PubMed Health⌕ Search

Biomedical subjects

R D Gentry

Publications and source records attributed to R D Gentry.

4 recordsLinked to original sources
PubMed1983

Pharmacokinetic study of neomycin in calves following intravenous and intramuscular administration.

Neomycin sulfate was administered to calves by the intravenous and intramuscular routes. Serum drug levels were determined and the intravenous pharmacokinetic parameters derived using the Gauss-Newton nonlinear fitting algorithm and the two compartment open model. The kinetic parameters determined were as follows: zero time intercept, serum drug level 68.045 +/- 15.894 micrograms/mL, alpha slope intercept 37.666 +/- 13.874 micrograms/mL and beta slope intercept 30.379 +/- 12.638 micrograms/mL; equilibration rate (pool I and II) 0.081 +/- 9.064 min-1; elimination rate 0.004 +/- 0.001 min-1; half-time alpha 14.774 +/- 11.236 min, half-time beta 166.596 +/- 47.576 min; first order elimination constant 0.009 +/- 0.002 min+; transfer rate constants, central to peripheral, 0.032 +/- 0.026 min+ and peripheral to central 0.045 +/- 0.037 min-1; volume of central compartment 0.186 +/- 0.047 L/kg; volume of distribution 0.388 +/- 0.130 L/kg; body clearance 0.002 +/- 0.001 L/kg/min.

Animals↗
PubMed1981

Kinetic analysis of bovine factor VIII in the hemophilic dog.

Bovine factor VIII, which did not contain platelet aggregating factor activity, was infused into hemophilic dogs. Factor VIII procoagulant (VIII:C) levels in the dogs increased dramatically, then decreased in a biphasic manner. The half-life of the longest component was 3-7 hrs. The infusions were hemostatically effective and also caused a prolonged shortening of the activated partial thromboplastin time. These studies demonstrate that the platelet aggregating factor activity of bovine factor VIII is not essential for its maintenance in the circulation and that preparations lacking this activity may be clinically useful. When concentrates of partially purified factor VIII: C (essentially free of both platelet aggregating factor and factor VIII-related antigen) were infused, marked increases in VIII: C levels were also observed, but the half-life was significantly shorter (T1/2 of approximately 1 hr.).

Animals↗