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51.
CANINE BRAIN ANATOMY ON MAGNETIC RESONANCE IMAGES 总被引:1,自引:1,他引:0
Susan L. Kraft DVM Patrick R. Gavin DVM PHD Lyle R. Wendling MD Venkat K. Reddy BVSC PHD 《Veterinary radiology & ultrasound》1989,30(4):147-158
Magnetic resonance (MR) images of the canine brain were acquired during investigation of dogs with neurologic disease. A paramagnetic contrast medium was used for enhancement. MR provided images with excellent contrast between grey and white matter, as well as brain tissue and cerebrospinal fluid. Good resolution and anatomic detail of the canine brain were obtained. A series of images was compiled and labelled as a reference for MR anatomy of the canine brain. 相似文献
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目的观察粒细胞集落刺激因子(G-CSF)对脑挫伤大鼠血清及脑组织中一氧化氮(NO)、丙二醛(MDA)和超氧化物歧化酶(SOD)含量的影响,探讨G-CSF在治疗脑挫伤中的作用.方法将大鼠随机分为治疗组、对照组和正常组,采用自由落体法致SD大鼠脑挫伤动物模型,正常组不致伤.治疗组脑挫伤2h后开始应用G-CSF(浓度为2mg/L)一次性皮下注射50μg/kg治疗.对照组和正常组皮下注射等量生理盐水.给药结束后24h检测治疗组、对照组及正常组大鼠血清及脑组织中NO、MDA和SOD的含量.结果脑挫伤后,对照组大鼠血清及脑组织中NO和MDA含量明显高于正常组,SOD的活性明显低于正常组.治疗组大鼠血清及脑组织中NO和MDA含量明显低于对照组,SOD的活性明显高于对照组.结论G-CSF能有效地提高脑挫伤大鼠血清及脑组织中SOD的活性,降低NO和MDA含量,保护脑组织,改善脑水肿,从而起到了一定的治疗作用. 相似文献
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杨秀清 《山东农业大学学报(自然科学版)》2012,43(2):283-286
随着社会、经济的发展,人才对于企业的发展起着越来越重要的作用,对我国的民营企业的生存与发展更起着决定性的作用。然而民营企业的人才流失现象相当严重,给民营企业带来了不可估量的损失。如何降低人才流失率,留住优秀的人才已成为我国民营企业亟需解决的棘手问题。本文从员工需求角度探讨了我国民营企业人才流失的原因并提出留住人才的相应对策,分析了人才流失的严重后果以及结合相关实例的分析,以期为民营企业和相关研究人员提供参考和借鉴。 相似文献
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Iacovetta C Rudloff E Kirby R 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2012,41(1):32-44
Emerging evidence suggests that aquaporin (AQP) 4 water channels play an important role in water homeostasis in the brain. These water channels are most abundant in the cell membrane of astrocytes, but are also present within ependymal cell membranes and in osmosensory areas of the hypothalamus. Water transport through AQP4 depends on concentration gradients across the membrane, but the rate of transport is determined by the capacity of astrocytes to up- and down-regulate AQP4 numbers, their location within the membrane, and the overall permeability of the channel. Other functions of brain AQP4 involve potassium uptake and release by astrocytes, migration of glial cells, glial scarring, and astrocyte-to-astrocyte cell communication. AQP water channels are involved in formation and control of edema in the brain and in multiple disease processes in the brain, such as seizures and tumors. There is abundant scientific literature on AQP4 describing its structure, function, location, and role in water homeostasis and edema in the brain. Investigation of AQP expression in the canine and feline brain should be pursued so that clinically relevant comparisons between findings in mice, rats, and people and animal patients can be made. 相似文献
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Steinberg TA Boettcher IC Matiasek K Hirschvogel K Hartmann K Kunz A Kuntz A Fischer A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2008,37(2):207-216
BACKGROUND: Inflammation of the central nervous system (CNS) is a frequent condition in cats but etiology often remains unsolved. Routine cerebrospinal fluid (CSF) analysis can be extended through the calculation of the albumin quotient (Q(alb)), a marker of the integrity of the blood-brain barrier (BBB), and IgG index, an estimate of intrathecal IgG synthesis. OBJECTIVES: The purpose of this study was to validate nephelometric methods for CSF protein analysis, and to use the Q(alb) and IgG index to discriminate blood- and brain-derived immunoglobulin fractions in cats with feline infectious peritonitis (FIP). METHODS: Cats presented to our clinic between 2001 and 2005 were included in the study based on clinical and laboratory data and histopathologic findings at necropsy. Cats were grouped as having nonneurologic disease (controls; n=37), brain tumors (n=8), FIP involving the CNS (n=12), and extraneural FIP (n=12). CSF-total protein (TP) was measured and albumin and IgG concentrations were measured in paired CSF/serum samples; Q(alb) and IgG index were calculated. Intraassay and interassay precision of the nephelometric assays were determined using pooled samples. RESULTS: Coefficients of variation for the nephelometric assays ranged from 2.7% to 7.2%. In control cats, CSF-TP concentration ranged from 0.06 to 0.36 g/L, Q(alb) ranged from 0.6 to 5.7 x 10(-3), and IgG index ranged from 0.3 to 0.6. Q(alb) and IgG index were significantly higher in cats with brain tumors and cats with CNS-FIP compared with other groups. Compared with control cats, pleocytosis was evident in 8 of 12 (67%) cats and CSF-TP was increased in 3 of 12 (25%) cats with CNS-FIP. CONCLUSION: Nephelometry is a reliable method for measurement of CSF protein, albumin, and IgG in cats. The Q(alb) and IgG index did not identify a CSF protein pattern specific for BBB dysfunction or intrathecal IgG synthesis in cats with CNS-FIP. 相似文献