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Ketaki Karnik Jean K. Reichle Anthony J. Fischetti Justin M. Goggin 《Veterinary radiology & ultrasound》2009,50(1):65-68
The computed tomographic (CT) findings of fungal rhinitis/sinusitis in cats were characterized. The CT images of 10 cats ranging in age from 7 to 13 years were examined. The mean age was 10.8 years and all were neutered males. Nasal aspergillosis was diagnosed in five cats, cryptococcosis in three cats, hyalohyphomycosis in one cat, and trichosporonosis in one cat. Bilateral disease was present in eight cats, seven had abnormal soft tissue attenuation in two-thirds of the nasal cavity, and six had turbinate lysis. Seven cats had also lysis of the hard palate, nasal septum, or frontal bone. One cat had lysis of the cribriform plate. Five of the nine cats whose lymph nodes were imaged had lymph node enlargement. There was contrast medium enhancement in the nasal cavity in all cats, with either a primarily peripheral rim or heterogeneous pattern. There appears to be an overlap of clinical signs, age, and CT features of cats with nasal neoplasia and those with fungal rhinitis/sinusitis. 相似文献
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Judy E. Brown DVM MSc ; Alexa M.E. Bersenas DVM MSc DACVECC ; Karol A. Mathews DVM DVSc DACVECC Carolyn L. Kerr DVM PhD DVSc DACVA 《Journal of Veterinary Emergency and Critical Care》2009,19(5):416-425
Objective – The primary objective of this study was to assess the feasibility of noninvasive mechanical ventilation (NIV) in cats. The secondary objective was to determine whether cardiovascular parameters and anesthetic drug requirements associated with noninvasive ventilation differ from those associated with invasive ventilation. Design – Randomized, cross‐over design. Setting – A research laboratory in a veterinary teaching hospital. Animals – Eight healthy adult cats, 3 intact females and 5 intact males, weighing between 3 and 6 kg, were used. Interventions – Each cat was randomly assigned to NIV via nasal mask, or invasive ventilation using an endotracheal tube. Mechanical ventilation was performed for 6 hours. Anesthesia was provided using continuous infusions of propofol and butorphanol. After a minimum 9‐day washout period, the procedure was repeated using the alternate ventilation interface. Measurements and Main Results – Cardiovascular parameters (heart rate, rectal temperature, direct arterial blood pressure), arterial blood gases, drug requirements, sedation score, and ventilation parameters, were monitored throughout the procedures. These values were evaluated using ANCOVA for repeated measures. All cats were effectively ventilated using NIV. There were no significant differences in cardiovascular parameters, drug requirements, or sedation scores between groups. Although PaCO2 values did not differ, PaO2 values were significantly higher in the invasively ventilated group. Inspiratory tidal volumes were similar between groups, whereas expiratory tidal volumes were significantly lower in the NIV group. Inspiratory pressures were significantly higher in the NIV group. Respiratory frequency was significantly higher in the invasively ventilated group. Conclusions – NIV of cats is possible. However, currently it does not confer any cardiovascular benefit over invasive ventilation and drug requirements are similar. Use of a correctly fitted mask is essential for successful NIV as air leaks account for the observed discrepancy between inspiratory and expiratory volumes. Further investigation into this modality is warranted. 相似文献
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实验研究了陶瓷磨削时脆性破坏和塑性变形两种材料去除机理所产生的声发射信号特征,找出了它们之间的区别,为陶瓷等硬脆材料磨削时实现实时监测其加工、改变磨削工艺参数,使其尽可能地进行半延迟性磨削提出了可靠的依据。 相似文献
306.
分泌IgA和IgG的浆细胞是黏膜免疫系统中两种重要的效应细胞。本研究旨在探究分泌IgA和IgG的浆细胞在家兔鼻腔中的分布特征。以20只健康成年家兔为研究对象,根据硬腭褶皱和牙齿特征,依次将家兔鼻腔分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ 5段,运用组织学、免疫组织化学、图像分析及统计学方法,对分泌IgA和IgG的浆细胞在家兔鼻腔中的分布特征进行了详细的研究。免疫组化结果显示:分泌IgA和IgG的浆细胞在家兔鼻腔每段都有分布,主要弥散分布于鼻黏膜固有层中;其形态呈圆形或卵圆形,核一般位于细胞一侧,胞质丰富呈阳性反应。统计结果显示:分泌IgA和IgG的浆细胞在鼻腔不同段的分布密度由高到低依次是:鼻腔第Ⅳ段、第Ⅴ段、第Ⅲ段、第Ⅱ段、第Ⅰ段。其中分泌IgA的浆细胞在鼻腔Ⅲ、Ⅳ、Ⅴ段的分布密度显著高于鼻腔Ⅰ、Ⅱ段(P<0.05),在上颌鼻甲、鼻中隔和筛鼻甲的分布密度显著高于上鼻甲(P<0.05);与分泌IgA的浆细胞相比,分泌IgG的浆细胞除鼻腔第Ⅳ段的分布密度显著高于鼻腔Ⅲ、Ⅴ段(P<0.05)外,其分布变化趋势基本与分泌IgA的浆细胞类似。结果证明,分泌IgA和IgG的浆细胞弥散分布于家兔每段鼻腔的鼻黏膜固有层中,有利于SIgA和IgG分子在整个鼻黏膜形成完整的保护屏障;分泌IgA和IgG的浆细胞主要分布在家兔鼻腔Ⅲ、Ⅳ、Ⅴ段及上颌鼻甲、筛鼻甲和鼻中隔,提示这些区域是家兔鼻腔免疫的重要效应部位。本研究为家兔呼吸系统疾病的预防及进一步探讨家兔鼻腔免疫应答的机制提供重要的理论依据。 相似文献