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31.
Dendritic cell leukemia (DCL) or hematodermic tumor is an uncommon subtype of acute leukemia. In contrast to adult cases, children tend to have a less aggressive course. The diagnosis of DCL should be considered when its characteristic morphologic features are present and leukemic cells co‐express CD4 and CD56. Cases of DCL among pediatric patients have been reported to respond to therapeutic regimens for acute lymphoblastic leukemia, but details regarding the specifics of therapy are lacking. Pediatr Blood Cancer 2013; 60: E38–E41. © 2013 Wiley Periodicals, Inc.  相似文献   
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BACKGROUND: If cervical polyps are a common pathology in the female adult population, giant cervical polyps with a size greater than 4 cm are rare and until now only several cases have been described in literature. The size and the clinical presentation can mimic a cervical neoplasia. The management is surgical and can be conservative regarding to the benign pathological feature of this entity. CASE REPORT: We report the case of a giant cervical polyp of 5.5 cm occurring in a multiparous 47-year-old woman who clinically presented vaginal bleeding. The lesion was resected by electrosurgery with no recurrence 7 months after surgery. CONCLUSION: The diagnosis, management and outcome of this rare entity had been reviewed according to the literature.  相似文献   
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The effect of renal impairment (RI) on risk of bleeding and recurrent thrombosis in cancer patients treated with direct oral anticoagulants for venous thromboembolism (VTE) is undefined. We ran a prespecified analysis of the randomized Caravaggio study to evaluate the role of RI as a risk factor for bleeding or recurrence in patients treated with dalteparin or apixaban for cancer-associated VTE. RI was graded as moderate (creatinine clearance between 30-59 mL/minute; 275 patients) and mild (between 60-89 mL/minute; 444 patients). In the 1142 patients included in this analysis, the incidence of major bleeding was similar in patients with moderate vs. no or mild RI (HR 1.06-95% CI: 0.53-2.11), with no difference in the relative safety of apixaban and dalteparin. Recurrent VTE was not different in moderate vs. no or mild RI (HR=0.67, 95% CI: 0.38-1.20); in moderate RI, apixaban reduced recurrent VTE compared to dalteparin (HR=0.27, 95% CI: 0.08-0.96; P for interaction 0.1085). At multivariate analysis, no association was found between variation of renal function over time and major bleeding or recurrent VTE. Advanced or metastatic cancer was the only independent predictor of major bleeding (HR=2.84, 95% CI: 1.20-6.71), with no effect of treatment with apixaban or dalteparin. In our study, in cancer patients treated with apixaban or dalteparin, moderate RI was not associated with major bleeding or recurrent VTE. In patients with moderate renal failure, the safety profile of apixaban was confirmed with the potential for improved efficacy in comparison to dalteparin. ClinicalTrials.gov identifier: NCT03045406.  相似文献   
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Background:Transcatheter aortic valve replacement (TAVR) is a worldwide adopted procedure with rapidly evolving practices. Regional and temporal variations are expected to be found.Objective:To compare TAVR practice in Latin America with that around the world and to assess its changes in Latin America from 2015 to 2020.Methods:A survey was applied to global TAVR centers between March and September 2015, and again to Latin-American centers between July 2019 and January 2020. The survey consisted of questions addressing: i) center’s general information; ii) pre-TAVR evaluation; iii) procedural techniques; iv) post-TAVR management; v) follow-up. Answers from the 2015 survey of Latin-American centers (LATAM15) were compared with those of other centers around the world (WORLD15) and with the 2020 updated Latin-American survey (LATAM20). A 5% level of significance was adopted for statistical analysis.Results:250 centers participated in the 2015 survey (LATAM15=29; WORLD15=221) and 46 in the LATAM20. Combined centers experience accounted for 73 707 procedures, with WORLD15 centers performing, on average, 6- and 3-times more procedures than LATAM15 and LATAM20 centers, respectively. LATAM centers performed less minimalistic TAVR than WORLD15 centers, but there was a significant increase in less invasive procedures after 5 years in Latin-American centers. For postprocedural care, a lower period of telemetry and maintenance of temporary pacing wire, along with less utilization of dual antiplatelet therapy was observed in LATAM20 centers.Conclusion:Despite still having a much lower number of procedures, many aspects of TAVR practice in Latin-American centers have evolved in recent years, followingthe trend observed in developed country centers.  相似文献   
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Selective targeted delivery of TNFalpha to tumor blood vessels   总被引:4,自引:0,他引:4       下载免费PDF全文
We sought to enhance the selective toxicity of tumor necrosis factor alpha (TNFalpha) to permit its systemic use in cancer therapy. Because ligand-targeted therapeutics have proven successful in improving the selective toxicity of drugs, we prepared a fusion protein (L19mTNFalpha) composed of mouse TNFalpha and a high-affinity antibody fragment (L19 scFv) to the extradomain B (ED-B) domain of fibronectin, a marker of angiogenesis. L19mTNFalpha was expressed in mammalian cells, purified, and characterized. L19mTNFalpha was an immunoreactive and biologically active homotrimer. Radiolabeled L19mTNFalpha selectively targeted tumor neovasculature in tumor-bearing mice, where it accumulated selectively and persistently (tumor-to-blood ratio of the percentage of injected dose per gram [%ID/g] of 700, 48 hours from injection). L19mTNFalpha showed a greater anticancer therapeutic activity than both mTNFalpha and TN11mTNFalpha, a control fusion protein in which an antibody fragment, irrelevant in the tumor model used, substituted for L19. This activity was further dramatically enhanced by its combination with melphalan or the recently reported fusion protein L19-IL2. In conclusion, L19mTNFalpha allows concentrating therapeutically active doses of TNFalpha at the tumor level, thus opening new possibilities for the systemic use of TNFalpha in cancer therapy.  相似文献   
37.
In this paper a robotic means of magnetic navigation of an endovascular device a few millimeters in diameter is presented. The technique, based on traditional computer-assisted surgery adapted to intravascular medical procedures, includes a manipulator for magnetic dragging interfaced with an ultrasound system for tracking the endovascular device. The main factors affecting device propulsion are theoretically analyzed, including magnetic forces, fluidic forces, and friction forces between the endovascular device and the vessel. A dedicated set-up for measuring locomotion, and for navigation with and against the flow, has been developed and preliminary tests have been performed to derive the best configuration for controlled magnetic dragging in the vascular system. Experimental outcomes are consistent with a simple analytical model that analyzes dragging of the magnetic capsule in a tube. By means of this model, different working conditions can be considered to select the appropriate conditions, for example flow rate, coefficient of friction, or magnetic properties.  相似文献   
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Caiman yacare is considered one of the top predators in the Amazon basin, and understanding pollutant distribution within its tissues may help its sustainable management. As a top predator, C. yacare should have the highest mercury concentrations, but has lower Hg concentrations than carnivorous fish (Rivera et al. 2016), which are part of their diet. We compared total Hg among liver, kidney, fat, and muscle of C. yacare, and whether trends in the distribution of Hg among tissues were like other crocodilians, aquatic birds, omnivorous, and carnivorous fish. Fat had the lowest concentrations (0.025 ± 0.03 mg kg−1) followed by muscle (0.15 ± 0.06 mg kg−1), kidney (0.57 ± 0.30 mg kg−1) and liver (1.81 ± 0.80 mg kg−1). Such preferential accumulation makes C. yacare meat a safer alternative for human consumption than carnivorous fish. The relation between Hg accumulation in liver and muscle is highest in crocodilians, which has evolutive and environmental implications.

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