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AIM: To investigate the influence of Ginkgo biloba extract (EGb761) on c-jun expressions and motoneurons survival following root avulsion. METHODS: One hundred and eighty adult Sprague-Dawley female rats were randomly divided into control and EGb761 groups. Immediately after avulsion of C5-T1 nerve roots, the rats were injected ip with either 1 mL of EGb761 25 mg·kg-1·d-1 or the same volume of normal saline, and the treatment repeated everyday. At 4 h to 6 weeks following avulsion, the C7 spinal segments of all rats were collected and prepared for c-jun immunocytochemistry and neutral red stain. The numbers of c-jun positive and survival motoneurons were counted and compared between two groups at each time point. RESULTS: In control rats following avulsion, c-jun positive motoneurons appeared at 4 h, reached its maximum at 1 d and declined to 2 weeks. Avulsion-induced motoneurons death started at 2 weeks, climbed to its maximum at 4 weeks-6 weeks. In EGb761 treated rats, both numbers of c-jun positive and survival motoneurons were more than that in control group at each time point. CONCLUSION: EGb761 attenuates avulsion-induced motoneurons death, and this effect may be related to up-regulation of c-jun gene in avulsed motoneurons. 相似文献
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美洲鲥仔稚鱼脊柱及附肢骨骼系统的早期发育 总被引:1,自引:1,他引:1
使用软骨-硬骨双染色技术,描述了美洲鲥(Alosa sapidissima)仔稚鱼(1~51日龄)脊柱、胸鳍、尾鳍、背鳍等附肢骨骼的形态发育特征。结果显示,脊柱的发育开始于10日龄仔鱼尾部的髓弓、脉弓和尾下骨的出现,16日龄髓弓和脉弓延伸形成髓棘和脉棘,19日龄脊柱出现分节的硬骨环,23日龄所有椎体形成。各附鳍支鳍骨发育顺序先后依次为胸鳍、尾鳍、背鳍、臀鳍和腹鳍。胸鳍在2日龄时出现乌喙骨,13日龄形成软骨质的胸鳍支鳍骨,19日龄仔鱼肩带和上匙骨开始骨化;尾鳍的尾下骨最早出现在5日龄,12日龄尾鳍形成2枚尾上骨、1枚尾杆骨和6枚尾下骨,19日龄仔鱼尾椎和尾鳍率先开始骨化,直至23日龄尾鳍骨骼系统钙化完全。最终背鳍和臀鳍分别形成18和22根鳍条。美洲鲥骨骼发育研究对其早期发育功能趋向、环境优化及分类鉴定有重要作用。 相似文献
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Paulo Ricardo Dell'Armelina Rocha Andrea Bertuglia Elena Biasibetti Michela Bullone Alfonso Rosamilia Loretta Masoero Maria Teresa Capucchio 《Journal of Equine Veterinary Science》2014
Choroid plexus papilloma (CPP) is a rare, benign, intracranial neoplasm. The present report described a choroid plexus papilloma of the fourth ventricle with unusual proliferative reaction of ependymal/subependymal cells in a stallion. A single, soft neoformation, red-gray in color, with an irregular surface, resembling a cauliflower, expanding from the fourth ventricle to the cerebellar peduncles was observed. Microscopically, the neoformation was composed of a single layer of simple cuboidal to columnar epithelium with a well-vascularized papillary-arboriform pattern. Multifocal subependymal aggregates forming rosettes were observed near the mesencephalic aqueduct (MA). Glial-fibrillary-acidic-protein (GFAP) was markedly positive only in the neuropil adjacent to the proliferative areas of the MA. Ependymal/subependymal reactions secondary to CPP have never been described in equine or human neuropathology. The capabilities of ependymal cells to regenerate and eventually proliferate are controversial and unclear and, thus, require additional investigation to understand the adaptive mechanisms of this rare pathogenic condition. 相似文献
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Roslyn G. Machon B.V.Sc. M.V.Sc. M.S. Marc R. Raffe D.V.M. M.S. Elaine P. Robinson B.Vet.Med. M.V.Sc. 《Journal of Veterinary Emergency and Critical Care》1995,5(2):121-129
The caudla vena cava (CVA) was evaluated as an laternative site for the measurement of central venous pressure (CPV) in six healthy, sedated (ketamine 10 mg/km, midazolam 0.1 mg/kg, and atropine 0.04 mg/kg IM) cats. The CVC was cathererized via medial saphenous puncture, and estimates of CPV from this site compared to those obtained via a jugular catheter. Simulataneous CPV values were recorded electronically (mmgh), via calibrated pressure transducer positioned at the level of the manubrium in cats in lateral recumbency. Five readings, performed at 1 minute intervals, were collected from the jugular and CVC catheters at rest (baseline) and following a rapid fluid bolus. Twenty-four hours later, cats were resedated, baseline measurements repeated, and CVPs recorded following a rapid, 25% whole-blood volume bleed. CVP measurements from the jugular and CVC were statistically compared using repeated measures ANOVA (p<0.05). There were no significant differences between the two sites in the baseline and bleed trials. Significant defferences between jugular and CVC CVPs were noted at 1 and 2 minutes following the fluid bolus. It was concluded that CVC is an alternative site for measurement of CPV in sedated cats. 相似文献
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Marcelo Gómez DVM Larry Freeman DVM MS Jeryl Jones DVM PhD Otto Lanz DVM Pam Arnold 《Veterinary radiology & ultrasound》2004,45(1):29-37
Computed tomographic (CT) venography of the cervical vertebral canal was performed in six, clinically normal, adult mixed-breed dogs from 14 to 23 kg. After dogs were euthanized and saline perfused, a gelatin and iothalamate mixture was injected into the right external jugular vein. Contiguous, 4-mm-thick CT images were obtained with dogs in sternal recumbency. Dogs were kept in the same position as for the CT scan and frozen to approximately -8 degrees C. All post-contrast CT images were analyzed using similar bone window and level settings. Additional multiplanar reformatted dorsal images were obtained in all dogs. The frozen cadavers were sectioned through the cervical region extending from the occiput to T1 at approximately 8-mm intervals. The frozen sections were then compared with the CT images. The CT appearance of the normal cervical vertebral venous system was described and illustrated. Components such as the internal vertebral venous plexus, interarcuate veins, intervertebral veins, and vertebral veins were clearly identified on the CT images. 相似文献
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The vertebral heart score (VHS) measurement is commonly used to provide a more objective measurement of cardiomegaly in canines. However, several studies have shown significant breed variations from the value previously established by Buchanan and Bücheler (9.7 ± 0.5). This study describes VHS measurements in Pug, Pomeranian, Yorkshire Terrier, Dachshund, Bulldog, Shih Tzu, Lhasa Apso, and Boston Terrier dog breeds. Dogs with two or three view thoracic radiographs, no subjective radiographic evidence of cardiomegaly, and no physical examination findings of heart murmurs or gallop rhythms were included in the study. The Pug, Pomeranian, Bulldog, and Boston Terrier groups were found to have a VHS significantly greater than 9.7 ± 0.5 (P < 0.00001, P = 0.0014, P < 0.0001, P < 0.00001, respectively). Body condition score (BCS) was found to have a significant effect on the VHS of Lhasa Apso group. Anomalous vertebrae in the thoracic column were associated with a significant increase in VHS of the Bulldog (P = 0.028) and Boston Terrier (P = 0.0004) groups. Thoracic depth to width ratio did not have a significant effect on VHS. 相似文献