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791.
, , , and 1992. Cloning and partial nucleotide sequence of Schistosoma japonicum paramyosin: a potential vaccine candidate against schistosomiasis. International Journal for Parasitology 22: 1187–1191. Paramyosin from the blood fluke, Schistosoma mansoni, has shown promise as a vaccine candidate for schistosomiasis mansoni. Here we report the cloning and partial nucleotide sequence of a cDNA encoding paramyosin from the related human parasite, Schistosoma japonicum. Affinity purified antibodies to this clone recognized a S. japonicum antigen of molecular weight 97 kDa, equivalent to the reported size of S. mansoni paramyosin. Alignment of the cDNA sequence with that of S. mansoni paramyosin revealed 90% identity. Comparison of the predicted amino acid sequences revealed 95% identity. Although these two parasites differ in many characteristics, the substantial homology demonstrated here between S. mansoni and S. japonicum paramyosin could have important implications for the development of a S. japonicum vaccine.  相似文献   
792.
Mc Manus , Sister Mary Annunciata , R.S.M. (Mount Mercy Coll., Cedar Rapids, Iowa.) Laboratory cultivation of Clastoderma debaryanum. Amer. Jour. Bot. 48(10): 884–888. Illus. 1961.—Clastoderma debaryanum has been cultivated on laboratory media for the first time and its life cycle studied. Spores germinate to produce a single protoplast which may remain a myxamoeba or may become a swarm cell. The swarm cells fuse in pairs to form a zygote, which grows into a microscopic, spherical plasmodium. The plasmodium never develops a network of veins and shows only irregular streaming. At maturity each plasmodium gives rise to 1 sporangium. There is always a sphere of gelatinous material about 4/5 the distance up the stalk, which appears late in the development of the sporangium, and which dries to become a wrinkled enlargement. The peridium dehisces early, leaving only a few plates attached to some of the peripheral tips of the capillitial twigs, and a peridial collar. The solid capillitium branches from the tip of a very short columella.  相似文献   
793.
Myxomycete plasmodia of 4 types (other than Physarum polycephalum), namely, Didymium clavus, Hemitrichia vesparium, Stemonitis fusca, and Clastoderma debaryanum, were sectioned and studied by electron microscopy. Organelles of all species have been described. In general, they are similar in the various species studied and resemble those found in animal cells and the cells of some lower plants. Mitotic figures and centrioles were not observed. Fibrils of 3 types were found; they were most prominent in Clastoderma debaryanum.  相似文献   
794.
We examined the changes induced by daily treadmill exercise on body weights, plantaris muscle weights, plantaris protein concentrations, and L-leucine-4,5-3H incorporation into plantaris muscles of normal and castrated young male guinea pigs and of castrated animals receiving testosterone replacement therapy, and compared the testosterone-1,2-3H uptake by plantaris muscles of trained normal guinea pigs to that of untrained animals. Trained animals exhibited significantly lower body and muscle weights and greater labeled leucine incorporation into sarcoplasmic and myofibrillar proteins but did not show significant changes in protein concentrations or labeled testosterone uptake. The level of physical activity of the young animals studied appeared to be more important than gonadal endocrine function in altering protein metabolism and muscle and body weights. Because hypertrophy did not occur in the trained plantaris muscles, which had elevated rates of labeled leucine incorporation, it appears that the trained animals had a higher muscle protein turnover rate. It seems unlikely that testosterone plays an important role in these activity-related phenomena.  相似文献   
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