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Elaine R. Reynolds Eric A. Stauffer Laura Feeney Elizabeth Rojahn Benjamin Jacobs Carol McKeever 《Developmental neurobiology》2004,58(4):503-513
Drosophila bang‐sensitive (bs) mutants exhibit a stereotypic seizure and paralysis following exposure to mechanical shock. In a physiological preparation, seizures and failures corresponding to the defective behavior are observed in response to high frequency stimulation. The amplitude of the stimulus necessary to produce bs behavior, or seizure threshold, varies with bs mutant and its gene dosage. In many respects, the bs defects are similar to those observed in mammalian seizure disorders. Antiepileptic drugs (AEDs) were administered by feeding to easily shocked2 (eas2), a representative bs mutant. The mean recovery times of treated flies were examined in comparison to control cultures. Some of the drugs administered, including carbamazeprine, ethosuximide, and vigabactrin, had little or no effect on the bs behavior of eas2. Gabapentin, however, showed a reduction in mean recovery time with chronic drug exposure. Phenytoin also had a significant effect on the bs behavior of treated flies. There was a reduction of both mean recovery time and the percentage of flies that displayed bang‐sensitive behavior with both acute and chronic treatment. The adult giant fiber preparation was used to examine the effects of phenytoin physiologically. Treated eas2 flies showed changes in their response to normal stimulation as well as alterations in seizure threshold in response to high frequency stimulation. Gabapentin was also effective against two other bs mutants, bangsenseless1 and slamdanceiso7.8, at strain‐specific concentrations, while phenytoin also reduced bang‐sensitive behaviors in bangsenseless1 in a dose dependent manner. AEDs, therefore, can be used to dissect aspects of bs behavior and this model may be useful in understanding the underlying basis of seizure disorders. © 2003 Wiley Periodicals, Inc. J Neurobiol 58: 503–513, 2004 相似文献
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Gillian C. L. Lachelin H. A. Brant G. I. M. Swyer V. Little E. O. R. Reynolds 《BMJ (Clinical research ed.)》1972,1(5803):787-790
In a sextuplet pregnancy which followed gonadotrophin therapy the principal problems were threatened abortion, premature labour, and placental insufficiency. Delivery was by caesarean section soon after the onset of labour at 32 weeks. The five liveborn babies thrived. The sixth was a macerated stillbirth. 相似文献
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Erythropoiesis and granulopoiesis in the West Indian manatee, Trichechus manatus (Mammalia: Sirenia)
The West Indian manatee, Trichechus manatus, has amedullary, pachyostotic long bones. Since marrow cavities of the long bones typically are the locations of hemopoiesis in adult mammals, the manatee has evolved an alternative primary site of hemopoiesis. Histological examinations of spleens, livers, kidneys, and vertebral bodies indicate that the last-named location is the main site of erythropoiesis and granulopoiesis in T. manatus. This conclusion is based on the presence in the vertebrae of bone-marrow-containing diagnostic cell types including erythroblasts, megakaryocytes, and myelocytes, which are the precursor cells of erythrocytes, platelets, and granular leukocytes, respectively. No developing lymphocytes were found, so that the location of lymphopoiesis remains unknown. 相似文献
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Polypeptide components of an excitable plasma membrane 总被引:4,自引:0,他引:4
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Experiments were performed on four cats to characterize fasting gastric and small bowel motility and to assess the role of extrinsic vagal innervation in the control of that motor activity. A multilumen manometry tube was positioned to record pressure changes from the proximal small bowel and stomach. Transient vagal nerve blockade was accomplished by cooling the cervical vagosympathetic nerve trunks, previously isolated in skin loops on each side of the neck. Two characteristic patterns of basal activity were documented in the stomach: (i) regular phasic contractions of variable amplitude in the body of the stomach; and (ii) infrequent, irregular contractions of high amplitude in the distal antrum. In the duodenum, two predominant activity patterns were noted: (i) periods of continuous irregular activity; and (ii) irregular clusters of contractions separated by quiescent intervals. No typical migrating motor complex activity was seen in the basal gastric or small bowel recordings. Bilateral vagal blockade did not consistently change the general pattern of gastric or small bowel activity, but did appear to reduce gastric contractile activity, as measured by motility indices. We conclude that extrinsic vagal innervation does not play a major role in the control of fasting feline gastric and duodenal motility. 相似文献
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