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81.
Evaluation of phagocytic cell function in an ex vivo model of hemodialysis   总被引:1,自引:0,他引:1  
An ex vivo model of hemodialysis was used to evaluate the effect of dialysis membranes on phagocytic cell function. Blood was withdrawn continuously from healthy, non-uremic donors, heparinized, and pumped, single pass, through membrane modules under conditions which simulated normal dialysis conditions. The membrane modules contained membranes of cellulose, DEAE-substituted cellulose, or polysulfone. Blood was obtained from the module outlets for determination of complement activation, phagocyte elastase release, zymosan-induced phagocyte chemiluminescence, and monocyte interleukin-1 production. Significantly less complement activation occurred with the polysulfone and DEAE-substituted cellulose membranes than with cellulose membranes. Normal monocyte interleukin-1 production was not stimulated by any of the membranes used. In contrast, the cellulosic, but not the polysulfone, membranes primed the oxidative burst of the phagocytes and caused them to release elastase. DEAE-substituted cellulose had a lesser effect on elastase release than did cellulose and elastase release correlated significantly with the degree of complement activation. However, the correlation between complement activation and priming of phagocyte oxidative burst was weak, suggesting that membranes affect phagocyte oxidative metabolism through more than one mechanism. We conclude that some dialysis membranes stimulate the bacteriacidal functions of normal phagocytic cells, in part through complement-dependent mechanisms.  相似文献   
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Multiple reports of cauda equina syndrome and transient radicular nerve root irritation have suggested that lidocaine spinal anesthesia may be responsible. In this case report, a patient with a preexisting diabetic neuropathy received a partial block following a tetracaine spinal, which was followed by a lidocaine spinal. Following block resolution, a new conus medullaris syndrome was diagnosed. Because of the close proximity of the cauda equina and the conus medullaris, differentiation between these syndromes can be difficult. The preexisting diabetic neuropathy may have predisposed this patient to neurologic injury. The choice of a different local anesthetic drug with less neurotoxic potential such as bupivacaine may have prevented this injury.  相似文献   
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We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences.  相似文献   
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Twenty-five persons with diabetes (aged 55–83 years) who were living independently in the community, and 40 age- and sex-matched non-diabetic controls were assessed for tactile sensitivity, vibration sense, proprioception, quadriceps strength and body sway. In both men and women, those with diabetes performed significantly worse in tests of body sway on firm and compliant surfaces compared with the control subjects after controlling for weight and body mass index. The female diabetic subjects also performed significantly worse in tests of peripheral sensation and strength compared with controls. Age-related declines in sensori-motor function were greater in the diabetic group (r = 0.55–0.75) than in the controls (r < 0.44), while within the diabetic group, duration of diabetes and vibration sense were significantly correlated with sway on a compliant (foam rubber) surface with the eyes open (partial r = 0.52, p < 0.01 and r = 0.55, p < 0.01, respectively). The study findings provide evidence that older people with diabetes have problems with stability and related sensori-motor factors which may place them at increased risk of falls.  相似文献   
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OBJECTIVE: In 1991, a randomized study was published and demonstrated that use of nonsurgical therapy (chemoradiation) provided similar survival to total laryngectomy (the gold standard) for patients with advanced-stage laryngeal cancer. The purpose of this study was to assess how treatment of advanced laryngeal cancer was influenced by such developments in non-surgical therapy. STUDY DESIGN: Patterns of care study using National Cancer Database (1985-2001). RESULTS: The percentage of advanced-stage patients treated with chemoradiation increased from 8.3% to 20.8% while the proportion treated with radiation alone decreased from 38.9% to 23.0%. Use of chemoradiation increased at a significantly faster rate after the 1991 publication at both community cancer centers and teaching research facilities. The use of total laryngectomy decreased slightly during this period. CONCLUSIONS: The use of chemoradiation increased after the 1991 publication. It was impossible to determine from the NCDB whether additional patients who could benefit from chemo-RT were not offered or did not complete this treatment option. We recommend that treatment recommendations discussed at tumor boards be recorded in cancer registries.  相似文献   
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