The importance of a constant hydrogen ion concentration of the arterial blood to normal tissue function has been greatly stressed within the past decade. The apparent dependency of tissue acidity on blood acidity coupled with the constancy of the arterial hydrogen ion concentration in the normal individual seemed to justify this emphasis. This constancy of hydrogen ion concentration of the arte...

1. It has been shown quantitatively that the degree of response of the hind limbs of tadpoles to the action of thyroxin is dependent upon the lengths of the limbs at the beginning of treatment. 2. Both the potency of the inducing substance and the rate of penetration of the substance into the animal might be involved in the effects of hydrogen ion concentration on induced development. 3. Change...

1. Pepsin in solution at 38 degrees C. is most stable at a hydrogen ion concentration of about 10(-5) (pH 5.0). 2. Increasing the hydrogen ion concentration above pH 5.0 causes a slow increase in the rate of destruction of pepsin. 3. Decreasing the hydrogen ion concentration below pH 5.0 causes a very rapid increase in the rate of destruction of the enzyme. 4. Neither the purity of the enzyme s...

One of the most striking peculiarities of enzyme action is the fact that the activity of the enzyme is limited to a definite range of acidity. If the solution is more or less acid than this the enzyme is practically inactive. SSrensen 1 showed that for a number of enzymes the determiuing factor was the hydrogen ion concentration and not the total acidity of the solution. In attempting to accoun...

1. Bromthymol blue added to rat liver mitochondria at concentrations in the range 0.4 to 4.0 mpmoles per mg of protein is tightly bound as indicated by centrifugation and washing of the mitochondria. 2. The absorbance of the dye is increased on adding Ca++ or Mn++ to the mitochondria in the absence of a permeant anion. The extent of increase is 0.03 cm-l for 167 PM Ca++ at 618 rnp for 0.5 mpmol...

This paper presents an application for measuring the concentration of hydrogen ion by using ion selective electrodes. By this research we hope to provide useful information and verify the feasibility of measuring the concentration of other ions in the same way for sensing sweat. In this research, a pH electrode is used to generate an electrical potential which reflects the concentration of hydr...

Howe and Hawk (1912) were the first to determine the exact hydrogen-ion concentration of human fjeces. They examined samples of fa}ces from three individuals and found that the reaction of the material examined by them was always alkaline, varying with the different subjects and conditions from pH 7.01 to 8.77. Nelson and Williams (1916) recorded that 29 of the 30 individuals examined by them p...

With the use of ‘4C-DMO (‘4C-5, 5dimethyl-2,3-oxazolidmnedione), a weak organic acid, we measured the intraerythrocytic hydrogen ion concentration in 16 acidotic and alkalotic patients. Whole blood pH, red cell 2,3diphosphoglycerate, hemoglobin, oxyhemoglobin, plasma pCO2, and plasma bicarbonate were measured simultaneously on heparinized arterial blood. The results show: (1) hydrogen Ion conce...

In concentration of hydrogen peroxide, first, the solution should be quite pure, and then, it concentrate with methods such as vacuum distillation and cooling crystallization, because impurities in the hydrogen peroxide solution in high concentrations are causing decomposition of this substance; that is very dangerous. The purpose of this article is separation of chromium and magne...