8 resultados para mandibular nerve

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A nerve growth factor (NGF) was isolated from the venom of Chinese cobra (Naja naja ntr a) by ion exchange chromatography, gel filtration and fast protein liquid chromatography (FPLC). The N-terminal sequence of 22 amino acid residues was identical with other NGFs previously purified from the venom of the same genus. The NGF monomer molecular weight was estimated to be 13 500 by reducing SDS-PAGE and the isoelectric point was determined to be 7.2 by isoelectric focusing electrophoresis. NGF improved the epididymal sperm motility of male rats and increased the pregnancy rate and fetus number of mated female rats. The serum levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) of male rats administrated NGF + gossypol was lower than that of male rats administrated gossypol. Histological sections of testes and epididymides showed that NGF reduced the destructive effects of gossypol on rat testes. (C) 1999 Elsevier Science Inc. All rights reserved.

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In order to understand how mandibular structure differs among the Chinese cercopithecoids (Rhinopithecus, Trachypithecus and Macaca), particularly the uniqueness of the snub-nosed monkeys (Rhinopithecus), we analysed ten mandibular measurements by principal components analysis (PCA), and examined scaling patterns. The results provided by the PCA illustrated differences due to size among the cercopithecoids and the relationship between colobines (Trachypithecus and Rhinopithecus) and cercopithecines, in which macaques (Macaca) are included. Allometric analysis indicated that, biomechanically, there is not a marked difference between macaques and leaf-eating monkeys. This may be associated with the fact that both share some similar ecology and niches in south and southwest China. The snub-nosed monkeys exhibit a significantly more robust mandible, evident in the symphysis, corpus, condyle, and masticatory momentum arm. This supports the hypothesis, based on the study of dental structure, that Rhinopithecus is a unique group in Asian Old World monkeys (OWMs) and has developed some unique characteristics in order to adapt to the tough food available in the severe cold climate of the Plateaux of Qinghai-Tibet, Yun-Gui and Qingling in China.

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Recent field studies suggest that Macaca thibetana, a large endemic Chinese macaque, may be quite folivorous, distinguishing it from most other macaque species, which tend to be primarily frugivorous. To understand how this diet affects its masticatory system, we conducted a comparative morphometric study of mandibular dimensions. We took linear measurements from male and female mandibles of this species as well as four other macaques-M. fascicularis, M. nemestrina, M. arctoides, and M. assamensis-and four species of Presbytis-P. obscura, P. rubicunda, P. cristata, and P. phayrei-and subjected to them to a variety of analyses. Based on analyses of variances and discriminant analyses on each sex individually, the mandible of M. thibetana corresponds to expected patterns for folivorous primates with respect to its wide condyles and thick corpora: However, the height of the corpus and symphysis are lower, and the anteroposterior length of the condyle is longer than predicted for a folivore. In addition to interpretations specifically relating to M. thibetana, we also discuss the functional morphology of the other species in light of what is published about their diets.

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In order to clarify the degree to which mandibular variation among Chinese macaques results from functional adaptation and phylogenetic inertia, 13 mandibular variables were analyzed by bivariate and multivariate techniques. The results indicate, not surprisingly, that the main differences in the mandible are associated with size. The study further implies that the variation between species is not closely associated with differences in functional adaptation even though the dietary and related differences are large compared to the situation in other macaques. The great variety in diet and related factors among Chinese macaques may not have yet resulted in a significant variation in the mandible. This may be because their radiation in Asia, though involving considerably greater differences in habitat, climate, and so on, has occurred more recently than for other macaque species in Southeast Asia. Mandibular variation between these species, therefore, is likely to be more closely tied to their immediate prior phylogenetic history. For example, the two stump-tailed macaques are closely similar and are also closely similar to the Assam species. Function in the mandible in these species is quite different. The results, therefore, seem to support the hypothesis that these three macaque species should be placed in a single species-group (sinica) as proposed by Delson [1980], Pan [1998], and Pan et al. [1998]. (C) 2002 Wiley-Liss, Inc.

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目的 探讨从眼镜蛇毒分离纯化出的神经生长因子(nerve grow th facto r, N GF) 对成年猫坐骨神经 损伤后的影响。方法 制成成年猫坐骨神经损伤模型, 损伤局部注射蛇毒N GF 2 Lgö(kg·d) , 分别治疗10 d 和30 d, 并与对照组(损伤坐骨神经, 不给药物) 比较。结果 术后10 d, 对照组术侧远端神经纤维数量比治疗组明显减少 (P < 0. 01) , 治疗组术侧足底刺激出现早, 肢体活动恢复快。术后30 d, 治疗组术侧远端神经纤维大量再生, 再生神 经纤维数量已明显超过对照组和术后10 d 组水平(P < 0. 01) , 但结构紊乱, 轴突和郎氏结消失。术侧肢体在连续注 射N GF 16 d 左右出现足底刺激反应消失, 肢体瘫痪等改变。结论 眼镜蛇毒N GF 在神经损伤早期应用能减轻神 经纤维发生的溃变, 促进受损神经的再生与功能恢复; 而损伤局部长时间注射蛇毒N GF 则会导致神经纤维增生过 度, 丧失传导功能。

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目的:探讨从眼镜蛇毒分离纯化出的神经生长因子(nerve growth factor ,NGF) 对成年猫坐 骨经损伤后的影响。方法: 本实验制成成年猫坐骨神经损伤模型, 损伤局部注射蛇毒NGF(2μg/ kg/ d) ,分别治疗10d 和30d ,并与对照组(损伤坐骨神经,不给药物) 比较。结果:眼镜蛇毒NGF 在 神经损伤早期应用能减轻神经纤维发生的溃变,促进神经纤维再生。结论: 损伤局部长时间注射 NGF 会导致神经纤维增生过度,丧失传导功能。

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目的:控制中华眼镜蛇蛇毒神经生长因子产品质量,研究其理化性质及生物学活性的定性和定量。方法:通过离子交换色谱、凝胶过滤及FPLC色谱分高纯化得到中华眼镜蛇蛇毒神经生长因子,按国家新药审批有关要求对其进行了SDS-PAGE电泳,N端蛋白质序列规定,HPLC色谱分析,UV光谱图谱扫描,并利用PC12细胞培养法和鸡胚背根神经节培养法检测其生物活性。结果:电泳为一条带,亚基分子量为13500,N端蛋白质序列测定后确证为神经生长因子(NGF),HPLC为单峰,相对百分含量为95%以上,279.6nm处呈现出蛋白质样特征吸收峰。生物活性测定为,PC12细胞培养法灵敏度可达1ng/ml,鸡胚背根神经节培养法需30ng/ml的浓度梯度才能在神经节上有所反应。结论:此实验样品为具有较高生物活性的高纯度NGF多肽。

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The masticatory apparatus for two endemic species of golden monkey in China, Rhinopithecus bieti and Rhinopithecus roxellana, were compared with those of macaques, Macaca and leaf monkeys, Presbytis. Multivariate analyses demonstrated that the two golden monkey species are distinct. Interspecies allometric analyses revealed that golden monkeys differ in their masticatory apparatus from both macaques and leaf monkeys. The prominent symphysial fusion, corpus, and sagittal condylar dimension of R. roxellana may produce efficient biting force on the incisal and posterior canine teeth, with the heavy reaction force barn on the temporomandibular joint. However, the well-developed bizygamatic width and mandibular height in R. bieti suggest that posterior canine function is similarly prominent in R. roxellana, while incisal function is not. (C) 1995 Wiley-Liss, Inc.