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991.
Larvae of the Angoumois grain moth readily established in refined diets moulded into pellets. A bioassay based on larval establishment, weight, and numbers of adults was used to determine the insect's major nutritional requirements. The results showed that test diets containing corn starch (49–64%), glycerol (15–19%), casein (9%), yeast (7·5%), and wheat germ (2·6%) permitted good establishment and normal development. No further improvements were obtained when diets were supplemented with a mineral or vitamin mixture, cholesterol, or ascorbic acid. It was concluded that yeast and wheat germ supplied the insect with adequate amounts of lipids, vitamins, and minerals. However, even the best diets lacked some undetermined growth promoting factor because larvae grew better in a natural product control diet. 相似文献
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Processes of development and structure of epithelial formations, localized in the connective tissue framework of the gingival mucous membrane have been studied. During the prenatal period of development they are presented as epithelial pearls of Serra, and after birth--as remnants of ++tooth-forming epithelium (RTE). They are remnants of sheaths of the destroyed pearls. The latter, like RTE in the gingival stroma, have a genetic connection with the epithelial islets of Malasser and can cause some diseases in the gingiva. 相似文献
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Tumor line specific immunity could be induced in chickens with the use of BCG or CP. Direct contact between bacteria and tumor cells was required for immunity induction, but succeeded only in animals which also had been previously injected with the same bacterial vaccine. While other methods such as iv injected live mitomycin treated tumor was capable of inducing immunity, only BCG or CP mediated immunity was capable of being adoptively transferred in the Winn assay. Bursectomized agamma-globulinemic chickens also produced strong transferable immunity. Crossreactivity between transplant lines was detectable upon rechallenge of immune donors but was not evident upon adoptive immunity transfer. Immunity was detectable in the spleen and in peripheral blood lymphocytes but could not be transferred by thymus cells. 相似文献