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71.
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   
72.
Electrochemotherapy is a novel antitumor treatment involving the systemic administration of bleomycin followed by the delivery of electrical pulses to the tumor. The present study investigates the effects of electrochemotherapy on the growth of colon 26 cells inoculated subcutaneously into the backs of BALB/c mice. The mice were divided into the following four experimental groups: 20 that received no further treatment after the inoculation of colon 26 cells (control group); 20 that received 500 μg of bleomycin intraperitoneally 7 and 9 days after the inoculation (BLM group); 20 that received electric pulses to the tumor 7 and 9 days after the inoculation (EP group); and 30 that received electrochemotherapy 7 and 9 days after the inoculation (ECT group). During 28 days of observation, no deaths due to tumor progression occurred in the ECT group, but there were 18 in the control group, 11 in the BLM group, and 18 in the EP group. While weight loss was observed in all groups, it was most remarkable in the control group. Tumor growth was significantly inhibited in the ECT group, compared to the other experimental groups (P<0.01). The results of this study demonstrated that electrochemotherapy significantly inhibited the growth of colon 26 tumors in mice, without causing any remarkable adverse effects.  相似文献   
73.
邻甲苯胺经口半数致死量为755mg/kg,属低毒类。动物染毒邻甲苯胺19mg/kg以上引起小鼠脾脏增大,38mg/kg以上引起白细胞计数升高,且淋巴细胞百分比升高,各染每剂量对小因清免疫球蛋白IgG含量和巨噬细胞吞噬功能无明显影响。结果表明,邻甲苯胺对造血系统有影响,对免疫系统无明显直接影响。  相似文献   
74.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them.  相似文献   
75.
中药白芍水煎剂给予老龄小鼠灌胃(10g/kg),每日一次,连用4周。采用邻苯三酚自氧化法、DTNB和TBA比色法测定红细胞超氧化物歧化酶(SOD)活性,全血谷胱甘肽过氧化物酶(GSH-Px)活力和红细胞中及血浆中MDA含量。结果表明,白芍水煎剂能显著增强老龄小鼠红细胞SOD活性、全血GSH-Px的活力,而且可显著降低红细胞和血浆中MDA含量,故具有延缓衰老作用。  相似文献   
76.
S. WAKI 《Parasite immunology》1994,16(11):587-591
The effects of administrating recombinant human granulocyte colony-stimulating factor (rhG-CSF) and passively transferring immune serum on infection with an attenuated variant of Plasmodium berghei XAT (Pb XAT), in severe combined immunodeficiency (SCID) mice were examined. In immune competent (C.B-17) mice, the attenuated parasite infection was inevitably self-resolving and degenerating forms inside erythrocytes appeared, coinciding with the drop in parasitaemia, whereas SCID mice were unable to control parasite growth and all the mice died. Continuous administration with rhG-CSF caused neutrophilic granulocytosis in both SCID and C.B-17 mice. The effect of rhG-CSF on the infection in C.B-17 mice was to suppress the course of the parasitaemia at an early phase whereas it had no effect in SCID mice. When immune serum was transferred on the day of infection, the prepatent period was prolonged two days in both SCID and C.B-17 mice. When administration with rhG-CSF was combined with transfer of immune serum, SCID mice showed four days delay in patency and degenerating parasites were seen during the course of parasitaemia, although the infection was ultimately fatal. C.B-17 mice similarly treated showed a seven day delay in the onset of the patent parasitaemia which was of a lesser magnitude and shorter in duration compared with control mice. On the other hand, when C.B-17 mice were splenectomized three weeks before infection and then treated with rhG-CSF and immune serum, no degenerating parasites were seen during the infection and all mice died with high parasitaemias. These results show that antibody-dependent neutrophil-mediated parasite killing may occur in the spleen of mice infected with P. berghei XAT.  相似文献   
77.
反义局部粘着斑激酶抑制肝癌侵袭生长的研究   总被引:4,自引:1,他引:3  
目的 观察反义局部粘着斑激酶 (FAK)脱氧寡核苷酸 (ODN)转染对Bel740 2肝癌移植瘤侵袭性生长的影响 ,并探讨其作用机制。方法 以LipofectAMINE介导的反义FAKODN转染Bel 740 2肝癌细胞株后 ,于 6只裸鼠双侧颈背部、髋部共 4处皮下接种 ,观察移植瘤生长情况 ,并行肿瘤微血管密度 (MVD)的免疫组织化学检测及MMP2与TIMP2表达的逆转录 聚合酶链反应(RT PCR)检测。结果 反义FAKODN转染使裸鼠皮下移植瘤的生长受到显著抑制 ,抑瘤率为3 5 .7% ;MVD在反义转染组 ( 9.5 99± 1.2 84)显著低于对照组 [( 13 .915± 2 .618) ,P <0 .0 5 ] ;MMP2表达在反义转染组 ( 0 .199± 0 .0 61)显著低于对照组 ( 0 .42 1± 0 .118) ,TIMP2表达在反义转染组( 0 .461± 0 .15 3 )则显著高于对照组 [( 0 .2 98± 0 .10 4) ,P <0 .0 5 ]。结论 信号转导分子FAK表达阻断可显著抑制Bel 740 2肝癌细胞株在裸鼠体内的侵袭性生长 ,病理性肿瘤血管生成减少及MMP2、TIMP2表达改变与其抗肿瘤作用密切相关。  相似文献   
78.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用.  相似文献   
79.
Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection.  相似文献   
80.
We describe an ELISA for trophozoite-specific IgA in the intestinal secretions of mice infected with Giardia muris. Using this method, trophozoite-specific IgA was demonstrated in intestinal secretions of Giardia-infected immunocompetent BALB/c mice. Such antibody was undetectable in the intestinal secretions of Giardia-infected athymic (nude) mice. Immunocompetent BALB/c mice are able to clear G. muris infection whereas nude mice are not. The study provides evidence that the chronicity of G. muris infection in nude mice results from lack of intestinal trophozoite-specific IgA in these animals. By means of the ELISA, trophozoite-specific IgA was demonstrated in intestinal secretions from immunocompetent mice in the absence of protease inhibitors.  相似文献   
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