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MB Heyman JM LaBerge KA Somberg P Rosenthal C Mudge EJ Ring JD Snyder 《Canadian Metallurgical Quarterly》1997,131(6):914-919
The transjugular intrahepatic portosystemic shunt procedure is an accepted treatment for adults with complications of portal hypertension. We performed a retrospective review of all pediatric TIPS placements performed at the University of California, San Francisco between 1990 and 1996. Twelve procedures were attempted in nine children, with a mean age (+/- SD) of 9.4 +/- 3.9 years (range, 5 to 15 years) and a mean weight of 31 +/- 18 kg (range, 16 to 70 kg). The indications for TIPS placement were portal hypertension complicated by chronic variceal hemorrhage not controlled with sclerotherapy (n = 7) and hypersplenism with thrombocytopenia (n = 2). TIPS placement was successfully completed initially in seven of nine (78%) patients. Unfavorable vascular anatomy was the cause of failure in two cases. The seven patients who underwent successful TIPS placement were followed up for an average of 136 days (range, 1 to 800 days); two still have patent shunts, three underwent liver transplantation, one had a splenorenal shunt after stenosis, and one died of underlying liver disease. Variceal bleeding was controlled in four of five patients who successfully underwent TIPS placement. Shunt occlusion occurred in four patients; patency was restored by transjugular shunt revision in three, and a splenorenal shunt was performed in one. 相似文献
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MG McInnis A Chakravarti J Blaschak MB Petersen V Sharma D Avramopoulos JL Blouin U K?nig C Brahe TC Matise 《Canadian Metallurgical Quarterly》1993,16(3):562-571
A genetic linkage map of human chromosome 21q (HC21q) containing 43 markers genotyped by the polymerase chain reaction in the CEPH pedigrees is presented. The markers placed on this map are highly polymorphic with an average heterozygosity of 61%. The average interval size of the markers localized at 1000:1 odds is 2.5 cM. The map has a total length of 65.5 cM, with male and female lengths of 47.7 and 83.3 cM, respectively. The genotypes used in the construction of this map were subjected to rigorous error checking, which is reflected in the shorter map length compared to previous maps; the estimated error rate in genotyping is less than 0.04%. As noted in previous linkage maps there is increased recombination in females on proximal HC 21q and in the male in a region near the telomere. This map of HC 21 represents a highly informative and dense meiotic linkage map and will be useful in linking disease phenotypes to loci on this chromosome. 相似文献
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Cationic liposomes bound to plasmid DNA are currently used for in vitro and in vivo gene therapy applications, but such complexes readily form large, heterogeneous aggregates that are not appropriate for pharmaceutical development. More importantly, size heterogeneity makes studies focused on optimizing gene transfer to cells difficult to conduct or understand. For this reason we have evaluated the effect of microprobe sonication on these complexes in an effort to achieve process-controlled size homogeneity. Complexes were prepared using a 7.2 kb reporter plasmid and the following liposomal lipid combinations: DDAB/DOPE (50:50 mol %), DDAB/DOPE/PEG-PE (50:45:5 mol %), DDAB/EPC (50:50 mol %), DDAB/EPC/PEG-PE (50:45:5, 50:40:10, 50:35:15 mol %), DODAC/DOPE (50:50 mol %), and DODAC/EPC (50:50 mol %) (DDAB, dimethyldioctadecylammonium bromide; DOPE, dioleoylphosphatidylethanolamine; PEG-PE, monomethoxypolyethylene glycol2000 succinate- distearoylphosphatidylethanolamine; EPC, egg phosphatidylcholine; DODAC, dioleoyldimethylammonium chloride). The influence of complex composition and lipid:DNA ratio was evaluated. Particle size was determined before and after complexation and again after sonication using the quasi-elastic light scattering technique. DNA integrity was assessed via agarose gel electrophoresis. Finally, gene transfection was evaluated using CHO cells that were transfected in vitro with sonicated and unsonicated complexes. It is established in this study that size reduction can occur, but this is dependent on cationic and neutral lipid composition and, in some cases, lipid:DNA ratio. Surprisingly, the process of sonication leaves a significant percentage of the plasmid DNA intact and capable of in vitro transfection. This study shows that plasmid DNA can be protected from damage due to sonication by liposome complex formation. This may indicate that more common pharmaceutical methods for size reduction which subject particles to mechanical stress may be applicable in preparation of liposome/DNA formulations for in vivo application. 相似文献
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PN Hawkins S Richardson DM Vigushin J David CR Kelsey RE Gray MA Hall P Woo JP Lavender MB Pepys 《Canadian Metallurgical Quarterly》1993,36(6):842-851
OBJECTIVE: To evaluate aspects of the natural history of AA amyloidosis complicating juvenile rheumatoid arthritis (JRA), and its response to therapy with chlorambucil. METHODS: Scintigraphy and 7-day turnover studies were performed in JRA patients with histologically proven (n = 35) or clinically suspected (n = 30) AA amyloidosis, following intravenous injection of 123I and 125I-labeled serum amyloid P component (SAP). Prospective monitoring studies were performed over 2-3 years in 20 patients with amyloidosis. All but 2 amyloidosis patients were treated with chlorambucil. RESULTS: Positive scanning results were obtained in all patients in whom imaging was performed within 12 years of positive biopsy findings of amyloid and in 5 patients with clinically suspected amyloidosis. Negative scanning results with normal SAP metabolism, indicating regression of amyloid, were obtained in 4 patients whose amyloidosis had been in full clinical remission for more than 12 years. Prospective monitoring studies in patients whose JRA-associated inflammatory activity was in remission demonstrated regression of amyloid in 8 patients and no substantial changes in 8 others; however, in 4 further patients with active inflammation, there was accumulation of amyloid. There was a very poor correlation between the amount of amyloid present at a particular site and the resultant organ dysfunction. CONCLUSION: Radiolabeled SAP scintigraphy and turnover studies are useful complementary tools in the diagnosis, screening, and quantitative monitoring of type AA amyloidosis in JRA. The amyloid deposits may progress and/or regress at different rates in different anatomic sites over short periods. 相似文献
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M Pomerantz JR Denton GA Huitt JM Brown LA Powell MD Iseman 《Canadian Metallurgical Quarterly》1996,62(4):990-993
BACKGROUND: In a series of 229 patients infected with mycobacterial organisms, we noted a specific female phenotype that involves isolated infections of the middle lobe and lingula. METHODS: Thirteen patients were found to have infections of the middle lobe, lingula, or both. All of them were infected with Mycobacterium other then Mycobacterium tuberculosis, all were women, 12 of the 13 were slender, and most had variable combinations of skeletal abnormalities. All underwent resection of the middle lobe, lingula, or both. RESULTS: There were no operative deaths. Only 2 patients have had reactivation requiring additional antibiotic therapy. All patients have had a decreased number of pulmonary infections in the postoperative period. Anatomic findings at operation included a complete major fissure and at least a partially complete minor fissure with middle lobe resections or an elongated lingula. CONCLUSIONS: Mycobacterial infection of the middle lobe and lingula is primarily a disease of asthenic women and is often associated with skeletal abnormalities and complete fissures or an elongated lingula. We recommend that surgical intervention be performed early once the condition is identified. 相似文献
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Two patients are presented where internal mammary artery grafting was performed for the relief of symptomatic coronary artery disease. At follow-up the internal mammary artery was occluded and a communication between the internal mammary vein and the native coronary artery was demonstrated. These patients were characterised by the early recurrence of angina or the appearance of a continuous murmur. Both patients were treated by re-operation with ligation of the arterio-venous fistula and saphenous vein grafting. 相似文献