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51.
The idea has been popular for a long time that Th1/Th2 imbalance is the major cause of many diseases. However, the Th1/Th2 paradigm has encountered increasing challenge since the discovery of a novel subset of Th cells, Th17. Th17 cells secrete a series of cytokines (IL-17A~F, IL-21 and IL-22), which is quite different from those produced by Th1 and Th2 cells. It is now generally accepted that Th17/IL-17A plays a pivotal role in autoimmune and host defense. Although first discovered in autoimmune diseases, emerging studies begin to explore the way in which Th17/IL-17A acts in chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmanary disease. In this review, we will summarize the differentiation and function of Th17, and introduce the progress in the correlation between Th17/IL-17A and chronic inflammatory airway diseases. Further elucidating the mechanism of Th17/IL-17A-related pathophysiological changes will contribute to prevention and treatment of chronic inflammatory airway diseases.  相似文献   
52.
研究破格救心汤对慢性心力衰竭(CHF)大鼠血小板膜糖蛋白ⅡbⅢa(GP-ⅡbⅢa)浓度的影响,探讨其治疗CHF的作用机制。采用阿霉素诱导法复制CHF大鼠模型,随机分为空白组、模型组和破格救心汤组。记录各组大鼠死亡情况和一般情况,并运用ELISA试剂盒检测各组大鼠的GP-ⅡbⅢa浓度。模型组大鼠死亡4只,破格救心汤组和空白组无死亡。模型组大鼠出现鼻唇紫绀、四肢末梢苍白、被毛粗糙变黄、进食减少、行动缓慢等。与模型组比较,破格救心汤组大鼠症状明显减轻,GP-ⅡbⅢa浓度明显降低(P<0.01)。破格救心汤能降低心衰大鼠GP-ⅡbⅢa浓度,减少血栓栓塞性疾病的发生率,这可能是其治疗CHF的作用机制之一。  相似文献   
53.
目的:观察急性白血病化疗患者应用力素(二丁酰环磷腺苷钙)对化疗药物急性心脏毒性的影响。方法:将初治急性白血病患者58例分成治疗组(n=28)和对照组(n=30)两组,治疗组在普通化疗方案的基础上加用力素治疗,对照组仅用普通化疗方案治疗.观察两组第二疗程化疗后心肌酶的变化、心力衰竭的发生情况.平均心率及心电图ST段的变化。结果:两组的心肌酶(磷酸肌酸激酶、乳酸脱氢酶及α羟丁酸脱氢酶)、平均心率、心电图ST段的下移的程度差异均有显著性(P〈0.01或0.05);但两组的心力衰竭发生情况差异无显著性(P〉0.05)。结论:力素能够减轻化疗药物对急性白血病化疗患者的急性心脏毒性。  相似文献   
54.
Increased numbers of tumour‐associated macrophages correlate with rapid tumour growth and metastasis in tumours. Thus, macrophage depletion has potential as a novel cancer therapy and positive responses have been reported in rodent tumour models. To investigate the effectiveness of this approach in dogs with cancer, we evaluated the effects of the macrophage‐depleting agent liposomal clodronate (LC) in dogs with soft‐tissue sarcoma (STS). To this end, we conducted a clinical trial of LC therapy in 13 dogs with STS. Repeated LC administration was well tolerated clinically. Preliminary examination of tumour biopsy sets from 5 of the 13 dogs demonstrated that the density of CD11b+ macrophages was significantly decreased after LC treatment. Circulating concentrations of interleukin‐8 were also significantly reduced. These preliminary studies are the first to suggest that LC can be used as a systemic macrophage‐depleting agent in dogs to reduce numbers of tumour‐associated macrophages.  相似文献   
55.
Alveolar macrophages (AMs) constitute the first line of defence in the lung of all species, playing a crucial role in the regulation of immune responses to inhaled pathogens. A detailed understanding of the function and phenotype of AMs is a necessary pre-requisite to both elucidating their role in preventing opportunistic bacterial colonisation of the lower respiratory tract and developing appropriate preventative strategies. The purpose of the study was to characterise this important innate immune cell at the tissue level by making functional and phenotypic comparisons with peritoneal macrophages (PMs). We hypothesised that the tissue of origin determines a unique phenotype of AMs, which may constitute an appropriate therapeutic target for certain equine respiratory diseases. Macrophages isolated from the lung and the peritoneal cavity of 9 horses were stimulated with various toll like receptor (TLR) ligands and the production of nitrite, tumour necrosis factor alpha (TNFα), interleukin (IL) 10 and indoleamine 2,3-dioxygenase (IDO) were measured by the Griess reaction and enzyme linked immunosorbent assay (ELISA) and/or quantitative polymerase chain reaction, respectively. Cells were also compared on the basis of phagocytic-capacity and the expression of several cell surface markers. AMs, but not PMs, demonstrated increased TNFα release following stimulation with LPS, polyinosinic polycytidylic acid (Poly IC) and heat-killed Salmonella typhinurium and increased TNFα and IDO mRNA expression when stimulated with LPS. AMs showed high expression of the specific macrophage markers cluster of differentiation (CD) 14, CD163 and TLR4, whereas PMs showed high expression of TLR4 only. AMs, but not PMs, demonstrated efficient phagocytic activity. Our results demonstrate that AMs are more active than PMs when stimulated with various pro-inflammatory ligands, thus supporting the importance of the local microenvironment in the activation status of the macrophage. This information provides a valuable knowledge base on which to improve our understanding of the role of macrophages and their microenvironment in equine innate immunity.  相似文献   
56.
57.
为分析髓细胞瘤型J亚群禽白血病病毒(ALV-J)地方分离毒株的分子特征及开展该病毒的反向遗传操作研究,本试验从四川某肉种鸡场髓细胞瘤病变病鸡的组织中分离到1株髓细胞瘤型ALV-J,命名为SCGS-1.序列测定表明其前病毒cDNA全序列长7 499 bp,与其他ALV-J代表毒株序列相似性均为95%~99%.在所有基因中,其env基因和LTR序列与其他毒株相应序列同源性相对较低,env基因同源性为93.0%~99.5%,LTR基因同源性为92%~95%,pol基因同源性为97%~99%,gag基因同源性为94%~97%.根据该毒株序列和质粒pUC19的序列,将SCGS-1株前病毒cDNA全序列分3段克隆入pUC19中,构建含SCGS-1前病毒cDNA的重组载体并命名为pUC-SCGS.试验结果为研究ALV-J的进化规律和开展反向遗传操作打下基础.  相似文献   
58.
In vivo visualization of kidney and liver damage by Magnetic Resonance Imaging (MRI) may offer an advantage when there is a need for a simple, non-invasive and rapid method for screening of the effects of potential nephrotoxic and hepatotoxic substances in chronic experiments. Here, we used MRI for monitoring chronic intoxication with microcystins (MCs) in rat. Male adult Wistar rats were treated every other day for eight months, either with MC-LR (10 μg/kg i.p.) or MC-YR (10 μg/kg i.p.). Control groups were treated with vehicle solutions. T1-weighted MR-images were acquired before and at the end of the eight months experimental period. Kidney injury induced by the MCs presented with the increased intensity of T1-weighted MR-signal of the kidneys and liver as compared to these organs from the control animals treated for eight months, either with the vehicle solution or with saline. The intensification of the T1-weighted MR-signal correlated with the increased volume density of heavily injured tubuli (R2 = 0.77), with heavily damaged glomeruli (R2 = 0.84) and with volume density of connective tissue (R2 = 0.72). The changes in the MR signal intensity probably reflect the presence of an abundant proteinaceous material within the dilated nephrons and proliferation of the connective tissue. T1-weighted MRI-is a valuable method for the in vivo screening of kidney and liver damage in rat models of intoxication with hepatotoxic and nephrotoxic agents, such as microcystins.  相似文献   
59.
【目的】探索tva受体基因起始密码子突变(tva c.3G>A)对鸡感染A亚群禽白血病病毒(Avian leukemia virus subgroup A, ALV-A)的影响。【方法】利用Sanger测序和RT-PCR验证我国黄羽肉鸡存在tva c.3G>A突变。利用流式细胞术检测tva c.3G>A突变对鸡体外感染RCASBP(A)-GFP荧光报告病毒的影响。通过ALV-A体内攻毒试验,探究tva c.3G>A突变对鸡体内感染ALV-A的影响。利用直接测序方法对我国黄羽肉鸡品系tva c.3G>A突变位点进行基因分型。【结果】Sanger测序和RT-PCR结果鉴定我国黄羽肉鸡品系tva基因编码区第3位碱基由G突变为A,该突变引起tva基因起始密码子序列由ATG突变为ATA。流式细胞术检测结果显示野生型tva c.3G/G鸡胚成纤维细胞(Chicken embryo fibroblast, CEF)对RCASBP(A)-GFP易感,纯合突变型tva c.3A/A CEF抗RCASBP(A)-GFP感染,表明tva c.3G>A突变导致鸡体外抗RCA...  相似文献   
60.
The present study aimed to investigate the effect of relative humidity(RH) at either acute or chronic moderate ambient temperature(Ta) on growth performance and droppings' corticosterone metabolites of broilers.Two experiments were conducted: effect of RH(35,60 or 85%) on average daily feed intake(ADFI) and droppings' corticosterone metabolites at acute(1 d: 20–26 or 31–20°C,26 or 31°C for 6 h d–1 at 10:00–16:00) moderate Ta(experiment 1) and effect of RH(35,60 or 85%) on growth performance and droppings' corticosterone metabolites at chronic(step-wisely increasing temperature by 3°C every 3 d from 20 to 32°C within 15 d: 20–23–26–29–32°C) moderate Ta(experiment 2).Droppings were collected at the 2,4,6,8,and 22 h after Ta-RH controlled in experiment 1 and at the 2,4,6,and 22 h after Ta controlled to 32°C in experiment 2.The results showed that: 1) In experiment 1,85% RH increased(P0.05) the droppings' corticosterone metabolites at the 2,6,8,and 22 h and 35% RH increased(P0.05) it at the 2 and 22 h compared to the 60% RH.Moreover,85% RH further increased(P0.05) it compared to the 35% RH,however,no difference(P0.05) was found in ADFI among the three RH groups at acute moderate 26°C; 35 and 85% RH increased(P0.05) droppings' corticosterone metabolites at the 2,6,8 and 22 h and decreased(P0.05) ADFI compared to the 60% RH,moreover,85% RH further increased(P0.05) droppings' corticosterone metabolites and further decreased(P0.05) ADFI compared to the 35% RH at acute moderate 31°C; and the average of droppings' corticosterone metabolites in the whole period had a negative correlation(P0.02) with the ADFI.2) In experiment 2,85% RH increased(P0.01) droppings' corticosterone metabolites only at the 2 h and decreased(P0.02) ADFI and average daily gain(ADG) compared to the 60% RH,no difference(P0.05) in droppings' corticosterone metabolites was found between the 35 and 60% RH,however,35% RH decreased(P0.01) ADG compared to the 60% RH,and the average of droppings' corticosterone metabolites in the whole period also had a negative correlation(P0.02) with ADFI and ADG.In conclusion,droppings' corticosterone metabolites could be used as a RH stress index and low and high RH,especially high RH,reduced growth performance possibly through inducing RH stress at moderate temperature.  相似文献   
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