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Biomedical subjects

G M Smith

Publications and source records attributed to G M Smith.

At least 253 records · Page 14Linked to original sources
PubMed1974

Proton magnetic resonance spectra of Rhodospirillum rubrum cytochrome c2.

Nuclear magnetic resonance spectra of ferro- and ferricytochrome C(2) from the facultative photoheterotroph, Rhodospirillum rubrum, obtained with a 220-MHz spectrometer, are presented. Assignments to protons of various important structural groups in contact with or near the prosthetic heme group are given. These include (a) in the ferro-form, methyl, cbeta and cgamma protons of the extraplanar ligand residue, methionine 91, and methyl protons of the residue leucine 32; and (b) corresponding protons in the ferri-form with the addition of methyl protons from the condensation of a heme vinyl group with cysteine 17, a single proton from the condensation involving cysteine 14, and protons from the ring methyls. These resonances are compared with those corresponding to the same groups in horse heart cytochrome c.

Chemical Phenomena↗
PubMed1971

Preparation and assay of urogastrone, an inhibitor of gastric acid secretion.

1. Urogastrone, an acid gastric secretion inhibitor extracted from human urine, was assayed in the anaesthetized rat by circulating through its stomach a succinic-propionic buffer and recording electrometrically the secretion of acid in response to carbachol, and inhibition of carbachol secretion by urogastrone.2. Quantitative assay procedures are described requiring the administration of only one or two doses of urogastrone to each rat.3. An extraction procedure for urogastrone is described based on the use of zeocarb, a cationic polystyrene resin.4. The most purified samples contained 40-80 times the amount/milligram which was just detectable by the assay method.

Animals↗
PubMed1970

The assay of gastrin using the perfused rat stomach.

1. A method is described for the bio-assay of gastric secretagogues using the perfused rat stomach in which the acid output can be readily and accurately quantified.2. This technique increases the sensitivity of the perfused rat stomach so that 10-20 ng of synthetic human gastrin I can be detected.3. It is possible to assay secretagogues, relative to a standard with fiducial limits of less than +/-30%.4. The use of this system is illustrated by assays comparing synthetic human gastrin I with pentagastrin, pure hog gastrin and gastrin added to plasma.

Analysis of Variance↗