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21.
This is the first report of a patient with venous insufficiency following compressive arachnoiditis ossificans (AO). Symptoms of fluctuating monoplegia and sensory disturbance appeared monthly, lasting several weeks each time. Spinal magnetic resonance imaging (MRI) showed high T2-weighted signal intensity in the posterior portion of the column from T11 to T12 and an intradural lesion with low T2-weighted signal intensity. Neurological function and MRI improved markedly following an operation on AO. The symptoms seen in the present case were due to posterior venous insufficiency following compressive AO.  相似文献   
22.
The effect of sodium thiosulfate (STS) on the pharmacokinetics and ototoxicity of cisplatin (CDDP) was investigated in guinea pigs. Animals received three intramuscular injections of 7.5 mg/kg CDDP separated by intervals of 5 days with or without STS (1,000 mg/kg) administered intraperitoneally immediately and 1 h after each injection of CDDP or 3 and 6 h later. When administered alone, CDDP caused total outer hair cell (OHC) loss in the basal and second turns of the cochlea. In the group administered CDDP and STS, damage to the OHCs was mild when STS was given concurrently, but was severe when STS was given 3 and 6 h later. Pharmacokinetics measured as free and total platinum (Pt) concentrations in plasma and total Pt concentration in perilymph was not affected after administration of STS with CDDP. These results suggest that an inactive Pt-thiosulfate complex is formed in plasma and is measured as a free Pt component which enters the perilymph via the blood-cochlear barrier. Two possible mechanisms are proposed by which STS reduces ototoxicity: entry of CDDP into target cells such as OHCs and striai marginal cells or binding to intracellular macromolecules of these cells is prevented.  相似文献   
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In yeast, an endoplasmic reticulum (ER)-associated protein, Ire1p, is believed to initiate the unfolded protein response (UPR), that is responsible for protein folding in the ER under stressed conditions. Two mammalian homologs of Ire1p have been identified, Ire1 alpha and Ire1 beta. We have previously reported that familial Alzheimer's disease linked presenilin-1 variants downregulate the signaling pathway of the UPR by affecting the phosphorylation of Ire1 alpha. In the present study, we cloned the mouse homolog of Ire1 alpha for generating genetically modified mice. Ire1 alpha was ubiquitously expressed in all mouse tissues examined, and was expressed preferentially in neuronal cells in mouse brain. This led us to investigate the effects of the downregulation of the UPR on the survival of neuronal cells under conditions of ER stress. Morphological and biochemical studies using a dominant-negative form of mouse Ire1 alpha have revealed that cell death caused by ER stress can be attributed to apoptosis, and that the downregulation of the UPR enhances the apoptotic process in the mouse neuroblastoma cell line, Neuro2a. Our results indicate that genetically modified mice such as transgenic mice with a dominant-negative form of Ire1 alpha might provide further understanding of the pathogenic mechanisms of Alzheimer's disease and other neurodegenerative disorders.  相似文献   
25.
The outcomes of three methods of intensity-modulated radiation therapy (IMRT) for localized prostate cancer were evaluated. Between 2010 and 2018, 308 D’Amico intermediate- or high-risk patients were treated with 2.2 Gy daily fractions to a total dose of 74.8 Gy in combination with hormonal therapy. Overall, 165 patients were treated with 5-field IMRT using a sliding window technique, 66 were then treated with helical tomotherapy and 77 were treated with volumetric modulated arc therapy (VMAT). The median age of patients was 71 years. The median follow-up period was 75 months. Five-year overall survival (OS) and biochemical or clinical failure-free survival (FFS) rates were 95.5 and 91.6% in the 5-field IMRT group, 95.1 and 90.3% in the tomotherapy group and 93.0 and 88.6% in the VMAT group, respectively, with no significant differences among the three groups. The 5-year cumulative incidence of late grade ≥2 genitourinary and gastrointestinal toxicities were 7.3 and 6.2%, respectively, for all patients. Late grade ≥2 gastrointestinal toxicities were less frequent in patients undergoing VMAT (0%) than in patients undergoing 5-field IMRT (7.3%) and those undergoing tomotherapy (11%) (P = 0.025), and this finding appeared to be correlated with the better rectal DVH parameters in patients undergoing VMAT. Other toxicities did not differ significantly among the three groups, although bladder dose-volume parameters were slightly worse in the tomotherapy group than in the other groups. Despite differences in the IMRT delivery methods, X-ray energies and daily registration methods, all modalities may be used as IMRT for localized prostate cancer.  相似文献   
26.
Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm2) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10–3 mm2/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA.  相似文献   
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BACKGROUND: The purpose of this study is to evaluate the efficacy of postoperative adjuvant chemotherapy using uracil and tegafur (UFT) for colorectal cancer. METHODS: In a multicenter trial among 43 institutions for patients who underwent curative resection of Dukes' B or C colorectal cancer, a surgery alone group (control group) and a treatment group (UFT group) to which UFT was administered at 400 mg/day for 2 years following surgery were compared. A total of 320 patients were registered between March 1991 and April 1994, and 289 of these patients were analyzed as a full-analysis set. RESULTS: The 5-year disease-free survival rate was 75.7% in the UFT group and 60.1% in the control group, respectively, and the stratified log-rank test showed the statistical significance ( P=0.0081). This difference was marked in rectal cancer ( P=0.0016) and, in particular, the local recurrence was reduced. No significant difference was observed in the 5-year survival rate. The incidence of adverse reactions on administration of UFT was low, and there was no serious adverse reaction. CONCLUSION: It is suggested that the consecutive administration of UFT at 400 mg/day was an effective and highly safe therapeutic method as postoperative adjuvant chemotherapy for rectal cancer.  相似文献   
29.
Purpose Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical significance of Aurora-A status. Experimental Design A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical staining was used to detect Aurora-A expression. Results Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7, and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%, and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A expression was an independent and significant factor to predict a poor prognosis. Conclusions Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative activity in NSCLC.  相似文献   
30.
We report a case of symptomatic subacute in-stent thrombosis after carotid artery angioplasty and stenting (CAS). The patient was a 72-year-old man who had severe asymptomatic right carotid artery stenosis. He received CAS with distal protection, and gained 100% opening of the right carotid artery. The administration of dual antiplatelet therapy (Aspirin 100 mg/day+Cilostazol 100 mg/day), which had been given since two weeks before the procedure, was continued afterwords. On the seventh day after the stent placement, the patient showed sudden onset of left hemiparesis and conjugated deviation of both eyes to the right side and followed by falling into a comatose state. Emergency angiography showed near occlusion of the right carotid artery, suggesting subacute in-stent thrombosis. In conjunction with the intravenous administration of tissue plasminogen activator (1300,000 IU), we performed additional stent placement on the stented portion of the ICA and gained full recanalization of the ICA about three hours after the onset of the symptoms. The patient showed rapid recovery and returned home with slight clumsiness of his right hand. Symptomatic subacute in-stent thrombosis after CAS is a rather rare complication. We discuss on the possible cause of this and stress the necessity of an additional emergency stenting to gain rapid recanalization.  相似文献   
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