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.
应用噬菌体肽库筛选Endoglin的结合肽   总被引:2,自引:1,他引:2  
目的 利用噬菌体12肽库筛选可与Endoglin结合的活性小分子肽.方法 以rhEndoglin为靶分子,对噬菌体12肽库进行亲和筛选.经过3轮筛选,随机挑取16个克隆,双夹心ELISA法鉴定其亲和性,测定亲和力高的阳性噬菌体克隆的DNA序列,推断出与噬菌体外壳蛋白融合的氨基酸序列,竞争抑制实验检测优势克隆的特异性.结果 竞争性ELISA显示6个噬菌体克隆与rhEndoglin有较强的结合活性,经测序获得5种不同的多肽序列,其中2个克隆的氨基酸序列为:AHKHVHHVPVRL.结论 噬菌体随机肽库技术可以获得Endoglin结合肽的蛋白质序列.  相似文献   

2.
脂多糖结合蛋白与CD14结合位点模拟肽的初步筛选   总被引:3,自引:3,他引:3  
目的 应用噬菌体随机12肽库筛选脂多糖结合蛋白(lipopolysaccharide binding protein,LBP)与CD14结合位点的多肽序列.方法 以CD14为固相筛选分子,对噬菌体12肽库进行4轮亲合筛选,采用酶联免疫吸附(ELISA)法鉴定筛选后的噬菌体克隆与CD14的结合活性,取结合活性较高的克隆进行DNA测序,推导其多肽序列并与LBP序列比对,再进行竞争抑制实验检测筛选噬菌体与LBP竞争结合CD14的效力.结果 挑取的20个噬菌体克隆中,16个结合实验鉴定阳性,取6个亲和力最高的克隆测序,得到3条不同编码的12肽序列(FHRWPTWPLPSP、MHRHPPPITLPL和AAFHRAHHLTSP),3条多肽与LBP一级结构同源性低,为模拟肽.6个噬菌体克隆有较高的竞争抑制率.结论 用噬菌体12肽库成功筛选出LBP与CD14结合位点的模拟肽.  相似文献   

3.
丁宁  佘守章  姜勇 《广东医学》2008,29(1):55-57
目的 应用噬菌体展示随机肽库技术,进行肿瘤坏死因子-α(TNF-α)高亲和肽的筛选研究.方法 以重组人TNF-α为靶标分子,对噬菌体展示环七肽库进行3轮亲合筛选,ELISA结合实验鉴定阳性克隆,对获得的阳性克隆进行DNA序列测定,推导短肽的氨基酸残基序列.结果 3轮筛选后,随机挑取的15个噬菌体克隆中7个可与TNF-α结合.测序发现这7个阳性克隆融合多肽中的序列完全一致,均为STPTRYS.结论 筛选到一个可与TNF-α高亲力结合的噬菌体多肽,该肽序列能否阻断TNF-α的活性有待进一步阐明.  相似文献   

4.
目的筛选获得高表达人CD59中国仓鼠卵巢细胞(CHO)表面与人CD59特异性结合的短肽序列,为下一步研究与肿瘤逃逸相关的CD59活性位点的短肽药物提供实验依据。方法以离子层析柱纯化的CHO细胞的裂解蛋白纯蛋白为靶分子分别进行5轮亲和筛选,并进行竞争结合实验,双夹心ELISA方法鉴定噬菌体阳性克隆。提取阳性单克隆单链DNA测序,并推导出短肽序列。结果随机挑选的16个单克隆中有10个克隆对CHO细胞纯蛋白有特异性结合力,经测序得到两条高度同源的多肽序列。结论通过噬菌体随机肽库对CHO细胞进行纯蛋白筛选得到了能与人CD59特异性结合的短肽序列。  相似文献   

5.
利用噬菌体肽库筛选可结合TNF—α的短肽序列   总被引:5,自引:1,他引:4  
目的 对噬菌体环七肽库进行筛选。寻求可拮抗肿瘤坏死因子a(TNF-α)活性的小分子短肽。方法 以rhTNF-α为靶筛选噬菌体环七肽库,双夹心ELISA鉴定阳性克隆。结果 ELISA鉴定随机挑选经3轮筛选后所得23个噬菌体克隆发现,其中11个克隆显示与TNF-α有较强的结合,DNA测序发现其中两个克隆的氨基酸序列为:c-ALWHWWH-c,另9个克隆序列为:c-(T/S)WLHWWA-c。结论 噬菌体克隆展示肽能够模拟TNF-α受体或抗体的结合表位,为TNFα结合肽。  相似文献   

6.
目的 通过噬菌体展示肽库技术筛选VPAC1高亲和力结合十二肽配体,并进行特异性和亲和力鉴定.方法 建立稳定表达VPAC1的真核细胞系;利用噬菌体肽库展示技术进行全细胞差减筛选,随机挑取40个噬菌体克隆进行测序,初步鉴定确定阳性克隆,明确外源十二肽序列,固相合成该十二肽;利用体外竞争结合ELISA及流式细胞分析,鉴定目标多肽与VPAC1受体结合的特异性及亲和力.结果 成功构建稳定表达VPAC1细胞系;经过4轮差减筛选,回收噬菌体逐轮得到富集,随机挑取40个克隆测序,共得到15条序列不同的多肽,经ELISA鉴定有7个克隆与细胞有特异性高结合能力;阳性噬菌体克隆与细胞结合通过多肽VP1介导;VP1能特异高亲和地与VPACl受体结合.结论 通过噬菌体展示肽库技术成功筛选得到与VPAC1高亲和力特异结合十二肽.  相似文献   

7.
目的:对噬菌体随机12肽库进行筛选,寻求可与Endoglin结合的小分子短肽并测定其亲和常数.方法:经过3轮"吸附-洗脱-扩增"后,随机挑取16个克隆,双夹心ELISA法鉴定其亲和性,测定阳性克隆的DNA序列,竞争抑制实验检测优势克隆的特异性,非竞争法ELISA固相法计算阳性噬菌体融合肽的亲和常数.结果:三轮生物筛选,噬菌体得到有效富集,竞争性ELISA显示6个阳性噬菌体克隆与rhEndoglin有较强的结合活性,测序获得5种多肽序列,优势序列为:AHKHVHHVPVRL,竞争抑制实验显示阳性噬菌体克隆与Endoglin有良好的亲和性,其亲和常数为:(1.431±0.293)×107 mol/L.结论:利用噬菌体肽库技术可以获得亲和力较强的Endoglin的结合肽,为今后进一步研究Endoglin在卵巢癌的早期诊断方面的作用奠定基础.  相似文献   

8.
目的从噬菌体12肽库中筛选华支睾吸虫模拟抗原表位。方法应用噬菌体随机12肽库亲和筛选华支睾吸虫病患者混合血清IgG,经过3轮的淘筛,随机挑取蓝色噬菌斑进行扩增,以ELISA检测其免疫活性,挑选免疫活性较高的克隆进行序列分析及免疫学鉴定。结果8个阳性克隆测得6个DNA序列,Western-bloting显示6个单克隆噬菌体均可与华支睾吸虫患者血清反应,斑点免疫金银染色法有3个克隆可被华支睾吸虫患者血清识别。结论应用噬菌体肽库筛选技术可以获得华支睾吸虫模拟抗原表位。  相似文献   

9.
目的 从噬菌体展示随机肽库中筛选与内毒素结合的多肽序列,并进行鉴定.方法 以内毒素脂多糖(lipopolysaccharide,LPS)为靶分子对噬菌体展示随机十二肽库进行4轮亲和筛选,获得与LPS结合的噬菌体克隆,应用结合实验和克隆斑抑制实验进一步确证.挑选结合力强的克隆进行DNA测序,推导出呈现的多肽序列,应用生物信息学软件进行多肽序列分析和同源性分析.结果 经4轮亲和筛选从噬菌体展示随机十二肽库中筛选获得了86个克隆,挑选12个结合力强的克隆进行DNA序列测序及生物信息学分析,结合本项目组的噬菌体展示随机七肽库筛选结果推导出呈现的多肽序列为HWQWPHWSPPP(命名为P11肽).检索相关数据库发现此肽序列未被申请专利,体内约908种蛋白与其结构相匹配,其中包含有与LPS相互作用的位点.结论 通过对噬菌体展示随机肽库的淘选,获得与LPS结合的高亲和性多肽,为进一步以这些多肽为先导物进行定向进化研究提供了实验依据和结构基础.  相似文献   

10.
应用噬菌体展示技术筛选缺氧诱导因子-1α相关肽   总被引:2,自引:0,他引:2  
目的:应用噬菌体展示12肽库筛选低氧诱导因子—α(HIF—α)相关肽。方法:以抗HIF—α单克隆抗体(HIF—αmAb)为配基,采用亲和免疫法从随机12肽库中筛选与抗体特异结合的噬菌体。在筛选过程中,逐轮提高HIF—αmAb的稀释度并增强洗脱强度。3轮筛选后,随机挑取10个克隆测序。通过膜斑点印迹(Dot-ELISA)进行特异性结合鉴定。结果:经过3轮筛选后,特异性结合的噬菌体得到有效的富集,并且Dot-ELISA反应阳性逐轮增强。测序后发现有4个克隆的序列完全相同,其12肽氨基酸序列为GPHHYWYHLRLP。结论:噬菌体展示肽库技术可以用于筛选HIF—1相关肽,并为后续的活性鉴定打下基础。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

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.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
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   

20.
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   

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