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1.
目的 探讨火把花根片对哮喘豚鼠抗炎作用机制及其对肺泡灌洗液 (BALF)白介素 5(IL 5)受体mRNA表达的影响。方法  3 2只健康豚鼠随机分为 4组 :正常对照组 ,哮喘组 ,地塞米松治疗组 ,火把花根片治疗组。后 3组制作成哮喘豚鼠模型 ,再激发用药。测定肺泡灌洗液的细胞总数和细胞分类 ,观察肺组织的病理改变 ,进行BALF的IL 5受体mRNART PCR半定量分析。结果 火把花根片治疗组BALF的嗜酸性粒细胞 (Eos)数较正常组和哮喘组 ,差异均有显著性 ,分别为P <0 0 5和P <0 0 1。肺组织病理切片 ,火把花根片组充血水肿明显 ,但Eos肺组织浸润较哮喘组有明显减少。BALF的IL 5受体mRNART PCR半定量分析显示 ,火把花根片治疗组与地塞米松治疗组差异无显著性 ,P >0 0 5,但和正常组与哮喘组比较差异有显著性 ,P <0 0 1。结论 火把花根片能抑制哮喘豚鼠的气道炎症 ,为临床治疗哮喘提供初步的理论基础  相似文献   
2.
目的:对比分析小切口非超声乳化白内障摘除术与超声乳化白内障吸除术的临床应用效果。

方法:选取2010-03/2013-02收治的老年性白内障患者93例124眼随机分为两组,42例59眼行小切口非超声乳化白内障摘除术(SICS组),51例65眼行超声乳化白内障吸除术(Phaco组),比较两组患者术后视力、角膜散光、手术源性散光及术中、术后并发症。

结果:术后1d; 1wk两组患者视力≥0.5分别为SICS组38眼(64.4%),41眼(69.5%),Phaco组29眼(44.6%),32眼(49.2%),SICS组的视力优于Phaco组(χ2=4.877,5.243,P<0.05)。术后1,3mo两组视力≥0.5眼数比较差异无统计学意义(χ2=0.005,0.085,P>0.05)。平均角膜散光采用重复测量设计方差分析:组内比较不同时间有统计学意义(F=25.624,P<0.05),且有随时间降低的趋势; 组间比较无统计学意义(F=0.986,P>0.05),两组患眼术后1wk平均角膜散光较术前增大,差异有统计学意义(t=2.906,2.427,P<0.05)。术后1wk; 1mo Phaco组手术源性散光SIA均低于SICS组(t=-4.628,2.770,P<0.05),术后3mo两组SIA对比差异无统计学意义(t=0.754,P>0.05), 组内比较和组间比较不同时间的SIA均有统计学意义(F=26.37,P<0.05,F=14.29,P<0.05)。两组患者术中后囊膜破裂、术后角膜水肿、前房色素膜反应对比差异无统计学意义。

结论:小切口非超声乳化白内障摘除术与超声乳化白内障吸除术对比,两种手术术后效果相近,对于白内障的治疗方案选择,白内障超声乳化手术并非唯一最佳手术方案,在缺少超乳设备的边远地区,选择小切口非超声乳化手术同样可以达到与超乳手术接近的术后视觉效果。  相似文献   

3.
Our pervious study has proved that arginine vasopressin (AVP) in periaqueductal gray (PAG) plays a role in antinociception. After establishing a model of local special gene knockdown, the nociceptive effect of vasopressin receptor subunit in PAG was investigated in the rat. Microinjection of short-interfering RNA (siRNA) into PAG, which targeted vasopressin receptor subtypes (V(1a), V(1b) and V(2)), locally weakened the associated mRNA expression and depressed the related receptor synthesis in a dose-dependent manner, in which the significant inhibitive effect occurred on from 7th day to 14th day following 1microg or 2microg siRNA administration. PAG knockdown of V(2) receptor gene markedly decreased pain threshold in from 6th day to 13th day after siRNA administration, whereas local knockdown of either V(1a) or V(1b) receptor gene could not influence pain threshold. The data suggest that V(2) rather than V(1a) and V(1b) receptor in PAG involves in nociception.  相似文献   
4.
老年人血脂水平与载脂蛋白E等位基因的关系   总被引:8,自引:0,他引:8  
为了解老年人血脂水平与载脂蛋白E基因多态性的关系,并探讨载脂蛋白E等位基因对老年人血脂水平的内在影响,利用PCR-RFLP法测定了载脂蛋白E基因型,并用酶学方法对其血脂水平进行了测定。结果发现存在五种不同基因型:与携有ε3等位基因的人群相比,携有ε4等位基因的人群倾向具有较高的总胆固醇和低密度脂蛋白胆固醇水平以及较低的甘油三酯水平,而携有ε2等位基因的人群则有较低的低密度脂蛋白胆固醇水平以及较高的  相似文献   
5.
Zeolite membranes with unique physical and chemical properties are emerging as attractive candidates for membrane separation. However, defects in the zeolite layer seriously affect their molecular sieving performance. In this study, a novel strategy for preparing compact zeolite membranes on rough supports with the assistance of a reticulated hydrotalcite layer was developed. The reticulated hydrotalcite layer was grown on the inner surface of a 170 mm length ceramic tube by an in situ hydrothermal method, and a NaA zeolite membrane was prepared on this reticulated layer by the microwave-heating method. The hydrotalcite interlayer could not only improve the smoothness and regularity of the surface of the support but also fix the Si/Al active ingredients using its reticulate structure, finally effectively improving the quality and stability of the zeolite layer. The optimal molar ratio of the synthesis solution for the synthesis of the zeolite membrane was 3Na2O : 2SiO2 : Al2O3 : 200H2O. The permeance flux of H2 through the zeolite membrane synthesized under the optimal conditions was high as 0.47 × 10−6 mol m−2 s−1 Pa−1, and its permselectivity for H2 over N2 was 4.7, which was higher than the corresponding Knudsen diffusion coefficient. This study provides a new idea for the preparation of defect-free membranes on rough supports.

Reticulated hydrotalcite interlayer controls infiltration of active ingredients into the support, improving the quality and stability of the zeolite membrane.  相似文献   
6.
Sodium-potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) are associated with the transmission of peripheral pain.We investigated whether the increase of NKCC1 and KCC2 is associated with peripheral pain transmission in dorsal root ganglion neurons.To this aim,rats with persistent hyperalgesia were randomly divided into four groups.Rats in the control group received no treatment,and the rat sciatic nerve was only exposed in the sham group.Rats in the chronic constriction injury group were established into chronic constriction injury models by ligating sciatic nerve and rats were given bumetanide,an inhibitor of NKCC1,based on chronic constriction injury modeling in the chronic constriction injury + bumetanide group.In the experiment measuring thermal withdrawal latency,bumetanide (15 mg/kg) was intravenously administered.In the patch clamp experiment,bumetanide (10 μg/μL) and acutely isolated dorsal root ganglion neurons (on day 14) were incubated for 1 hour,or bumetanide (5 μg/μL) was intrathecally injected.The Hargreaves test was conducted to detect changes in thermal hyperalgesia in rats.We found that the thermal withdrawal latency of rats was significantly decreased on days 7,14,and 21 after model establishment.After intravenous injection of bumetanide,the reduction in thermal retraction latency caused by model establishment was significantly inhibited.Immunohistochemistry and western blot assay results revealed that the immune response and protein expression of NKCC1 in dorsal root ganglion neurons of the chronic constriction injury group increased significantly on days 7,14,and 21 after model establishment.No immune response or protein expression of KCC2 was observed in dorsal root ganglion neurons before and after model establishment.The Cl^– (chloride ion) fluorescent probe technique was used to evaluate the change of Cl^– concentration in dorsal root ganglion neurons of chronic constriction injury model rats.We found that the relative optical density of N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (a Cl^– fluorescent probe whose fluorescence Cenintensity decreases as Cl– concentration increases) in the dorsal root ganglion neurons of the chronic constriction injury group was significantly decreased on days 7 and 14 after model establishment.The whole-cell patch clamp technique revealed that the resting potential and action potential frequency of dorsal root ganglion neurons increased,and the threshold and rheobase of action potentials decreased in the chronic constriction injury group on day 14 after model establishment.After bumetanide administration,the above indicators were significantly suppressed.These results confirm that CCI can induce abnormal overexpression of NKCC1,thereby increasing the Cl^– concentration in dorsal root ganglion neurons;this then enhances the excitability of dorsal root ganglion neurons and ultimately promotes hyperalgesia and allodynia.In addition,bumetanide can achieve analgesic effects.All experiments were approved by the Institutional Ethics Review Board at the First Affiliated Hospital,College of Medicine,Shihezi University,China on February 22,2017 (approval No.A2017-169-01).  相似文献   
7.
8.
目的 研究三磷酸腺苷结合盒转运体A1基因启动子区-477C/T单核苷酸多态性与血浆高密度脂蛋白胆固醇和冠心病的关系。方法 用聚合酶链反应限制片长多态性检测124例冠心病患者和111例正常人的三磷酸腺苷结合盒转运体A1基因启动子区-477位点基因型,并比较基因型在冠心痛组与正常人组间、冠心痛组中不同临床表现型之间分布的差异性及三种基因型与冠心痛相关临床指标的关系。结果 TT基因型及T等位基因在冠心病组中的分布频率明显高于正常人组(P〈0.05和P〈0.01)。急性冠状动脉综合征组,TT基因型及T等位基因明显高于稳定型心绞痛组(P〈0.05和P〈0.01)。多支病变组TT基因型明显高于单支病变组(P〈0.05)。在冠心病组中,TT基因型血浆高密度脂蛋白胆固醇水平明显低于CC基因型(P〈0.001)。结论 三磷酸腺苷结合盒转运体A1基因启动子区-477C/T单核苷酸多态性可显著影响中国冠心痛患者血浆高密度脂蛋白胆固醇水平,而且与冠状动脉病变程度及冠心病严重程度相关。  相似文献   
9.
10.
随着细胞与分子遗传学技术在急性白血病(AL)的研究进展中的运用,AL的诊断分型已由1976年提出的以形态学为主的FAB分型发展到2001年的MICM分型,突出体现了细胞和分子遗传学的改变在AL诊断分型的重要地位。除此之外,细胞和分子遗传学改变还对急性白血病的危险度分层、预后判断、治疗指导及新药研发起着重要的指导作用。本文将论述染色体异常和融合基因的表达对急性非淋巴细胞性白血病(ANLL)的诊断分型、预后评估和治疗的指导作用,并对染色体核型正常的ANLL几种常见的基因突变对疾病预后评估做个总结。近年来,对ANLL各型白血病分子细胞遗传学机制的进一步阐释有助于开发新的白血病治疗策略。  相似文献   
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