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1.
湖北白猪胃蛋白酶原A基因cDNA克隆与序列分析   总被引:1,自引:0,他引:1  
根据Genebank公布的J04601猪胃蛋白酶原A序列,进行了引物的设计和筛选,通过RT-PCR获得了湖北白猪的胃蛋白酶原A的cDNA序列全长,共1 227 bp(已提交Genebank,登录号EF108301),其具有一个长度为1 158 bp的读码框,编码385个氨基酸,其中包含15个氨基酸组成的信号肽,成熟的胃蛋白酶原A由370个氨基酸残基组成.与J04601比较,核苷酸和氨基酸相似性分别为99.3%和98.7%.经PredictProtein分析表明,核苷酸和氨基酸的改变没有造成蛋白质二级结构和功能的变化;并对胃蛋白酶原A基因密码子使用频率和mRNA的二级结构进行了分析,为其载体和宿主的选择以及基因的改造奠定了分子生物学基础.  相似文献   
2.
Yellow catfish (Pelteobagrus fulvidraco) is an important commercial species with high aquaculture potential in China. To better understand the process of digestive functioning of gastric gland development during the larval from 1 dph (day post‐hatching) to 30 dph, real‐time PCR was used to detect and quantify the pepsinogen and H+/K+‐ATPase gene expression in P. fulvidraco. These data were also compared with the adult situation. The results showed that the expression of pepsinogen and H+/K+‐ATPase genes in P. fulvidraco larvae both started at 1 dph, though the expression level was very low until 3 dph. The quantification of pepsinogen gene expression increased significantly from 4 to 8 dph, increased fluctuantly from 8 to 23 dph and rose sharply from 23 to 30 dph. In comparison with adult fish, there were no significant differences with larvae at 5 and 23 dph. However, data of 10 and 30 dph larvae were obviously higher than those of adult group. H+/K+‐ATPase gene expression increased linearly from 1 to 30 dph. However, it was significantly lower than that of adult. The results show that P. fulvidraco larvae have an earlier functional stomach, though the function of the stomach is still not perfect. There is a gradual acidification environment within the stomach during the P. fulvidraco larvae development. Based on these results, we suggest that the weaning time for P. fulvidraco larvae would be much better after 23 dph.  相似文献   
3.
本研究旨在探寻胃蛋白酶(pepsinogen,PEP)基因的等位基因及其基因型在不同食性驯化表型鳜(Siniperca chuatsi)群体中的分布情况.通过2周食性驯化,挑选出最易驯化和最不易驯化的2组,提取各组鳜鳍条组织DNA,采用PCR产物直接测序法(direct sequencing,DS)、限制性片段长度多态...  相似文献   
4.
鳜胃蛋白酶原基因cDNA全长的克隆与序列分析   总被引:4,自引:2,他引:4  
吴雪峰  赵金良 《水产学报》2008,32(6):971-976
利用RT–PCR和cDNA末端快速扩增法(RACE)克隆鳜(Siniperca chuatsi)胃蛋白酶原基因cDNA全长序列,并对该基因的结构特征和系统进化关系进行了分析。鳜胃蛋白酶原基因cDNA序列全长1367 bp,5′端非翻译区43 bp,3′端非翻译区187 bp,开放阅读框(ORF)1137 bp,共编码378个氨基酸。鳜胃蛋白酶原氨基末端存在信号肽和激活肽序列,序列中含有催化活性必需的2个天冬氨酸残基和构成二硫键的6个半胱氨酸残基。鳜胃蛋白酶原氨基酸序列与其他脊椎动物胃蛋白酶原氨基酸序列的同源性为59.9%~91.2%,表明胃蛋白酶原基因在脊椎动物的长期进化中比较保守。鳜胃蛋白酶原基因的成功克隆不仅为进一步研究该基因的时空表达奠定基础,而且为鱼类胃蛋白酶原的分子特征和进化提供了新的资料。  相似文献   
5.
The measurement of serum pepsinogen concentrations by enzymatic method and immunoassay provides diagnostic values and should be helpful in the detection of gastric diseases related to a rise of blood pepsinogen. In the present study, the correlation between a conventional enzymatic method and a recently developed radioimmunoassay (RIA) for serum pepsinogen A was investigated. A total of 123 sera samples of porcine foetuses (n = 28), adult healthy pigs (n = 56), pigs with parakeratosis (n = 25) and pigs with ulceration of the pars oesophagea (n = 14) were tested. Overall, there was a slight correlation between the two methods (r = 0.60). In relation to individual animal groups, the correlations (r) were 0.39 (P>0.05), 0.74 (P<0.001), 0.19 (P>0.05) and 0.34 (P>0.05) in foetuses, healthy pigs, pigs with parakeratosis and pigs with ulcers, respectively. In both methods, pepsinogen concentrations (means+/-SE) were significantly higher (P<0.05) in pigs with parakeratosis (1778 +/- 86.00 mUTyr/L; 690 +/- 53.00 ng/mL) and in pigs with ulcers (2026 +/- 153.00 mUTyr/L; 1747 +/- 94.00 ng/mL) when compared to healthy pigs (935 +/- 58.00 mUTyr/L; 275 +/- 35.00 ng/mL). The proteolytic method gave a significant increased activity (P<0.05) in foetuses (1150 +/- 82.00 mUTyr/L) vs. (935 +/- 58.00 mUTyr/L) in healthy adult pigs, indicating an additional proteolytic activity in the sera of foetuses or neonates.  相似文献   
6.
pH值对胃蛋白酶原激活率影响的研究   总被引:11,自引:0,他引:11  
采用 2 4头平均体重 5.2 5kg的 2 8± 1日龄断奶杜×长大杂交仔猪 ,分成 4个处理组 ,在玉米豆粕型基础饲粮 (对照组 )中分别添加 1 % Na HCO3、 0 .6% HCl、 2 .4 % HCl,饲养仔猪 3周后于晨饲后 1 h屠宰 ,测定胃内容物 p H和胃内容物中胃蛋白酶原激活率。结果表明 ,添加 1 % Na HCO3使胃内容物 p H值上升 ,而添加 0 .6% HCl、 2 .4 % HCl则使胃内容物 p H值下降 ,胃内容物 p H值越低 ,胃蛋白酶原激活越快。在体外试验中 ,随 p H值下降 ,胃蛋白酶原激活率呈三次曲线上升。上述结果表明 ,胃蛋白酶原激活率与 p H值有关 ,p H值越低 ,胃蛋白酶原激活率越高  相似文献   
7.
目的 探讨木香顺气散联合恒温雷火灸治疗萎缩性胃炎的临床疗效及对患者血清胃泌素-17(gastrin-17,G-17)、胃蛋白酶原(Pepsinogen,PG)的影响。方法 将萎缩性胃炎患者90例随机分为对照组和观察组,各45例。对照组口服雷贝拉唑,20 mg/次,早7点与晚9点服用;阿莫西林:1 g/次;克拉霉:0.5 g/次,均早餐与晚餐1 h后服用。观察组在对照组基础上采取木香顺气散与恒温雷火灸治疗,木香顺气散:8 g/次,三餐前开水冲服;恒温雷火灸:取双侧足三里、神阙、中脘四穴,1次/d,10~20 min/次。两组患者均连续治疗2周,比较两组患者治疗后中医症状积分、临床疗效及幽门螺杆菌(Helicobactor pylori,Hp)转阴率,检测两组患者治疗前后的G-17及PGI、PGⅡ、PGⅠ/PGⅡ比值水平。结果 观察组总有效率为95.56%,明显高于对照组的77.78%(P<0.05)。治疗后,两组患者中医症状积分均较治疗前下降,且观察组症状积分显著低于对照组(P<0.01);两组患者G-17、PGⅠ、PGⅠ/PGⅡ比值水平均较治疗前升高,观察组PGⅡ较治疗前升高(P<0.01),且观察组G-17、PGI、PGⅡ、PGⅠ/PGⅡ比值水平均高于对照组(P<0.01);观察组Hp根除率高于对照组(P<0.01)。结论 木香顺气散联合恒温雷火灸治疗萎缩性胃炎,可促进患者血清G-17及PG水平的提高,避免胃黏膜进一步萎缩,提高了综合疗效。  相似文献   
8.
3种鳜鱼消化道结构与胃中泌酸胃酶细胞分布比较   总被引:2,自引:0,他引:2  
利用石蜡切片技术比较了鳜鱼、斑鳜和杂交鳜(斑鳜♀×鳜鱼♂)胃、幽门盲囊、肠道结构特征。3种鳜鱼胃壁均由黏膜层、黏膜下层、肌层组成,黏膜层内能看到固有层;其中,鳜鱼、杂交鳜胃黏膜层相对厚度0.30±0.09、0.30±0.11,斑鳜胃黏膜层相对厚度较薄,约0.21±0.13。肠道由黏膜层、黏膜下层和肌层组成,黏膜层表面含有绒毛,绒毛层含有杯状细胞;鳜鱼与杂交鳜褶皱数、杯状细胞密度间差异不显著(P0.05),但显著大于斑鳜(P0.05)。鳜鱼、斑鳜和杂交鳜幽门盲囊平均数目分别为(2.138±0.173)个/μm2、(0.793±0.132)个/μm2和(1.098±0.218)个/μm2。幽门盲囊结构与肠道相似,3种鳜鱼的褶皱数目差异不显著(P0.05),但斑鳜杯状细胞密度显著小于鳜鱼和杂交鳜(P0.05)。同时,利用原位杂交技术比较了3种鳜鱼胃中泌酸胃酶细胞的分布特征,3个胃蛋白酶原基因探针均出现紫色杂交信号,且均位于胃黏膜层。同种鱼中,不同基因探针杂交信号细胞密度差异不显著(P0.05);不同种类间,相同基因探针杂交信号细胞密度大小顺序均为鳜鱼=杂交鳜斑鳜,且相互间差异显著(P0.05)。消化道结构与泌酸胃酶细胞分布差异为鳜鱼消化生理学比较研究提供了基础资料。  相似文献   
9.
Extract

The heifer was born in September, 1950, and a week later a dripping navel was observed which persisted for about three months and then appeared to clear up. At the beginning of June, 1951, further symptoms were seen and professional advice was sought on 3rd July, 1951.  相似文献   
10.
The purpose of the study was to investigate the prevalence of gastric lesions and to provide diagnostic values for serum pepsinogen in non-infected pigs and in pigs with gastric disease. In an abattoir survey, the pepsinogen concentrations were measured in the serum from 62 non-infected pigs, 33 pigs with gastric lesions and 17 pigs infected with Hyostrongylus rubidus, using a specific radioimmunoassay (RIA). The mean (±SE) pepsinogen concentrations in the serum of non-infected pigs, in pigs with gastric ulcers, and in pigs with a heavy H. rubidus infection were 630.8±39.2 ng/ml, 1084.5±166.2 ng/ml and 1095.2±102.3 ng/ml, respectively (p<0.05). Because of the higher concentrations of pepsinogen in the blood of pigs with gastric ulcers or parasitic infections, it is suggested that the measurement of serum pepsinogen by RIA may be an effective biochemical approach to the diagnosis of chronic gastric disorders in pigs.  相似文献   
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