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991.
Facial nerve palsy: evaluation by contrast-enhanced MR imaging   总被引:4,自引:0,他引:4  
AIM: The purpose of this study was to investigate the value of contrast-enhanced magnetic resonance (MR) imaging in patients with peripheral facial nerve palsy. MATERIALS AND METHODS: MR imaging was performed in 147 patients with facial nerve palsy, using a 1.0 T unit. All of 147 patients were evaluated by contrast-enhanced MR imaging and the pattern of enhancement was compared with that in 300 control subjects evaluated for suspected acoustic neurinoma. RESULTS: The intrameatal and labyrinthine segments of the normal facial nerve did not show enhancement, whereas enhancement of the distal intrameatal segment and the labyrinthine segment was respectively found in 67% and 43% of patients with Bell's palsy. The geniculate ganglion or the tympanic-mastoid segment was enhanced in 21% of normal controls versus 91% of patients with Bell's palsy. Abnormal enhancement of the non-paralyzed facial nerve was found in a patient with bilateral temporal bone fracture. CONCLUSION: Enhancement of the distal intrameatal and labyrinthine segments is specific for facial nerve palsy. Contrast-enhanced MR imaging can reveal inflammatory facial nerve lesions and traumatic nerve injury, including clinically silent damage in trauma.  相似文献   
992.
Deltoid contracture: MR imaging features   总被引:4,自引:0,他引:4  
AIM: To describe the magnetic resonance imaging (MRI) features of deltoid contracture and compare these findings with the operative and histological findings and to determine the utility of MRI for diagnosis and treatment planning. PATIENTS AND METHODS: Retrospective review of clinical and imaging in six patients with deltoid contracture, as well as the operative and histological findings of four operated patients. RESULTS: Magnetic resonance imaging clearly demonstrated the intramuscular fibrous bands of the deltoid as a homogeneously hypointense area with distinctive margins on T1-, T2- and T2*-weighted images. Operative findings were exactly consistent with the findings observed by MRI. CONCLUSION: Deltoid contracture is best evaluated with MRI which facilitates visualization of the intramuscular fibrous bands being pathognomonic of this entity and may provide information useful in treatment planning.  相似文献   
993.
We performed 229 99Tcm-ethyl cysteinate dimer (ECD) single photon emission tomography (SPET) studies in 185 patients with brain tumour. Increased uptake of the tracer was observed in 11 cases. In six of these 11 patients, focal intense activity was seen in the area surrounding the tumour. Five of these six patients had episodes of seizure, and ictal SPET showed further increased uptake in the area of hyperperfusion in one patient. Hyperperfusion surrounding the tumour might be related to seizure. In the remaining five patients, increased accumulation was seen in the tumour. Three of these five patients had a discrepancy between 99Tcm-ECD SPET and 201Tl SPET imaging. There could be some difference in the mechanism of accumulation in the tumour between 99Tcm-ECD and 201Tl.  相似文献   
994.
We reported a 68-year-old female with Creutzfelt-Jakob disease (CJD) presenting hyperparathyroidism. She was suspected as Creutzfelt-Jakob like syndrome at her initial visit to our hospital because of progressive dementia and high level of serum calcium. Finally she was diagnosed as having CJD by the clinical symptoms including progressive dementia and myoclonus and the characteristic patterns of brain CT and electroencephalogram (EEG). CJD presents a variety of symptoms including progressive dementia, apathy and myoclonus. Hyperparathyroidism and toxicity of lithium, delirium and bismuth have been reported to induce similar symptoms of CJD, which are called Creutzfelt-Jakob like syndrome. Therefore, the diagnosis of CJD would be difficult in cases with CJD accompanied with Creutzfelt-Jakob like syndrome. It is rare for otolaryngologists to examine patients with dementia like CJD. However, we have to keep CJD in mind in the diagnosis of hyperparathyroidism.  相似文献   
995.
996.
997.
Fas ligand (FasL), which induces apoptosis against Fas-expressing cells, has been found to be expressed on various cell types including cancer cells. Membrane-bound FasL is cleaved to release soluble FasL (sFasL). Although serum or plasma sFasL concentration has been reported to increase in various diseases, sFasL concentration in healthy normal persons has not been fully studied. There have been few reports on sFasL concentrations in patients with carcinomas. We measured plasma sFasL concentrations using an enzyme-linked immunosorbent assay in 155 healthy volunteers (70 males and 85 females with an average age of 41.5+/-15.4) and 112 patients with gastric carcinoma (76 males and 36 females with an average age of 62.3+/-11.5). A significant negative correlation existed between age and plasma sFasL concentration in healthy volunteers. sFasL concentrations in males were significantly lower than those in females. Plasma sFasL levels were significantly higher in patients with gastric carcinoma than in healthy volunteers when male subjects aged 50 or older were analyzed, although no significant difference existed between the groups in the age bracket of 35 to 49. Male patients aged 50 or older with stage 1B or 2 tumors showed significantly higher plasma sFasL concentrations than those with stage 1A tumors or those with stage 3 or 4 tumors. In conclusion, age- and gender-matched controls should be used when plasma sFasL concentration is investigated. The origin and physiological or clinical significance of plasma sFasL in healthy volunteers and gastric cancer patients remain to be clarified.  相似文献   
998.
The lack of an accurate system to predict the response to radiotherapy for individual cancer lesions remains a major clinical problem. The aim of this study was to establish whether heme oxygenase-1 (HO-1) may be useful in predicting radiosensitivity of esophageal cancers. We evaluated biopsy specimens from 13 esophageal squamous cell cancer patients. Of these, 8 patients had tumors responding to radiotherapy, and the remainder were considered radioresistant. Expression of HO-1 was assayed using a standard immunoperoxidase technique. Clinicopathological parameters were also analyzed as factors potentially contributing to radiosensitivity. Seven of 13 patients (53.8%) showed cytoplasmic staining for HO-1 in cancer tissues. The local treatment failure rate was 0% for HO-1 positive patients, as opposed to 83.3% for HO-1-negative patients (p=0.012). In contrast, tumor size, stage, and histologic grade were not significantly different between radiotherapy responders and non-responders to radiation therapy. No relationship was observed between HO-1 expression and clinicopathologic features. The results of the current study suggest that expression of HO-1 may be a useful indicator of radiosensitivity for esophageal cancer patients.  相似文献   
999.
BACKGROUND: Mitogen-activated protein kinase (MAPK) is one of the transforming growth factor-beta (TGF-beta signaling pathways while heat shock protein 70 (HSP70) prevents apoptosis by affecting MAPK signaling downstream. However, the interrelationship between TGF-beta and HSP70 signaling is still unknown. MATERIALS AND METHODS: DU-145 prostate cancer cells were treated with 40 pM and 200 pM TGF-beta1. After 3, 6, 9, 12 and 24 hours, cell proliferation assay and cell cycle analysis were performed. The activities of HSP70 and MAPKs (c-Jun N-terminal kinase 1 (JNK1), extracellular signal-regulated kinase 1 (ERK1), ERK2 and p38) were analyzed by Western blot at each time-point. RESULTS: TGF-beta1 inhibited the cell growth in a dose-dependent manner at 3 hours. Late G1 accumulation in the cell cycle was observed in a dose-dependent manner after 24 hours. HSP70 and JNK1 increased only at 3 hours and decreased for up to 24 hours thereafter. ERK1, ERK2 and p38 decreased from 3 to 24 hours after TGF-beta1 treatment. CONCLUSION: These data suggest that HSP70 does not prevent the inhibition of cell growth in DU-145 cells treated with TGF-beta1.  相似文献   
1000.
OBJECTIVE: To assess the feasibility and outcome of concurrent chemoradiotherapy (CT-RT) with large regional field and high-dose external beam boost irradiation in thoracic esophageal cancer. METHODS: Patients with clinical stage T1 (submucosal)-4N0-1M0 (UICC 1997) squamous cell carcinoma of the thoracic esophagus were eligible. Radiotherapy consisted of regional irradiation (extending from supraclavicular fossa to the paracardial area) with 39.6 Gy followed by high-dose external beam boost up to 66.6 Gy (1.8 Gy/day, five times per week). Two-hour infusion of cisplatin (80 mg/m(2) on day 1) and continuous infusion of 5-fluorouracil (800 mg/m(2)/day on days 2-6) were administered concurrently with radiotherapy, every 3-4 weeks, for two cycles. RESULTS: Thirty patients (stage I, 3; stage II, 11; stage III, 16) were entered into the study. Twenty-one patients (70%) completed the planned treatment. In elderly (> or = 70 years) patients, four of six withdrew. Grade 3 and 4 toxicities (NCI-CTC) were observed in 20 (67%) and three (10%) patients, respectively. Major toxicities were blood, gastrointestinal (i.e. nausea and esophagitis) and pulmonary. There was no grade 5 (fatal) toxicity. The median follow-up period for surviving patients was 27 months (range: 9-49 months). The median survival time was 21 months. The 1- and 2-year survival rates were 65 and 49% for all 30 patients. The incidence of esophageal stricture (grade 1-2: RTOG) was 21%. No patient suffered fistula formation. CONCLUSIONS: Despite poor compliance for elderly patients and frequent severe toxicities, our concurrent CT-RT resulted in a favorable outcome in thoracic esophageal cancer.  相似文献   
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