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261.
The scent apparatus of male Eldana saccharina is a glandular complex on the costal area of the forewing. It consists of two parts; glandular complex 1 is composed of five kinds of cells (epidermal cells, scale cells, glandular cells, supporting cells, duct cells); glandular complex 2 also shows five types of cells (epidermal cells, scale cells, glandular cells, duct cells, trichogen cells). The secretory products of the two parts are discharged into separate ducts which converge before opening onto the lower side of the wing. The male also has two prominent hair-pencils borne on the coremata and large secretory trichogen cells on the genital valves. Each of these exocrine gland components plays an important part in formation of the chemically complex pheromones utilized in the precopulatory behavior of the male.  相似文献   
262.
OM-89 (Subreum) is anE. coli extract used for oral administration in the treatment of rheumatoid arthritis. It contains bacterial heat shock proteins, namely hsp60 and hsp70, which were shown to be major immunogenic constitutents of the drug. Immunity to bacterial heat-shock antigens was shown to be a means of immunomodulation of (experimental) autoimmune disease and possibly inflammation in general. This was demonstrated for mycobacterial hsp60 respectively hsp70 in autoimmune disease models for arthritis, diabetes and encephalitis. Parallel to the effects displayed by immunisation with hsp, oral administration of hsp-containing OM-89 was found to modify autoimmune disease in a number of animal models, such as for arthritis, diabetes and SLE. In rats immunisation with OM-89 was found to lead to proliferative T cell responses to hsp60 and hsp70 of bothE. coli and mycobacterial origin. Conversely, immunisation with hsp antigens could induce T cell reactivity specific for OM-89. Given this and the autoimmune disease modulating properties of both hsp and OM-89 it is argued that OM-89 acts via the same mechanism as proposed for hsp: that peripheral tolerance is induced at the level of regulatory T cells with specificity for heat-shock proteins. This may constitute one mode of action for OM-89 as an arthritis suppressive oral drug in man.  相似文献   
263.
Unicellular dinoflagellate algae are among the best examples of organisms that exhibit biological clocks. This study examined the effect of light regime on rhythmicity of motility in the symbiotic dinoflagellate Symbiodinium sp., freshly isolated from the soft coral Heteroxenia fuscescens (Ehrenberg). Freshly isolated algal cells, placed under a 12-h L:12-h D cycle, exhibited motility with a diel rhythm. This motility occurred only during the period of illumination and lasted 8-9 h, with a peak at 2.5-4 h after lights on. Algal cells placed in an inverted light regime inverted their motility pattern. The response to the L/D regime was very precise, and even a 1-h shift backward or forward affected initiation of motility and time of its maximal peak. When placed in either constant light or dark, algal motility ceased until the L/D cycle was restored. These findings suggest that the rhythm is entrained by light cues and is not due to an endogenous circadian rhythm. Further, we provide evidence that the presence of juvenile hosts does not affect the algal motility pattern. These results offer the first evidence for the lack of impact by the host on rhythmicity of motility of free-living algal cells. The motility pattern found in freshly isolated algae may indicate the presence of light-induced diel rhythmicity in yet-to-be described free-living Symbiodinium.  相似文献   
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