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1.
目的 分析候选基因Agouti的多态性,揭示染色体工程小鼠毛色差异的分子机制。方法 首先,用测色仪检测小鼠的毛色差异。其次,利用DNA芯片进行全基因组扫描确定候选基因Agouti。最后,运用生物信息学软件分析Agouti基因cDNA序列和氨基酸序列的多态性,预测突变对蛋白结构和功能产生的影响。结果 发现Agouti基因cDNA序列上存在5个SNPs,使Agouti信号蛋白产生了3个错义突变。生物信息学分析发现,其中一个错义突变使该蛋白丢失了一个β折叠,并且其三级结构发生改变,最终导致与受体结合的能力相较于野生型有所下降。结论 本研究在毛色基因Agouti的编码区发现了一个新的错义突变,该突变使Agouti信号蛋白与受体结合能力下降,最终导致小鼠的毛色由浅灰色变为深灰色。  相似文献   

2.
目的 克隆获得黄花蒿MEP途径中必需关键酶——羟甲基丁烯基-4-磷酸合成酶基因(HDS),并进行生物信息学分析和功能互补分析研究。方法 对已知的其他种子植物HDS基因的核苷酸序列进行多重序列比对,选取保守区域设计简并引物,利用同源扩增和cDNA末端快速扩增技术从黄花蒿中获得目的基因;利用BLAST进行序列比对,ORF Finder寻找开放阅读框,并用MEGA3.0中的临位相联法构建进化树。结果 得到1条长2 324 bp的HDS cDNA序列,其ORF框长1 854 bp,编码617个氨基酸残基的蛋白;生物信息学分析显示,黄花蒿HDS基因AaHDS与其他种子植物来源的HDS高度同源;功能互补分析表明,AaHDS能互补突变菌株Escherichia coli MG1655 ara<>HDS中缺失的HDS功能,使突变菌株恢复生长,证明AaHDS具有典型的HDS基因功能。结论 首次克隆获得黄花蒿HDS基因,为青蒿素的代谢工程研究提供相应的基础。  相似文献   

3.
目的 对建泽泻原萜烷型三萜类成分生物合成关键酶鲨烯合酶(squalene synthase,SS)进行基因全长的克隆和生物信息学分析。方法 以建泽泻总RNA为模板,运用同源克隆法和RACE技术克隆建泽泻SS基因的cDNA全长,并通过DNAMAN软件及ExPASy在线分析等方法对其进行生物信息学研究。结果 获得建泽泻SS基因全长cDNA,GenBank注册号为JX866770,序列分析表明,所克隆的cDNA序列全长为1 577 bp,包含一个长1 230 bp的开放阅读框架,编码409个氨基酸的蛋白,与其他药用植物具有较高的同源性。预测该蛋白的相对分子质量为4.68×104,等电点为5.97,无信号肽,包含2个富含天冬氨酸(DXXDD)的保守功能域。结论 首次克隆获得建泽泻SS基因的全长cDNA,为泽泻原萜烷型三萜类成分生物合成途径阐明与生物工程应用提供科学依据。  相似文献   

4.
目的 获取金荞麦总黄酮合成途径的关键酶查尔酮异构酶(chalcone isomerase,CHI)基因的全长序列,并进行序列分析;对花期金荞麦CHI基因在各组织中的表达与总黄酮量进行分析。方法 利用同源克隆技术获得金荞麦查尔酮异构酶基因(FdCHI)的cDNA序列;采用半定量RT-PCR对CHI表达量进行分析,并采用AlCl3法测量总黄酮量。结果 金荞麦FdCHI基因cDNA包含一个750 bp的ORF,编码249个氨基酸,命名为FdCHI。生物信息学分析表明该编码蛋白与其他植物CHI氨基酸序列同源率较高。FdCHI在花期金荞麦不同组织中的表达量分析表明,其表达量花>根>叶>茎,总黄酮量为花>叶>茎>根。结论 在金荞麦中首次获得CHI基因的cDNA序列,编码蛋白具有CHI同源蛋白的典型特征。FdCHI基因在金荞麦茎、叶和花中的表达量与总黄酮量具有相关性,但在根中表达量与总黄酮量相关性较小。  相似文献   

5.
目的 获取滇重楼甾体皂苷合成途径关键酶环阿屯醇合酶基因(PpCAS)的全长cDNA序列,并进行序列分析。方法 利用同源克隆和RT-PCR技术获得PpCAS基因保守片段,采用RACE技术获得PpCAS基因的3’及5’末端序列,并采用生物信息学方法进行序列分析。结果 PpCAS基因全长cDNA为2 309 bp,其开放阅读框(ORF)为2 283 bp,可编码760个氨基酸的蛋白质;PpCAS推导的蛋白质相对分子质量为8.69×104,等电点(pI)为6.54;其氨基酸序列与GenBank中其他植物CAS的同源性在60%~83% PpCAS蛋白。结论 从滇重楼中首次获得PpCAS基因cDNA全长序列,该基因具有CAS同源基因的典型特征。  相似文献   

6.
目的 寻找生川乌的毒性基因,探讨其毒性机制。方法 根据国际 ICH 的要求,在 SPF 实验条件下采用生川乌水煎液 ig 昆明种小鼠进行毒性实验。采用基因表达谱技术,就生川乌对小鼠5种脏器的毒性进行全基因组描绘,应用 Cluster、GO 和 Pathway 等生物信息学手段对获取的数据进行综合分析并进行定量 PCR 验证。结果 生川乌明显影响小鼠黏着斑 (Focal adhesion) 通路中的黏附素 (ECM)、局部黏附激酶 (FAK) 和 GTP 结合蛋白 (Cdc42) 等关键基因。结论 生川乌可能是通过影响小鼠 Focal adhesion 信号通路的关键基因而引起毒性,最终导致毒性的产生。  相似文献   

7.
目的 克隆刺五加的环阿屯醇合酶(cycloartenol synthase,CAS)基因,并对其进行生物信息学和表达分析。方法采用cDNA末端快速扩增(rapid amplification of cDNA ends,RACE)技术克隆刺五加CAS基因的全长cDNA序列。运用生物信息学方法对该基因进行分析,预测其编码蛋白的结构与功能,并通过RT-PCR法检测CAS在不同生长发育时期和不同器官中的表达情况。结果 刺五加CAS基因的cDNA全长为2 758 bp,开放阅读框长2 277 bp,编码758个氨基酸的蛋白,包含三萜合成酶的标志性序列。CAS蛋白无跨膜区域,定位于细胞质中。RT-PCR的结果显示,刺五加CAS基因在各时期和器官中均有表达,但表达量具有显著差异(P<0.05)。其中果实基本成熟期的表达量最高,是最低量萌芽期的1.56倍,各器官中,叶片的表达量最高,是最低量叶柄的1.37倍。结论 首次分离并报道了刺五加的CAS cDNA克隆,并证实其在不同生长发育时期和不同器官中的表达量不同,为进一步研究CAS对刺五加皂苷量的影响和表达调控奠定基础。  相似文献   

8.
目的 建立金黄地鼠和白化地鼠遗传生化基因位点.方法 选用小鼠和大鼠的遗传生化基因位点,采用蛋白质和同工酶醋酸纤维电泳的方法,对金黄地鼠和白化地鼠进行生化基因位点检测.结果 建立了金黄地鼠和白化地鼠25个生化基因位点,分析金黄地鼠和白化地鼠遗传生化基因位点的多态性,为进一步研究金黄地鼠白化突变系的遗传机理奠定基础.结论 金黄地鼠生化基因位点存在多态性,白化地鼠与金黄地鼠生化基因位点存在差异.  相似文献   

9.
目的 对怀地黄3-酮酯酰CoA-硫解酶(Rehmannia glutinosa f. hueichingensis 3-ketoacyl CoA-thiolase,RghKAT)cDNA全长基因进行克隆及分析,为怀地黄分子育种提供候选基因和理论依据。方法 根据其他植物ARGOS基因序列的保守结构域设计简并引物,采用RT-PCR和RACE技术,获得RghKAT cDNA全长序列;通过生物信息学技术对其核苷酸序列和氨基酸序列进行比对;利用实时荧光定量PCR技术检测了其在2个时期、10个组织的表达。结果 RghKAT基因全长1 713 bp,包含了1 395 bp的开放阅读框(ORF),编码464个氨基酸;同源比对和系统进化分析表明,RghKAT的核苷酸序列与葡萄、番茄、毛果杨、拟南芥和小麦的KAT核苷酸序列同源性分别达84%、82%、82%、79%、73%;RghKAT编码的氨基酸序列与矮牵牛、葡萄、黄瓜、拟南芥和小麦的KAT氨基酸同源性分别为88%、88%、86%、87%、78%;各物种KAT酶进化树符合物种进化规律;理化性质表明该蛋白为略成碱性的稳定蛋白质,蛋白质二级结构主要由α-螺旋、不规则卷曲、β-折叠和β-转角构成;在N端存在一个由70个氨基酸残基组成的信号肽;RghKAT蛋白三维结构具有硫解酶典型的特征序列;表达谱分析表明,RghKAT mRNA在各时期、各组织中均有表达,盛花期花瓣中表达最强,而在幼苗期叶中表达量最低。结论 成功克隆了RghKAT cDNA全长序列,具有KAT基因的结构特性及其产物硫解酶典型的特征序列,其在盛花期花瓣中表达量最高。  相似文献   

10.
目的 克隆刺五加亚精胺合成酶(spermidine synthase,SPDS)基因,并分析内生真菌对其表达的影响。方法 采用cDNA末端快速扩增(rapid amplification of cDNA ends,RACE)技术克隆刺五加SPDS基因全长cDNA序列。运用生物信息学方法对该基因进行分析。RT-PCR法检测内生真菌菌株P116-1a、P116-1b、P109-4和P312-1对SPDS基因表达的影响。结果 刺五加SPDS基因的cDNA全长为1 541 bp,开放阅读框长1 002 bp,编码333个氨基酸的蛋白,包含SPDS家族的基本结构和标志性序列。RT-PCR结果显示,内生真菌可显著提高刺五加SPDS基因的表达量(P<0.05),最大表达量出现在菌株P116-1b回接90 d时,是对照的2.06倍。结论 首次克隆了刺五加SPDS基因的cDNA全长序列,并证实内生真菌可显著提高刺五加SPDS基因的表达,为阐明内生真菌提高刺五加三萜皂苷量的机制及刺五加的抗逆性改良奠定了基础。  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.
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   

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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