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201.
A cyanogen bromide fragmentation reaction of 3 hr in sodium dodecyl sulfate gel slices was used for the degradation of the toxins coded by the three cryIA genes from Bacillus thuringiensis kurstaki. Peptide patterns diagnostic for each toxin gene product were observed. Treatment longer than 3 hr led to the weakening and disappearance of protein bands. In 9 out of 16 wild B. thuringiensis strains tested, it was determined that only one of the cryIA genes was being expressed; in 6 strains, one to two genes were identified, with the presence of an additional gene possible and masked because of the overlap of peptide bands; in one strain none of the genes was expressed.  相似文献   
202.
Arginine vasotocin (AVT) is a neurotransmitter in the amphibian central nervous system and is released from the neurohypophysis in the regulation of hydromineral balance and other homeostatic functions. Many amphibians experience drastic changes in habitat with respect to water availability during their transformation from aquatic larvae to terrestrial adults. To examine whether metamorphosis is accompanied by a reorganization of central vasotocinergic neurons, the developmental organization of vasotocin neurons and nerve fibers was studied with immunocytochemistry in the brains of bullfrogs (Rana catesbeiana) and woodfrogs (R. sylvatica). In bullfrogs, early limb-bud-stage tadpoles had AVT-immunoreactive neurons and nerve fibers in the lateral septal nucleus, amygdala, preoptic hypothalamus, suprachiasmatic nucleus, and posterodorsal tegmentum. Woodfrog larvae showed similar patterns of hypothalamic AVT immunoreactivity, although neuronal staining in the amygdala did not appear until metamorphic climax, and never appeared in septal neurons or in the posterodorsal tegmentum. Whereas the highly terrestrialR. sylvatica adults must adapt to an adult habitat with prolonged periods of dehydration,R. catesbeiana adults remain semiaquatic and, as such, need not develop extreme mechanisms for water retention. Nonetheless, vasotocinergic pathways showed developmental similarities in the two species. The early appearance of AVT innervation in bothRana suggests that AVT has neuroregulatory functions well before metamorphosis.  相似文献   
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The metabolic effects of combined cyproterone acetate (50 mg) and percutaneous 17 beta oestradiol were studied during one year in 61 patients admitted for hyperandrogenia. Before treatment and at 6 and 12 months the following tests were performed: oral glucose tolerance test (OGTT) with insulinemia dosage, determination of total cholesterol, LDL, VLDL and HDL fractions, triglycerids, A1 and B apoproteins, liver function tests: bilirubinemia, alkaline phosphatases, transaminases and gamma glutamyl transferases. The patients' mean age was 27.0 +/- 6.8 years, the body mass index was 22.4 +/- 3.5 kg/m2. After one year of treatment the body mass index was not modified. Blood glucose slightly increased during OGTT; at 6 months this was significant at +30 minutes, at 12 months at +30, +60 and +90 minutes (P less than 0.05). There was no variation in insulinemia during OGTT. Total cholesterol decreased significantly at 6 and 12 months (P less than 0.001), this was associated with a decrease in HDL cholesterol, but without modification of the LDL + VLDL/HDL ratio. Decrease in HDL cholesterol was associated with a significant decrease in A1 apoproteins. No change in triglycerids and in liver function tests was observed at either date. In conclusion the metabolic effects of this association are described. These effects are minimal compared to those observed with cyproterone acetate and ethinyl oestradiol association in the literature. However, attention should be drawn to the possibility of glucose intolerance and decrease in HDL cholesterol and A1 apoproteins.  相似文献   
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