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91.
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An easy, reproducible and fast procedure to isolate DNA from cotton leaves is described. The addition of 0.5 M glucose in the extraction buffer avoids browning by polyphenolic compounds and improves the quality of DNA for molecular analysis. The DNA yield ranged between 150–400 mg per gram of fresh tissue. The DNA was suitable for digestion by restriction enzymes and amplificatiion by Taq DNA polymerase.  相似文献   
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Intrastriatal corticotrophin-releasing hormone (CRH) was shown to induce a decrease in the plasma tectosterone concentration. Besides, the 6-OHDA pre-treatment completely prevented the suppression of plasma testosterone in response to intrastriatal CRH administration. The findings suggest that the striatum is involved in the extrahypothalamic regulation of the gonadal endocrine function.  相似文献   
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The development of the fin and limb buds involves a balance of centrifugal (active) and centripetal (passive) mechanical forces, the first of which acts to move the walls of these structures away from each other and the second of which holds them together. When the volume of the mesodermal core increases, the generated force meets with the resistance of the basal membrane, and as a result, the limb bud has a tendency to acquire a cylindrical shape. Collagen fibers, individual mesenchymal cells, and their groups hold together the dorsal and the ventral wall of the limb bud, prevent the movement of these walls away from each other, and in this way direct bud growth along the proximodistal and the anteroposterior axes. The balance of the forces which stretch the ectodermal layer and those which constrain it has also been observed in the development of other body parts.  相似文献   
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A rational attempt to prepare FmocHis(piTrt)OH regiospecifically gave in fact the well-known tau-trityl isomer, and experiments with model systems indicate that the prospects for access to pi-trityl histidine derivatives, which would be of great value for the racemization-free synthesis of histidine-containing peptides, are poor.  相似文献   
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Increasing evidence suggests that apolipoprotein D (apoD) could play a major role in mediating neuronal degeneration and regeneration in the CNS and the PNS. To investigate further the temporal pattern of apoD expression after experimental traumatic brain injury in the rat, male Sprague-Dawley rats were subjected to unilateral cortical impact injury. The animals were killed and examined for apoD mRNA and protein expression and for immunohistological analysis at intervals from 15 min to 14 days after injury. Increased apoD mRNA and protein levels were seen in the cortex and hippocampus ipsilateral to the injury site from 48 h to 14 days after the trauma. Immunohistological investigation demonstrated a differential pattern of apoD expression in the cortex and hippocampus, respectively: Increased apoD immunoreactivity in glial cells was detected from 2 to 3 days after the injury in cortex and hippocampus. In contrast, increased expression of apoD was seen in cortical and hippocampal neurons at later time points following impact injury. Concurrent histopathological examination using hematoxylin and eosin demonstrated dark, shrunken neurons in the cortex ipsilateral to the injury site. In contrast, no evidence of cell death was observed in the hippocampus ipsilateral to the injury site up to 14 days after the trauma. No evidence of increased apoD mRNA or protein expression or neuronal pathology by hematoxylin and eosin staining was detected in the contralateral cortex and hippocampus. Our results reveal induction of apoD expression in the cortex and hippocampus following traumatic brain injury in the rat. Our data also suggest that increased apoD expression may play an important role in cortical neuronal degeneration after brain injury in vivo. However, increased expression of apoD in the hippocampus may not necessarily be indicative of neuronal death.  相似文献   
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