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991.
目的 :构建弓形虫致密颗粒抗原 1 (GRA1 )真核表达质粒 ,为进一步开展DNA疫苗的保护性研究打下基础。方法 :采用PCR扩增出编码GRA1目的基因 ,用EcoRⅠ /XhoⅠ分别对扩增产物和真核表达质粒pcDNA3进行双酶切 ,将GRA1定向克隆到pcDNA3EcoRⅠ /XhoⅠ位点 ;对重组质粒进行PCR ,双酶切初步鉴定后做序列测定。结果 :特异扩增出预计的GRA1片段 ,大小为 5 73bp ;扩增产物双酶切后成功连接到pcDNA3中 ,经PCR ,双酶切及序列测定结果表明重组质粒中含有GRA1读框。结论 :成功构建弓形虫GRA1真核表达质粒。  相似文献   
992.
Microorganisms are very powerful tools for the supply of information about the toxic effects of lipophilic compounds, since an impairment of cell growth usually occurs as a result of perturbations related, in most cases, with the partition of toxicants in membranes. The thermophilic eubacterium Bacillus stearothermophilus has been used as a model system to identify α- and β-endosulfan interactions with the membrane possibly related with the insecticide toxicity. Two approaches have been pursued: (a) bacterial growth is followed and the effects of endosulfan isomers determined; (b) biophysical studies with the fluorescent fluidity probe 1,6-diphenyl-1,3,5-hexatriene (DPH) were performed to assess the effects of α- and β-endosulfan on the organization of the membrane lipid bilayer. The effects on growth were quantitatively evaluated by determination of growth parameters, namely the lag phase, the specific growth rate and the cell density reached by cultures in the stationary phase. Growth inhibition by α and β-endosulfan dependent on the concentration is diminished or removed by the addition of 2.5 m Ca2+ to bacterial cultures. Fluorescence DPH polarization consistently showed opposite effects of Ca2+ and α- and β-endosulfan on the physical state of bacterial polar lipid dispersions.  相似文献   
993.
目的 探讨昆明山海棠(THH)碱对Jurkat T淋巴瘤细胞的细胞毒性、细胞周期和凋亡时相特异性的影响,以了解THH碱诱导细胞凋亡的机制。方法 台盼蓝染色法检测细胞生长和细胞活力;DNA染色法、TUNEL标记结合流式细胞术检测细胞周期和凋亡时相特异性。结果 THH碱能有效抑制Jurkat细胞增殖、细胞活力下降,细胞在增殖周期中被阻滞于G1期。THH碱首先能诱导S、C2/M期细胞凋亡,同时能诱导G1期细胞凋亡。结论 提示THH碱能抑制Jurkat细胞的DNA合成,抑制细胞增增殖,并可显著诱导各期相细胞发生凋亡。  相似文献   
994.
目的探讨精神分裂症的外周神经免疫机制及其与临床症状的关系。方法检测精神分裂症患者致炎性细胞因子白介素-1β(IL-1β)、肿瘤坏死因子-α(TNF—α)以及酪氨酸羟化酶(TH)的mRNA表达水平,采用逆转录-聚合酶链反应及半定量检测技术,分别检测39例精神分裂症患者(患者组)、25例同胞(同胞组)及30名正常对照(对照组)外周血单个核细胞(PBMC)IL-1β、TNF-α及TH基因表达水平,同时应用阳性和阴性症状量表(PANSS)评定精神分裂症患者临床症状。结果患者组、同胞组及对照组IL-1β的mRNA表达水平分别为1.52±1.01、1.52±1.09和0.74±0.38;TNF—α的mRNA表达水平分别为1.18±0.99、1.01±0.87和0.70±0.29;TH的mRNA表达水平分别为0.55±0.33、0.61±0.32和0.28±0.20。患者组和同胞组的IL-1β、TNF—α、TH的mRNA表达水平均明显高于对照组(P〈0.05或P〈0.01)。患者组IL-1β(r=0.420)、TNF—α(r=0.430)的mRNA表达水平与PANSS的-般病理症状分呈正相关(P〈0.01)。同胞组与对照组合并统计,IL-1β与TNF-α的mRNA表达水平呈正相关(r=0.847,P〈0.01);IL-1β与TH的mRNA表达水平呈正相关(r=0.666,P〈0.01)。患者组仅IL-1β与TNF—α的mRNA表达水平呈正相关(r=0.942,P〈0.01)。结论精神分裂症患者PBMC细胞TH、IL-1β和TNF—α的mRNA表达水平高于正常,且与精神分裂症的-般病理症状显著相关。  相似文献   
995.
Objective and design Previously it was shown that blocking of the renin-angiotensin system (RAS) by angiotensin converting enzyme (ACE) inhibitors, or suppression of inflammatory responses by immunosuppressive drugs such as mycophenolate mofetil (MMF) could attenuate renal injury in diabetic rats. Whether RAS blockade combined with an immunosuppressive drug provides superior renoprotection against diabetic nephropathy has not been clearly delineated. Materials Diabetes was induced by injection of streptozotocin after uninephrectomy. Treatment Rats were randomly separated into five groups: control, diabetes, diabetes treated with enalapril (an ACE inhibitor, 10 mg/kg/d by gastric gavage), diabetes treated with MMF (10 mg/kg/d by gastric gavage), or diabetes treated with a combination of both agents and were followed for 8 weeks. Methods 24 h urinary albumin excretion rate (AER) was determined, renal injury was evaluated, immunohistochemistry for ED-1 macrophage marker, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1) were performed, and expression of transforming growth factor (TGF)-β1 protein was determined by Western blotting analysis. Results Diabetes was associated with a considerable increase in AER. Both enalapril and MMF retarded the increase in albuminuria, which was nearly completely abrogated by combination therapy. Increased glomerular volume and tubulointerstitial injury index in diabetic rats was attenuated by treatment with either enalapril or MMF and further reduced by the combination of the two. Elevated malondialdehyde levels in renal tissue were reduced by enalapril or MMF and, more effectively, by combined enalapril with MMF. Renal overexpression of ICAM-1 was not retarded by enalapril and attenuated by MMF or combined enalapril with MMF. Combination therapy was associated with a superior suppression of diabetes-induced macrophage recruitment and overexpression of MCP-1 and TGFβ1 compared to either monotherapy in renal tissue. Conclusion The combination of enalapril and MMF confers superiority over monotherapy in renoprotection, a mechanism which may be at least partly correlated with synergistic suppression of increased macrophage recruitment and overexpression of MCP-1 and TGF-β1 in renal tissue in diabetic rats. Received 26 July 2005; returned for revision 5 October 2005; returned for final revision 9 January 2006; accepted by M. Katori 23 January 2006  相似文献   
996.
组织型纤溶酶原激活剂及其抑制物的变化与冠心病的关系   总被引:3,自引:0,他引:3  
目的:观察冠心病患者纤溶活性的变化及其在冠心病发病中的作用,探讨其临床意义。方法:用酶联免疫双抗夹心(ELISA)法测定58例冠心病患者血浆中组织型纤溶酶原激活剂(t—PA)及纤溶酶原激活抑制物-1(PAI-1)抗原含量,反映纤溶-抗纤溶活性的变化,并对冠心病患者组与对照组纤溶指标进行不同性别间的比较。结果:急性心肌梗死、不稳定心绞痛患者PM-1的含量、PAI-1/t—PA比值明显高于对照组,且急性心肌梗死患者PM-1的含量较不稳定心绞痛患者显著为高。但t—PA在急性心肌梗死、不稳定心绞痛患者均无显著降低。患者组及对照组不同性别间纤溶及抗纤溶水平均未见有显著差异。结论:血栓性疾病与纤溶系统的异常有密切关系。纤溶系统活性的变化及纤溶-抗纤溶的平衡失调在缺血性心脏病的发生、发展中起着重要作用。  相似文献   
997.
目的 根据小鼠神经元与T淋巴细胞具有共同抗原Thy-1的特点,利用鼠脑组织制备兔抗鼠T淋巴细胞血清。方法 提取鼠脑组织与弗氏完全佐剂混合,制成油包水乳剂, 免疫2只家兔后,采血,分离血清,用鼠脾淋巴细胞做凝集试验及补体依赖的细胞毒试验确定其活性。结果 制备的抗血清可与鼠脾淋巴细胞发生反应,2只兔抗血清凝集试验的效价分别为1:640及1:1280。抗血清1:320倍稀释后与鼠脾淋巴细胞做补体依赖的细胞毒试验,特异性细胞毒性均为32%。结论 用鼠脑组织制备抗鼠T淋巴细胞血清是一种可行的方法。  相似文献   
998.
给予小鼠灌胃染毒亚砷酸钠,观察急性及亚慢性染毒后小鼠全血及组织中谷胱甘肽(GSH)水平。结果表明:在急性实验中,全血及肾脏中GSH含量逐渐增加.且呈剂量-效应关系;肝脏及心脏中GSH含量于低剂量显著增加,高剂量则显著下降;亚慢性实验中,高砷组全血GSH含量显著增加,超砷组则显著降低;肝中GSH含量从低砷组即开始降低;肾脏GSH含量仅在高砷组才开始显著降低;心脏GSH含量随染毒剂量增加而逐渐降低,并呈明显剂量-效应关系。提示不同剂量、不同时间染毒引起血液及组织中GSH含量的变化不同。  相似文献   
999.
The 5-HT1 receptor agonist, sumatriptan, is highly effective in the treatment of migraine. Some patients, however, do not respond or experience recurrence of the headache. In addition, some patients report chest symptoms after sumatriptan. We investigated whether these different responses could be attributed to genetic diversity of the 5-HT1B receptor, which most likely mediates the therapeutic action and the coronary side effects of sumatriptan. Allele frequencies of two polymorphisms in the 5-HT1B receptor gene ( G861C and T-261G ) were investigated in migraine patients with consistently good response to sumatriptan (n=14), with no response (n=12), with recurrence of the headache (n=12), with chest symptoms (n=13), and in patients without chest symptoms (n=27). Allele frequencies (G:0.74; C:0.26 at nt 861 and T:0.39; G:0.61 at nt -261) did not differ between patient groups, indicating that genetic diversity of the 5-HT1B receptor does not seem to be involved in the different clinical responses to sumatriptan.  相似文献   
1000.
胰岛素抵抗性高血压大鼠α1肾上腺素受体亚型的改变   总被引:2,自引:0,他引:2  
目的和方法:用高糖喂养复制胰岛素抵抗性高血压(insulin-resistanthypertension,IRH)大鼠模型,用放射配体结合实验和离体左心房及主动脉收缩功能实验,观察IRH大鼠α1肾上腺素受体(α1-adrenoceptor,α1-AR)及其3种亚型在心脏和主动脉的改变。结果和结论:IRH大鼠与同龄SD大鼠相比:(1)心脏α1-AR密度下降48%(P<005),而介导的正性变力效应不变。(2)心脏α1-AR3种亚型占α1-AR总数的比例和在介导心脏正性变力效应中的作用表现为α1B-AR增加,α1D-AR减少,而α1A-AR不变。(3)介导主动脉收缩的α1-AR及各亚型对激动剂的敏感性及最大收缩效应均无明显改变。  相似文献   
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