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1.
胰岛素是人体胰腺内胰岛β细胞分泌的一种激素,含有16种51个氨基酸,是一种小分子蛋白质,分子量为5700,有A和B两条多肽链,A、B链间有两个二硫键相连。A链有21个氨基酸残基,内部还有一个二硫键,连接第6与第11个氨基酸残基;B链有30个氨基酸残基。最初,胰岛素由动物胰腺中提取。  相似文献   

2.
田图磊  赵侠 《大家健康》2014,(9):330-331
Egr-1(earlygrowthresponsivegene-1,Egr-1)是重要的核转录因子,其编码多种蛋白,在调控细胞的生长、分化、发育、增殖、炎性反应等方面发挥重要作用,本文针对其基因结构及特点,生物学特性、与肿瘤、炎症及肝损伤的关系作一简要综述。Egr-1基因及其蛋白的结构与特点
  Egr-1基因编码的蛋白质是一种分子大小约在80000Da的核磷蛋白质,由533个氨基酸组成,其编码的蛋白质有3个重复的锌指结构域。Egr-1基因编码的蛋白质按功能可分为三个区,靠近N 端的314个氨基酸残基是磷酸化位点,该位点可调节Egr-1蛋白的活性,其中蛋白活化的调节区域位于3-280氨基酸残基;281-314区段氨基酸残基可起到抑制性调节Egr-1的作用,其为辅助转录因子NGFI-A的结合位点;Egr-1的核定位信号区位于315-330区段氨基酸残基;最重要的蛋白中心区域由331-426区段氨基酸残基组成,其可组成3个cys2-his2亚类锌指结构,能与被调控基因5 GCGGGGGCG3基因序列非特异结合,从而起到调控其转录的作用[1]。  相似文献   

3.
目的:研究氨基酸残基配型的肾脏移植中的意义。方法:按氨基酸残基配型模式,对395例肾移植患者进行分析,结果:按各位点单一配型同氨基酸残基配型比较发现,A位点从0MM的6.58%提高至2MM的29.11%,B位点从OMM的2.53%提高至2MM的20.0%,DR位点从OMM的4.81%提高至2MM的15.95%,两种配型方法之间有显著性差异(P<0.01),同样,综合HLA-A、B、DR六个位点亦是如此,结论:按照氨基酸残基配型将提高肾移植供受者的配合率,增加移植肾的存活率,降低排斥的发生率,DR六个位点亦是如此,结论:按照氨基酸残基配型将提高肾移植供受者的配合率,增加移植肾的存活率,降低排斥的发生率。  相似文献   

4.
目的了解细菌多肽应具备什么基本条件才能被人白细胞相关抗原(HLA)B27递呈而导致脊柱关节病。方法以来自衣原体热休克蛋白60、能与B27分子结合的9肽作为原型,用人工方法将9肽的每一个氨基酸残基均以另外19种氨基酸替换,将合成的180种9肽分别与B27T2细胞孵育,观察其与抗B27单克隆抗体B27M2的反应性。结果与B27分子结合的9肽其第2位氨基酸残基应是精氨酸,以其它19种氨基酸替换均使B27M2的反应性明显降低;第6,8,9位氨基酸残基的选择性亦较高,仅有6~8种氨基酸能诱导与B27M2的反应性;第3,5,7位氨基酸残基没有什么选择性,几乎任何一种氨基酸残基对B27M2反应性的影响均不大。结论第2,9位氨基酸残基是9肽与B27紧密结合所必需的,而第6,8位氨基酸可能与抗B27单克隆抗体的识别有密切关系  相似文献   

5.
肝癌单克隆抗体可变区基因的克隆及序列分析   总被引:2,自引:0,他引:2  
目的:获取抗人原发性肝癌单克隆抗体重、轻链可变区基因。方法:从分泌高亲和力的抗人原发性肝癌单克隆抗体的杂交瘤细胞株SM8.11中提取细胞的总RNA,以随机引物反转录合成cDNA,以特异引物进行PCR,扩增了单抗的重链可变区(VH)及轻链可变区(VL)基因,并进行了序列分析。结果:VH基因片段长度为351bp,编码117个氨基酸残基;VL基因片段长度为324bp,编码107个氨基酸残基。两者均有4个  相似文献   

6.
秦伟  孙新颜 《实用医技杂志》2006,13(7):1103-1103
脂肪酶(LIPA)是一个由420或449个氨基酸残基组成的单链糖蛋白,主要用于急性胰腺炎的诊断。由于LIPA检测方法的较大改进,LIPA对急性胰腺炎的诊断敏感性和特异性有了很大提高。LIPA对急性胰腺炎的诊断的灵敏性从56%~100%不等,特异性从42%~100%不等。  相似文献   

7.
目的:生物信息学的发展为通过在线软件预测新基因的相关信息提供了众多有重要价值的参考信息。文中利用生物信息学方法预测泛素结合酶2S( ubiquitin-conjugating enzyme 2S, UBE2S)生物学功能。方法以人肝癌HepG2细胞为材料,从构建的cDNA文库基因组中筛选和克隆了UBE2S基因。利用NCBI的BLAST在线分析工具分别对GenBank的非冗余核酸数据库和非冗余蛋白质数据库序列进行比对分析;采用NCBI ORF finder在线分析工具预测开放阅读框;利用ExPASy在线工具ProtParam统计基因中各种氨基酸含量,并预测理论分子量和等电点;应用ProtScale程序进行蛋白质的疏水性分析;蛋白质亚细胞定位采用在线工具( nibb.ac.jp/form.html)预测,通过NCBI数据库GenBank分析蛋白质保守结构域;采用Protfun在线工具预测UBE2S的功能分类;采用同源模型服务软件SWISS-MODEL预测UBE2S的三维结构;采用MEGA5.05软件进行系统进化树的构建。结果 UBE2S基因编码241个氨基酸,预测相对分子质量为23770,理论等电点为8.81。跨膜结构域分析表明,UBE2S蛋白不含跨膜位点;亚细胞定位预测,UBE2S蛋白具有生长因子、离心通道、结构蛋白功能的概率为8.904、0.313和0.291。同源性比较分析结果表明,其碱基序列与已经报道的其他12个物种的相似率为90%~97%,且符合种属之间的进化关系。结论 UBE2S蛋白结构和功能的分析不仅丰富了其家族基因信息,还将为后续肝癌发生发展的分子机制实验研究奠定基础。  相似文献   

8.
目的改进军队院校学员集体体检工作的护理组织管理,以提高体检效率和服务质量。方法第一,考虑学员体检后就餐问题,上门采血;第二,根据体检人员的数目及检查项目分组、设区、布台、制定体检流程,由导检护士实施全程管理。结果平均每次安排体检人数约为过去的1.6倍,体检时间由原来的平均9min/人次缩短为5.5min/人次,体检人员的平均满意度由2001年的84%上升为2005年的100%,医务人员对门诊体检管理的满意度也由80%上升到99.6%。结论采用这种管理方法能高效有序地完成集体体检工作。  相似文献   

9.
Fmoc固相合成神经降压素   总被引:1,自引:0,他引:1  
神经降压素是由13个氨基酸残基组成的生物活性多肽。实验以Fmoc氨基酸原料,采用固相合成方法,经N,N'-二环己基碳二亚胺/1-羟基苯并三唑缩合,三氟乙酸/二氯甲烷脱保护,并从Wang树脂上切割下来,粗肽得率为61.8%,经RP-HPLC纯化,获得纯度在98%以上的目标肽,其ESI—MS和氨基酸组分分析结果与理论值相符。  相似文献   

10.
目的预测肿瘤相关蛋白EIF4G1亚型的B细胞表位。方法下载EIF4G1蛋白各种亚型的氨基酸序列,以单参数(亲水性、可及性、柔韧性、抗原性)预测为基础,结合ABCpred和二级结构预测筛选等方法综合筛选EIF4G1蛋白质亚型特异性的B细胞表位。结果目前已知EIF4G1蛋白的亚型有5种,亚型间的氨基酸变化局限在一个由300个氨基酸形成的序列区域,亚型特异性的B细胞表位可能位于该区域的14~19、21~27、52~61、106~112、113~139、183~189、201~216和217~224位氨基酸残基区域内或附近。结论EIF4G1蛋白质亚型间存在特异性B细胞表位,这些表位对应用合成肽抗原检测蛋白质亚型和进行肿瘤患者的早期诊断具有重要指导意义。  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.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

20.
ANTI-PROLIFERATION EFFECT OF ORIDONIN ON HL-60 CELLS AND ITS MECHANISM   总被引:4,自引:0,他引:4  
Objcetive To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.  相似文献   

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