体育科学实验研究中对照设置的常见问题及对策

在控制额外变量的前提下,探讨自变量取值的变化对因变量取值变化的影响是实验研究的主要逻辑所在。而自变量取值的变化常需要通过设置对照条件来实现。因此,设置有效的对照是实验研究的重要环节。本文分析了体育科学实验研究中对照设置的常见问题,并在此基础上提出了相应的解决对策。缺乏必要的对照会导致实验的内部效度受到严重制约,研究结论的可信度下降。对照不全导致多组之间的可比性变差,最终导致实验结果的解释性不强。对照过剩不仅不能为研究结果提供较好的参照,而且还会造成被试资源的浪费。空白对照设置难以排除安慰剂效应等无关因素影响,且常不符合伦理要求。因素内部对照水平设置不当会导致多组间可比性下降。自身前后对照不当导致犯Ⅰ型统计错误可能性增加。对照控制不严格导致实验结果难以排除表现偏差和检测偏差等的影响。最后建议体育科学研究者在设计实验时,需要根据实验内部效度可能受到的威胁设置有效的对照组,并进行必要的对照检查,进而为体育科学实践提供可信赖的证据。

新药临床试验方案设计的研究

目的研究新药临床试验设计方案。方法本文涉及临床试验设计中的研究目的、范围及对照药的剂量,以探讨试验设计的合理性。结果在众多的新药临床试验方案中发现,在研究目的、范围及对照药的剂量等方面存在很多问题,从而导致新药临床试验的失败,最终药品不能上市。为此本文通过案例为研究者及药品申办者提供了大量相关信息。结论试验设计是临床试验能否获得成功的关键之一。

The Effect of Mercury on Lipid Peroxidation and Its Relation with Vitamin （A, E） and Essential Elements in Dentals Serum

In the present study, the authors attempted to shed a light on the possible relationships between lipid per oxidation markers, serum malondialdehyde （MDA） with the effect of mercury exposure using serum samples obtained from 100 mercury exposed dentals due to their occupation. These dentals were divided into two groups according to their occupational period. The third group consists of healthy volunteers that were working outside the mercury factories as a control group. The present results showed that mercury levels increased with the increasing of their occupation period. The highest level was 5.7 μg/dl, compared to the control group which was 0.1 μg/dl., The level of MDA was elevated in the workers and the highest level was found to be 41.00 nmol/dL for workers with longest period compared to the control group 8.6 nmol/dL. Some serum antioxidants such as vitamin A, E and albumin were evaluated and were found to be lower in all workers compared to the control group. The present results showed that Mg levels increased with the increasing of their occupation period and were found to be lower in Zn, Se of all workers compared to the control group.