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R Q Zhang

Publications and source records attributed to R Q Zhang.

17 recordsLinked to original sources
PubMed1989

In vivo measurement of total body magnesium and manganese in rats.

Mg and Mn are essential minerals in many biological processes. Thus knowledge of their absolute amounts and how those amounts may be altered is important. In the past the in vivo measurement of Mg in animals was limited by both the poor geometry of the counting system and the requirement for multiple counts of the animal over several hours. We have developed a neutron activation technique for the direct in vivo measurement of total body Mg and Mn in the rat. The counting system adapted for the technique has a response that is relatively invariant (+/- 2.5%) to differences in body size. A least-squares curve fitting technique was developed that requires only a single 5-min count of the animal. Our in vivo values for body Mg and Mn were in excellent agreement (+/- 2.0%) with the results of total carcass analysis using atomic absorption. Longitudinal changes in total body Mg and Mn were examined in vivo in two groups of animals maintained on test diets that contained different amounts of Mg.

Activation Analysis↗
PubMed1989

[Effect of cigarette-smoke tar on oxygenation activity of granulocytes detected by luminol- and lucigenin-enhanced chemiluminescence response of rabbit whole blood].

Both luminol- and lucigenin-dependent rabbit whole blood chemiluminescence showed a concentration-dependent inhibition response to cigarette-smoke tar of 0.26 to 2.6 mg/ml. Tar showed no cytotoxicity to granulocytes by Evans blue exclusion. It is suggested that oxygenation activity of granulocytes in smoker's blood could be depressed by tar, resulting in harmful effects on the host defense mechanism with increase of susceptibility to infection and incidence of tumorigenicity.

Acridines↗