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41.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
42.
目的在β-受体激动情况下,研究多非替利衍生物CPU 228对电刺激触发心肌细胞的胞浆Ca2+浓度([Ca2+]i)变化及钙瞬变动力学参数的影响.方法游离单个大鼠心室肌细胞,Fluo-3/AM负载,电刺激诱发心室肌细胞钙瞬变,定量测定心室肌细胞内Ca2+浓度变化,异丙肾上腺素(isoproterenol, ISO)100nmol·L-1激动β-受体,观察CPU 228 1 μmol·L-1对钙瞬变动力学参数、[Ca2+]i及钙负荷水平的影响.结果CPU 228 1 μmol·L-1对大鼠心室肌细胞[Ca2+]i的影响不明显(P>0.05);ISO 100 nmol·L-1显著升高大鼠心室肌细胞[Ca2+]i和细胞内钙负荷水平,缩短钙瞬变时程,并且增加钙瞬变的消除速率.CPU 228 1 μmol·L-1显著抑制ISO的上述作用.结论在β-受体激动情况下,CPU 228可以降低心肌细胞[Ca2+]i,使ISO改变的钙瞬变动力学参数恢复到正常水平. 相似文献
43.
PURPOSE: There is controversy between clinicians and statisticians on the appropriateness of the number needed to treat (NNT) as a summary statistic to report the effectiveness of a treatment. We examine the two viewpoints and make proposals concerning the reporting of clinical trial results. METHODS: In the context of antiepileptic treatments, we explain the two different viewpoints and illustrate the use of the odds ratio, relative risk, absolute difference, and NNT on the results of randomized clinical trials with topiramate (TPM). Special attention is paid to the use of these summary statistics in meta-analyses. Here, the NNT is the expected number of patients one would need to treat to achieve a single occurrence of a specified good outcome (e.g., 50% reduction in seizure rate) in comparison to no (or placebo) treatment. RESULTS: Although the NNT is readily interpretable in some instances, it exhibits undesirable statistical behavior in other cases. In particular, confidence intervals for the NNT may split into two intervals and extend to positive and negative infinity when treatment efficacy is not clearly established by the data. Meta-analyses cannot be sensibly conducted directly on the NNT scale. CONCLUSIONS: Although other measures, such as the odds ratio, have been more commonly used in the context of meta-analyses, clinicians prefer the NNT because it gives them a clearer clinical interpretation of the effectiveness of a (new) treatment. On the other hand, statisticians do not recognize the value of the NNT, as it has undesirable statistical properties. Some reconciliation between the two views could be achieved when the clinicians acknowledge the weak aspects of the NNT and when statisticians realize that statistical appropriateness is not the same as clinical relevance. It is suggested that the NNT be used as a secondary reporting tool not on an equal footing with the classic scales. 相似文献
44.
乌贼墨对小鼠脾细胞和巨噬细胞NO生成及 IFN-γ分泌水平的影响 总被引:1,自引:0,他引:1
目的:探讨乌贼墨对脾细胞和巨噬细胞NO生成及IFN-γ分泌的影响。方法:用Griess法和ELISA法分别检测了经乌贼墨灌胃处理后小鼠脾细胞和腹腔巨噬细胞培养上清中NO和IFN-γ的水平的变化。结果:乌贼墨灌胃处理小鼠后的第4、6天脾细胞及腹腔巨噬细胞(Mφ)可产生较高水平的NO;脾细胞可产生较高水平的IFN-γ,并且小鼠脾细胞NO的产生水平与IFN-γ产生水平呈正相关(r=0.98);用LPS和L-NMMA(NO抑制剂)分别同乌贼墨灌胃第6d小鼠的脾细胞一起培养,结果显示LPS可协同IFN-γ促NO水平升高。L-NMMA可抑制小鼠脾细胞的NO生成。结论:乌贼墨可促进巨噬细胞NO生成;脾细胞NO的产生与IFN-γ分泌水平呈正相关。 相似文献
45.
食品级番茄红素对小鼠的免疫调节功能 总被引:4,自引:0,他引:4
目的研究番茄红素对免疫系统的调节作用。方法实验小鼠随机分成3组:对照组、低剂量组(10mg/kg)、高剂量组(20mg/kg)。低剂量组、高剂量组分别用色拉油稀释的番茄红素灌胃,对照组用色拉油灌胃。30天后检测小鼠的脾淋巴细胞增殖程度、NK细胞的杀伤活性、迟发性变态反应的程度、巨噬细胞吞噬功能。结果与对照组比较,高剂量组能显著增强脾淋巴细胞的增殖能力,提高自然杀伤细胞的活性和巨噬细胞吞噬功能,增强小鼠的足跖肿胀度(P〈0.05)。除增殖反应外,低剂量组其他指标与对照组比较,差异均无显著性。结论番茄红素具有增强小鼠免疫调节的功能。 相似文献
46.
47.
目的:探讨4种口服给药方案治疗良性前列腺增生(BPH)所产生的成本-效果比.方法:选择我院门诊轻中度良性前列腺增生患者168例,随机分为4组,分别给予非那雄胺(A纽)、坦索罗辛(B组)、坦索罗辛多沙唑嗪加非那雄胺(C组)、普适泰(D组),运用药物经济学方法进行分析.结果:在成本相当的前提下,C组方案有效率最高.结论:坦索罗辛多沙唑嗪 非那雄胺治疗BPH不仅疗效好,可降低患者需要手术的危险性,而且可降低急性尿潴留发生率. 相似文献
48.
目的 采用氢核磁共振(1H-NMR)代谢组学技术对不同生产厂家的阿胶酸水解成分进行差异性比较。方法 对5个不同生产厂家的阿胶进行酸水解,然后进行1H-NMR分析。对所得的1H-NMR图谱进行化学成分归属指认,并结合相关软件进行多元统计分析,找出差异性化学成分。结果 从阿胶1H-NMR谱中指认出17种化学成分;通过对A、C、D、E厂家生产的阿胶与B厂家生产的阿胶进行比较分析,找出了相应的差异性成分,主要包括异亮氨酸、羟脯氨酸、精氨酸、亮氨酸、苯丙氨酸、缬氨酸、赖氨酸和乙酰丙酸等。结论 1H-NMR代谢组学方法可用于不同厂家阿胶化学成分差异性的分析,为阿胶的质量控制提供新方法和新思路。 相似文献
49.
Asmau Iyabo Balogun Eswaran Padmanabhan Firas Ayad Abdulkareem Haylay Tsegab Gebretsadik Cecilia Devi Wilfred Hassan Soleimani Prasanna Mohan Viswanathan Boon Siong Wee Jemilat Yetunde Yusuf 《Materials》2022,15(23)
A novel technique was employed to optimize the CO2 sorption performance of spent shale at elevated pressure–temperature (PT) conditions. Four samples of spent shale prepared from the pyrolysis of oil shale under an anoxic condition were further modified with diethylenetriamine (DETA) and ethylenediamine (EDA) through the impregnation technique to investigate the variations in their physicochemical characteristics and sorption performance. The textural and structural properties of the DETA- and EDA- modified samples revealed a decrease in the surface area from tens of m2/g to a unit of m2/g due to the amine group dispersing into the available pores, but the pore sizes drastically increased to macropores and led to the creation of micropores. The N–H and C–N bonds of amine noticed on the modified samples exhibit remarkable affinity for CO2 sequestration and are confirmed to be thermally stable at higher temperatures by thermogravimetric (TG) analysis. Furthermore, the maximum sorption capacity of the spent shale increased by about 100% with the DETA modification, and the equilibrium isotherm analyses confirmed the sorption performance to support heterogenous sorption in conjunction with both monolayer and multilayer coverage since they agreed with the Sips, Toth, Langmuir, and Freundlich models. The sorption kinetics confirm that the sorption process is not limited to diffusion, and both physisorption and chemisorption have also occurred. Furthermore, the heat of enthalpy reveals an endothermic reaction observed between the CO2 and amine-modified samples as a result of the chemical bond, which will require more energy to break down. This investigation reveals that optimization of spent shale with amine functional groups can enhance its sorption behavior and the amine-modified spent shale can be a promising sorbent for CO2 sequestration from impure steams of the natural gas. 相似文献
50.
目的探讨醛糖还原酶(AR)基因5’端(AC)n多态性与2型糖尿病肾病的关系。方法采用聚合酶链反应(PCR)、聚丙烯酰胺凝胶电泳及银染色技术分析了139例2型糖尿病病人(早期糖尿病肾病组61例,非糖尿病肾病组78例)和63例正常对照者AR基因5’端(AC)n的多态性。结果早期糖尿病肾病组Z-2等位基因频率高于非糖尿病肾病组和正常对照组(x^2=6.88、10.51,P〈0.01);含Z~2等位基因的基因型频率也高于非糖尿病肾病组和正常对照组(X^2=4.95、8.15,P〈0.05、0.01)。结论AR基因Z-2等位基因与青岛地区汉族2型糖尿病病人糖尿病肾病的发生发展有关。 相似文献