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M H ROSS

Publications and source records attributed to M H ROSS.

11 recordsLinked to original sources
PubMed1962

Inheritance of DDT-resistance in a European strain of Blattella germanica (L.).

A strain of Blattella germanica has recently been obtained from Europe which has proved to be highly resistant to DDT. This paper reports on genetical studies designed to show the mechanism of inheritance of the trait. Various crosses involving this strain and strains susceptible to DDT or possessing genetic markers were made. Progeny were tested for resistance to DDT and were examined for markers. The results show that DDT resistance is inherited as a simple Mendelian trait, with the hybrid being incompletely susceptible. Resistance appears to be on the same linkage group as "balloon-wing", but is independent of "orange-body".

Animals↗
PubMed1958

Studies on the generalized Shwartzman reaction. VIII. The appearance, by electron microscopy, of intravascular fibrinoid in the glomerular capillaries during the reaction.

The intravascular fibrinoid which is deposited in glomerular capillaries of the rabbit during the generalized Shwartzman reaction has been studied with the aid of the electron microscope. In one group of animals the reaction was produced by two intravenous injections of Escherichia coli lipopolysaccharide endotoxin, spaced 24 hours apart. In another, a single dose of endotoxin was followed, 1 hour later, by intravenous liquoid (sodium polyanethol sulfonate). The appearance of fibrinoid was the same in the two groups. Initially, fibrinoid deposition occurred on the irregular, swollen surfaces of the endothelial cells within the capillary lumen. Subsequently, the fibrinoid mass increased to such proportions that the capillary lumen was completely occluded. Fibrinoid was found to be composed of unbranched fibrils, having a diameter of 200-300 angstroms and an axial repeating structure of 120 A. The basement membrane (lamina densa) underwent no change in appearance during the time when fibrinoid was being laid down. Balloon-like vesicles were consistently encountered in endothelial cells of glomerular capillaries after two doses of endotoxin, and also in animals given one injection of endotoxin followed by liquoid. The possible significance of the observations are discussed. It is suggested that they are compatible with the hypothesis, proposed earlier, that intravascular fibrinoid, in the generalized Shwartzman reaction, is derived from fibrinogen.

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