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1.
目的为了证实电压钳技术测得的电流变化能说明诱导的昆虫离体细胞Tn-5B1产生的抗菌活性肽类物质的抗菌机制。方法将制备的抗菌肽作用于去掉滤泡膜的爪蟾卵母细胞,利用电压钳技术记录的电流研究抗菌肽抗菌机制。结果去掉滤泡膜的非洲爪蟾卵母细胞可作为模式细胞研究离子通道,抗菌肽作用于爪蟾卵母细胞14 min后,检测到了电流的变化,而且表现为外向电流持续升高。结论细胞经抗菌肽作用后产生了离子通道,此离子通道使得阳离子外流,初步证实该抗菌肽通过破坏坏细菌细胞来达到杀菌目的 。  相似文献   

2.
目的 记录和区分卵母细胞内源性P2型嘌呤受体及表达的外源性P2型嘌呤受体介导的膜电流。方法 应用双电极电压钳技术分别在带滤泡膜及去滤泡膜后注入RNA并经孵育的卵母细胞记录膜电流。结果 根据所用卵母细胞标本的制备(是否去滤泡膜及是否注入RNA并孵育)以及电流的形式及幅值,可将内源性P2型嘌呤受体和表达的外源性P2型嘌呤受体介导的膜电流区分开来。结论 应用以上方法可区分两种不同的三磷酸腺苷(adenosine triphosphate,ATP)激活电流。  相似文献   

3.
NMDA受体亚基NR1的体外表达及功能检测   总被引:1,自引:0,他引:1  
目的:体外表达NMDA受体亚基NR1并了解其电生理学特性,探讨体外表达受体亚基的意义。方法:将克隆的NMDA受体亚基NR1质粒DNA经体外转录成RNA,显微注射到爪蟾卵母细胞后进行受体表达,采用双电极电压钳位技术记录表达的NR1亚基的激活电流。结果:注射NR1亚基RNA的爪蟾卵母细胞能表达出具有电生理学功能的受体,其激活电流能被D-AP5阻断等特性,说明该表达的NR1亚基具有NMDA受体的功能。结  相似文献   

4.
目的:验证Nielsen假设的正确性。方法:体外转录辣椒素受体(VRI)cDNA,获得CRmRNA,注入非洲爪蟾卵母细胞,异源性表达VRI。用甲醛刺激异源性表达的VRI。用双电极电压钳记录。结果:实验组有3个细胞对激动剂辣椒素(capsaicin 10^-7mol/L)有反应,并且VRI拮抗剂(capsazepine 10^-5mol/L)能完全阻断此内向电流。结论:表达的VRI对甲醛刺激发生反应。验证了Nielsen假设的正确性。  相似文献   

5.
目的:探讨大鼠心室肌细胞肿胀激活氯电流ICl,swell在等渗(1T)及低渗(0.6T)溶液中的变化。方法:①采用图文采集及分析系统测量并比较大鼠心室肌细胞在等渗(1T)及低渗(0.6T)溶液中体积的变化。②采用全细胞电压钳方式记录大鼠心室肌细胞在1T及0.6T溶液中ICl,swell的变化。结果:①大鼠心室肌细胞在0.6T溶液中比1T中体积增大37.4%。②心室肌细胞在1T溶液中未见电流激活,在0.6T溶液中可见到内向及外向电流增大,其外向电流可被1mmoL/L9AC抑制。结论:大鼠心室肌细胞低渗性肿胀可激活ICl,swell,且能被9AC抑制,后者可能在充血性心力衰竭心律失常的发生起重要作用。  相似文献   

6.
脑片技术和膜片钳技术的结合是目前离体神经系统神经元网络研究的前沿技术。作者对其中的盲法和离子孔道法进行了改进,用解剖显微镜代替倒置显微镜,对记录电极的拉制进行改良,使之不必进行抛光处理,在离子孔道记录时,去极化电压钳位可稳定记录达0~40mV。作者并于实验中筛选出典型的电反应波形以便于判断获得良好的电极膜封闭。上述改进降低了仪器费用,同时也利于获得稳定的记录,因而使此技术更易于推广应用。  相似文献   

7.
脑片膜片钳法———改进的盲法和离子孔道法   总被引:2,自引:0,他引:2  
脑片技术和脑片钳技术的结合是目前离体神经系统神经元网络研究的前沿技术。作者对其中的盲法和离子孔道法进行了改进,用剖解是微镜代替倒置显微镜,对记录电极的拉制进行改良,使之不必进行抛光处理,在离子孔道记录时,去极化电压钳位可稳定记录达0.40mV。作者并于实验中筛选出典型的电反应波形便于判断获得良好的电极膜封闭。上述改进降低了仪器费用,同时也利用获得稳定的记录,因而使此技术更易于推广应用。  相似文献   

8.
把提取的鼠脑mRNA注射到卵母细胞内,在卵母细胞上以双电极电压钳技术研究某些递质的诱导电流,实验发现除卵母细胞本身所具有的muscarine受体外,还有多种受体明显地在卵母细胞上表达,卵母细胞膜上的表达受体的反应可分平滑型,振荡型,复合型三类,其反应类型与所开启的通道及通透离子有关,平滑型反应的受体与离了通道为一复合体,激动剂开启其自身离子通道,而振汇型反应是递质通过第二信使的介导,引起胞内Ca^2 库中Ca^2 释放,开启卵母细胞膜本身的Cl^-通道,产生Ca^2 依赖的Cl^-电流,构成振荡型电流反应的主要成分,复合型二者兼有。  相似文献   

9.
目的 :研究牛蛙球囊毛细胞膜上钾通道的类型。方法 :全细胞膜片钳技术。结果 :1当钳制电位为 - 1 0 0 m V,以 1 0 m V的步距阶跃 ,阶跃从 - 70 m V至 + 2 0 m V,随着膜电位的去极化 ,可记录到一系列快速、瞬时的外向电流 ,4- Ap对其有特异性阻断作用。激活电压为 - 53.85± 7.8m V。2 A型钾通道的数量在牛蛙毛细胞间存在差异。 3当钳制电位为 - 70 m V,以 1 0 m V的步距阶跃去极化 ( - 50 m V~ + 4 0 m V) ,可产生一延迟整流性钾离子流 ,四乙基氯化氨 ( TEA)能使该电流幅度下降 59%± 1 1 %。结论 :牛蛙毛细胞膜上含有 A型钾通道和延迟整流性钾通道。  相似文献   

10.
<正> 在离体新生大鼠脊髓切片对218个经逆行激活鉴定的运动神经元(MN)进行电流或电位记录,发现灌流(10~100μmol/L)或压力注射5-羟色胺(5-HT),使81%的 MN 发生去极化或内向电流,9%发生超极化或外向电流,在57%的 MN 诱发了包含 EPSP 和(或) IPSP 的突触活动。5-HT 诱发的突触活动不仅可被低  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 investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.  相似文献   

18.
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   

19.
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   

20.
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   

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