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Late occurrence of cytomegalovirus (CMV) disease after day 100 after bone marrow transplantation has become an increasing problem; whether a quantitative measurement of CMV DNA in plasma by polymerase chain reaction (P-PCR) could be predictive of such disease was investigated. In a prospective study, 117 subjects undergoing allogeneic marrow transplantation were followed for 120 days with weekly CMV blood cultures, with day 35 bronchoalveolar lavage CMV cultures, with weekly CMV P-PCR, and with clinical follow-up for an additional 1-2 years. Despite preemptive ganciclovir, CMV disease occurred in 9% of subjects, with a median time of onset of 176 days. Quantitative CMV P-PCR was associated with the late development of CMV disease (P = .01). Of 43 subjects with positive P-PCR results, 23% developed CMV disease, but no disease occurred in the 74 subjects with negative P-PCR (P < .001), despite the fact that 22% had CMV isolated from lung lavage fluid and 32% had CMV isolated from blood.  相似文献   
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Any soft tissue swelling beneath the deep fascia should be considered a sarcoma until proven otherwise. As the most important factor in the primary treatment of these cancers is the adequacy of the primary surgical resection, it is vital to diagnose these malignant tumours pre-operatively. The modern treatment of soft tissue sarcomas may involve all modalities, but the most important aspect of treatment of a primary localised sarcoma is wide excisional surgery preserving limb function. Radiotherapy is a vital adjunct in high-grade tumours, or in tumours whose resectability is limited either by size or anatomical proximity to vital structures. Apart from a few chemosensitive sarcomas, the role of chemotherapy is limited to treatment of metastatic disease where documented response rates are no greater than 30%. As 50% of patients with high-grade sarcomas will die from metastatic disease, improvements in survival rates will only come from improvements in response to systemic therapy. No controlled trials have shown any survival benefit for adjuvant chemotherapy, although a recent meta-analysis of published data has shown a trend to increased survival at two years. Multicentre randomised trials are ongoing. The prognosis of these lesions is highly variable, but is intimately related to the anatomical site (i.e., resectability), and also the grade and size of the tumour.  相似文献   
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A simple, rapid, accurate and reproducible capillary electrophoretic method was developed for the assay of glycyrrhizin and glycyrrhetinic acid in traditional Chinese medicinal preparations. The buffer solution used in this method was acetonitrile and 0.02 M sodium dihydrogen-phosphate solution adjusted to pH 7.5 with 0.05 M sodium hydroxide. The linear calibration range was 0.04-2.00 mg/ml (r = 0.9988) for glycyrrhizin and 0.007-0.35 mg/ml (r = 0.9985) for glycyrrhetinic acid and recoveries were 98.1-101.3% for glycyrrhizin and 98.5-101.4% for glycyrrhetinic acid. The relative standard deviations were 1.02% (n = 6) for glycyrrhizin and 0.91% (n = 6) for glycyrrhetinic acid. The content of these two acids in Glycyrrhizae Radix and Glycyrrhizae Radix-containing Chinese medicinal preparations was successfully determined within 10 min.  相似文献   
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