首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
目的:观察不同剂量右美托咪定(dexmedetomidine,DEX)预处理对大鼠局灶性脑缺血再灌注损伤的影响。方法:50只健康雄性SD大鼠,随机分为假手术组(Sham组)、缺血再灌注组(I/R组)、小剂量右美托咪定组(D1组)、中等剂量右美托咪定组(D2组)、较大剂量右美托咪定组(D3组)。Sham组仅行外科操作而不造成缺血,Sham组、I/R组于外科操作前30 min腹腔注射生理盐水1 mL,D1、D2、D3组分别于缺血操作前30 min腹腔注射DEX 50、100、200 μg/kg。各组分别于术后24、48 h检测S100β蛋白含量,术后48 h测定Bcl?2、Bax含量及脑梗死体积比。结果:与Sham组相比,D1、D2、D3组S100β、Bax蛋白含量及脑梗死体积比均升高(P<0.05),Bcl?2含量降低(P<0.05);与I/R组相比,D1、D2、D3组S100β、Bax蛋白含量及脑梗死体积比均降低(P<0.05),Bcl?2含量升高(P<0.05);D1、D2、D3组间相比,D3组Bcl?2含量较D1、D2组降低(P<0.05),术后24 h S100β蛋白含量较D1、D2组升高(P<0.05),D1、D2组间差异无统计学意义;D1、D2、D3组间术后48 h S100β、Bax蛋白含量及脑梗死体积比差异无统计学意义。结论:右美托咪定预处理对局灶性脑缺血再灌注损伤大鼠有神经保护作用,其机制可能与抑制细胞凋亡有关,此作用在50和100 μg/kg间无明显差异。  相似文献   

2.
目的 探讨右美托咪定(DEX)对小鼠脑缺血/再灌注(I/R)损伤的影响及线粒体融合与裂变在其中的作用。方法 将雄性ICR小鼠随机分为假手术(sham)组、缺血/再灌注(I/R)组、缺血/再灌注+右美托咪定(I/R+DEX)组、缺血/再灌注+右美托咪定+dorsomorphin(I/R+DEX+dorsomorphin)组。采用改良线栓法制备小鼠大脑中动脉栓塞模型,于缺血前30 min 腹腔注射DEX50 μg/kg,缺血1 h,再灌注24 h;采用Longa五分法对小鼠进行神经行为学评分;TTC染色法检测小鼠脑梗死体积,并计算脑梗死体积百分率;透射电镜法观察线粒体形态变化;免疫印迹法检测磷酸化AMP蛋白激酶、线粒体融合蛋白2、线粒体裂变相关蛋白的表达变化。结果 DEX 预处理降低了 I/R 组小鼠神经行为学评分和脑梗死体积百分率,在使用 DEX 的基础上加用dorsomorphin后,小鼠神经行为学评分和脑梗死体积百分率升高(P<0.01);电镜结果显示,DEX减轻了缺血再灌注导致的线粒体损伤(P<0.01),线粒体形态有所恢复。免疫印迹检测结果显示,DEX预处理增加了磷酸化AMP蛋白激酶、线粒体融合蛋白2表达,降低了线粒体裂变相关蛋白表达,而加用dorsomorphin后,磷酸化AMP蛋白激酶、线粒体融合蛋白2表达明显降低,线粒体裂变相关蛋白表达显著增加(P<0.01)。结论 DEX预处理可以减轻I/R损伤,其机制可能与激活AMPK从而促进线粒体融合 及抑制线粒体裂变有关。  相似文献   

3.
目的:评价右美托咪啶后处理对大鼠离体心肌缺血再灌注损伤后心功能及梗死面积比的影响。方法30只健康雄性SD大鼠,体重200~240 g,将其随机分成5组( n=6):持续灌注组( C组)、缺血再灌注组( I/R组)、2.4μg/L右美托咪啶后处理组( D组)、育亨宾组( Y组)、育亨宾+2.4μg/L Dex后处理组( Y+D组)。制备离体心脏Langendorff灌注模型,各组经主动脉灌注K-H液,除C组持续灌注140 min外,其余各组均平衡灌注20 min后停灌30 min,再灌注90 min。记录平衡末、再灌注15、30及90 min时的左心室舒张末压( LVEDP)、左心室发展压(LVDP)、左心室压力上升(或)下降最大速率(&#177;dp/dtmax)及心率(HR)。再灌注90 min时采用2,3,5-氯三苯四唑( TTC)染色法染心肌片并计算心肌梗死面积百分比。结果与I/R组比较,D组心率在再灌注15 min及再灌注30 min下降(P<0.05),再灌注末恢复(P>0.05);心肌梗死面积比增加(P<0.05〕。与D组比较, Y+D组心率在再灌注15 min及再灌注30 min上升;心肌梗死面积比减少( P<0.05〕。结论右美托咪啶后处理使大鼠离体心肌的心率下降,心肌梗死面积比增加,其机制与激动α2-肾上腺素受体有关。  相似文献   

4.
目的:探讨大鼠脑缺血再灌注时右美托咪定对JAK1/STAT1信号通路的影响。方法:选取体重220~260g,SD大鼠40只,随机分为5组(n=8):假手术组(C组)、脑缺血再灌注组(I/R组)、右美托咪定25μg/kg组(D1组)、右美托咪定50μg/kg组(D2组)、右美托咪定75μg/kg组(D3组),实验开始时,C组仅进行外科操作暴露颈外动脉而不造成脑缺血,I/R组进行脑缺血操作30min前腹腔内注射无菌生理盐水1ml,D1组、D2组、D3组分别于脑缺血操作30min前腹腔内注射右美托咪定25μg/kg、50μg/kg、75μg/kg(均稀释至1ml)。缺血120min后,将I/R组、D1组、D2组、D3组预留的尼龙线线栓退出,恢复大脑中动脉血供,实现再灌注。术后24h后,每组选取2只大鼠取脑组织采用Western Blot方法检测其p-JAK1、p-STAT1表达水平。结果:脑缺血再灌注时,脑皮质缺血半暗带区p-JAK1、p-STAT1的表达均增高,在右美托咪定治疗组中p-JAK1、p-STAT1的表达均有所减低,其中右美托咪定50μg/kg组降低最为明显。结论:右美托咪定对大鼠脑缺血再灌注损伤时保护作用与其下调JAK1/STAT1信号转导通路有关,其中右美托咪定50μg/kg组更为明显。  相似文献   

5.
目的::探讨环黄芪醇对大鼠局灶性脑缺血再灌注损伤脑组织的保护作用。方法:采用线栓法建立大鼠局灶性脑缺血再灌注(缺血2h再灌注24h)模型并给予环黄芪醇干预,评价大鼠的Garcia JH神经功能评分,并采用TTC染色法计算大鼠的脑梗死灶容积百分比。结果:环黄芪醇中、高剂量组大鼠神经功能评分明显高于模型组(P<0.05),脑梗死灶容积百分比明显低于模型组(P<0.05)。结论:环黄芪醇能提高脑缺血再灌注损伤大鼠的神经功能评分、缩小脑梗死体积,对局灶性脑缺血再灌注脑组织损伤具有保护作用。  相似文献   

6.
目的观察右美托咪定预处理对大鼠缺血再灌注心律失常的影响及机制。方法 2015年3-6月于武汉大学基础医学院选择30只雄性SD大鼠,随机分为假手术组(SO组)、缺血再灌注组(I/R组)、右美托咪定预处理组(DEX组)各10只。I/R组、DEX大鼠先结扎冠状动脉30 min引起心肌缺血,再松开结扎线给予心肌再灌注120min。SO组只带线不结扎,DEX组在缺血前2 h给予右美托咪定100μg/kg腹腔注射,I/R组给予等体积生理盐水。监测记录各组缺血再灌注心律失常的发生情况,以实时定量PCR法检测心肌组织L型钙通道(Cav1.2)、钠钙交换体(NCX)mRNA的水平。结果 SO组心律无明显变化,心律失常评分为0分。DEX组心律失常发生率低于I/R组,缺血30 min和再灌注120 min心律失常评分均低于I/R组(4.5±0.6 vs.2.1±0.4,3.7±0.5 vs.1.1±0.3,P均<0.05)。与SO组比较,I/R组、DEX组心肌组织Cav1.2和NCX的mRNA水平均升高,而DEX组较I/R组明显降低(P均<0.05)。结论右美托咪定预处理可减少缺血再灌注心律失常发生,与减少Cav1.2和NCX的mRNA水平,抑制钙超载有关。  相似文献   

7.
目的探究右美托咪啶(dexmedetomidine,DEX)预处理对大鼠肾缺血再灌注损伤后。肾及肝抗氧化能力的影响。方法90只雄性SD大鼠随机分为3组(n=30),右美托咪啶预处理组(DEX组),缺血再灌注组(IRI组),假手术组(Sham组)。DEX组于建模前30min腹腔注射DEX(100μg/ks),其余两组腹腔注射等量0.9%氯化钠注射液,建立肾缺血再灌注模型,再灌注后2h、8h、24h肝肾组织匀浆检测超氧化物歧化酶(serum levels of superoxide dismutase,SOD)、一氧化氮(nitric oxide,NO)、乳酸(lactate dehydrogenases,LD)、还原型谷胱甘肽(reduced glutathione,GSH)及总抗氧化能力(total antioxidant capacity,T—AOC)。结果与IRI组相比,DEX组肾匀浆SOD升高,总NO降低,T—AOC升高(P〈0.05),LD再灌注8h后降低明显(P〈0.05);肝SOD升高,总NO升高,T—AOC升高(P〈0.05),LD再灌注8h、24h降低显著(P〈0.05)。结论右美托咪啶预处理可提高大鼠肾缺血再灌注后肾及肝的抗氧化能力,减少乳酸堆积。  相似文献   

8.
目的应用超声造影定量分析技术评价右美托咪定(DEX)对兔肾缺血/再灌注(I/R)损伤时微循环灌注的影响。方法新西 兰家兔24 只随机分成3 组(每组8 只):对照组、肾缺血/再灌注损伤组(I/R组)和右美托咪定组(DEX组)。I/R 组和DEX 组切 除右肾建立左肾缺血再灌注损伤模型。DEX 组在肾缺血前30 min 腹腔注射10 μg/kg 右美托咪定。再灌注24 h 后,测定肾脏 大小和肾血流阻力(RI),超声造影观察肾皮质灌注,时间-强度曲线定量分析达峰时间(TTP)、峰值强度(PSI)、曲线上升斜率 (Grad)和曲线下面积(AUC)。取肾脏观察病理改变。结果与对照组比较,I/R 组和DEX 组肾大小和病理改变明显,RI 增高, TTP 延长,PSI 和Grad 降低,AUC 显著增加(P<0.05);与I/R 组比较,DEX 组肾大小和病理改变明显改善,RI 降低,TTP 缩短, PSI 和Grad 增高,AUC 减少(P<0.05)。结论超声造影结合时间-强度曲线参数能动态定量分析右美托咪定改善兔肾缺血/再灌 注损伤时的微循环灌注。  相似文献   

9.
《中国现代医生》2020,58(35):39-42
目的 观察右美托咪定对脑缺血再灌注损伤大鼠大脑皮质Wnt/β-catenin 蛋白表达的影响。方法 将48 只雄性SD 大鼠按随机区组的原则分为三组:对照组、模型组和右美托咪定组,每组各16 只。采用大脑中动脉阻塞(Middle cerebral artery occlusion,MCAO)法制造大鼠脑缺血再灌注损伤模型。右美托咪定组于缺血1 h 即刻经尾静脉注射1 μg/kg 右美托咪定作为负荷剂量,持续10 min,随后以0.5 μg/(kg·h)的速率静脉输注至脑缺血2 h。对照组和模型组大鼠按相同方法给予生理盐水。再灌注24 h 时进行神经功能评分后处死大鼠取出脑组织,各组取8 只大鼠脑组织行TTC 染色法测定脑梗死体积,另8 只大鼠采用Western blot 法检测大脑皮质β-catenin 蛋白表达量。结果 与对照组相比,模型组大鼠神经行为学评分明显增加[(3.00±0.82) vs (0±0),P<0.05]、脑梗死体积明显增加[(64.23±6.72)% vs (0±0)%,P<0.05],β-catenin 蛋白表达量明显减少(0.46±0.14 vs 1.12±0.23,P<0.05)。与模型组相比,右美托咪定组大鼠神经行为学评分(1.69±0.71 vs 3.00±0.82,P<0.05)、脑梗死体积明显减少[(45.13±8.29)% vs (64.23±6.72)%,P<0.05],β-catenin 蛋白表达量明显增加[(0.82±0.23) vs (0.46±0.14),P<0.05]。结论 右美托咪定能减轻大鼠脑缺血再灌注损伤,其机制可能与增加大脑皮质中β-catenin 蛋白表达量有关。  相似文献   

10.
目的探讨右美托咪啶预处理对抑制NF-κB活化及减轻肢体缺血再灌注损伤的影响及机制。方法将21只成年雄性SD大鼠按随机数字表法分为假手术组(Sham组)、缺血再灌注组(I/R组)、缺血再灌注+右美托咪啶预处理组(DEX组),每组各7只。DEX组在麻醉后腹腔注射右美托咪啶25滋g/kg,其余两组给予相应体积的0.9%氯化钠溶液,30min后单侧股部切口,无创动脉夹夹闭股动脉,用橡皮筋以恒定张力结扎该侧肢体,Sham组仅行股部手术、分离股动脉不夹闭,其余两组缺血3h后去除动脉夹及橡皮筋。采用ELISA法检测血清IL-1、IL-6、TNF-α,Westernblot检测胞核NF-κB,光镜观察腓肠肌形态,并测定湿/干重比值。结果显微镜下可见Sham组大鼠腓肠肌肌纤维排列整齐、间质少有炎性细胞浸润,I/R组大鼠腓肠肌肌纤维排列紊乱并出现明显水肿、间质中出现大量炎症细胞,DEX组大鼠腓肠肌肌纤维排列欠规则、间质中有少量炎性细胞,但较I/R组有所好转。与Sham组相比,I/R组湿/干重比值、IL-1、IL-6、TNF-α、NF-κB水平均明显升高(均P<0.05);与I/R组相比,DEX组湿/干重比值、IL-1、IL-6、TNF-α、NF-κB水平均明显降低(均P<0.05)。结论右美托咪啶可抑制NF-κB信号通路活化,减轻肢体缺血再灌注损伤。  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

19.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

20.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号