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Both non swellable and swellable poly(EGDMA/HEMA) microbeads were produced by suspension copolymerization. These microbeads were modified by immobilization of a spacer-arm (hexamethylene diamine (HMDA)) and protein A. The optimal values for modifications were as follows: sodium periodate concentration, 1.0 mgml(-1); HMDA concentration, 4 mgml(-1); and glutaraldehyde concentration, 0.070 microgml(-1). Adsorption of protein A onto the plain and periodate oxidized poly(EGDMA/HEMA) microbeads were very close to each other, and were 0.01-0.02 mg protein A on the 1-g Microbeads I and II, respectively. Protein A immobilization on poly(EGDMA/HEMA) microbeads were studied at different temperatures, times, and pHs using single protein solution containing different amounts of proteins. The optimal values for immobilization were as follows: the initial protein A concentration, 0.1 mgml(-1); temperature, 25 degrees C; pH, 9.5; and immobilization time, 120 min. Incorporation of protein A resulted in 1.420 and 1.825 mg protein A on the 1-g Microbeads I and II, respectively. HIgG adsorption capacity on the protein A-incorporated poly(EGDMA/HEMA) microbeads is 27 and 35 mg HIgGg(-1) polymer for Microbeads I and II, respectively.  相似文献   
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Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification.  相似文献   
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The vasodilatation induced by acetylcholine (ACh) in a rabbit isolated perfused kidney was abolished when the tissue was exposed to cold ischemia for 72 h in Euro-Collins (EC) solution. This vasodilatation is due to the release of endothelium-derived relaxing factor (EDRF) from renal vasculature as evidenced by the attenuation following methylene blue pretreatment. When kidneys were preserved in EC solution containing UK 38 485, a thromboxane synthase inhibitor, or nicardipine, a calcium channel blocker, ACh-induced vasodilatation persisted after 72 h of cold ischemia. These results were taken as evidence of tissue protective activity of UK 38 485 and nicardipine and have promising implications for cadaveric kidney transplantation.This paper was presented at the 35th World Congress of the International Society of Surgery in Hong Kong in August 1993  相似文献   
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The most common pattern in subacute sclerosing panencephalitis, is in the cerebral hemisphere white matter on T2-weighted images with or without atrophy. Brain-stem lesions are rare. We report brain-stem involvement in two children with subacute sclerosing panencephalitis. A peculiar pattern, with involvement of the pons with extension to both middle cerebellar peduncles and substantia nigra but sparing the pontine tegmentum, is suggested. Received: 10 January 2000/Accepted: 18 April 2000  相似文献   
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Intraosseous lipomas are among the most uncommon bone tumors. They arise most often in the appendicular skeleton. There are very few reported cases of intraosseous lipomas within the skull bones. We report a case of intraosseous lipoma of the frontal bone with conventional radiography and CT findings.  相似文献   
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Placental site trophoblastic tumor is a rare neoplasm that arises from intermediate trophoblasts and shows diversity of biological behaviors, resulting in the absence of consistency in treatment modalities. A case of placental site trophoblastic tumor that extended to the cervix, with primary manifestation of amenorrhea and yellow foul-smelling vaginal discharge, is presented. Total abdominal hysterectomy was performed initially, and serial measurements of human chorionic gonadotropin levels were obtained. She was admitted with metastases to brain and lung 1.5 years after surgery. Combination chemotherapy (etoposide-methotrexate-dactinomycin/cyclophosphamide-vincristine) and radiotherapy were administered. There was no significant response to chemoradiotherapy. Despite changing chemotherapy regimen, she is still alive with progressive disease.  相似文献   
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OBJECTIVE: To evaluate symptomatic response and recurrence rates of graduated topical fluorinated corticosteroid in patients with vulvar squamous cell hyperplasia. METHODS: Nine hundred seventy-six patients with biopsy-proven vulvar squamous cell hyperplasia from 1990 to 2003 were reviewed in this retrospective study. All patients were treated with graduated topical fluorinated corticosteroid. Data were obtained from hospital records. Symptomatic remission and recurrence rates were noted following six months local therapy. RESULTS: The mean age was 42.55+/-10.93 (15-85). The remission rate was 93.8% in six months. The remission rate was non-significantly higher in postmenopausal patients than that in their premenopausal counterpart (94.9% vs 93.0%, p=0.15). The disease recurred in 6.9% of patients. Of the patients that suffered recurrence 47.5% had persistent disease initially. The patients with following factors older ages (>40 years), postmenopausal period had significantly higher recurrence rates. Four patients with recurrent disease and six patients with persistent disease in the form of vulvar intraepithelial neoplasia I-II or atypical squamous hyperplasia, were treated with skinning vulvectomy. CONCLUSION: Corticosteroid in the treatment of vulvar squamous cell hyperplasia yielded excellent response rates. In the evaluation of patients without symptomatic relief, the first step should be a vulvar biopsy to exclude the presence of atypical components.  相似文献   
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