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Biomedical subjects

S W Clark

Publications and source records attributed to S W Clark.

27 records · Page 2Linked to original sources
PubMed1977

Regulation of purine metabolism: a comparative study of the kinetic properties of adenylosuccinate synthetases from various sources.

1. Adenylosuccinate synthetase has been partially purified from rat liver, fetal rat liver, Novikoff ascites cells, Walker carcinoma 256 solid tumors, chicken liver and muscle, rabbit muscle and pig brain. 2. Considerable differences exist in Michaelis constants among the various species and the changes possibly reflect differences in regulation. 3. The kinetic properties of the enzyme are generally consistent with proposed metabolic roles in various tissues.

Adenylosuccinate Synthase↗
PubMed1975

Synthesis and use of affinity-labeling steroids for interceptive purposes.

Synthesis of 17 beta-bromoacetoxy-19-nortestosterone was carried out by reaction of 19-nortestosterone with bromoacetic acid in the presence of dicyclohexycarbodiimide. The steroid was capable of alkylating cysteine, methionine, and histidine under physiologic conditions, indicating its potential as an affinity-labeling steroid. 17beta-Bromoacetoxy-19-nortestosterone interrupted postimplantation pregnancy in the rat when administered into the lumen of the uterus at low doses or subcutaneously at higher doses. Exogenous gonadotropins or steroids in dosages sufficient to maintain pregnancy do not prevent the interceptive action of this steroid. Animals whose first pregnancies were interrupted by this steroid had a subsequent normal pregnancy. The mode of action may be via covalent bonding to the progesterone receptor resulting in exclusion of endogenous progesterone.

Abortifacient Agents↗
PubMedDate not supplied

Investigating reading disabilities using the rauding diagnostic system.

Should a measure of intelligence be replaced by a measure of listening in discrepancy definitions of reading disability? This question was answered using a newly developed diagnostic system, which is based on "rauding" theory and a causal model of reading achievement. In Study 1, diagnostic results were analyzed from 122 students in Grades 3 through 7 who took, via computer, a battery of tests called the computer Assisted Reading Diagnosis (CARD). In Study 2, 44 university students were given the CARD. In Study 3, the CARD was administered to 128 students in reading improvement classes at a suburban community college. From the results, it was concluded that the rauding diagnostic system consistently diagnoses disabilities in listening, decoding, and naming speed when they are theoretically needed to explain accuracy and rate disabilities of children and adults who are poor readers. It was recommended that (a) general intelligence, fluid intelligence, or IQ not be used to measure potential or to diagnose reading disabilities; (b) listening not be used to measure potential; (c) verbal knowledge aptitude, pronunciation aptitude, and cognitive speed aptitude be used to measure potential; and (d) the new rauding diagnostic system replace the system of diagnosing dyslexics, hyperlexics, and garden-variety poor readers.

Adolescent↗