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11.
Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.  相似文献   
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We report a case of bilateral internal carotid artery (ICA) stenosis treated with stenting. A 78-year-old man suffered from vascular dementia and left hemiparesis, and, by magnetic resonance angiogram (MRA), was diagnosed as having bilateral ICA stenosis. Cerebral angiogram showed severe, bilateral ICA stenosis (right; 88%, left; 93%) and xenon single photon emission tomography (SPECT) showed severely decreased cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). We performed bilateral carotid angioplasty with self-expanding stents. Both CBF and CVR were improved bilaterally after the operation. The patient was discharged without neurological deficits. Carotid stenting may be an alternative treatment for severe ischemia caused by severe, bilateral ICA stenosis.  相似文献   
14.
We studied 13 consecutive patients with bone and soft tissue sarcomas of the hand and wrist. Chondrosarcoma, Ewing's sarcoma, synovial sarcoma and epithelioid sarcoma were the most frequent histological diagnoses. Limb-sparing surgery was performed in ten patients but eventually three patients required an amputation. Surgical margins were wide in nine patients and marginal in four. Adjuvant therapy for nine patients consisted of chemotherapy in five and chemotherapy with radiation in four. Local recurrence occurred in two patients with epithelioid sarcoma. There was no significant relationship between surgical margin and local recurrence. Distant metastasis occurred in four patients. The 5-year survival rate was 66%. The mean functional score was 87%. Our study indicates that treatment consisting of resection of these tumours with either a wide margin or a marginal margin followed by adjuvant radiation appeared to be safe and resulted in an acceptable degree of limb function except in the patients with epithelioid sarcoma.  相似文献   
15.
A 72-year-old woman presented with lower urinary tract symptoms (incomplete voiding, voiding pain, and gross hematuria) 2 years after a tension-free vaginal tape (TVT) procedure for stress urinary incontinence. Cystoscopy revealed erosion of the urethra associated with a urethral stone attached to a polypropylene mesh. We performed transurethral resection of the polypropylene mesh and transurethral lithotripsy. After removal of the mesh, she had stress urinary incontinence but her symptoms resolved. Urethral erosion is a rare complication of TVT, and the method of handling the intrusive mesh has not been standardized. Transurethral endoscopic resection of the eroding mesh is a minimally invasive and successful procedure that should be considered for the treatment of this complication resulting from TVT.  相似文献   
16.
A 68-year-old man developed right homonymous hemianopic paracentral scotomas from acute infarction of the left extrastriate area. He was studied over the ensuing 12 months with visual fields, conventional MRI, functional MRI (fMRI), and diffusion tensor imaging (DTI). As the visual field defect became smaller, fMRI demonstrated progressively larger areas of cortical activation. DTI initially showed that the lesioned posterior optic radiations were completely interrupted. This interruption lessened in time and had disappeared by one year after onset. fMRI and DTI are innovative measures to follow functional and structural recovery in the central nervous system. This is the first reported application of these imaging techniques to acute cerebral visual field disorders.  相似文献   
17.
The details are reported of bladder dysfunction in a Japanese boy with adrenoleukodystrophy. He developed gait disturbance at the age of 15 years. Spastic paraparesis progressed from the legs to the hands and brain magnetic resonance imaging showed characteristic degenerative change. Detrusor hyperreflexia was found by a urodynamic study and detrusor-sphincter dyssynergia was also suspected.  相似文献   
18.
The authors report on a 51-year-old woman with a 9-year history of rheumatoid arthritis (RA) who presented with symptomatic rheumatoid nodules in the lumbar extradural region with compression on the L-5 nerve roots bilaterally. She had also suffered from dysesthesia in the right lower leg and intermittent claudication. Magnetic resonance imaging revealed masses compressing the dural sac, and on lumbar myelography and computed tomography myelography a filling defect at L4-5 was revealed, which was compressing the dural sac posterolaterally on both sides. The masses were surgically removed. On histological examination the typical characteristics of rheumatoid nodules were found. Soon after the operation all of the patient's symptoms disappeared. There have been few reports on extradural rheumatoid nodules. Patients with RA usually complain of articular symptoms, and in fact the patient in the present study had been referred to the authors' institution for total hip arthroplasty. However, various symptoms other than those arising from articular lesions were found clinically. The authors believe that if patients with RA are also examined for extraarticular lesions, it is likely that these will be more frequently detected.  相似文献   
19.
BACKGROUND: Myeloablative cord blood transplantation (CBT) for adult patients offers a 90% chance of engraftment with a 50% rate of transplant-related mortality, mostly attributable to infection. We have demonstrated the feasibility of reduced-intensity CBT (RI-CBT) for adult patients, in which cyclosporine was used for acute graft-versus-host disease (GVHD) prophylaxis. Transplantation-related mortality (TRM) was 27% within 100 days. Therefore our objective was to evaluate the feasibility of RI-CBT with tacrolimus as GVHD prophylaxis for adult patients with hematologic malignancies. METHODS: Thirty-four patients with a median age of 56.5 years (range; 22-68) with hematologic diseases underwent RI-CBT at Toranomon Hospital between November 2003 and September 2004. Preparative regimen comprised fludarabine 25 mg/m2 on days -7 to -3, melphalan 80 mg/m2 on day -2, and 4 Gy total body irradiation on day -1. GVHD prophylaxis was continuous intravenous infusion of tacrolimus 0.03 mg/kg, starting on day -1. RESULTS: Thirty-one patients achieved neutrophil engraftment at a median of day 20. Median infused total cell dose was 2.4 x 10E7/kg (range; 1.6-4.8). Thirty-two patients achieved complete donor chimerism at day 60. Grade II-IV acute GVHD occurred in 45% of patients, with a median onset of day 26. Primary disease recurred in five patients, and TRM within 100 days was 12%. Estimated 1-year overall survival was 70%. CONCLUSION: This study demonstrated the possible improvement in transplant-related mortality by tacrolimus as GVHD prophylaxis in adult RI-CBT recipients.  相似文献   
20.
We herein describe a 60-year-old Japanese man with a giant retroperitoneal liposarcoma undergoing leiomyosarcomatous differentiation. He was admitted to our hospital because of a 5-month history of dysphagia and abdominal distention. Abdominal computed tomography showed a giant tumor that occupied the entire retroperitoneal space. The majority of the mass was lipomatous and low density; both a heterogenous and solid mass were also present. A giant retroperitoneal liposarcoma was diagnosed, and tumor resection was performed. At surgery, the tumor was mostly isolated from the retroperitoneum and other organs. Histopathologically, the tumor comprised well-differentiated and dedifferentiated liposarcoma with heterologous differentiation of the leiomyosarcomatous components, which is a rare phenomenon in liposarcoma. The patient was alive 3 years after the first treatment, although he has had 3 local recurrences (approximately one recurrence yearly) and has been treated by repeated resection and radiotherapy.Key words: Retroperitoneum, Liposarcoma, Leiomyosarcomatous differentiationDedifferentiated liposarcoma (DL) is one of the most frequent sarcomas of the retroperitoneum. It is defined by the association of an atypical lipomatous tumor, namely, areas of well-differentiated liposarcoma (WDL), with a dedifferentiated component. WDL is composed of mature adipocytes and atypical stromal cells with an enlarged, hyperchromatic nucleus. Usually, the dedifferentiated part of the liposarcoma is composed of either a spindle/pleomorphic high-grade sarcoma or a mixoid/spindle cell low-grade sarcoma. The WDL component may be easily overlooked, and DL may thus be mistaken for another high-grade sarcoma. It has been reported in one study that approximately 5% of the dedifferentiated component showed heterologous differentiation, such as leiomyosarcoma, rhabdomyosarcoma, osteosarcoma, and angiosarcoma.1 A less common phenomenon is the occurrence of WDL with leiomyosarcomatous (LMS) differentiation.2 Limited to the retroperitoneum, only 8 cases of liposarcoma with LMS components have been reported.37 We herein report a case of retroperitoneal liposarcoma comprising WDL and DL, with LMS components, treated by surgical resection.  相似文献   
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