4.9 cpm) remained after PGJI, but subsequently decreased with a significant reduction in the preoperative to postoperative ratio of the 3 cpm components (P<0.05). The mean frequency of the 3 cpm components increased significantly after PGJI (P<0.05) and its instability factor increased. The EGG 10 cpm components became relatively dominant compared to other frequency components in 2 out of 8 of patients having PGJI but the mean amplitude of 10 cpm decreased. In TGJI patients, only the 10 cpm component was conspicuous in EGG as in the case of total gastrectomy and Roux en Y anastomosis procedures. The spectral frequencies of intraluminal pressure in the interposed jejunum were similar to the EGG of 10 cpm components both in the case of PGJI and TGJI patients. In conclusion, surface EGG could record the electrical activities of the interposed jejunum more easily in patients having had TGJI than in PGJI. 相似文献
56.
Kenji Kihara Shinichi Ueno Masahiko Sakoda Takashi Aikou 《Liver transplantation》2005,11(12):1574-1580
Recent studies have shown that hyperbaric oxygen therapy (HBOT) reduces neutrophil endothelial adherence in venules and also blocks the progressive arteriolar vasoconstriction associated with ischemia-reperfusion (I-R) injury in the extremities and the brain. In order to elucidate the effects of HBOT after I-R in digestive organs, particularly in the liver, we evaluated the following: 1) the relationship between timing of HBOT and tissue damage; and 2) HBOT's effects on neutrophil sequestration. Using a hepatic I-R (45 minute) model in male rats, survival rate, liver tissue damage, and neutrophil accumulation within the sinusoids in the HBOT-treated group (Group H) were compared to those in the nontreated group (Group C). For the HBOT-treated group, HBOT was administered as 100% oxygen, at 2.5 atm absolute, for 60 minutes. When HBOT was given 30 minute after I-R, the survival rate was much better in Group H than in Group C. HBOT performed within 3 hours of I-R markedly suppressed increases in the malondialdehyde level in tissues of the liver and lessened the congestion in the sinusoids. In addition, HBOT just after I-R caused decreased number of cells stained by the naphthol AS-D chloroacetate esterase infiltrating into the sinusoids. HBOT 3 hours after reperfusion, however, showed no clear effects upon neutrophil sequestration compared to Group C. These results indicate that HBOT performed within 3 hours of I-R alleviates hepatic dysfunction and improves the survival rate after I-R. Herein, we propose 1 possible mechanism for these beneficial effects: early HBOT given before neutrophil-mediated injury phase may suppress the accumulation of neutrophils after I-R. In conclusion, we believe that the present study should lead to an improved understanding of HBOT's potential role in hepatic surgery. 相似文献
57.
58.
Hisayoshi Oka Masayuki Yoshioka Kenji Onouchi Masayo Morita Soichiro Mochio Masahiko Suzuki Toshiaki Hirai Mitsuyoshi Urashima Kiyoharu Inoue 《Movement disorders》2007,22(10):1510-1514
We assessed the relations of visual hallucinations (VH) to cardiovascular autonomic dysfunction in patients with Parkinson's disease (PD). The subjects were 37 patients without VH (VH(-)) and 31 with VH (VH(+)). Autonomic function was evaluated on the basis of cardiac 123-radioiodinated metaiodobenzylguanidine (123I-MIBG) uptake and hemodynamic testing with Valsalva maneuver. Systolic blood pressure (SBP) and plasma norepinephrine concentrations (NE) were measured by tilt-table testing. 123I-MIBG uptake was lower in VH(+) than VH(-). Hemodynamic studies showed that VH(-) had only cardiac sympathetic and parasympathetic dysfunction, while VH(+) additionally had reduced vasomotor sympathetic functions. The fall in SBP during tilt-table testing was greater in VH(+) than VH(-). NE and its difference in the supine and upright positions were decreased in VH(+). We conclude that cardiac and vasomotor sympathetic dysfunction is more severe in VH(+) than in VH(-). Severe dysfunction in PD with VH is probably attributed to Lewy-body lesions or neuronal loss in sympathetic ganglia, the central autonomic system, or both. 相似文献
59.
Keiko Imamura Kenji Wada Kenichi Yasui Kazuhiro Nakaso Yasuhiro Watanabe Hisanori Kowa Kenji Nakashima 《Clinical neurology》2004,44(7):446-449
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors. 相似文献
60.
Kenji Yamao Atsushi Irisawa Hiroyuki Inoue Koji Matsuda Mitsuhiro Kida Shomei Ryozawa Yoshiki Hirooka Teruo Kozu 《Digestive endoscopy》2007,19(Z1):S180-S205
Standard imaging techniques using a curved linear array echoendocope are summarized to facilitate the attainment of expertise in endoscopic ultrasonography and endoscopic ultrasound‐guided fine needle aspiration, and to promote the widespread use of this diagnostic and therapeutic tool. Typical images of the mediastinal organs, the bilio‐pancreatic systems and neighboring organs by scanning from the esophagus, stomach, duodenal bulb, and descending portion of the duodenum, are shown in a sequential manner. The basic techniques of endoscopic ultrasound‐guided fine needle aspiration are also presented. 相似文献