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81.
过表达IL-6对山羊毛囊干细胞增殖和迁移的影响   总被引:1,自引:0,他引:1  
旨在通过在山羊毛囊干细胞(HFSCs)中过表达炎症因子白细胞介素6(IL-6),探讨其对山羊HFSCs增殖和迁移的影响,阐明MAPK/ERK信号通路在山羊HFSCs增殖和迁移过程中发挥的作用。本试验通过构建pXJ40-myc-IL-6过表达载体,瞬时转染到山羊HFSCs中,以空载体细胞为空白对照组。利用Western blot定量检测IL-6蛋白的表达,MTT法检测山羊HFSCs的增殖活力,划痕试验判定山羊HFSCs的迁移能力,最后采用Westernblot检测山羊HFSCs中MAPK/ERK和P38信号通路中关键激酶的表达水平。结果表明,将获得的IL-6过表达载体转染至山羊HFSCs3d后,与对照组比较,山羊HFSCs的增殖活力出现抑制,且抑制效果持续至第7天(P<0.05)。IL-6过表达载体转染至山羊HFSCs24h后,处理组划痕部位的愈合率达到84.2%,显著低于对照组的98.5%(P<0.01)。与对照组相比,MAPK/ERK信号通路中的关键激酶ERK1/2的磷酸化水平(p-ERK1/2)显著下调(P<0.01),P38信号通路中的关键激酶p38的磷酸化水平(p-p38)表达量上调,但差异无统计学意义(P>0.05)。综上所述,过表达IL-6基因对山羊HFSCs的增殖和迁移能力具有抑制作用,且过表达IL-6可能是通过MAPK/REK信号通路对山羊HFSCs增殖和迁移发挥负性调控作用,以上结果为揭示山羊HFSCs的迁移及组织修复机制的研究提供依据。  相似文献   
82.
以人型结核分枝杆菌 H37RV株基因组 DNA为模板 ,应用 PCR法对 ESAT- 6和 CFP10基因进行扩增 ,产物经纯化后与载体 PMD18- T连接、转化及酶切鉴定 ,亚克隆到原核表达载体 PGEX- 6 P- 1,构建原核重组表达质粒 ,转化入大肠杆菌 BL2 1中 ,以 1mmol/L IPTG诱导 ,进行 SDS- PAGE电泳。结果表明 ,ESAT- 6和 CFP10基因表达的融合蛋白相对分子质量分别为 32 0 0 0和 36 0 0 0 ,与实测相符。重组结核杆菌分泌蛋白 ESAT- 6和 CFP10的成功表达为结核病诊断及重组疫苗的构建打下了基础  相似文献   
83.
DA-6对野大麦幼苗光合作用和生长的影响   总被引:9,自引:0,他引:9  
研究了不同浓度的植物生长促进剂--DA-6对野大麦Hordeum brevisubulatum幼苗光合作用和生长的影响.在二叶期喷施较低质量浓度(5 mg/L,10 mg/L)的DA-6,可显著促进幼苗生长和叶绿素含量的提高;四叶期喷施较高质量浓度(20 mg/L,30 mg/L, 40 mg/L)的DA-6,可显著提高野大麦幼苗的生物量,其中20 mg/L和30 mg/L的处理,幼苗生物量分别提高55.1%和59.6%;光合作用能力分别提高12.8%和18.1%.  相似文献   
84.
The aim of this study was to measure the levels of inflammatory mediators in serum from horses naturally infected with Trypanosoma vivax. Banked serum samples collected during a previously reported T. vivax natural infection were used to analyze proinflammatory cytokines such as interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), and nitrite/nitrate (NOx) levels. We evaluated 12 serum samples from horses from a farm in southern Brazil, four of which had parasitological and molecular diagnoses for T. vivax and presented with clinical signs of disease. Cytokines were assessed by quantitative sandwich enzyme-linked immunosorbent assay, and NOx was measured using the modified Griess method. Levels of IFN-γ, TNF-α, IL-1, IL-6, and NOx were increased in serum of infected animals compared to that in noninfected animals. Therefore, infection with T. vivax caused an increase in proinflammatory cytokines and nitric oxide content.  相似文献   
85.
为确定最适用于金桔幼果生长的植物生长调节剂种类及浓度,在金桔第二批花期后幼果膨大期,分别用4种浓度梯度的赤霉素(GA3)、6-苄氨基嘌呤(6-BA)和芸苔素(BR)对金桔果树进行喷施试验,结果表明:各处理果实的横径增加2.47%-12.21%,纵径增加6.33%-16.33%,可溶性蛋白含量增加1.07-1.87倍,过氧化物酶活性提高1.21-5.16倍,有9个处理可溶性糖含量增加,7个处理的还原糖含量提高,9个处理的果形指数增大,各处理对幼果果柄长度无显著增大。对处理后的8个相关品质指标进行主成分分析,结果表明T7(60 mg/L 6-BA)处理更有利于金桔幼果的生长。  相似文献   
86.
To support their combined use, the objective of the study was to evaluate the effects of benazepril and pimobendan on serum angiotensin‐converting enzyme (ACE) activity in dogs. A total of 48 healthy beagle dogs were randomized into four groups (= 12 per group) in a parallel‐group design study: A (control, placebo twice daily (BID)); B (0.5–1.0 mg/kg benazepril once daily (SID) in the morning, placebo in the evening); C (0.25–0.5 mg/kg benazepril BID); D (0.25–0.5 mg/kg benazepril and 0.125–0.25 mg/kg pimobendan, both BID). The test items were administered orally for 15 days. Serum ACE activity was measured on days 1 and 15. Groups B, C and D had significantly lower average serum ACE activity compared to baseline and to the control group, on both days 1 and 15. There were no significant differences in average ACE activity between groups B, C and D. Noninferiority of group C to B was demonstrated. In conclusion, 0.25–0.5 mg/kg benazepril administered BID produced noninferior inhibition of serum ACE activity compared to 0.5–1.0 mg/kg benazepril dosed SID. Pimobendan had no significant effect on benazepril's action on serum ACE activity. The results support the use of benazepril BID in dogs and in combination with pimobendan.  相似文献   
87.
贡成良  张传溪 《蚕业科学》1998,24(3):162-169
将pGEX-3X中由血吸虫(Schistosomajaponicum)编码的26kD谷胱甘肽转移酶基因Sj26和凝血因子Xa凝血酶位点引入到BacPAK8构建了融合表达杆状病毒转移载体BacSj26;将28kD的谷胱甘肽转移酶基因通过PCR突变消除终止密码后,引入BacPAK8构建了融合表达转移载体BacGST28。将P(MFHT)中的6×His序列克隆进BacPAK8,从而构建了6×His融合表达转移载体BacHis。这些融合表达转移载体的构建,为表达产物的一步纯化奠定了基础。  相似文献   
88.
AIM: To study the effect of late reperfusion on apoptotic cardiomyocytes in the risk area of acute myocardial infarctin in dogs. METHODS: The experiment was divided into three groups: sham operation group, acute myocardial infarction (AMI) group, and late reperfusion (LR) group. Apart from sham operation group, the other two groups were subjected to left anterior descending branch of coronary artery ligation. The acute myocardial infarction group was only subjected to ligation for 12 hours, late reperfusion group was subjected to ligation for 6 hours following by 6 hours of reperfusion. The cardiomyocyte apoptosis was measured by TUNEL assay. Immunohistochemistry and Western blotting analysis were used to detect the expression of Bcl-2 and Bax protein. RESULTS: The number of apoptotic cardiomyocytes in late reperfusion group was much less than acute myocardial infarction group (P<0.05), and increased significantily as compared with sham operation group (P<0.01). The expression of Bcl-2 protein was enhanced gently in late reperfusion group in contrast to acute myocardial infarction group, but no significant difference in the two groups (P>0.05) was observed, although it was much more in the two groups than that in sham operation group (P<0.01). The expression of Bax protein in late reperfusion group was much higher than that in sham operation group (P<0.01), and was lower than that in acute myocardial infarction group (P<0.05). CONCLUSION: Late reperfusion reduces cardiomyocyte apoptosis in the risk area of acute myocardial infarction. The mechanism may be that late reperfusion can decrease the expression of Bax protein.  相似文献   
89.
ABSTRACT

1. The relationships between the main components of the body and body protein among males and females of BUT 6 (BUT) and Hybrid Converter (HYB) turkey strains were examined.

2. The weights of breast meat, breast skin, drumstick meat, drumstick skin, thigh meat, thigh skin and wing-plus-skin as well as the head, neck, feet, blood, heart, liver and gizzard were measured at different stages of growth after which all components of each bird were minced together in order to determine the feather-free body protein weight of each bird sampled. Using the weights of the components and the protein content of each bird the allometric relationships between the components and body protein were determined and then compared for each strain x sex combination.

3. By excluding the breast weights at day-old and at 7 d, the remaining points produced an acceptable allometric relationship (R2 = 0.992). Thigh weight could be predicted for all strain x sex combinations using one allometric equation, as could drumstick skin weight. Breast and thigh skin weights differed between males and females. Females of the HYB strain exhibited heavier drumstick and wing-plus-skin weights at a given body protein weight than the other three strain x sex combinations. These differences in both the constant term and regression coefficient in the allometric equations between genotypes are probably due to differences in the amount of lipid that is deposited in these tissues.

4. Sexes differed in the allometric relationships for head, feet, heart and liver, while breeds differed in gizzard weight. A common relationship between the four genotypes could be used to predict the weight of blood in the carcass.

5. The allometric equations fitted to the data in this trial enable the accurate prediction of the weights of the different physical components given the weight of body protein.  相似文献   
90.
试验旨在构建犬α6干扰素毕赤酵母表达系统,并对其进行优化和筛选,以期获得高活性的重组犬α6干扰素(CaIFN-α6)。根据CaIFN-α6基因序列,按毕赤酵母菌密码子偏好性对CaIFN-α6全基因序列进行优化与合成,用Xho Ⅰ和Not Ⅰ双酶切将其连接至载体pPICZαA中,构建pPICZαA-CaIFN-α6重组表达质粒,转化大肠杆菌DH5α感受态细胞。提取质粒pPICZαA-CaIFN-α6并线性化,电转入酵母感受态细胞X33中制备重组菌。采用甲醇进行诱导表达,收集上清,超滤浓缩,最终获得纯化的重组CaIFN-α6。利用BCA法测得纯化后的CaIFN-α6蛋白浓度为1.5 mg/mL,Western blotting分析表明CaIFN-α6蛋白具有良好的反应原性,SDS-PAGE显示其纯度约在95%以上,MDCK/VSV法检测其效价为2.37×107 IU/mL,比活性为1.58×107 IU/mg。结果表明犬α6干扰素在毕赤酵母pPICZαA表达载体系统中成功表达,且具有较高的生物活性,为后期的犬病毒病的临床预防与治疗提供了良好的支撑。  相似文献   
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