Rabbit design

We now had acceptable rabbits for the short-term (polyethylene) and long-term (aluminum) irradiations. Since the internal volume of this rabbit design was cooled by primary cooling water flowing through the rabbit, samples were protected by encapsulation in polyethylene and quartz vials for the short- and long-term irradiations, respectively. 

Scott, D., Status of the Pneumatic Rabbit Design in the High Flux Pile, ORNL CF-48-6-134, June 9, 1948. 

Several antiinflammatory compounds have been formulated in lactide/ glycolide polymers (107-111). Methylprednisolone microspheres based on an 85 15 DL-lactide/glycolide copolymer were developed for intra-articulate administration (111). The microspheres, prepared by a solvent evaporation procedure, are 5—20 jam in diameter and are designed to release low levels of the steroid over a extended period in the joint. Controlled experiments in rabbits with induced arthritis showed that the microspheres afforded an antiinflammatory response for up to 5 months following a single injection. 

Mineral Oil Hydraulic Fluids. No human studies examining dermal end points were located. In animals, no information on dermal effects following inhalation or oral exposure were located. A number of mineral oil hydraulic fluids have been tested for acute dermal toxicity in rabbits. Signs of skin irritation have been observed following application of a naphthenic petroleum-based hydraulic fluid designated as MIL-H-5606... 

Sugg and Hehre43 also obtained precipitin reactions with dextran or with sterile filtrates of sucrose broth cultures of L. mesenteroides (designated for convenience strain A) and not only anti-Leuconostoc sera, but also pneumococcus Types II, XII and XX antisera. Leuconostoc organisms cultured on D-glucose broth neither stimulated the production of dextran-reactive antibodies in rabbits, nor absorbed dextran-reactive antibodies from sera, as did organisms cultured on sucrose. Absorption with the homologous bacteria (Leuconostoc, pneumococcus Types II,... 

Acute inhalation lethality data for the rat, mouse, and rabbit for exposure times of 10 s to 12 h were located. A single inhalation study with the dog did not give an exposure duration. The data are summarized in Table 5-4. Data from studies with nonlethal concentrations are summarized in Table 5-5. Barcroft (1931) reported LC50 values and times to death for eight species of animals, the times to death at a constant concentration. Due to experimental design constraints, the LC50 values are not reported here, but relevant data are discussed in the section on relative species sensitivity (Section 4.4.1). 

Other modifications of the non-constrained PAF framework have led Hoffmann La Roche s group to develop a further series of antagonistic compounds. The two closely related tetramethylene derivatives, both designated Ro 19-3704 (4c), are the most efficient and inhibit PAF-induced rabbit platelet aggregation with an IC50 value of 3.0 and 0.4 /iM respectively [113]. 

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