Showing papers on "Phosphotungstic acid published in 1979"

Electrochromic effects in solid phosphotungstic acid and phosphomolybdic acid

Abstract: The electrochromic performance of all solid‐state cells employing phosphotungstic acid and phosphomolybdic acid is reported. These cells employ SnO2 as the viewing electrode and graphite as the back electrode. Diffuse reflectivity changes of ∼50% are readily achieved in ∼10 msec. The cells, in the bleached state, can be made white to red, and become black in the colored state.

Ultracytochemistry of the cell membrane ii. the application of phosphotungstic acid staining to microvillus membranes of the cat small intestine

Abstract: As an extension of our ultracytochemical studies on the cell membrane, phosphotungstic acid (PTA) staining dissolved in various media was applied to the microvillus membranes of the cat small intestine. The staining was performed on ultrathin epon sections of fixed specimens. In many cases oxidation or bleaching of epon sections by performic acid (PF), hydrogen peroxide (PO) or periodic acid (PA) was done prior to the PTA staining.In general, the PFP (PTA dissolved in ddw or HCl) method, the POP (PTA dissolved in ddw or HCl) and the PAP (PTA dissolved in chromic acid) gave good stainability of epon sections. However, among these three methods the most reproducible results were obtained by the PFP method.The PFP reaction was positive in the glycocalyx, the apical and lateral membranes, apical vesicles, the maturing face of the Golgi complex and lysosomes of the absorptive epithelia and the goblet cells, mucigen granules in the goblet cells, granules of basal granulated cells and capillary endothelia, reticular and collagen fibrils and the basement lamina. It was of great interest to find an electron density spanning the plasma membrane in addition to the unit membrane-like structure.In order to elucidate the chemical nature of the PFP positive substances spanning the plasma membrane the PFP reaction was performed on specimens fixed in various fixatives, digested by various enzymes or extracted in an organic solvent, and on pure model samples. The data obtained thus far seem to indicate that the electron density spanning the plasma membrane observed in specimens stained by the PFP method is due to phospholipids and/or glycolipids in the membrane.It may also be stressed that the PAP, POP, or PFP reactions in general, and in particular the PFP reaction because of its high reproducibility, are extremely useful as conventional substitutes for the periodic acid-Schiff (PAS) -type reaction under the electron microscope, and can be performed quite easily on epon sections.

Serum uric acid.

Abstract: Data from the 1977 College of American Pathologists (CAP) Comprehensive Chemistry Survey and other programs have been analyzed in an interlaboratory comparison of the measurements of serum uric acid. The majority of clinical laboratories utilize some form of phosphotungstic acid (PTA) oxidation-reduction technic for the measurement of uric acid. Methods based on uricase are most often performed on some automated device. In this Survey, in which specimens containing minimal potential interfering compounds were used, there are no significant differences in the results obtained by phosphotungstic acid and uricase methods.

Staining of isolated rabbit neurons and neuroglial clumps.

Abstract: Isolated rabbit neurons stained just as intensely as neuroglial clumps did with Mallory's phosphotungstic acid haematoxylin, Weil and Davenport's, Marsland, Glees and Erikson's and with Gallyas's silver stain.