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Biomedical subjects

R D Ward

Publications and source records attributed to R D Ward.

At least 127 records · Page 7Linked to original sources
PubMed1980

Lagochilascaris major in a raccoon.

A granulomatous mesenteric mass containing numerous adult Lagochilascaris major was found in a raccoon near Houston, Texas. This is the first report of a Lagochilascaris in a species other than the opossum in North America.

Animals↗
PubMed1978

Subunit size of enzymes and genetic heterozygosity in vertebrates.

There is a small but significant positive correlation between individual locus estimates of heterozygosity and subunit molecular weight in vertebrate dimeric enzymes. This correlation is smaller than that previously shown to exist for Drosophila dimers, and some possible reasons for this are explored. Data for vertebrate tetrameric enzymes are less extensive but appear to give similar trends to those shown by dimers. It is concluded that enzyme heterozygosity is influenced by both subunit size and quaternary structure.

Amphibians↗
PubMed1978

Some methods for membrane feeding of laboratory reared, neotropical sandflies (Diptera: Psychodidae).

A brief introduction to the history and applications of membrane feeding is given, together with its use to feed and infect sandflies with Leishmania. The present paper describes methods for feeding Lutzomyia longipalpis and Lu. flaviscutellata through membranes. Of the membranes tested, chick skins and bat wings gave the best results. Membranes stored at -20 degrees C for over a year were found to be less effective than fresh ones. Blood meals were maintained at temperatures between 24 degrees C and 37 degrees C and it is concluded that although temperatures as high as 37 degrees C are unnecessary for successful membrane feeding of sandflies, fewer flies feed in most instances at temperatures below 27 degrees C. The influence on feeding of individual skins, different lots of blood and the addition of leishmanial cultures to offered blood are discussed.

Animal Nutritional Physiological Phenomena↗
PubMed1977

Relationship between enzyme heterozygosity and quaternary structure.

The need for proteins to maintain particular quarternary structures constrains variability in amino acid sequence. Monomeric enzymes are then expected to be more variable than dimeric forms, which in turn are expected to be more variable than tetrameric forms. These predictions are confirmed by analysis of available data on enzyme variation. Theories relating enzyme heterozygosity to metabolic function are discussed in the light of these findings.

Amino Acid Sequence↗