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81.
奶山羊颈迷走神经传出神经元胞体的定位和形态学特征 总被引:1,自引:0,他引:1
将HRP注入颈迷走神经干后,在迷走神经背核的全长出现标记细胞,但该核的尾部以特征性的巨、大或中型梭形标记细胞为主而区别于核的前和中部。在孤束内侧核有散在的类似于背核的标记细胞。在疑核可见大、中、小三型标记细胞,但在疑核嘴侧部的腹侧群即面后核无标记物。在疑后核、上颈髓中间带区有类似于胸髓交感节前神经元的中型标记细胞和分布特征。在脊上核的背侧群和上颈髓的腹角背内侧核和副神经脊髓核有一些大多极标记细胞。 相似文献
82.
83.
BENJAMIN SPALL ANNIE V. CHEN RUSSELL L. TUCKER KEVIN K. LAHMERS DANIEL J. RIGHTER JONATHAN HAYLES 《Veterinary radiology & ultrasound》2011,52(5):534-537
A 10‐year‐old Akita mix became acutely paraplegic. Upon magnetic resonance imaging, multiple, slightly T2‐hyperintense, T1‐isointense extradural masses, relative to spinal cord were found in the vertebral canal. The retroperitoneal masses had mixed T2‐signal intensity. The contrast enhancement pattern for the spinal masses was both homogenous and heterogenous. The diagnosis was metastatic pheochromocytoma. Signal intensity of the tumors in this dog was similar to reports of pheochromocytoma in human beings. 相似文献
84.
Judith A. Hudson DVM PhD Susan T. Finn-Bodner DVM MS Joan R. Coates DVM Donald C. Sorjonen DVM MS Stephen T. Simpson DVM MS James C. Wright DVM PhD Jan E. Steiss DVM PhD Nancy R. Cox DVM PhD Dana M. Vaughn DVM PhD Starr C. Miller BS Scott A. Brown DVM PhD Phillip D. Garrett DVM MS 《Veterinary radiology & ultrasound》1995,36(6):542-547
Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06. 相似文献
85.
陈敏 《金陵科技学院学报》2005,21(1):47-50
介绍不确定度的基本概念和数学模型,并对材料力学性能测试中常见的钢筋抗拉强度检测中的不确定度进行了简要的分析和评定。 相似文献
86.
对山羊胚胎脊髓胶状质发育的形态学变化了系统研究,结果表明:(1)山羊脊髓胶状质在胚胎第17周以后逐渐较多的神经元胞体和较大的淡染的神经元细胞核,提示胚胎第17周龄是山羊脊髓胶状质神经元发育的关键时期;(2)山羊脊髓胶状质内神经纤维在胚胎第11周时就已出现,而在髓神经纤维的髓鞘则在胚胎第15周时形成,以后逐渐发育成熟;(3)山羊脊髓胶状质的胶质细胞发育较早,在胚胎第6周末胶状质的胶质细胞发育较早,在胚胎第6周末胶状质原基刚形成时,胶质细胞核已经开始分化,到胚胎第18-19周时,胶质细胞又出现一个增殖高峰。 相似文献
87.
徐近孝 《新疆农业大学学报》1988,(2)
发动机汽缸和曲轴修理中,往往影响发动机压缩比的变化。由于燃烧室结构形状复杂,给计算压缩比变化带来不便。本文通过分析,提出了计算压缩比变化的简便方法。 相似文献
88.
B Funkquist 《Acta veterinaria Scandinavica》1975,16(2):269-287
Metrizamide is a new water-soluble contrast medium possessing unique properties, one of which is that even in an isotonic solution it has a radiographic density sufficient for a diagnostic myelogram. Whereas in the past myelography with water-soluble preparations invariably entailed lumbar injections, which are technically difficult in dogs, the fact that isotonic metrizamide causes so little tissue irritation has made it possible to inject the contrast solution into the cisterna magna. The author has compared metrizamide myelograms obtained with both cisternal and lumbar injections. Myelography with a cisternal injection is preferable for demonstrating cervical cord compressions and also in cases in which it is desirable to obtain myelographic information on both the cervical and the thoraco-lumbar areas. If, on the other hand, it is necessary to determine exactly the extent of a thoraco-lumbar compression before decompressive laminectomy, the contrast should be injected in the lumbar region in such an amount and at a pressure high enough to ensure that the contrast is forced past the site of the compression. The safety of metrizamide will probably enable a better prognosis following surgery than was previously possible. 相似文献
89.
J Nielsen 《Acta veterinaria Scandinavica》1986,27(3):343-350
Mononuclear cells isolated from thymus, spleen and cord blood of pig fetuses ranging in age from 48 to 112 days were examined for the presence of sheep red blood cell rosette-forming cells (SRBC-RFC). After an initial increase from 77 % (mean) at 48 days of gestation to 88 % at 60 days, the proportion of SRBC-RFC in thymus remained constant throughout the gestational period. In spleen and cord blood, the proportion of SRBC-RFC increased with age, from occasional rosette-forming cells at 48 days of gestation to 21 % and 30 %, respectively, at 112 days. The demonstrated development of SRBC-RFC in the thymus, spleen and cord blood is considered to reflect the ontogeny of T cells in these fetal pig tissues. 相似文献
90.
猪的荐骨棘突很不发达,两侧的腰荐尾部背侧区的肌肉有如下特点:臀中肌、腰后多裂肌和荐尾背内侧肌的后端肌腹都与对侧同肌紧密为邻;腰多裂肌的后部肌腹发达,命名为腰后多裂肌;荐尾副背外侧肌是猪特有的肌肉,在解剖文献中没有任何记载,故而命此名称,呈窄长条状小肌,位于荐尾背外侧肌的外侧. 相似文献