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991.
It aimed to identify the differential methylation region (DMR) and differential methylation gene (DMG) through the analysis of the genome-wide methylation difference of the longest muscle of the sheep's back of different breeds of sheep,and laid the foundation for the analysis of the differences in sheep skeletal muscle development.In this study,one-year-old sheep(Tan sheep and Hu sheep and Tan-Hu F2) were sanned by the whole genome bisulfite sequencing method(WGBS).The degree of methylation and differentially methylated region in the whole genome DNA of longissimus dorsi(LD) muscle were studied to explore the difference of DNA methylation in level in sheep.The results showed that the methylation (mC) rates of cytosine (C) were 3.55%,3.18% and 3.56% in Tan sheep,Hu sheep and Tan-Hu F2,respectively.A total of 97 731 DMRs and 10 784 related DMGs were detected.In CG,CHH and CHG sequences,the methylation levels of the three groups were not significantly different.419 GO terms and 20 related signal pathways were detected by GO and KEGG analysis,respectively,which were showed to be significantly enriched in cellular process,cell part,binding,long-term depression,and so on.Five candidate genes,ACTA2、ROCK1、CALD1、MYH3 and MYH10 were sreened out in muscle tissues.This study provided genome-wide methylation of pattern of three groups (Tan sheep and Hu sheep and Tan-Hu F2).The results provided reference information for the epigenetic study of Tan sheep and screened candidate genes related to muscle development and meat quality.  相似文献   
992.
In order to identify the molecular markers related to alive litter size of Bama Xiang pigs,the genome-wide association study (GWAS) was used to map and screen the candidate genes affecting the alive litter size trait.Ear tissue samples of 297 Bama Xiang pigs with multiple parity records were collected,and DNA was extracted and genotyped by porcine 50K SNP beadchip.After quality control and genotype imputation,the alive litter size of Bama Xiang pigs were GWAS by Tassel.The results showed that the average number born alive per litter of Bama Xiang pigs increased gradually with the increasing of parity in the range of 1-9 parities.A total of 32 816 SNPs were obtained after quality control and filtration.8 SNPs related to alive litter size of Bama Xiang pigs were screened by genome-wide association analysis,which were significant at genome or chromosome level.Based on the enrichment analysis of the coding genes in the region between 500 kb upstream and downstream of the associated significant SNP loci,and the QTL regions and gene functions related to porcine reproductive traits,4 genes (CAPZB,MSH3,CITED2 and HSD17B7) were finally identified to be candidate genes related to alive litter size of Bama Xiang pigs.  相似文献   
993.
选用平均体重为(40±2)kg杜长大三元杂交去势公猪3头,按3×3的拉丁方进行试验设计,试验分3期,每期为7 d,采用全收粪法,研究不同蛋白质(CP)水平的氨基酸平衡日粮CP水平分别为14%、16%和18%)对氮、磷及能量代谢的影响。结果表明:不同蛋白质水平日粮处理间的氮表观消化率差异不显(著P>0.05),氮的沉积率以14%CP和16%CP组显著高于18%CP组(P<0.05),而14%CP和16%CP组之间无显著差异(P>0.05)。粪氮排出量14%CP日粮组显著低于16%CP和18%CP日粮组(P<0.05),16%CP日粮组和18%CP日粮组间无显著差异(P>0.05)。随着日粮蛋白质水平下降,生长猪的氮排出量、粪氮和尿氮均减少,总排泄氮中尿氮的比例较大,而粪氮则较少。不同蛋白质水平日粮对磷和能量的消化利用无显著影响(P>0.05)。  相似文献   
994.
4味中药及其与抗菌药的复方制剂的MIC测定   总被引:3,自引:0,他引:3  
用改进的试管两倍稀释法测定了黄连、鱼腥草、大青叶和苦参4味中药及其相互配伍(1:1)对标准大肠杆菌的最小抑菌浓度和4味中药与抗菌药配伍(1000:1)对临床分离鸡大肠杆菌的最小抑菌浓度。结果表明,4味中药及其相互配伍对大肠杆菌标准株有一定的抑制作用,其MIC值介于3.91—62.50mg/mL之间,其中大青叶和鱼腥草以1:l配伍对大肠杆菌抑菌效果最好,MIC为3.91mg/mL;对临床分离株,单方药中黄连抑菌效果最好,MIC为31.25mg/mL,24种复方药中,黄连和盐酸多西环素或加替沙星以1000:1配伍的抑菌效果最好,其MIC为3.91mg/mL。  相似文献   
995.
研究表明,金耳发酵液对四氧嘧啶诱导的糖尿病小鼠有降血糖作用,同模型对照组相比.大剂量组差异显著(P〈0.05);同时,大剂量组对糖尿病小鼠摄食、饮水量的减少及体重的增加均有显著影响(P〈0.05)  相似文献   
996.
AIM:To detect the mRNA expression of tissue factor (TF), urokinase-type plasminogen activator (u-PA) and urokinase-type plasminogen activator receptor (u-PAR) in the samples of hepatocellular carcinoma (HCC) and adjacent tissue, and to elucidate their association with clinical significance. METHODS:The mRNA levels of TF, u-PA and u-PAR in 27 human HCC tissue samples with their adjacent tissue samples and 27 normal liver tissues were detected by RT-PCR. The relationship between the mRNA expression and their clinic-pathological data were also analyzed. RESULTS:The expressive rate of TF, uPA and uPAR in HCC tissue samples was 62.96% (17/27), 70.37% (19/27), 77.78% (21/27), respectively and relative expression intensity of TF, uPA and uPAR were 0.567±0.268, 0.964±0.458 and 0.784±0.322, respectively, which were significantly higher than those in adjacent tissue group and normal liver group (P<0.05). TF, uPA and uPAR mRNA levels were all significantly higher in larger size and in the invasive and metastatic subgroup (P<0.05). There had positive relationship between the mRNA expressions of these three factors. CONCLUSION:The results indicate that TF, uPA and uPAR might play an important role in hepatic carcinogenesis, invasiveness and metastasis.  相似文献   
997.
998.
AIM: To study the level of serum cystatin C (Cys C) and its prognostic value in acute renal failure (ARF). METHODS: 215 critically ill patients were studied prospectively, and each blood sample was determined daily. Serum creatinine (Scr) was measured by enzymic method. Cys C was detected by particle-enhanced turbidimetric immunoassay (PETIA) and glomerular filtration rate (GFR) was estimated by Cockroft-Gault equation. ARF was diagnosed according to ADQI (RIFLE) criteria. RESULTS: 41 patients developed ARF to some degree, among which 7, 13 and 21 patients fulfilled R-, I-, and FLE-criteria, respectively. 21 were death and 20 survival in total 41 ARF patients. 174 patients without ARF served as controls. In patients with ARF, Cys C was significantly increased than that in patients who did not develop ARF (P<0.01). In different RIFLE criteria of ARF, serum Cys C was linearly correlated with serum creatinine (P<0.01), also [Cys C]-1 with estimated GFR (P<0.01). When ARF was diagnosed according to serum creatinine increased ≥150%, serum Cys C was demonstrated a highly diagnostic value to detect ARF as indicated by area under the curve (AUC) of the ROC curve of 0.983 (95% confidence interval, 0.960-1.006) (P<0.01). Logistic regression showed serum Cys C and Scr were not independently risk factors for the mortality of ARF (P>0.05). Also ROC analysis demonstrated serum Cys C and Scr had no predicting value of the fatality and survival in ARF (P>0.05). CONCLUSION: Serum Cys C is significantly increased in ARF and correlated well with the severity of ARF. Serum Cys C can be one of the detectable markers of ARF, but it is independent of the mortality and does not predict the prognosis of these patients.  相似文献   
999.
AIM:To investigate the effects of uremic serum of different molecular weight groups on gene and protein expression of connective tissue growth factor (CTGF) in human renal tubular epithelial cells.METHODS:The serum from 40 chronic renal failure patients and 20 healthy volunteers were collected and uremic serum was segregated to three groups: >10 000 D,5 000-10 000 D,<5 000 D by 10 000 D and 5 000 D molecular weight Centricon Plus 20 Centrifugal Filter Devices.The protein expression of CTGF was examined by Western blotting.The mRNA expression of CTGF was detected by RT-PCR.RESULTS:CTGF gene expression were increased in 2.5%-20% uremic serum groups compared with that in normal control group,and it was the highest in 10% uremic serum groups.CTGF gene expression was increased significantly in molecular weight >10 000 D and 5 000-10 000 D groups,and the highest was in >10 000 D group,but it was no significant difference in <5 000 D group compared with that in normal control group.CTGF protein was increased in different molecular weight uremic serum groups compared with that in normal control group,and gradually increased following the increasing of uremic serum concentration and it was the highest in molecular weight >10 000 D group.CONCLUSION:Human renal tubulointerstitial fibrosis was accelerated significantly by uremic toxin,especially molecular weight >10 000 D uremic toxin through promoting the gene and protein expression of CTGF in renal tubular epithelial cells in patients with chronic renal failure.  相似文献   
1000.
杨盘二孢激发子的分离及稳定性研究   总被引:1,自引:0,他引:1  
 从杨盘二孢的培养滤液和菌丝中获得2种激发子粗提物,分别测定其糖和蛋白质的含量,发现滤液激发子粗提物(CFE)糖和蛋白质的含量分别为41.07和40mg/mL,菌丝激发子粗提物(CME)糖和蛋白质含量分别为48.07和55mg/mL。滤液激发子粗提物对温度不敏感而对碱性条件敏感;菌丝激发子粗提物对酸碱不敏感而对温度敏感。用Sephadex G-100柱层析的方法初步纯化2种激发子,并且菌丝激发子粗提物过柱后得到2个活性组分J14和J25;滤液激发子粗提物过柱后获得2个活性组分L9和L16。将4个组分进行烟草叶片过敏反应和I-895杨酶活性的诱导,结果表明,菌丝激发子强活性物质集中在J14组分;而滤液激发子强活性物质集中在L9组分。  相似文献   
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