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A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
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In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems.  相似文献   
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Despite the advent of drug-eluting stents and dual antiplatelet therapy in the interventional management of cardiovascular disease, restenosis rates remain high with significant sequelae. Endovascular brachytherapy—popular in the 1990s and early 2000s—has recently resurfaced as a cost-effective treatment option. In this work, we outline the history of endovascular brachytherapy starting with its earliest promise in the 1990s. We discuss the development of drug-eluting stents and dual antiplatelet strategies and their impact on the perceived benefit of endovascular brachytherapy. For the contemporary era, we propose novel roles for endovascular brachytherapy in complex coronary artery disease and in high-risk patients managed with drug-eluting stents. We discuss the impetus for reducing the requirement and duration of dual antiplatelet therapy using endovascular brachytherapy. We also review innovative opportunities for endovascular brachytherapy after bare-metal stent placement in both coronary and noncoronary territories and offer economic arguments in favor of endovascular brachytherapy. Trials of endovascular brachytherapy in these regimes are merited.  相似文献   
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手术是脉管性病变治疗的一种手段,其主要作用是与放射治疗及各种药物治疗协同作用。对于血管瘤患者,手术仅限于普萘洛尔治疗无效,出现并发症及位于眼部的病变。整形手术可使血管瘤消退后遗留的面部畸形得到改善。对于一些范围较小的局灶性病变,手术往往可以取得满意的效果;对于巨大、多发的血管瘤,手术治疗往往作用有限,常常为减瘤术。手术患者一般在术前均经过栓塞硬化治疗,这样可以大大减少术中出血。手术无法治愈脉管性疾病,是一种辅助  相似文献   
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Background &; aim. Metabolic abnormalities are common in chronic hepatitis C infection (CHC). However, the genotypic differences of these disarrangements in patients infected with CHC genotype 4 (HCV-4) and its association with liver histology and viral loads remain unknown.Material and methods. We consecutively enrolled 183 HCV-4 patients and 106 healthy matched controls; to compare metabolic profiles and assess pattern of association of HCV RNA levels as well as histological factors with the serum lipid profile.Results. HCV-4 infection is associated with higher homeostasis model assessment of insulin resistance (HOMA-IR) index, despite that, a favourable lipid pattern, consisting of an elevation in HDLC and a reduction in serum cholesterol (TC), LDL-C and triglyceride (TG) levels, in comparison with normal matched adults. Significant fibrosis was independently associated with HOMA-IR, portal/periportal inflammation grade, serum cholesterol and age. Univariate association was elucidated between lower LDL-C and TC and Metavir activity score and between higher TG and TC and steatosis. In multivariate analysis, severe hepatitis activity, milder hepatic fibrosis, and triglyceride levels are associated with higher HCV RNA levels.Conclusion. HCV-4 is associated with wide metabolic changes. A proportional relationship is found between serum lipid profiles and hepatitis C viral load and liver histology in patients with HCV-4.  相似文献   
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CALLA-positive myeloma: an aggressive subtype with poor survival   总被引:5,自引:0,他引:5  
Durie  BG; Grogan  TM 《Blood》1985,66(1):229-232
Detailed immunotyping was carried out on 21 direct myeloma bone marrow aspirates and eight human myeloma cell lines. Four previously untreated common acute lymphoblastic leukemia antigen (CALLA)-positive myeloma patients were identified and six of eight cell lines (75%) were also positive. CALLA positivity, as part of an immature B phenotype, was found to correlate with very aggressive clinical disease: median survival six months v 56 months for the CALLA-negative group.  相似文献   
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