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101.
肺螨病的病理观察   总被引:2,自引:0,他引:2  
本文报道螨类接种豚鼠气管引起的肺部病变,并对5种常见螨类的致病性进行比较。发现螨类接种后6天豚鼠肺部已形成典型的结节性病灶。结节圆锥形淡黄色,直径1~5mm之间。镜下表现为细支气管炎和细支气管周围炎,肺实质内有明显的异物肉芽肿形成,炎症在螨类接种豚鼠20天时,肺部嗜酸粒细胞浸润不明显,但30或40天时则出现明显的嗜酸细胞浸润,细支气管周围小动脉受到损害,部分小动脉内可见到螨体残骸。5种常见螨炎接种于5组豚鼠可引起大致相同的病变。从而证明豚鼠可作为动物模型以供肺螨病的研究,同时也证明5种常见贮藏螨具有相同的致病性。  相似文献   
102.
Since lung transplant recipients are susceptible to infections and inhaled pollution, many centers warn against pets. However, data supporting this recommendation are lacking. Our program is less restrictive regarding pets. This study, for the first time, investigates the association of pets with physiological and psychological parameters in these patients. A questionnaire concerning pets was sent to 104 lung transplant recipients. Lung function tests, levels of exhaled nitric oxide (FE(NO)), need for antibiotic treatments and hospitalizations, creatinine clearance, body mass index (BMI) and demographic data were assessed. Additionally, the questionnaire of life satisfaction (FLZ), a question on summarized life satisfaction (LS), the life orientation test (LOT), the hospital anxiety depression scale (HADS) and the social support questionnaire (F-SozU) were assessed. Response rate was 86%. Fifty-two percent defined themselves as pet owners, whereas 48% did not. The two groups did not differ in demographic or physiological data. Significant differences in FLZ (79/65, p = 0.04), in LS (4.3/3.9, p = 0.01), LOT (32/29, p = 0.006) and F-SozU (4.5/4.2, p = 0.04) were found in favor of pet owners. In lung transplant recipients keeping pets the frequency of somatic complications is not higher compared to lung transplant recipients without pets. After lung transplantation, pets are associated with a better quality of life.  相似文献   
103.
104.
目的:制备脑干缺血动物模型并观察大鼠脑干缺血后早期组织学病理的超微结构。方法:应用两点电凝基底动脉的方法制作鼠脑干缺血动物模型。结果:病理学观察发现脑干缺血2小时即可出现超早期病理变化,并随时间的延长缺血性损害逐渐加重。结论:两点电凝基底动脉后可以造成稳定的脑干缺血,对急性脑干缺血的病理学研究有一定的价值。  相似文献   
105.
目的以酵母多糖腹腔注射建立老龄大鼠多器官功能不全综合征(MODSE)模型,并进一步与成年多器官功能不全综合征(MODS)模型作比较.方法成年和老龄SD大鼠,腹腔注射不同剂量酵母多糖,以血气、血生化和心、肝、脑、肺、肾等各主要脏器的光镜检查等为指标,观察上述各主要脏器的功能和形态学的变化.结果与成年和老龄正常对照组相比,成年和老龄不同酵母多糖组血气和血生化指标均出现不同程度的改变,肺、心、肝、脑、肾等主要脏器出现明显病理改变.在相同酵母多糖浓度下,老龄组呼吸功能、心脏功能和肾脏功能降低较相应成年组重;在复制模型程度相似的情况下,与成年大鼠相比,老龄大鼠有死亡时间延迟的趋势.结论酵母多糖腹腔注射可复制MODSE模型,以0.5 g/kg腹腔注射最为理想,该模型可用于MODSE机制和实验治疗学的探讨.  相似文献   
106.
目的 观察应用胫骨横向骨搬移法对犬下肢缺血性疾病动物模型的血管再生效果。方法 将 2 0只犬制成下肢缺血性疾病动物模型 ,建模后 1周对犬的后肢施行胫骨横向骨搬移术 ,即在胫骨内侧嵴开一个 5cm× 1cm骨窗 ,以特制的支架每天 1mm速度向外牵拉。分别于不同时期处死动物 ,通过皮温测定 ,光镜下测量血管密度 ,血管造影等方法来观察血管再生情况。结果 在不同时相点观察到伴随着骨的搬移 ,有明显的毛细血管再生现象 (以第 7~ 2 1天为著 )。结论 应用胫骨横向骨搬移法可对犬下肢缺血性疾病动物模型产生明显的血管再生 ,有明显的治疗效果  相似文献   
107.
股骨头骨骺缺血再灌注模型的建立   总被引:9,自引:1,他引:8  
目的:建立缺血再灌注引起幼年兔股骨头骨骺细胞损伤的模型。方法:取12只1kg左右幼年新西兰兔,月龄,性别不限。切开兔髋关节囊,切断圆韧带,显露股骨颈,取皮筋对股骨颈进行加压,皮筋拉力约0.5kg,阻断股骨头骺动静脉血供6h、24h。松开皮筋分别恢复血供6h、24h、168h后取兔股骨头标本。结果:在取标本前进行同位素骨扫描及腹主动脉造影,证实缺血及再灌注有效。常规HE染色及胶原染色病理切片显示:单纯股骨头骨骺缺血6h骨骺骨细胞变性不明显,缺血24h组骨骺骨细胞变性;缺血24h股骨头再灌注168h后骨细胞明显坏死。结论:缺血再灌注可加重幼年兔股骨头骨骺骨细胞损伤。  相似文献   
108.
To study the cause and mechanism of transplantation vasculopathy which characterized by accelerated graft arteriosclerosis ( AGA), we estabfished a mouse aorta graft model. Methods: A segment of thoracic aortas of B10. A (2R) mice were transplanted to C57BL/10 mice abdominal aorta by end to side anastomoses. The different time point collected grafts were analyzed by morphological, histochemical and electro microscopic methods. Results:Rejection was manifested as a concentric progressive destruction of the smooth muscle cells. In contrast, the endothelial inflammation and subsequent ncointimal proliferation characteristic of AGA was localized to the regions of turbulent flow, i.e. the junction of the graft with the recipient aorta. Conclusion: This model separates the processes of rejec-tion and neointimal formation which usually manifested together in the lesion of AGA, elucidate that different mecha-nisms control vascular rejection and neointimal formation in chronic rejection.  相似文献   
109.
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies.  相似文献   
110.
The disaccharide trehalose is a key element involved in anhydrobiosis (the capability of surviving almost complete dehydration) in many organisms. Its presence also confers resistance to desiccation and high osmolarity in bacterial and human cells by protecting proteins and membranes from denaturation. The present study used a novel murine dry eye model induced by controlled low-humidity air velocity to determine whether topically applied trehalose could heal ocular surface epithelial disorders caused by ocular surface desiccation. In addition, the efficacy of 87.6 mM trehalose eyedrops was compared with that of 20% serum, the efficacy of which has been well documented. Mice ocular surface epithelial disorders were induced by exposure of murine eyes to continuous controlled low-humidity air velocity in an intelligently controlled environmental system (ICES) for 21 days, which accelerated the tear evaporation. The mice were then randomized into three groups: the control group received PBS (0.01M) treatment; a second group received 87.6 mM trehalose eyedrops treatment; and the third group received mice serum eyedrops treatment. Each treatment was administered as a 10 μl dose every 6 h for 14 days. The resultant changes in corneal barrier function and histopathologic examination of cornea and conjunctiva were analyzed and the level of apoptosis on the ocular surface was assessed using active caspase-3. After 14 days of treatment, the corneal fluorescein staining area, the ruffling and desquamating cells on the apical corneal epithelium, as well as the apoptotic cells on ocular surface epithelium had significantly reduced in eyes treated with trehalose compared with those treated with serum and PBS. In contrast, after 14 days of treatment, improvements in the thickness of the corneal epithelium, the squamous metaplasia in conjunctival epithelium and the number of goblet cells of the conjunctiva were less marked in eyes treated with trehalose compared with serum. These results demonstrated that trehalose could improve the appearance of ocular surface epithelial disorders due to desiccation through suppression of apoptosis. Trehalose produces some of the same responses as serum upon topical application and can maintain corneal health.  相似文献   
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