A new method was proposed to determine the nitrogen content of nitrocelluloses (NCs). It is based on the finding of a linear relationship between the nitrogen content and the molar ratio of nitrite-to-nitrate ions released after alkaline hydrolysis. Capillary electrophoresis was used to monitor the concentration of nitrite and nitrate ions. The influences of hydrolysis time and molar mass of NC...

The detection and assay of vitamin B-2 (riboflavin) was accomplished under aqueous conditions using sodium borate buffering at pH 7.52 conditions. The absorbance spectrum of riboflavin was determined at different pH values utilizing several buffers. The buffer at pH at 7.52 is followed by accurate and sensitive assay of riboflavin by spectrophotometer at 440 nm wavelength. Where indicated an or...

When immersed in water cells of hepatomas produced by p-dimethyl-aminoazobenzene (butter yellow) take in less water than liver cells from which they are derived and more rapidly undergo disintegration; cholangiomas produced by butter yellow undergo similar changes. As a result of the injury of the tumor cells by water the osmotic exchange, characteristic of the normal liver cells under the same...

The effect of 24-hours continuous somatostatin-14 infusion on the volume of the bile secretion and on the bile composition were studied in seven patients with malignant biliary obstruction who had transhepatic external biliary drainage. The bile acid composition was measured with high performance liquid chromatography (HPLC). Somatostatin infusion significantly reduced the daily bile loss from ...

The osmotic coefficient of aqueous solutions of cyclohexylsulfamic acid was determined by freezing point measurements up to the molality 0.65 mol kg-1. The osmotic coefficients were fitted to the Pitzer equation, and ion interaction parameters α1, β(0) and β(1) were evaluated. The mean ion activity coefficient of the solute was calculated, and the non-ideal behaviour of the system investigated ...

BACKGROUND Reductions in detrusor shortening velocity and detrusor contractility have been observed in association with aging. The reasons for these changes are unclear. METHODS We examined the isometric and isotonic responses of detrusor, taken from the bladder body, to adenosine 5'-triphosphate (ATP), noradrenaline (NA), serotonin, and acetylcholine (Ach) in vitro, using bladders from young...

To counter environmental threats to the water resources polluted by NH, which is common in wastewaters and agricultural runoff, adsorption using mesoporous functional materials represents a promising alternative to existing treatment methods. In this study, adsorption of NH ions from aqueous solutions was investigated on arene- and propylsulfonic acid functionalized SBA-15 mesoporous silica mat...

Fluorescently labeled myosin heads (S1) were added to muscle fibers and myofibrils at various concentrations. The orientation of the absorption dipole of the dye with respect to the axis of F-actin was calculated from polarization of fluorescence which was measured by a novel method from video images of muscle. In this method light emitted from muscle was split by a birefringent crystal into tw...

The thiobarbiturates differ from other barbiturates in having a sulfur atom in place of the carbonyl oxygen at the C-2 position. The drug 2-thiobarbituric acid was found to be sufficiently soluble in 95% ethanol and 5% water for highly sensitive detection and assay. Analytical samples, including standards, were studied at 320 nanometer wavelength with background absorbance of the solvent correc...