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1.
关附庚素(GFG)0.86μmol/L使缺O2、高K+和酸中毒的豚鼠乳头肌动作电位零相最大上升速率(Vmax)进一步降低,动作电位时程(APD)和有效不应期(ERP)进一步缩短,而ERP/APD90明显增大。GFG8,16,12μmol/L使兔窦房结动作电位Vmax、舒张期去极化速率(RDD)、自发活动频率(SFF)和平均复极化速率(MRR)显著降低,APD和舒张间隔(DI)明显延长,并呈现浓度依赖性  相似文献   

2.
应用经典玻璃微电极方法对比研究不同浓度奎尼丁(Q)与二氢奎尼丁(DHQ)对豚鼠乳头肌动作电位的影响,随药物浓度递增,两药均使动作电位时程(APD90)逐渐延长,O相最大除极速度(Vmax)逐渐降低,但Q作用的高峰浓度在20μmol/L,而DHQ在10μmol/L,DHQ≤10μmol/L时对Vmax的作用大于Q。提示,DHQ对心肌细胞动作电位的影响大于Q。  相似文献   

3.
用标准玻璃微电极技术观察氨氯地平对豚鼠左房肌快反应动作电位和异丙肾上腺素诱发的早期后除极作用。结果发现氨氯地平5μmol/L对动作电位无影响;10μmol/L可明显缩短动作电位时程(APD),但对动作电位幅度(APA)、0相上升速率(Vmax)、有铲不应期(ERP)和三相时程(DP3)无影响;25μmol/L氨 平可显著抑制异丙蛹地腺素诱发的早期后除极活动。提示:(1)L型钙电流在异丙肾上腺素诱发  相似文献   

4.
通过研究新抗心律失常药甲苯喹哌(toquipidine,Toq)抗心律失常作用的心肌电生理学机制。利用微电极技术观察甲苯喹哌对豚鼠右心室乳头肌动作电位的作用,并与利多卡因进行比较。结果:Toq在1和10μmol/L时对动作电位各参数无明显影响,但在50及100μmol/L时,可明显降低动作电位的Vmax,APA,缩短APD20,APD50和APD90,并明显延长或提高动作电位的ERP,ERP/APD90和ERP-APD90利多卡因1μmol/L对动作电位各参数无明显影响。10和50μmol/L利多卡因可剂量依赖性降低Vmax,APA,缩短APD20,APD50和APD90。并明显延长ERP,ERP/PD90和ERP-APD90结论:Toq有与利多卡因类似的心肌电生理作用,但其效价强度低于利多卡因。  相似文献   

5.
通过研究新抗心律常药甲苯喹哌(toquipidine,Toq)抗心律失常作用的心肌电生理学机制,利用微电极技术观察甲苯喹哌对豚鼠右心室乳头肌动作电位的作用,并与利多卡因进行比较。结果,Toq在1和10μmol/L时对动作电位各参数无明显影响,但在50及100μmol/L时,可明显降低动作电位的Vmax,APA,缩短APD20,APD50和APD90,并明显延长或提高地动作电位的ERP,ERP/AP  相似文献   

6.
雌二醇对兔窦房结起搏细胞动作电位的影响   总被引:2,自引:1,他引:1  
目的: 观察雌二醇(17βestradiol,简称 E)对兔窦房结细胞动作电位的影响。方法:采用常规微电极技术记录兔窦房结细胞在不同 E浓度和作用时间的动作电位。结果:(1) E浓度依赖和时间依赖性显著延长窦房结细胞动作电位时程( A P D50 和 A P D90)及3 期复极时间。(2) E浓度依赖和时间依赖性降低窦房结细胞动作电位0 期最大除极速率( Vm ax)、动作电位幅度( A P A)和延长0 期除极时间,且 E1×105m ol/ L组观察到80~100 m in 时,有3例动作电位完全消失。结论: E对窦房结细胞 K+ 通道和 Ca2+ 通道都有阻断作用。  相似文献   

7.
川芎嗪对豚鼠心室乳头状肌慢反应动作电位的双重作用   总被引:3,自引:0,他引:3  
目的:观察川芎嗪对豚鼠心室乳头状肌慢反应动作电位和收缩力的影响。方法:常规电生理方法,标准玻璃微电极技术。结果:①低浓度川芎嗪(30~30μmol/L)对豚鼠乳头状肌慢反应动作电位的幅度(APA)、时程(APD)、最大去极速度(Vmax)和收缩力(FC)均呈剂量依赖性抑制;②较高浓度的川芎嗪(01~30mmol/L)则可使豚鼠乳头状肌慢反应动作电位的APA、APD、Vmax和FC均呈现剂量依赖性增强;③川芎嗪对豚鼠乳头状肌慢反应动作电位的增强作用可被钙通道阻断剂维拉帕米所拮抗。结论:川芎嗪对心肌慢内向电流具有双重作用,即低浓度抑制,高浓度则增强  相似文献   

8.
采用体外克隆形成培养技术研究维拉帕米(VPL)联用阿霉素(ADM),长春新碱(VCR)和足叶己甙(VP-16)体外净化白血病细胞,结果显示,VPL2.2μmol/L能明显增加单一应用的不同浓度ADM,VCR或VP-16对白血病细胞克隆形成单位(L-CFU)的抑制作用,而不增加其对正常粒巨系克隆形成单位(GM-CFU)的毒性,0.92μmol/LADM,0.0250μmol/LVCR及1.70μmo  相似文献   

9.
pH值对川芎嗪在豚鼠心肌电生理-机械特性的影响中的作用   总被引:1,自引:0,他引:1  
白琴  孔旭黎 《河南医学研究》2000,9(4):298-299,303
目的:观察调节pH至7.4的川芎嗪与不调节pH的川芎嗪对豚鼠心室乳头状肌电生理-机械特性的影响。方法:常规电生理方法,标准玻璃微电极技术。结果:①调节 pH至 7.4与不调节 pH的低浓度川芎嗪(3.0~ 30μmol)均使豚鼠乳头状肌慢反应电位(SAP)的动作电位幅值(APA),动作电位时程(APD),最大除极速度Vmax及收缩力(FC)呈剂量依赖性抑制;②调节pH至7.4的高浓度川芎嗪(0.1~3.0 mmol/L)使豚鼠乳头状肌 SAP的 APA、APD、Vmax及FC呈剂量依赖性增强;而不调节pH的高浓度川芎嗪(0.1~3.0 mmol/L)使豚鼠乳头状肌SAP的APA、APD、Vmax及FC呈抑制效应。结论:①川芎嗪对豚鼠心肌电生理-机械特性有双重影响作用,即低浓度抑制,高浓度增强。②川芎嗪本身的酸性影响川芎嗪对豚鼠心肌电生理-机械特性的正性作用。  相似文献   

10.
两面针碱对钙调蛋白依赖环核苷酸磷酸二酯酶的抑制作用   总被引:1,自引:0,他引:1  
以钙调蛋白依赖环核苷酸磷酸二酯酶(CaM-PDE)为分子模型,应用正文试验证实两面针碱(Ni-tidine,Nit)是一种新的CaM拮抗剂。实验结果表明:①:Nit抑制CaM-PDE活性IC50为86μmol/L。②75μmol/LNit对0~80ng/mlCaM存在下,CaM-PDEVmax基本不变,半激活浓度(AC50)增大,抑制常数(Ki)为66μmol/L。提示Nit以竞争方式拮抗CaM对其靶酶(PDE)的活化。③75μmol/LNit对CaM-PDE抑制动力学研究:改变底物(cAMF)浓度,CaM-PDE的Vmax减少,米氏常数(Km)值增大,Ki为64μmol/L,α>1。提示Nit对CaM-PDE的抑制作用是非竞争一竞争性混合型抑制。由此推测Nit可能通过与CaM竞争酶分子上的CaM结合位点从而抑制CaM-PDE的激活活性。  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   

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