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排序方式: 共有838条查询结果,搜索用时 11 毫秒
1.
为了探讨蜂王宝对免疫功能的影响,用蜂王宝对受抑小鼠进行了淋巴细胞增殖,抗体形成细胞等免疫功能试验。在正常淋巴细胞增殖中,蜂王宝组与正常对照组比较差异非常显著(P<0.01),在PHA诱导的小鼠淋巴细胞增殖中,蜂王宝组与正常对照组比较和蜂王宝+强的松龙组与强的松龙组比较差异也非常显著(P<0.01).蜂王宝+强的松龙组与强的松龙组的脾重比较差异有显著性(P<0.05),结果显示,蜂王宝能显著提高受抑小鼠淋巴细胞增殖能力,而对体液免癌无明显作用。 相似文献
2.
幽门螺杆菌尿素酶减毒鼠伤寒杆菌疫苗诱导小鼠粘膜免疫应答的研究 总被引:1,自引:0,他引:1
目的:观察口服减毒鼠伤寒杆菌活菌重组疫苗后小鼠的粘膜免疫应答状况。方法:将已构建成功的表达幽门螺杆菌(H.pylori)尿素酶B亚单位(UreB)的重组减毒鼠伤寒杆菌SL3261/pTC01-UreB口服免疫Balb/c小鼠,12周后检测肠液和血清中的特异性抗体反应。结果:疫苗组小鼠的肠液和血清中可分别检测到针对UreB的特异性抗体IgA和IgG,病理学检查显示疫苗组小鼠较对照组小鼠胃粘膜炎症程度差异无统计学意义。结论:表达H.pyloriUreB的减毒鼠伤寒杆菌SL3261/pTC01-UreB能够诱导小鼠产生抗H.pylori的粘膜免疫,可用作抗H.pylori感染的口服疫苗。 相似文献
3.
Wei GONG Zhuo-Jing LUO Hua HAN Hong-Yan QIN You-Biao CHU Xue-Yu HU Li-Feng LAN Department of Orthopaedics XiJing Hospital the Fourth Military University Xi''''an China 《中国神经科学杂志》2006,(1)
Objective To invest the efficient method which can culture and induce embryonic stem cells to neurocyte in vitro. Methods Isolate the blastula of 3.5 d from BALB/c species mouse. Culture the cells from inner cell mass (inner cell mass, ICM) which were isolated by mechanical method on the mouse embryonic fibroblaste cell (MEF) feeder layer or 0.1% gelatin coated dishes. The stem cells were identified by characterized morphology, alkaline phosphatase stain, differential potency in vivo and immunochemistry stain. The isolated cells were differentiated by serial induction method that mimicking the intrinsic developmental process of the neural system. Results The isolated cells were positive for alkaline phosphatatse and SSEA-1 (stage specific embryonic antigen 1). Moreover they were identified pluripotent by differentiation in vivo. Therefore the isolated cells presented the characters of ESCs. Then the isolated cells were able to differentiate into neurocytes in vitro. Conclusion Mouse embryonic stem cells isolation, culture and differentiation system has been established. 相似文献
4.
In this study, the anti-tumour activity of selenium-protein polysaccharide (SPP), a water extract of the rich selenium Agaricus blazei, was tested both in vivo and in vitro. The results of in vivo experiments show that SPP at doses of 50 and 100 mg/kg inhibits proliferation of implanted Sarcoma 180 by 22 and 37.69%, respectively, and promotes lymphocyte transformation and natural killer (NK) cells activity in tumour bearing mice. During the in vitro experiment, we treated the tumour and non-tumour bearing mice with SPP, and prepared serum treated with SPP (SerumSPP). The results show that SerumSPP, whether from tumour or non-tumour bearing mice, significantly inhibits K562 cells proliferation and induces their apoptosis, and also significantly increases caspase-3 activity of K562 cells. However, the difference in anti-tumour activity of SerumSPP between tumour and non-tumour bearing mice is significantly different (p<0.01). The results, according to the studies both in vivo and in vitro, imply that SPP extracted from rich selenium A. blazei can inhibit growth of implanted Sarcoma 180 and promote lymphocyte transformation and NK cells activity in vivo. Additionally, SerumSPP can inhibit proliferation and cause apoptotic morphological changes and the fragmentation of internucleosomal DNA, and increase caspase-3 activity of K562 cells in vitro, which indicates that apoptosis of K562 cells induced by SerumSPP may be related to up-regulation of caspase-3. 相似文献
5.
Recent studies have identified genes that influence the length of the circadian period maintained by mice housed under constant lighting conditions. However, a less studied circadian activity variable is the amplitude of daily oscillations in locomotor activity. This parameter reflects spontaneous activity exhibited under standard lighting and housing conditions and, therefore, differs conceptually from assessments of exploratory or open-field activity, voluntary wheel-running, or circadian period during exposure to constant light or constant darkness conditions. We recently observed a greater daily amplitude of oscillation in spontaneous locomotor activity in C57BL/6 mice compared to BALB/cBy mice. To identify genetic loci with potential linkage to circadian variation in the amount of locomotor activity, we measured the spontaneous activity of 13 CXB recombinant inbred (RI) strains of mice. The probability density distributions of locomotor activity phenotypes for the 13 CXB RI strains were consistent with the presence of a low number of major quantitative trait loci affecting this trait. Regions of chromosomes 3, 8, 12, 13, and 19 showed provisional linkage to strain variation in locomotor activity. Probabilities of linkage were not sufficient for declaration of an activity-related quantitative trait locus but were sufficient to warrant further analysis either with additional RI strains or with F2 panels. 相似文献
6.
Mice of the BALB/c strain are widely used in behavioral research in spite of the albino condition, which can obscure brain-behavior relationships. We have developed a pigmented BALB strain, congenic to BALB/c, which could be more appropriate for neurogenetic studies that aim at identifying the effects of neurological mutations on behavior. Comparison of inbred albino and pigmented congenic BALB arising from the same litters provides a valuable tool for detecting the consequences of the albino mutation on behavioral performances. Preliminary results presented here show that the albino condition does not interfere with the development and patterns of connectivity of mossy fibers in the hippocampus. On the other hand, obvious coat color-linked differences appear for locomotor activity and defecation scores in the open field, pigmented mice being unexpectedlyl less active and more reactive than albino, as if better vision increased their reactions to a novel, anxiogenic environment. Finally, pigmented mice do not show better performances in the radial maze, which confirms that the inability of BALB mice for spatial learning in a highly demanding version of this task cannot be attributed to their inability to process visual information. 相似文献
7.
Primary respiratory syncytial virus infection in mice 总被引:22,自引:0,他引:22
A mouse model of respiratory syncytial virus (RSV) infection is described. A high-titered, large-volume inoculum results in replication of RSV to a high titer in lungs of BALB/c mice. Mice older than 15 weeks of age are more susceptible to RSV infection. Titers up to 10(6.9) plaque-forming units (pfu)/gram lung can be attained in 32-week-old mice. Older mice experience a clinical illness manifested by ruffled fur, reduced activity, and weight loss. Lung histology of older mice infected with RSV shows bronchiolitis and increased number of lymphocytes and macrophages in alveolar spaces compared with that of mice less than 8 weeks old. This model will serve as the basis for investigating immunodeterminants of recovery and protection from RSV infection. 相似文献
8.
Complex pattern of Th1 and Th2 activation with a preferential increase of autoreactive Th1 cells in BALB/c mice with proteoglycan (aggrecan)-induced arthritis 总被引:2,自引:0,他引:2
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Holló K Glant TT Garzó M Finnegan A Mikecz K Buzás E 《Clinical and experimental immunology》2000,120(1):167-173
The central role of CD4+ T cells and the balance between T helper (Th) subpopulations in the pathogenesis of autoimmune diseases have been extensively studied. Proteoglycan (aggrecan)-induced arthritis (PGIA) is a murine model for rheumatoid arthritis (RA), which is characterized by a Th1 dominance at the onset of the disease. In addition to CD4+ T cells, antigen-presenting B cells and autoantibodies seem to play an important role in the development and regulation of PGIA. To identify proteoglycan-specific CD4+ T cell subsets and Th1- and Th2-supported antibody isotypes during the progression of PGIA, spleen cells of proteoglycan-immunized BALB/c mice were harvested at different times of immunization, and at different stages of the disease, and their cytokine production and antigen-specific antibody isotype profiles were determined by enzyme-linked immunospot (ELISPOT) assays. Both Th1 and Th2 cytokine-producing cells, with the predominance of IL-4/IL-5-secreting cells, were detected during the prearthritic stage, and a shift toward a Th1 dominance was observed at the time of onset of arthritis. Tissue homogenates of acutely inflamed joints contained significantly higher levels of interferon-gamma than IL-4. The prearthritic period and both the acute and chronic phases of joint inflammation were characterized by IgG1 dominance in the sera and this correlated with the number of IgG1-secreting B cells in the spleen. However, the ratio of autoreactive IgG1/IgG2a-secreting cells decreased in arthritic animals. These results indicate the activation and possible regulatory roles of both Th1 and Th2 subsets in the autoimmune process, with the necessity of a relative increase of autoreactive Th1 cells for the induction of joint inflammation. 相似文献
9.
本实验采用单标记和双标记法,分别检测4种苯并(a)芘代谢产物(anti-BPDE,syn-BPDE,3-OH-BP和9-OH-BP)对BALB/3T3细胞DNA合成和程序外DNA合成(UDS)的影响,结果表明,anti-BPDE、syn-BPDE、3-OH-BP和9-OH-BP均在不同程度上使BALB/3T3细胞DNA合成增加,但只有anti-BPDE、3-OH-BP和9-OH-BP可诱发BALB/3T3细胞的UDS,说明这些苯并(a)芘代谢产物可损伤BALB/3T3细胞的DNA,同时,这种效应与苯并(a)芘代谢产物的立体结构有关。 相似文献
10.
Edwin J. Matthews 《Methods in Cell Science》1986,10(3):157-164
Summary The BALB/c-3T3 cell transformation assay evaluates the morphologic transforming potential of test chemicals using cultured mammalian cells as targets. The assay is semiquantitative and employs a contact-inhibited clone of cells derived from the original BALB/c-3T3 mouse cell line. Transforming activity, or a focus, is recognized as a dense layer of morphologically altered cells superimposed on a monolayer of the normal cell phenotype. The induction of transforming activity in a standard assay has been reported to correlate well with the carcinogenicity of many test chemicals in rodent bioassay; however, the standard assay does not detect carcinogens of all chemical classes. This report describes an operational protocol for the standard BALB/c-3T3 cell transformation assay. In addition, it provides assay acceptance criteria and a discussion of a method to evaluate transforming activity data. 相似文献