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1.
陈鸣  府伟灵  蔡国儒  俞丽丽  刘明华  张波  蒋天伦  陈庆海  吴蓉 《重庆医学》2004,33(10):1528-1529,1531
目的探索肽核酸生物传感器检测系统构建时靶序列浓度值对杂交效应的影响,以及靶序列浓度线性范围的确定.方法石英谐振式生物传感器阵列表面先固定上1.5μM的bis-PNA探针,观察终浓度为1pg/L至100μg/L的HBV DNA与探针进行杂交所引起的频率变化及反应所需时间.并对频率下降值与靶序列浓度做线性回归,确定其线性范围.结果靶序列浓度为1 pg/L时,传感器未能检测出任何频率的改变.随着浓度从10 pg/L增加到100μg/L,杂交反应引起的频率下降值呈先增加后趋于缓和的趋势,以10μg/L为分界线,而杂交平衡时间并没有显现出一定的变化趋势.在10pg/L到10μg/L的浓度范围内,浓度与频率下降值的线性回归方程为lgC=-2.745 5 0.069 1×△F,相关系数r=0.992 3.结论随着靶序列浓度的升高,杂交反应引起的频率下降值呈典型饱和曲线趋势,靶序列浓度的线性检测范围为:10 pg/L ~ 10μg/L.  相似文献   

2.
目的 探讨乙型脑炎病毒(Japanese encephalitis vires,JEV)靶序列浓度值对漏声表面波(LSAW)基因传感器检测系统的影响.方法 LSAW基因传感器表面固定终浓度为0.5 μmol/L的JEV探针,然后用pH 7.6的10 mmol/L PBS缓冲液(含Na+ 0.3 mol/L)中和终浓度为0.05、0.1、0.5、1.0、1.5、2.0 μmoL/L的JEV靶序列杂交,分别记录相位变化及反应所需时间.结果 与JEV探针反应引起的相位变化是先缓慢上升后趋于缓和的趋势,以1.0 μmol/L靶序列浓度为分界线;杂交平衡时间上除0.05 μmol/L的时间短以外,其他的未见明显变化趋势,当靶序列浓度为1.0 μmol/L,杂交反应平衡时间为33 min.结论 随着靶序列浓度的升高,杂交反应引起的相位变化呈典型的饱和曲线趋势;靶序列浓度为1.0 μmol/L、杂交反应的平衡时间为33 min,是LSAW基因传感器杂交的最适反应条件.  相似文献   

3.
缓冲液离子浓度对新型PNA-LSAW基因传感器杂交效应的影响   总被引:1,自引:0,他引:1  
陈鸣  陈伟  府伟灵  张烨  王云霞  徐清华  丁毅  曹亮 《重庆医学》2008,37(17):1939-1940
目的 探讨PBS缓冲液的离子浓度对构建的肽核酸(PNA)漏声表面波(LSAw)基因传感器杂交效应的影响.方法 将1.0μmol/L的PNA探针固定在LSAW基因传感器表面,分别加入10、20、50、100mmol/L的PBS缓冲液,观察不同离子浓度的PBS缓冲液对PNA-LSAW基因传感器杂交效应的影响,记录分析传感器相位的变化值及反应所需的时间.结果 当钠离子浓度从10mmol/L增加至100mmol/L时,传感器的相位变化呈先升高后降低的趋势,以20mmol/L为分水岭.而杂交平衡时间增加显著.结论 离子浓度极大地影响了杂交反应的时间,低盐离子浓度更有利于提高PNA和靶序列的杂交速率,高盐离子浓度则会大大降低PNA的结合速率.离子浓度为20mmol/L时杂交最为适宜.  相似文献   

4.
【目的】研制1个以亚甲基兰(MB)为电化学活性物质的电化学DNA生物传感器。【方法】寡聚DNA探针通过-SH与Au的反应而连到金电极表面,用线性扫描伏安法检测电极表面DNA是否组装完成;用与探针DNA完全互补的ssDNA溶液与探针进行杂交反应。【结果】与目标DNA杂交后,dsDNA电极较ssDNA探针电极的峰电流显著增加,当目标DNA的浓度在5.0×10-10到1.8×10-9mol/L时,MB的峰电流与目标DNA浓度呈线性关系,检出限是5.0×10-10mol/L。【结论】用亚甲基兰(MB)作为电化学活性指示剂,具有高度的灵敏性,可成功对特定DNA片断进行选择性的识别和测定。  相似文献   

5.
目的分子信标探针在芯片表面的固定结合是限制其在芯片技术领域运用的难题。本研究拟寻找一种将分子信标探针固定在芯片表面的新方法,同时对其中重要影响因素进行优化探讨。方法本实验设计一种带单侧延长臂分子信标探针,固定在芯片表面进行杂交、扫描等后续实验。提高杂交效率部分优化包括:分子信标探针浓度;杂交温度、杂交时间;杂交液配方;4种分子对分子信标荧光信号比较。结果较理想区分阴阳性信号强度理想的探针浓度:Cy3-BDH分子信标探针浓度约10μmol/L,FAM-DABCLYE约15μmol/L。讨论单侧延长臂分子信标特异性高、敏感性高、技术难度低,对中、高密度芯片杂交可做到“点对点杂交”。  相似文献   

6.
目的 探讨探针浓度对压电传感器基因杂交效应的影响。方法 9种浓度的探针与同一浓度的靶序列在压电传感器阵列上进行杂交,计算机采集并分析传感器频率数据,比较各探针浓度下固定前后频率差,杂交达到平衡所需时间,杂交前后频率差,同时,根据较低浓度数据得出的杂交动力学参数。计算各浓度下的频率变化理论值。结果 随探针浓度增加,固定引起的频率变化值逐渐增加,杂交时间有缩短趋势,杂交前后的频率差值在探针浓度较低(1nmol/L-0.5μmol/L)时逐渐增大,而探;针浓度较高(1.0-3.5μmol/L)时反而减小,高浓度时杂交前后频率变化理论值与实际值存在明显差异。结论 在石英晶体传感器阵列上,基因杂交效率随探针浓度增加而增大,但探针浓度过高反而抑制杂交,其原因可能主要在于探针之间的空间构象关系和静电排斥。  相似文献   

7.
闫慧慧  府伟灵  张波  赵渝徽 《重庆医学》2007,36(20):2077-2078,2081
目的 探讨不同探针浓度对蛋白质-DNA相互作用新型压电生物传感器结合效应的影响.方法 将6种不同浓度NF-κB顺式作用元件(DNA)探针通过巯基化法固定在传感器的金膜表面,并与特异性蛋白NF-κB 的p65亚基进行结合反应,通过计算机采集分析传感器频率数据,观察不同浓度探针与p65亚基结合反应所引起的频率变化及反应所需的时间.结果 在DNA顺式作用元件探针浓度为0.25~3.0μmol/L的范围内,随着探针浓度的增加,p65蛋白与DNA探针结合反应所引起的传感器频率变化逐渐增加,当探针浓度为2.0μmol/L时所引起的频率变化与探针浓度为3.0μmol/L所引起的频率变化差异无统计学意义(P>0.05);同时p65蛋白与DNA的结合反应平衡时间随着探针浓度的增加有缩短趋势,当探针浓度为2.0μmol/L时,结合反应平衡时间最短为15min.结论 随着DNA探针浓度的增加,蛋白质-DNA结合反应引起的频率下降呈典型的饱和曲线趋势,探针浓度为2.0μmol/L、反应时间为15min,是蛋白质-DNA相互作用压电生物传感器的最适结合反应条件.  相似文献   

8.
目的:建立一种高效显色反应,考察以四核环金属化钯-偶氮配合物(MOP)为探针分子,定性跟踪识别青霉素在不同条件下的代谢产物。方法:探针分子MOP浓度为2.0×10-5mol/L,在pH=7.4的磷酸盐缓冲溶液条件下,与初始浓度为4.0×10-4mol/L样品溶液在不同代谢条件下室温反应30min后进行检测。结果:探针分子能够实现对青霉素不同代谢条件下代谢产物的选择性识别,并给出识别机理。结论:本方法探针分子容易制备,样品处理简单,分析速度快,重现性好,可以实现青霉素降解产物的定性识别。  相似文献   

9.
目的 确定Taqman探针等位基因鉴别技术检测VEGF基因C-634G多态性的最适实验条件.方法 对影响VEGF基因C-634G多态性Taqman探针检测的反应体系及探针、引物浓度等主要因素进行了系统研究.结果 最适反应体系为12.5μL,最适探针、引物浓度为:0.3/12.5μL.结论 建立了Taqman探针检测VEGF基因多态性的稳定实验方法 .  相似文献   

10.
随机引物引导的探针标记足一种比切中移位更为有效的探针标记方法,作者应用这种方法制备~(32)P标记的乙型肝炎病毒(HBV)DNA探针。经液闪测定,探什比放射性为lxl0~(9)cpm/ug,(32)P掺入率为71.43%,均比切口移位有关参数上限高出数倍。将这种探针用于尼龙膜载样杂交,在每100cm~(2)的样膜所加探针放射性强度为5 x10~(6)cpm、浓度为20ug/L条件下,放射自显影24小时即可出示清晰结果。并且检出HBV DNA灵敏度达0.1Pg,检测HBSAg和HBCAg双阳性血清,HBVDNA阳性率达87%(26/30)。用这种方法还制备地高辛素标记的HBV DNA探针,并在探针浓度为20 ug/L条件下,对~(32)p探针杂交过的样膜重复杂交。结束检出HBV DNA灵敏度为0.05 Pg,检测HBsAg和HBeAg双阳性血清,HBV DNA阳性率为73%(22/30)。上述结果表明随机引物引导标记可用于制备高比放同位素探针和高敏感性非同位索探针。前者对研究微量基因必不可少,后者对基层单位常规开展检测非常重要。  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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