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Biomedical subjects

R J Warren

Publications and source records attributed to R J Warren.

At least 55 records · Page 3Linked to original sources
PubMed1980

Laparotomy for staging of Hodgkins' disease.

Laparotomy was used for staging Hodgkin's disease in a selected group of 71 patients over a 9-year period at the Cancer Control Agency of British Columbia. Operative results altered the staging in 30 patients and the treatment in 28 patients. Negative lymphangiograms were found to predict accurately the absence of abdominal lymph-node involvement. No investigation was as accurate as laparotomy in identifying subdiaphragmatic Hodgkin's disease. There were no operative deaths and the overall morbidity was 18%. The value of staging laparotomy depends on the adjustment of therapy to match the changes in staging made as a result of this procedure. Of specific advantage is the avoidance of unnecessary chemotherapy. Improved long-term survival as a result of staging laparotomy has yet to be proven.

Adolescent↗
PubMed1979

A modified blow-gun syringe for remote injection of captive wildlife.

A modified syringe capable of automatic injection and suitable for use with a blow-gun is described. The syringe has been used successfully with white-tailed deer (Odocoileus virginianus) under confined conditions. Desirable characteristics for blow-gun syringes are discussed.

Animals↗
PubMed1978

Quantitative determination of cephalexin in cephradine by NMR spectroscopy.

An NMR method to determine quantitatively the presence of cephalexin in cephradine was developed. The method is applicable to the chemical itself as well as to capsules and oral suspension formulations. The determination is based on the NMR signal arising from the five aromatic protons of the cephalexin molecule. Integration of this signal relative to a signal from cephradine provides the data necessary to determine the percentage of cephalexin present. The precision at the 2% cephalexin levels is +/- 0.18%. The time required to carry out a single analysis is about 10 min, and five analyses can be done in about 0.5 hr.

Capsules↗
PubMed1978

Quantitative determination of chlorpromazine. HCl in tablets, spansules, injectables, and bulk chemical by nuclear magnetic resonance spectroscopy.

A nuclear magnetic resonance (NMR) procedure is described for the quantitative analysis of chlorpromazine. HCl in bulk chemical as well as in final dosage forms--tablets, spansules, and injectables. The method is based on measurement of a characteristic signal of chlorpromazine relative to an internal standard. Three different internal standards are specified: Cyclohexane was selected because of the convenience and rapidity with which samples could be prepared for assay. Piperonal was used to verify the method and to show that precision and accuracy were not affected by the volatility of the cyclohexane. Tetramethylammonium bromide was used as an internal standard for Thorazine injectable. No interferences were found from stearates and other tablet excipients. The NMR procedure provides a simple, direct, and specific assay with a precision of +/- 1-2%.

Capsules↗
PubMed1977

An automated continuous-monitoring procedure for the determination of acid phosphatase activity in serum.

The method of Hillmann, in which hydrolysis of alpha-naphthyl phosphate by acid phosphatase is coupled to the formation of an alpha-naphthol-Fast Red TR azo-compound, has been adapted for use with the LKB Produkter AB 8600 reaction rate analyzer. Factors which affect the reproducibility of the method are described and its performance is shown to be superior to that of a manual phenyl-phosphate procedure.

Acid Phosphatase↗
PubMed1976

Quantitative NMR analysis of a four-component mixture of phenylglycine derivatives.

A rapid, accurate, and precise NMR analytical method for the analysis of phenylglycine, dihydrophenylglycine, tetrahydrophenylglycine, and cyclohexylglycine in combination with each other was developed. The method is based on the integration of the NMR signal characteristic of each component relative to the signal from tetramethylammonium bromide, which is added as an internal standard. No prior separation of the four components is required.

Glycine↗
PubMed1975

Metabolism of D- and L-norgestrel in humans.

Levels of DL-norgestrel, D-norgestrel, L-norgestrel and norethisterone were measured in blood by radioimmunoassay after oral administration of the progestin to 3 healthy male subjects and the half-lives calculated. Half-lives for D-norgestrel were much lower than those of L-norgestrel and similar to those of norethisterone. Measurement of norgestrel in blood can therefore be misleading unless the biologically active D-isomer is estimated. Since there was no difference in half-lives between norgestrel and norethisterone the greater potency of the former is probably due to it more strongly binding to target organ receptors.

Half-Life↗