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Summary Allotransplantation of solid organs transfers passenger leucocytes which may give rise to a state of persistent microchimaerism. In this report we describe the case of a patient who developed a solitary plasmacytoma in a transplanted kidney more than 10 years after allografting. The diagnosis was established on the basis of the presence of a monoclonal IgG kappa peak in the serum, and light chain proteinuria, the plasmacytoid features of tumour cells including cell surface expression of IgG, kappa light chains, CD20, CD38 and CD56, the absence of lytic bone lesions and a normal bone marrow biopsy, and the disappearance of the monoclonal IgG peak after graft nephrectomy. A donor origin of the tumour was established by HLA DNA typing of tumour, tumour-free kidney tissue, and peripheral blood leucocytes, respectively.  相似文献   
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Abstract: To ascertain whether the diet of young students in health-related courses conformed to Australian dietary targets for 1995 and to identify nutritional needs in view of dietary targets for 2000, 246 undergraduate students analysed their weighed diet for three or five days. Eight often male participants were meeting the dietary goals for 1995 for fibre and fat intake and six of ten were meeting the goals for 2000. More female participants were meeting the goals for fat, but less than half of the females were meeting the 1995 goals for fibre. Some 84 per cent of females, but only 29 per cent of males, were meeting the 1995 dietary goals for sodium. Few participants derived 10 per cent or less of their energy from saturated fat or 10 per cent of their energy from polyunsaturated fatty acids. Substantial numbers of participants failed to meet the recommended daily intakes of zinc, calcium, magnesium and iron (females). Education of specific subgroups and modifications to food production and processing are proposed.  相似文献   
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A structural model for the genome of echovirus 22   总被引:1,自引:0,他引:1  
Summary We have proposed previously that the structural model for the echovirus 22 genome is a single-stranded RNA molecule that has folded back upon itself to form a stable hairpin at the 5-terminus. The vRNA of echovirus 22 has been characterized further by digestion with selective ribonucleases, electrophoresis in composite gels, hydrodynamic studies in density gradients of Cs2SO4 and sucrose, thermal denaturation and 3-terminal ribonucleotide analysis. Based on these observations, the genome of echovirus 22 is a single-stranded RNA molecule having a region of secondary structure located at the 5-terminus that may be characterized as a snapback hairpin with hydrogen-bonded base-pairing. In addition, a VPg-like protein is attached (presumably to the 5-end of the RNA) and the 3-terminus contains a polyadenylic acid tract [poly(A)].  相似文献   
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The mammalianCAD gene codes for a 240-kDa multifunctional protein that catalyzes the first three steps of de novo pyrimidine biosynthesis. Previously, the longest cDNA construct available was missing approximately 500 bp of coding sequence at the 5 end, thereby lacking the sequence to encode the entire carbamylphosphate synthetase (CPSase) domain. Here, a completeCAD hamster cDNA is constructed, placed into a mammalian expression vector, and transfected into hamster cells deficient in CAD. Transfectants show coordinately restored levels of all three enzyme activities and the presence of full-length CAD protein. A derivative construct of theCAD cDNA was generated that should encode only the CPSase domain. When transfected into mammalian cells, a protein was synthesized that had significant CPSase activity both in vivo and in vitro. The two constructs generated in this study will facilitate the study of CAD structure, function, and allosteric regulation.  相似文献   
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Patient-controlled epidural analgesia: demand dosing   总被引:17,自引:0,他引:17  
A double-blind, placebo-controlled study was designed to compare the efficacy of demand-dose patient-controlled epidural analgesia (PCEA) with continuous epidural infusion (CEI) for treatment of pain during labor and delivery. Forty patients were randomized to receive 0.125% bupivacaine with fentanyl (2 micrograms/mL) through CEI at 12 mL/h or through demand-dose PCEA. Patients using PCEA could demand 3 mL every 10 min without restriction. Analgesia in both groups was comparable. However, there was a significant reduction in total bupivacaine consumption (in milligrams) associated with the use of PCEA (mean +/- SEM: CEI = 76.1 +/- 8.5 mg; PCEA = 42.2 +/- 5.9 mg; 45% reduction). The hourly bupivacaine consumption during the first (CEI = 15.8 +/- 0.6 mg/h; PCEA = 8.8 +/- 1.1 mg/h) and second (CEI = 17.2 +/- 1.2 mg/h; PCEA = 6.8 +/- 1.2 mg/h) stages of labor was also reduced. Overall, this represented a 47% "sparing" of bupivacaine use per hour with PCEA. Similar reductions occurred in the use of fentanyl. The reductions in analgesic requirement, however, were not associated with a reduction in the degree of motor blockade or in the cephalad extent of sensory blockade. A significant dose-sparing effect was associated with the use of demand-dose PCEA as compared with standard CEI for analgesia during labor and delivery.  相似文献   
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Primary tracheal schwannoma   总被引:4,自引:0,他引:4  
We report a case of a primary tracheal schwannoma causing symptoms of airway obstruction in a 33-year-old man. Bronchoscopy and computerized tomography demonstrated a polypoid intratracheal mass obstructing 90% of the lumen. Tracheal resection with primary anastomosis was performed. Histologic analysis revealed a benign neurogenic tumor of Schwann cell origin.  相似文献   
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