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61.
The anterior mandible defect following cancer excision presents a formidable reconstructive challenge. A trapezius osteomyocutaneous island flap based on the transverse cervical vessels is described which allows immediated reconstruction of the entire defect. The various classes of bone flaps retaining an intact vascular pedicle are discussed. The osseous extension of the trapezius island flap appears to be adequately perfused. The anatomy involved and the orthopedic sequelae of using this flap are discussed.  相似文献   
62.
The EEG examination of 45 patients with vascular headache and 44 patients with tension headache showed abnormal EEG's in 71% of the cases with migraine and 35% of the cases with tension headache. The examination of morphology and topography of alpha-rhythm and driving-effect during photic stimulation showed statistically significant differences between both groups. Applying specific characteristics in the EEG it is possible to differentiate both types of headache.  相似文献   
63.
A case of an isolated lesion of the thoracic spine attributed to SAPHO syndrome is presented. A 51-year-old man was referred for inflammatory pain in the thoracic spine. The general examination was normal (especially cutaneous and rheumatologic examinations). Laboratory analysis showed only a mild inflammatory reaction. Standard radiographs showed partial condensation of T8. Computed tomography showed osteolysis of the anterior corner of T8, and MRI revealed an abnormal signal of T8, with enlargement of the prevertebral soft tissue. Percutaneous and thoracoscopic biopsies showed a nonspecific inflammatory process, and cultures were sterile. Initially, several diagnoses were advanced: infectious spondylitis, malignant tumor, lymphomas, Paget disease, seronegative spondyloarthropathies and finally atypical SAPHO syndrome. Three months later, the patient experienced more pain. General examination was still normal. The radiological findings worsened, while the inflammatory blood tests were normal. A new thoracoscopic biopsy revealed a nonspecific inflammatory process. A diagnosis of SAPHO syndrome was made, despite the lack of typical lesions. Dramatically improving with anti-inflammatory therapy, the patients condition was favorable at 3-year follow-up. This atypical presentation of an isolated lesion in the spine makes the diagnosis of a SAPHO syndrome difficult but possible. Spine surgeons must be aware of this rare entity, to avoid misdiagnosis and unnecessary repeated surgical biopsies.  相似文献   
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Effects of anxiety on perceptual-motor organisation of rhythmical forearm movements were examined using an interrupted time series design with staggered baselines. Participants were exposed to repeated baseline sessions interrupted with two anxiety-inducing sessions. Results showed that under moderate levels of anxiety, determined from CSAI-2 and heart rate data, phase relations between oscillating forearms became more stable in in-phase (0 degrees ) and anti-phase (180 degrees ) modes, although these patterns were not maintained in baseline sessions following the anxiety manipulation. Data were consistent with participants employing a strategy of allocating greater attentional effort in stabilizing preferred co-ordination patterns under anxiety-inducing conditions. Results suggest that anxiety can temporarily act as a source of behavioural information, leading to the re-parameterisation of participants' intrinsic dynamics.  相似文献   
66.
The lysogenic state of bacteriophage lambda is exceptionally stable yet the prophage is readily induced in response to DNA damage. This delicate epigenetic switch is believed to be regulated by two proteins; the lysogenic maintenance promoting protein CI and the early lytic protein Cro. First, we confirm, in the native configuration, the previous observation that the DNA loop mediated by oligomerization of CI bound to two distinct operator regions (O(L) and O(R)), increases repression of the early lytic promoters and is important for stable maintenance of lysogeny. Second, we show that the presence of the cro gene might be unimportant for the lysogenic to lytic switch during induction of the lambda prophage. We revisit the idea that Cro's primary role in induction is instead to mediate weak repression of the early lytic promoters.  相似文献   
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Background Pancreatic cancer has a dismal prognosis. Few patients are suitable for surgical resection, leaving the majority requiring symptom palliation. Current palliative techniques such as surgical bypass and endoscopic retrograde cholangiopancreatography (ERCP) are imperfect. A novel palliative therapy combining the symptom control of surgical bypass with the minimally invasive nature of ERCP is required.Methods Perductal electrolytic ablation of pancreatic tissue, in a porcine model, was performed. There were two survival groups of 2 weeks (n = 4) and 8 weeks (n = 4). Postoperatively, serum biochemistry, amylase and C-reactive protein (CRP) were assessed. Histological examination of the pancreas, lungs, and kidneys was performed to determine the presence of acute pancreatitis or systemic inflammatory response.Results An immediate transient increase in both amylase and CRP was seen. Although pancreatic histology demonstrated localised necrosis at the electrolytic site at 2 weeks, there was no evidence of generalized pancreatitis or a systemic inflammatory response at either 2 or 8 weeks.Conclusions This study suggests that, although there is localized pancreatic necrosis and transient hyperamylasemia, perductal pancreatic electrolytic ablation is safe, with neither generalized pancreatitis nor a systemic inflammatory response, in the medium and long term. Although performed in normal porcine pancreas, because of the absence of a large-animal model of pancreatic cancer, this study suggests that electrolytic pancreatic ablation is safe. This technique may have a role in the palliation of pancreatic cancer, especially if delivered via a minimally, invasive approach, and warrants further investigation.  相似文献   
69.
OBJECTIVES: To investigate different dose combinations of amprenavir and delavirdine in order to assess an optimal dose suitable for clinical use. METHODS: This was a prospective, open-label, controlled, three-period, multiple-dose study with nine healthy volunteers. The volunteers received three different dose combinations of amprenavir and delavirdine twice a day for 10 days with a subsequent 12 h pharmacokinetic evaluation. Combination 1: amprenavir 600 mg and delavirdine 600 mg; combination 2: amprenavir 600 mg and delavirdine 800 mg; combination 3: amprenavir 450 mg and delavirdine 1000 mg. The combinations were taken at least 2 weeks apart. RESULTS: Differences in median delavirdine Cmax, C12 and AUC0-12 were seen when comparing the three combinations (3 > 2>1) (P<0.04). A considerable and clinically important higher median C12 was seen with combination 3 when compared to combination 1 (835 to 3944 ng/mL) (P=0.0039). Only small differences in the amprenavir pharmacokinetic parameters were seen between the three dose combinations, with a median C12 of 412, 434 and 536 ng/mL, respectively. CONCLUSIONS: In this study, an increase of 472% in median delavirdine C12 was seen with a delavirdine dose increase of only 67% (600 to 1000 mg). Saturation of the CYP3A4 enzymes and/or possibly also P-glycoprotein could be involved. Combination 3 was considered most suitable for clinical use, but because of the large inter-individual variation in steady-state concentrations, the use of the combination should be supported by therapeutic drug monitoring and restricted to certain patients.  相似文献   
70.
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