Results 151 to 160 of about 13,488,800 (199)

Hormonal control of spermatogenesis in the cockroach, Periplaneta americana (L.)

Canadian Journal of Zoology, 1970
A surgical approach was made to the question of humoral regulation of testicular development. Neither the neurosecretory cells nor the prothoracic glands retarded or accelerated development of the testes. The corpora allata maintained the testes in a juvenile state by retarding their development.
W D, Blaine, S E, Dixon
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Excretion of uric acid in Periplaneta americana L.

Journal of Insect Physiology, 1961
Abstract In Periplaneta americana the Malpighian tubules do not take active part in the excretion of nitrogenous wastes, which are eliminated mainly through the ileum and colon. Large quantities of uric acid also accumulate in the fat body and are stored there. Similar observations on Aulacophora foveicollis and Forficula sp.
P.N. Srivastava, P.D. Gupta
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Location of the sex pheromone in the American cockroach,Periplaneta americana (L.)

Experientia, 1966
Das Vorkommen von Sexualpheromon wurde an dem Werbeverhalten von selektierten einzelnen Mannchen getestet. Das Pheromon kommt in larvalen und adulten Insekten beiderlei Geschlechts vor, wird aber von geschlechtsreifen Weibchen in grosseren Mengen produziert.
B, Stürckow, W G, Bodenstein
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Lysozyme Retention by Cockroach Periplaneta americana L.

Science, 1969
Blood from the cockroach Periplaneta americana usually does not react with a suspension of Micrococcus lysodeikticus . When lysozyme is added to the mixture it causes an immediate reduction in the optical density at 450 nanometers which is soon followed by a strong rise.
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Evidence for a myotropic effect of substance P in Periplaneta americana L

General and Comparative Endocrinology, 1989
It is shown that the isolated oviduct as well as the proctodeum of the cockroach Periplaneta americana are sensitive to substance P application. In contrast, the hyperneural muscle and the dilator muscle of the antennal heart were insensitive to this neuropeptide. The entire substance P amino acid sequence is necessary for the effects.
H, Penzlin, I, Wieduwilt, W, Hertel
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Experimentally induced tumours in Periplaneta americana L.

Journal of Insect Physiology, 1963
Abstract In experiments on the American cockroach the recurrens nerve was severed and the salivary ducts ligatured. The latter operation results in the development of tumours in the salivary acini, reservoir, and associated ducts. The tumours are characterized by rapid cell proliferation and accumulation of inclusion cyst material.
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The frontal ganglion of Periplaneta americana L. (insecta)

Cell and Tissue Research, 1978
The frontal ganglion, part of the stomatogastric nervous system, contains about 60 to 80 neurons, 25 to 30 micron in diameter. A well developed Golgi system, producing dense-core vesicles, lysosomes, multivesicular bodies and dense bodies are abundant. Glia elements are sparsely distributed.
J, Ude, M, Eckert, H, Penzlin
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Development of Periplaneta Americana (L.) Cell Cultures and their Infection with Enteroviruses

Journal of Medical Entomology, 1974
Dispersed embryonic cells of the cockroach Periplaneta americana (L.) were maintained in vitro for over 7 months in a new culture medium. These cultures were infected with echo virus type 6, poliovirus type 1, and Coxsackie virus type B5, and assayed for periods of 3 to 7 days to determine the susceptibility of the cockroach cells to viral infection ...
M, Klowden, B, Greenberg
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The mode of action of pyrethnxm on the cockroach, Periplaneta americana L

Annals of Applied Biology, 1943
Pyrethrin, the active principle of pyrethrum powder, is insoluble in water but is soluble in, the body fluid of the cockroach. It has a selective action on nerve ganglia, and the destruction of their cells is responsible for the death of the insect. Whereas pyrethrum, when used ‐either in the powdered form or in a fluid state mixed with kerosene and ...
D. N. Roy, S. M. Ghosh, R. N. Chopra
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The permeability of the cuticle of Periplaneta americana (L.) to malathion

Journal of Insect Physiology, 1963
Abstract The rate of entry of malathion through the cuticle of Periplaneta americana was found to deviate from the theoretical rate of diffusion. The deviation is particularly high at the beginning of penetration. It was found that the deviation was due largely to accumulation of malathion in the cuticle: a large amount of malathion was discovered in
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