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31.
AIM:To investigate the regulatory role of nuclear factor κB (NF-κB) in the expression of interleukin-6 in mesangial cells (MC) induced by interleukin-1β.METHODS:Activation of NF-κB was measured by electrophoresis mobility shift assay (EMSA). RT/PCR and ELISA were used to detect IL-6 mRNA expression and IL-6 production, respectively.RESULTS:rhIL-1β could rapidly stimulate the activation of NF-κB in MC, and increase the expression of IL-6 mRNA and protein. PDTC, one of the inhibitor of NF-κB, could inhibit the expression of IL-6 in mRNA and protein in MC stimulated by rhIL-1β.CONCLUSION:IL-6 expression induced by IL-1β may be regulated by NF-κB in MC, NF-κB may modulate the immune-inflammatory reaction in glomerular disease.  相似文献   
32.
去毒桐籽粕饲用价值的探讨   总被引:2,自引:0,他引:2  
桐籽粕含有多种醇、二萜脂等有毒物质,因而长期以来只能用于肥料。桐籽粕中含代谢能5.46MJ/kg,粗蛋白质约36.13%,赖氨酸1.43%及较多的铁。小白鼠、肉用仔鸡饲养试验及屠宰测定试验表明:在肉用仔鸡前期日粮中加入5%~8%的桐籽粕,虽然略逊于优质蛋白质饲料,但作为中、低档蛋白质饲料资源,仍具有开发价值。  相似文献   
33.
古玉  王之阳  马晓平  邬儒恩 《安徽农业科学》2012,(12):7104-7105,7353
[目的]通过过山青对小鼠的急性毒性试验,确定过山青水提取物短期内使用有无毒性。[方法]将不同浓度的过山青灌喂小鼠后,连续观察10 d,记录小鼠体征及活动情况,并检测小鼠的肝肾功能和血常规。[结果]过山青水提物对小鼠的血常规中白细胞的影响大,但没有线性关系,高低计量影响相对较小,而中剂量的影响却很大。过山青水提物对淋巴细胞和单核细胞的影响不大,对中性粒细胞的影响比较大,对红细胞的影响,除D组外,影响较小,对血红蛋白的影响也不明显。过山青对小鼠体征及活动情况无明显影响,使血液中白细胞和中性粒细胞降低,导致免疫功能下降;较大剂量时导致肝脏毒性,对肾脏的影响不明显。[结论]过山青水提取物对小鼠有一定的毒理作用,较大剂量时毒性较大。  相似文献   
34.
[目的]研究速溶芦笋粉对小鼠免疫功能的影响。[方法]根据《保健食品检验与评价技术规范》(2003年版)的方法,将速溶芦笋粉(芦笋提取物)对小鼠进行灌胃给药,持续30 d,检验其对小鼠免疫能力的影响。[结果]速溶芦笋粉能明显增强小鼠细胞免疫和体液免疫能力,也能明显增强小鼠单核-巨噬细胞功能和NK细胞活性,但对各剂量组小鼠体重及脾脏和胸腺的脏器指数无明显影响。[结论]速溶芦笋粉具有增强免疫力的功能。  相似文献   
35.

Background

The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells.

Methods

A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses.

Results

Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles.

Conclusion

We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated.  相似文献   
36.
AIM: To study the regulatory effect of nitric oxide on the lymphatic stomata and probe into the mechanism of ultrafiltration failure during long-term peritoneal dialysis(PD). METHODS: ①Sodium nitroprusside(SNP) and NG-monomethyl-L-arginine(L-NMMA)(inhibitor of nitric oxide synthase(NOS)) were injected into the peritoneal cavity of the mouse model of PD. ②NO concentration was measured in serum. ③The lymphatic stomata was studied with SEM and computer image processing.RESULTS: During PD, a lot of macrophages wandered out of the lymphatic stomata to form milky spots on the peritoneal mesothelium, and the diameter and density of the stomata were increased with NO concentration raised. After PD cessation, the stomata was normal gradually and numbers of milky spots reduced with NO concentration fall. The diameter and density of the stomata were increased with a rise in NO concentration as SNP was used, oppositely those were decreased with the increase in NO concentration as L-NMMA was injected intraperitoneally. CONCLUSIONS: The lymphatic stomata might be regulated through increasing the endogenous NO concentration. During PD, NO is increased gradually and the ultrafiltration failure would occur when re-absorption of the stomata was increased from the peritoneal cavity.  相似文献   
37.
肺气虚证小鼠模型造模方法及其对小鼠免疫功能的影响   总被引:1,自引:0,他引:1  
为筛选肺气虚证小鼠模型最佳造模方法并验证其免疫功能变化,分别选用SO2法、SO2+寒冷因素刺激法、香烟烟熏法和香烟烟熏+寒冷因素刺激法重建肺气虚证小鼠模型,检测其体重、肺脏剖检及病理组织变化等指标,筛选最佳造模方法,并测定其腹腔巨噬细胞活性、体外B细胞抗体分泌能力、血清NO含量、淋巴细胞增殖能力及细胞因子IL-2、IL-4、IL-6、IL-10、IFN-γ、TNF-α含量、肺匀浆中sIgA、sIgM水平。结果显示,香烟烟熏+寒冷因素刺激法小鼠造模完成后出现严重的肺出血、肺组织坏死及炎性细胞浸润等病变,且与对照组小鼠相比,其体重、脾脏指数、胸腺指数分别显著下降18.35%,37.12%,19.69%,肺脏指数显著升高12.73%;小鼠腹腔巨噬细胞活性(P<0.01)、血清NO水平下降(P<0.05);T、B淋巴细胞增殖能力显著升高;细胞因子IL-2(P<0.01)、IFN-γ、IL-4含量升高(P<0.05),IL-6含量下降(P<0.05);sIgA、sIgM水平均极显著升高。表明,香烟烟熏+寒冷因素刺激法是肺气虚小鼠模型最佳造模方法,且其免疫功能受损。  相似文献   
38.
Mice infected with Trypanosoma congolense developed a severe anaemia 1 week after infection, which persisted till treatment with diminazine aceturate when the packed cell volume (PCV) recovered to pre-infection levels. This was accompanied by a marked increase in the plasma levels of the acute phase proteins (APP), serum amyloid P-component (SAP) and haptoglobin (Hp). The initial peak levels of Hp and SAP were attained 7 and 12 days post-infection (DPI), respectively. Thereafter SAP levels decreased significantly to near pre-infection levels, but later increased even after treatment to give a second peak 34 DPI after which there was a decline till the study was terminated. The Hp levels on the other hand decreased to an intermediate level after the initial peak increasing to a second peak 22 DPI. Thereafter Hp decreased significantly following diminazine aceturate treatment to reach pre-infection levels within 5 days post-treatment. This indicates that T. congolense-infected mice develop severe anaemia accompanied by an acute phase response leading to an increase in SAP and Hp but that following treatment divergent responses occurred indicating differences in the pathways for stimulation of the APP. Haptoglobin was shown to be an earlier indicator of infection and a better marker in monitoring the response to treatment.  相似文献   
39.
桑椹素对老龄小鼠肾阳虚症状的疗效试验   总被引:2,自引:1,他引:1  
为进一步开发桑椹的药用保健功能,研究了桑椹素对老龄肾阳虚小鼠肾损伤的保护作用,并对其机制进行了探讨。将雄性老龄小鼠随机分为正常组和模型组,桑椹素低、中、高剂量组(0.1、0.2、0.4 g/kg)和补肾填精丸组(0.35 g/kg),测定小鼠血清、肾脏一氧化氮(NO)含量变化,观察小鼠肾脏组织结构病理变化。结果表明,模型小鼠以0.2、0.4 g/kg剂量桑椹素灌胃可明显改善肾阳虚症状,显著提高血清、肾脏NO含量,减轻氢化可的松引起的肾脏损害。其作用机制之一可能是通过提高肾脏NO的合成,增加肾血流量和肾小球滤过率,从而减轻对肾脏的损害。  相似文献   
40.
[目的]优化飞机草总黄酮提取工艺,并研究飞机草总黄酮提取物对小鼠的急性毒性。[方法]以飞机草总黄酮提取率为关键指标,采用超声波辅助乙醇溶剂提取法,通过单因素试验和正交试验设计,对提取时间、提取温度、料液比、乙醇浓度等提取条件进行优化,筛选飞机草总黄酮提取的最佳工艺;以昆明种小鼠为试验动物,进行飞机草总黄酮提取物口服急性毒性试验,测定半数致死LD50和最大耐受量。[结果]飞机草总黄酮的最佳提取工艺为提取时间5 h、提取温度70℃、料液比1∶60(g∶m L)、乙醇浓度70%,飞机草总黄酮提取率为7.13%;飞机草总黄酮提取物对昆明种小鼠的口服LD50未测得,其小鼠口服最大耐受量为80 000 mg/kg。[结论]飞机草总黄酮属于实际无毒物质。  相似文献   
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