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Two patients with Billroth II gastrectomy and choledocholithiasis are presented. Treatment with endoscopic retrograde cholangiography and dilatation with papillary balloon allowed lithiasis extraction. The evolution following the procedure was favorable with no complications being observed. The advantages and disadvantages of papillary balloon dilatation in comparison with endoscopic sphincterotomy are reviewed. 相似文献
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T Schmidt H Karsunky B R?del B Zevnik HP Els?sser T M?r?y 《Canadian Metallurgical Quarterly》1998,17(18):5349-5359
After rearrangement of the T-cell receptor (TCR) beta-locus, early CD4(-)/CD8(-) double negative (DN) thymic T-cells undergo a process termed 'beta-selection' that allows the preferential expansion of cells with a functional TCR beta-chain. This process leads to the formation of a rapidly cycling subset of DN cells that subsequently develop into CD4(+)/CD8(+) double positive (DP) cells. Using transgenic mice that constitutively express the zinc finger protein Gfi-1 and the serine/threonine kinase Pim-1, we found that the levels of both proteins are important for the correct development of DP cells from DN precursors at the stage where 'beta-selection' occurs. Analysis of the CD25(+)/CD44(-,lo) DN subpopulation from these animals revealed that Gfi-1 inhibits and Pim-1 promotes the development of larger beta-selected cycling cells ('L subset') from smaller resting cells ('E subset') within this subpopulation. We conclude from our data that both proteins, Pim-1 and Gfi-1, participate in the regulation of beta-selection-associated pre-T-cell differentiation in opposite directions and that the ratio of both proteins is important for pre-T-cells to pass the 'E' to 'L' transition correctly during beta-selection. 相似文献
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PJ del Nido 《Canadian Metallurgical Quarterly》1996,61(1):336-9; discussion 340-1
BACKGROUND: Extracorporeal membrane oxygenation (ECMO) support for cardiac failure has been used in children since 1981 at the Children's Hospital in Pittsburgh. Most children required support after cardiac operations. Recently, however, a larger number of patients with decompensated cardiomyopathy or myocarditis have been supported with ECMO, which was used as a bridge to transplantation in most. METHODS: From 1981 to 1994, 68 children were placed on ECMO for cardiac support. RESULTS: The overall survival for the entire time period was 38%, with the more recent experience survival increased to 47%. In 14 children, ECMO was used as a bridge to transplantation, with 9 children receiving a heart transplant and 7 long-term survivors. Extracorporeal membrane oxygenation has also been used to resuscitate 11 children after sudden cardiac arrest, with a long-term survival of 53%. CONCLUSIONS: We conclude that ECMO support for severe cardiac failure is effective. Patient selection and the use of heart transplantation for intractable heart failure have improved the overall survival. 相似文献
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Gabriella del Grosso Anna Gerardi Federico Marchetti 《Mathematics and computers in simulation》1984,26(4):373-376
Some probabilistic techniques are discussed regarding their use in estimating the principal eigenvalue of an elliptic operator. Such estimates are useful when studying models for biochemical reactions governed by lateral diffusion.In this paper we summarize recent results on some mathematical techniques that were developed to study certain biological models. 相似文献
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