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1.
目的探讨用4.7特斯拉试验用磁共振成像系统能否在豚鼠中检测内淋巴积水.方法20只白色或者杂色豚鼠用于该研究.5只正常豚鼠作为对照组,15只豚鼠用于制作内淋巴积水模型.9只内淋巴囊破坏组中的5只和6只内淋巴囊完整组(与乙状窦游离)动物采用gadolinium(Gd)-DTPA-BMA增强MRI检测内淋巴积水.结果由于Gd-DTPA-BMA主要进入鼓阶和前庭阶,耳蜗的三个阶可在所有动物中由MRI清晰显示.在内淋巴囊完整组,内淋巴囊手术后6天MRI即可检测到内淋巴积水,并且由组织学证实.在内淋巴囊破坏组中的1只动物,因内耳屏障的严重破坏而使Gd-DTPA-BMA快速漏入中阶,MRI可检测到该变化,其听力损失为60dB.结论用Gd-DTPA-BMA增强的高分辨MRI可检测出内淋巴积水,有可能对积水程度进行定量测试.在Gd-DTPA-BMA的帮助下,内耳屏障损伤或可能的膜破裂可以被检出.  相似文献   

2.
人们对内淋巴积水的认识一般源于梅尼埃病,迄今为止,梅尼埃病的病因不甚明了。由于临床上无法行活体内耳病理检查,而现有检查手段特异性均不高,故对于内淋巴积  相似文献   

3.
目的探讨模拟失重和噪声复合因素对豚鼠内耳淋巴液容积的影响。方法健康豚鼠24只随机分为单纯失重组12只、单纯噪声组6只、失重+噪声组6只,分别测试实验前、实验5天及实验结束后3天听性脑干诱发电位(ABR)阈值及内耳MRI扫描,并用自制专用软件对内耳淋巴液容积进行计算。结果单纯噪声组实验前后内耳容积无差异(P>0.05);单纯失重组实验5天与实验前、实验结束后3天与实验5天相比有显著性差异(P<0.01),实验结束后3天与实验前相比无明显差异(P>0.05);失重+稳态噪声组实验5天及实验结束后3天豚鼠内耳容积较实验前明显增大(P<0.01),实验5天与实验结束后3天豚鼠内耳容积无显著差异(P>0.05)。结论失重环境可使豚鼠内耳淋巴液容积变大,但是短期单纯失重环境豚鼠内耳淋巴液容积变化可恢复,失重加噪声复合因素会加重内耳淋巴液容积变化,且实验后3天后内耳淋巴液容积无恢复。  相似文献   

4.
内耳结构相当复杂、深在,当其出现病变时只依靠临床体征及临床表现去判断,缺少客观的评判指标,尤其对膜迷路积水的情况.随着磁共振成像技术和内耳钆造影技术的发展,内耳的精细结构已经可以显像.本文就磁共振内耳成像及钆造影技术的原理及在内耳相关疾病的应用做一综述.  相似文献   

5.
目的通过无创性经咽鼓管中耳腔导入造影剂钆行内耳3D-FLAIR MRI扫描的方法,对梅尼埃病患者组受试者进行研究,得到该年龄组耳蜗及前庭内耳内淋巴间隙的比值,并与20~55岁组正常值进行比较。方法在鼻内窥镜引导下,将稀释的钆喷酸葡胺注射液通过咽鼓管注入患耳中耳腔,给药1 d后行3D-FLAIR MRI扫描,得到内耳内淋巴间隙的显影,并对内耳内淋巴间隙、总淋巴间隙进行测量和计算,得到内耳内淋巴间隙与总淋巴间隙的比值,并与正常受试者组数据进行比较。结果在患者3D-FLAIR MRI扫描图像中可见耳蜗及前庭部内耳内淋巴间隙显影。对患者组3D-FLAIR MRI图像进行总淋巴间隙面积和内淋巴间隙面积的测量和计算,内淋巴间隙与总淋巴间隙面积之比为内耳内淋巴间隙的比值(前庭为RV,耳蜗为RC)。前庭内耳内淋巴间隙的比值为0.39±0.07,耳蜗内耳内淋巴间隙的比值为0.16±0.05。与20~55岁正常受试者组比较,两组RV差异有统计学意义(t=-6.07,P0.05);两组的RC无统计学差异(t=0.783,P0.05)。依据刘芳等提出的内耳内淋巴积水的诊断标准(RV39%,RC27%),梅尼埃病患者组前庭内淋巴间隙积水阳性率为42.9%,耳蜗内淋巴积水阳性率为9.52%。处于梅尼埃病发作期的两位患者RV值测量均为阳性。结论梅尼埃病患者组与正常受试者组相较,两组RV值有显著差异,患者组RV值明显大于正常受试者组;两组RC值无明显差异。前庭内淋巴积水诊断阳性率为42.9%,2例发作期患者均存在前庭内淋巴积水阳性;耳蜗内淋巴积水诊断阳性率为9.52%。  相似文献   

6.
目的为探讨鼓室注射钆喷酸葡胺(Gd-DTPA)内耳增强显影的造影剂药物代谢动力学,设计体外试验探索造影剂浓度与核磁信号增强强度之间的相关性。方法配制不同浓度Gd-DTPA溶液,行3D-T1 FSE序列扫描后使用核磁工作站读取图像信号强度(SI),并将其与造影剂浓度行相关性及回归分析。结果 Gd-DT-PA在较低浓度范围内(≤1 mmol/L),SI与造影剂浓度呈良好的线性关系,并得到回归方程:Y=23 388X+8 120.1(决定系数r2=0.96,Y为SI;X为Gd-DTPA浓度,单位mmol/L)。结论应用此体外试验所得的回归方程,将鼓室注射造影剂后内耳扫描获得的增强信号强度转化为造影剂浓度,即可用来研究造影剂内耳药物代谢动力学规律。  相似文献   

7.
随着内耳钆造影磁共振成像技术的出现,为多种内耳疾病的诊断提供了新方法,也为梅尼埃病的诊断提供新契机,甚至有望成为其诊断的金标准。论文围绕国内外鼓室钆造影技术的发展现状,归纳了钆造影的磁共振成像技术特点、给药方式、评估方法及与传统检查方式进行了对比,总结了内耳钆造影磁共振成像技术在梅尼埃病诊疗中的研究现状。  相似文献   

8.
目的借助磁共振成像系统,观察新给药方式耳后给药,药物在内耳的吸收过程,探讨耳后给药治疗内耳疾病的可行性。方法 12只白色红目豚鼠随机分为2组,一组耳后注射造影剂,一组静脉注射造影剂。7.0T小动物专用磁共振成像系统,在给药前、给药后0.5h、1h、2h、3h、4h、6h、8h、12h、24h、48h,分别进行磁共振T1加权像成像。测量右侧耳蜗底转鼓阶的信号强度,描绘信号-时间曲线,计算曲线下面积,对比耳后组与静脉组之间的差异。结果耳后组与静脉组信号-时间曲线下面积分别为68.14×105及36.17×105,耳后组面积更大,差异有统计学意义(P<0.05)。结论耳后给药治疗内耳疾病是可行的,局部疗效好,全身并发症少,便于在临床推广应用。  相似文献   

9.
目的 通过MRI观察豚鼠鼓膜穿刺听泡内注射钆喷酸葡胺后内耳增强显影的特征,观察不同时间点造影剂在内耳的分布,找出内耳增强显影的最佳时间,同时了解钆喷酸葡胺在内耳的药代动力学特点,探讨在现有实验条件下内、外淋巴区分显影的可行性.方法 65只豚鼠随机数字表法分为13组,每组5只.豚鼠鼓膜穿刺听泡内注射生理盐水稀释8倍的钆喷酸葡胺,分别在注射前、注射后0.5、1、2、4、6、8、10、12、24、48、72及96 h行内耳MRI扫描(3D-T1 FSE序列).使用e-Film软件对内耳各部位MRI图像灰度值进行提取,应用体外试验获得的灰度值-造影剂浓度关系将灰度值转化成浓度.分别测量注射前、注射后1 d及7 d豚鼠左耳(生理盐水)和右耳(稀释造影剂)的听性脑干反应(ABR)阈值并进行对比.结果 注射后6 h为造影剂扩散至全内耳并达到较好显影条件的时间点,也即造影剂在内耳各部分达到较高浓度的时间,此时造影剂在前庭、底转鼓阶、底转前庭阶、第二转、第三转、顶转的浓度分别为589.29、552.54、570.17、255.08、107.09、139.18 μmol/L;造影剂选择性进入外淋巴,未见内淋巴增强显影.造影剂注射后1 d及7 d豚鼠左、右耳ABR阈值相比,差异无统计学意义(P值均>0.05).结论 豚鼠听泡内注射钆喷酸葡胺后6 h为MRI内耳增强显影的最佳观察时间.造影剂可选择性显影外淋巴,对豚鼠ABR阈值无明显影响.通过MRI可以间接研究钆喷酸葡胺在内耳的代谢特点.  相似文献   

10.
目的针对拟诊为梅尼埃病的患者,以MRI检测内淋巴积水为方法,探讨在梅尼埃病诊断中以此方法确诊为内淋巴积水的可行性,并评估临床诊断价值,分析影响判定结果的相关因素。方法选择2013.6月-2014.11月间住院病人梅尼埃病43例做为研究对象,经鼓室注射钆喷酸葡胺造影剂24小时后进行内耳MRI检查,MRI扫描序列为T1加权三维自旋回波序列(3D-FSE-T1WI),所得图像以前庭和耳蜗底转各自内淋巴面积占内外淋巴面积之和的比率大于1/3为阳性,应用三分法进行定性判定,进行计数并统计。结果在43例梅尼埃病中,35例(81.40%)在前庭发现内淋巴积水,4例(9.30%)未发现积水,另外4例(9.30%)不能确定;在耳蜗,36例(83.72%)发现内淋巴积水,3例(6.98%)未发现积水,另外4例(9.30%)不能确定。结论鼓室内注射顺磁性造影剂后内耳MRI检查可发现内淋巴积水,是临床确定内淋巴积水有效和可行的方法。其主要影响因素包括造影剂进入内耳受阻扩散不良、鼓室给药技术、MRI检测技术及主观判定因素。  相似文献   

11.
Objective Adipose-derived stem cells(ADSCs) are suggested to possess a highly plastic ability to differentiate into several specific cell types in addition to adipocyte lineages, including germ layer tissue-specific cell lineages such as chondrocyte, myocyte, neuronal, and osteoblast lineages. The aim of this study is to establish an in vitro culture technique for ADSCs in an adult guinea pig model that facilitate their differentiation into hair cell-like cells. Materials and Methods Cells from inguinal fat pads in adult guinea pigs were cultured with β-mercaptoethanol, RA, Forskorin, Heregulin, bFGF, BDNF and EGF. Cellular differentiation was examined using immunocytochemistry techniques. Results The ADSCs demonstrated hair cell immunophenotypes with expression of epitopes of the hair cell marker protein myosin Ⅶa. Conclusion ADSCs from adult guinea pig adipose tissue can differentiate into hair cell-like cells when cultured in vitro. ADSCs may serve as seed cells for tissue engineering.  相似文献   

12.
Sensitivity to changes in the interaural correlation of 50-ms bursts of narrowband or broadband noise was measured in single neurons in the inferior colliculus of urethane-anaesthetized guinea pigs. Rate vs. interaural correlation functions (rICFs) were measured using two methods. These methods compensated in different ways for the inherent variance in interaural correlation between tokens with the same expected correlation. The shape of all rICFs could be best described by power functions allowing them to be summarized by two parameters. Most rICFs were best fit by a power below 2, indicating that they were only slightly nonlinear. However, there were a few fitted functions that had a power of 3–6, indicating marked curvature. Modeling results indicate that the nonlinearity of the majority of rICFs was explicable in terms of the monaural transduction stages; however, some of the rICFs with power greater than 2 require either multiple inputs to the coincidence detector or additional nonlinearities to be included in the model. Discrimination thresholds were estimated at reference correlations of −1, 0, and +1 using receiver operating characteristic (ROC) analysis of the spike-count distribution at each correlation. Thresholds spanned the full possible range, from a minimum of 0.1 to the maximum possible of 2. Thresholds were generally highest with a reference correlation of −1, intermediate with a reference of 0, and lowest with a reference correlation of +1. Thresholds were lowest for the most steeply sloped rICFs, but thresholds were not strongly correlated to the spike rate variance. The lowest thresholds occurred using narrowband noise that was compensated for internal delays, but they were still about three times larger than human psychophysical thresholds measured using similar stimuli. The data suggest that, unlike pure tone interaural time difference, discrimination of a population measure is required to account for behavioral interaural correlation discrimination performance.  相似文献   

13.
Effects of exposure to noise on ion movement in guinea pig cochlea   总被引:1,自引:0,他引:1  
Healthy guinea pigs were exposed to broad band noise at levels between 95 and 115 dBA for 7 days. A significant decrease of the sound-induced cochlear responses, together with a substantial increase of the endocochlear potential, was observed in guinea pigs exposed to noise at 105 or 115 dBA. Microsamples of the endolymph obtained from these guinea pigs showed a significant increase of K+ and Cl- concentrations and a decrease of Na+ concentration, when compared with those from control animals. The K+, Na+ and Cl- concentrations in the perilymph were not markedly affected by noise exposure. When the perilymphatic space was perfused with artificial perilymph containing 43K, 22Na or 36 Cl, the uptake of radiotracers into the endolymph showed a single exponential function of the perfusion time. When compared with rate constants in normal animals, the value of rate constant for K+ was significantly decreased in animals exposed to noise. These results indicate that ionic permeability changes of the endolymph-perilymph barrier are a significant factor in the physiological mechanisms underlying noise-induced hearing loss.  相似文献   

14.
葛根对老年豚鼠听功能的保护作用   总被引:1,自引:1,他引:1  
目的 观察葛根是否对老年豚鼠听功能具有保护作用.方法 选取16只28~30月龄豚鼠,随机分为用药组和对照组,每组8只.用药组豚鼠皮下注射葛根提取液2 g·kg~(-1)·d~(-1),对照组使用等量生理盐水注射,共8周.观察两组豚鼠用药前及用药结束后ABR反应阈的变化;应用基底膜荧光染色铺片比较两组动物基底膜的变化.结果 注射葛根后用药组ABR反应阈提高4.84±3.28 dB,较对照组(11.12±3.72 dB)明显减少(P<0.05),基底膜荧光染色铺片显示用药组毛细胞缺失数目较对照组减少.结论 葛根对老年豚鼠听功能具有保护作用.  相似文献   

15.
将40只豚鼠随机分为老年耳聋模型组(甲组)和用牛磺酸治疗的老年聋模型组(乙组),各20只,另外20只自然老年顾(年龄为12个月)的豚鼠作为空白对照组(丙组)。老年聋动物模型是用D-半乳糖行眼球后注射制成。结果发现甲组心肌和脑组织中的MDA含量较乙组高,而SOD活力则较乙组低。甲组和丙组脑组织的脂褐质含量均较乙组高。甲组和丙组的组织病理学改变相对于乙组来说是相同的。我们的研究结果表明,牛磺酸在预防D半乳糖所致的豚鼠老年聋中有良好效果  相似文献   

16.
《Acta oto-laryngologica》2012,132(2):302-305
Objectives – To clarify the localization of cyclooxygenase (COX)-1 and -2 in the nasal cavity of guinea pigs and ascertain their physiological roles.Material and Methods – The distribution of the enzymes was investigated using immunohistochemistry.Results – Immunoreactivities for COX-1 and -2 were limited to the nasal glands, and no expression was noted in the surrounding vascular endothelial cells, olfactory glands, respiratory epithelium, olfactory epithelium, submucosal tissue or nerves. To confirm the specificity of the reaction, the kidneys of the same animals were prepared as positive controls. The results demonstrated localization of COX-1 and -2 in uriniferous tubules.Conclusion – Our findings suggest that COX is involved in the secretion of nasal discharge from the nasal glands and that prostaglandins in the nasal discharge are probably secreted directly from the nasal glands.  相似文献   

17.
急性缺氧对豚鼠40Hz听觉相关电位的影响   总被引:3,自引:0,他引:3  
目的:探讨急性缺氧条件下豚鼠40Hz听觉相关电位的改变。方法:利用气管持管辅助呼吸并给予不同浓度低氧气体建立动物模型,观察在不同程度的急性缺氧条件下,豚鼠40Hz听觉相关电位的改变,结果轻度缺氧条件下40Hz听觉相关电位各项参数无明显改变,加重缺氧则其阈值升高,各波平均振幅降低,P1波潜伏期延长,结论:40Hz听觉相关电位在轻度缺氧条件下比较稳定,这可能与40Hz听觉相关电位本身的特性有关,严重缺氧则表现为抑制。  相似文献   

18.
OBJECTIVES/HYPOTHESIS: The effect of topical administration of edaravone to the inner ear was investigated in guinea pigs with streptomycin-induced vestibulotoxicity. METHODS: Vestibulotoxicity was induced in 20 animals by delivery of streptomycin into the inner ear through osmotic pump for 24 hours. Edaravone (n = 8, systemic administration group) or saline (n = 6, control group) was injected intraperitoneally once a day for 7 days or edaravone-soaked Gelfoam was placed on the round window before wound closure (n = 6, topical administration group). RESULTS: Yaw head tilt and spontaneous nystagmus were observed in all animals after the operation. The number of spontaneous nystagmus beats in the topical administration group was statistically less than that in other two groups at 12, 18, and 24 hours after the operation. CONCLUSION: The study results suggest that topical administration of edaravone better suppresses streptomycin-induced vestibulotoxicity than systemic administration.  相似文献   

19.
目的探讨氨基甙类药物对内淋巴积水豚鼠前庭及耳蜗功能的影响。方法8只内淋巴积水模型豚鼠全身应用链霉素,观察给药前后豚鼠行为学、眼震电图(ENG),听性脑干反应(ABR),畸变产物耳声发射(DPOAE)及形态学变化。结果给药后未出现头偏斜、走路不稳等前庭功能紊乱的行为征象,连续给药第10天、停药后第7天摆动幅度90°,停药后第21天,摆动幅度为90°、120°时积水侧眼震反应降低的幅度明显大于对照耳(  相似文献   

20.
后半规管阻塞前后豚鼠前庭及耳蜗功能的动态变化   总被引:5,自引:1,他引:5  
目的 探讨机械性后半规管阻塞前后豚鼠前庭和耳蜗功能的动态变化。方法 采用20只豚鼠建立单侧后半规管阻塞的动物模型,观察手术前后眼震电图,听性脑干反应,耳声发射等变化。结果 术后第1天,第3天豚鼠正弦摆动刺激术侧眼震反应,明显减术,术后第5天起双侧眼震恢复正常。术后早期ABR阈值一度升高,第5天达高峰,ABR阈值平均升高4.5dB。DPOAE反应幅度无明显改变。结论 后半规管阻塞能选择性地消除后半规  相似文献   

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