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61.
The cerebellar Purkinje cells in the hemizygote of the macular mutant mouse contain numerous abnormal mitochondria which show a marked decrease in cytochrome c oxidase activity. Using histochemical methods we studied the activity of other mitochondrial enzymes, such as NADH diaphorase and succinic dehydrogenase, in the cerebellar cortex of this mutant mouse. Such activities were markedly increased in the Purkinje cells, especially in the soma and stem dendrite, from 10 days after birth in the hemizygote as compared with findings in normal littermates. These results were considered to be due to an increased number of abnormal mitochondria.Supported by the Research Grants nos. 2A-5-03 and 3B-1-04 for Nervous and Mental Disorders from the Ministry of Health and Welfare, and by Grant no. 04670492 of the Ministry of Education of Japanese Government  相似文献   
62.
小鼠实验性糖尿病对胰腺腺泡细胞形态学的影响   总被引:1,自引:0,他引:1  
为了探讨实验性糖尿病对胰腺腺泡细胞的影响,我们用四氧嘧啶对小鼠建造糖尿病模型。8wk后,取小鼠胰尾组织作光镜和电镜观察。结果:实验性糖尿病小鼠胰腺内部分腺泡细胞萎缩、细胞排列松散,并有大量慢性炎症细胞浸润。电镜下可见粗面内质网扩张,线粒体嵴紊乱、空泡变性,胞浆内出现髓样小体,酶原颗粒减少。表明实验性糖尿病对小鼠胰腺腺泡细胞的结构有一定的损害作用,进而使胰腺外分泌部的分泌功能受到影响。  相似文献   
63.
鸡矢藤[Paederia Scandens]提取物0.32mg 加入营养槽内,对小白鼠各期离体子宫的收缩张力、收缩强度、收缩频率以及子宫活动力均有增强作用。与给药前比较,诱导期组分别增加85%、47%、21%和72%;动情期组分别增加70%、77%、41%和41%;非动情组分别增加47%、76%、62%和66%,而且三组间作用无显著性差异。本品还能增强 PGE_2对小白鼠离体子宫的收缩张力、收缩强度、收缩频率以及子宫活动力。与 PGE_2的作用比较,分别增加34%、39%、9%和45%,但收缩频率增加无统计学意义(P>0.05)。上述结果表明,鸡矢藤提取物对小鼠子宫有显著性兴奋作用,而且还能增强PGE_2对小鼠子宫兴奋作用,其机制尚待进一步研究。  相似文献   
64.
Two strains of T. rubrum and one strain of T. mentagrophytes were inoculated into human skin grafted onto BALB/c nude mice by the needle puncture method. Infection was established in 1 of the 10 animals inoculated with fluffy colony type T. rubrum, 2 of the 10 animals inoculated with powdery colony type T. rubrum, and 7 of the 10 animals inoculated with granular colony type T. mentagrophytes, suggesting that the skin grafts are infectible by anthropophilic and zoophilic strains of dermatophytes. T. rubrum infection continued for a maximum of 9 weeks and T. mentagrophytes infection for more than 11 weeks. In the animals inoculated with T. mentagrophytes, fungal elements were localized in the stratum corneum of the human skin grafts. In the acute stage, microabscesses consisting of neutrophils were observed under the stratum corneum in contact with fungal elements; in the chronic stage, epidermal thickening and infiltration, mainly consisting of histiocytes and a smaller number of lymphocytes, was noted in the upper and middle dermis. Ultrastructural findings from the parasites were similar to those of dermatophytosis in man. This experimental system should be useful as a model of chronic dermatophyte infection in the human skin.  相似文献   
65.
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man.  相似文献   
66.
BACKGROUND: Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) are thought to contribute to the airway inflammation and airway hyper-responsiveness (AHR) of allergic asthma. Some differences from allergic asthma have been noted, including airway neutrophilia, and the involvement of ICAM-1 in toluene diisocyanate (TDI) asthma is currently unclear. OBJECTIVE: We utilized mice lacking ICAM-1 expression (ICAM-1(-/-)) to investigate the role of ICAM-1 in airway inflammation and AHR in TDI-induced asthma. METHODS: Male C57BL/6J mice (ICAM-1(+/+)) and ICAM-1(-/-) mice were intranasally sensitized to TDI solution or solvent alone. Airway inflammation, AHR and cytokine secretion were assessed 24 h after challenge by TDI or solvent. The production of antigen-specific IgG and IgE by TDI sensitized and non-sensitized mice was determined. RESULTS: TDI challenge to ICAM-1(+/+) mice induced an increase in airway inflammatory cell numbers, AHR and cytokine secretion of TNF-alpha, macrophage inflammatory protein-2 (MIP-2), IL-4, IL-5 and IFN-gamma into the bronchoalveolar lavage fluid. All these pathophysiological changes were reduced in ICAM-1(-/-) mice. Serum levels of TDI-specific IgG and IgE of ICAM-1(-/-) and ICAM-1(+/+) mice were comparable. CONCLUSION: These results suggest that ICAM-1 plays an essential role in airway inflammation and AHR in TDI-induced asthma.  相似文献   
67.
125I粒子组织间种植对人胃癌裸鼠移植瘤的杀伤作用   总被引:8,自引:3,他引:5  
目的 观察不同剂量^125I粒子对人胃癌裸鼠移植瘤的杀伤作用及组织损伤。方法 建立人胃癌BGC-823细胞裸鼠皮下移植瘤模型,随机分为对照组和实验组,将不同剂量(100、120、140Gy)地^125I粒子植于实验组。30、60d:比较移植瘤抑瘤率,病理组织学、局部皮肤反应、裸鼠体重及白细胞计数。结果30d,100、120、140Gy组抑瘤率分别为51.93%、79.18%、90.22%,病理组织学反应程度多为RCRG2(45.83%),各实验组组间除120Gy与140Gy(P〉O.05)组外,及分别与对照组比较,差异有统计学意义(P〈0.05);局部皮肤反应各实验组与对照组比较,差异有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05)。60d,各组抑瘤率分别为97.97%、100%、96.69%,病理组织学反应程度以RCRG1居多(62.5%),与对照组比较,差异均有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05);局部皮肤反应随剂量增高而加重,各实验组组间及其分别与对照组比较,差异有统计学意义(P〈0.05)。结论 不同剂量的^125I粒子在不同时间对人胃癌裸鼠皮下移植瘤有显著杀伤作用,但120Gy和140Gy组随剂量累积,损伤明显增加。提示100Gy可能是治疗人胃癌裸鼠皮下移植瘤的有效剂量。  相似文献   
68.
69.
Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods.  相似文献   
70.
四氧嘧啶型糖尿病小鼠颌下腺组织学和组织化学的研究   总被引:2,自引:0,他引:2  
本文用四氧嘧啶建造糖尿病小鼠实验模型。建模8wk后,取小鼠颌下腺进行组织学和酶组织化学观察。结果表明:实验性糖尿病小鼠颌下腺的腺泡出现部分萎缩,核固缩的现象,此外,SDH活性下降,LDH活性呈增强趋势。GCT细胞形态结构无明显变化,但SDH、GPDH及ATPase活性降低。提示:实验性糖尿病对小鼠颌下腺的结构和功能有一定的损害作用。  相似文献   
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