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951.
Michael Joseph Emma C. Hamilton Andrea Hayes-Jordan Winston W. Huh Mary T. Austin 《Journal of pediatric surgery》2018,53(1):169-173
Purpose
The purpose of this study was to determine whether racial/ethnic disparities exist in disease presentation, treatment, and survival among children and adolescents with extremity sarcoma.Methods
The Surveillance, Epidemiology, and End Results (SEER) data were analyzed for patients < 20 years old with soft-tissue extremity sarcomas from 1973 to 2013. Multivariate logistic regression was performed to determine the association between race/ethnicity and disease stage at presentation and likelihood of surgical resection. Overall survival (OS) was evaluated using hazard ratios with 95% confidence intervals.Results
1261 cases were identified: 650 (52%) non-Hispanic whites (NHW), 313 (25%) Hispanics, 182 (14%) non-Hispanic blacks (NHB), and 116 (9%) other race/ethnicity. Logistic regression results showed that Hispanics and NHB were 51% and 44%, respectively, less likely to undergo surgical resection compared to NHW (OR = 0.49, 95% CI: 0.30–0.80; OR = 0.56, 95% CI: 0.32–0.98, respectively). Factors associated with failure to undergo surgical resection included histology, lower extremity site, tumor size, and distant metastases. OS based on race/ethnicity significantly differed using the log-rank test, with NHB having the worst survival (p < 0.05).Conclusions
We conclude that NHB, Hispanics, and other race/ethnicity were less likely to undergo surgical resection for extremity sarcoma. Further work is needed to better characterize and eliminate disparities in the management and outcomes of children with extremity sarcomas.Type of study
Prognosis study.Level of evidence
IV 相似文献952.
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Efficacy and safety of creatine supplementation in juvenile dermatomyositis: A randomized,double‐blind,placebo‐controlled crossover trial 下载免费PDF全文
Marina Yazigi Solis PhD Ana Paula Hayashi MS Guilherme Giannini Artioli PhD Hamilton Roschel PhD Marcelo Tatit Sapienza PhD Maria Concepción Otaduy PhD Ana Lucia De Sã Pinto PhD Clovis Artur Silva PhD Adriana Maluf Elias Sallum PhD Rosa Maria R. Pereira PhD Bruno Gualano PhD 《Muscle & nerve》2016,53(1):58-66
Introduction: It has been suggested that creatine supplementation is safe and effective for treating idiopathic inflammatory myopathies, but no pediatric study has been conducted to date. The objective of this study was to examine the efficacy and safety of creatine supplementation in juvenile dermatomyositis (JDM) patients. Methods: In this study, JDM patients received placebo or creatine supplementation (0.1 g/kg/day) in a randomized, crossover, double‐blind design. Subjects were assessed at baseline and after 12 weeks. The primary outcome was muscle function. Secondary outcomes included body composition, aerobic conditioning, health‐related quality of life, and muscle phosphocreatine (PCr) content. Safety was assessed by laboratory parameters and kidney function measurements. Results: Creatine supplementation did not affect muscle function, intramuscular PCr content, or any other secondary outcome. Kidney function was not affected, and no side effects were reported. Conclusions: Twelve weeks of creatine supplementation in JDM patients were well‐tolerated and free of adverse effects, but treatment did not affect muscle function, intramuscular PCr, or any other parameter. Muscle Nerve 53 : 58–66, 2016 相似文献
955.
Regulation of midgut defensin production in the blood-sucking insect Stomoxys calcitrans 总被引:1,自引:0,他引:1
The Stomoxys midgut defensin (Smd) family of genes are exclusively expressed in the anterior midgut of adult flies. Their putative function is protection of the stored bloodmeal from microbial attack. Smd genes are constitutively expressed, up-regulated in response to a bloodmeal and further up-regulated by immune stimulation per os but only in the presence of a bloodmeal not a sugar meal. Smd genes are down-regulated in response to a systemic immune challenge. Smd gene constructs transfected into l(2)mbn cells undertake constitutive expression but are not up-regulated by immune challenge. Electrophoretic mobility shift assays (EMSA) suggest the rel-like sites in the proximal promoter region of Smd genes do not bind midgut factors and so are non-functional. 相似文献
956.
Modulation of gene expression in subjects at risk for colorectal cancer by the chemopreventive dithiolethione oltipraz. 总被引:6,自引:0,他引:6 下载免费PDF全文
957.
Purinergic receptors on insulin-secreting cells 总被引:5,自引:0,他引:5
D. Hillaire-Buys J. Chapal G. Bertrand P. Petit and MM Loubatières-Mariani 《Fundamental & clinical pharmacology》1994,8(2):117-127
Summary— The insulin secreting B cell is fitted with the two types of purinergic receptors: P2 (for ATP and/or ADP) and P1 (for adenosine). The activation of P2 purinoceptors by ATP or ADP evokes a biphasic stimulation of insulin secretion from isolated perfused rat pancreas; this stimulation is dose-dependent between 10?6 and 10?4 M. Non hydrolysable structural analogues are also effective, and the relative potency of various agonists (2-methylthio ATP ? ATP = ADP = α, β-methylene ATP ? AMP) gave evidence for a P2y purinoceptor subtype. Proposed mechanisms include both an increased Ca2+ uptake and an increased intracellular Ca2+ mobilization via the hydrolysis of polyphosphoinositides. ATP (or ADP) potentiates physiological insulin-secreting agents (glucose and acetylcholine) and P2 purinoceptors could play a physiological role in the stimulation of insulin secretion. The activation of P1 purinoceptors (adenosine receptors) decreases insulin secretion. Using structural analogues of adenosine, the receptor was characterized as an A1 subtype; it is coupled to a pertussis toxin sensitive G protein and it inhibits adenylate cyclase. It is of physiological relevance that the B cell has the two types of purinoceptors with opposite effects. Recently, a metabolically stable structural analogue of ADP, adenosine-5′-0-(2-thiodiphosphate) or ADPßS, has been described as a potent secretory agent, effective at nanomolar concentrations on isolated perfused rat pancreas. In vivo, this substance is able to increase insulin secretion and to improve glucose tolerance after IV administration in rats and oral administration in dogs. Furthermore in streptozotocin-induced diabetes, ADPßS retains its insulin secreting effects. These results suggest that P2y purinoceptors could be a new target for antidiabetic drugs. 相似文献
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