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81.
AIM: To study the molecular biological mechanism and signal transduction pathway of interleukin-1β (IL-1β)-induced apoptosis in A375-S2 melanoma cells. METHODS: Photomicrocropy showed typical apoptotic changes. The cytotoxic effect of IL-1β in vitro and influences of caspases in this effect were measured by MTT assay. The cytotoxicity of cells was assessed by LDH-based assay. Degradation of DNA was detected by agarose gel electrophoresis. RESULTS: The inhibitory effect of IL-1β on A375-S2 cell growth was in a dose and time-dependent manner, and cell death rate reached more than 90% at 72 h after treatment with 10-9mol/L IL-1β. The inhibitors of caspase-family, -1, -3, -8, -9, and -10, partially blocked cell death at early stage. LDH assay showed that major IL-1β-induced cell death was apoptosis, and in a dose and time-dependent manner. Typical apoptotic DNA ladder was observed in agarose gel electrophoresis. CONCLUSION: IL-1β induced apoptosis in melanoma A375-S2 cells by activating caspase pathway.  相似文献   
82.
AIM: To investigate the expression of nucleotide excision repair gene ERCC1 and its relationship with PAH (polycyclic aromatic hydrocarbons)-DNA adducts in lung cancer tissues. METHODS: ERCC1 mRNA expression and the PAH-induced DNA adducts were detected in 150 lung cancer tissues, 120 adjacent lung tissues without cancer cells, 40 benign lung lesions and 40 normal lung tissues. The effects of some exposure factors on the expression of ERCC1 gene and the connection between ERCC1 and PAH-DNA adduct was analyzed. RESULTS: Reduced expression levels of ERCC1 were observed in 46 of 150 (30.7%) lung cancer specimens and 1 of 40 (2.5%) normal lung tissues. Smoking may suppress the expression of ERCC1 gene. The level of PAH-DNA adduct was negatively correlated with the expression of ERCC1 gene, the Spearman coefficient was -0.648, P<0.01. CONCLUSION: ERCC1 is an important nucleotide excision repair gene and may participate in the repair of DNA damage, such as PAH-DNA adduct. Low expression of ERCC1 may play an important role in the development of human lung cancer.  相似文献   
83.
AIM: To study the effect of propolis on the expression of CD54 and activation of NF-κB p65 in lung tissue of acute lung injury (ALI) rats. METHODS: 40 male Wistar rats were divided into 5 groups: normal control, model control, dectancyl group, water soluble derivative of propolis (WSP) group and ethanol extracted propolis (EEP) group. ALI animal model was performed by oleic acid and LPS twice attack. The pathologic slice was observed with light microscope and the NF-κB p65 activity and CD54 expression were tested by immunohistochemistry (SABC and SP). RESULTS: Both EEP and WSP antagonized the lung edema, decreased the inflammation and inhibited the expression of CD54 and activation of NF-κB p65. CONCLUSION: The increase in the expression of CD54 and the activation of NF-κB p65 in the lung tissues of ALI were involved in the formation of ALI. Propolis ameliorated the lung damage, which maybe related to the inhibition of CD54 expression and NF-κB p65 activation.  相似文献   
84.
对披碱草和野大麦及其杂种F1与BC1F1代的生物学及农艺特性进行了分析比较。结果表明,亲本野大麦生长发育节律较快,较早地开花结实,果后营养期较长,生育期74d,生长天数达206d,具有很强的分蘖能力;披碱草生长发育节律较慢,生育期124d,生长天数193d;杂种F1的生长天数介于双亲之间,生长动态偏向亲本披碱草,分蘖能力介于双亲之间;BC1F1代生长发育节律较F1代提早,不同株系生长天数不同,生长动态偏向轮回亲本野大麦,分蘖能力有较大的变异。杂种F1代表现出较强的杂种优势,BC1F1代产草量较F1代有所降低,不同株系间存在明显的差异。总体上,BC1F1代的生产性能倾向于轮回亲本野大麦。  相似文献   
85.
鸡AMPD1基因PCR-SSCP分析与相关性状的研究   总被引:4,自引:0,他引:4  
5′-磷酸腺苷脱氨酶1(AMPD1)是嘌呤代谢中的一种重要酶类,它的功能是催化AMP(一磷酸腺苷)脱氨,生成肌苷酸(IMP),从而影响肉质风味。试验采用单链构象多态性(PCR-SSCP)技术,以隐性白羽肉鸡、白来航蛋鸡和两个地方品种(北京油鸡、三黄胡须鸡)纯系鸡为试验材料,对AMPD1基因进行SNPs检测和基因类型判别。卡方检验结果表明: 除三黄胡须鸡和隐性白羽肉鸡、北京油鸡和白来航鸡间差异不显著(P>0.05)外,其他各品种间差异极显著(P<0.01)。AMPD1基因多态性与北京油鸡生产和屠体性状(活重、胸肌率、肌苷酸含量等)相关分析结果表明:肌苷酸含量在三种基因型间差异显著(P<0.05)。初步推断AMPD1可能为影响鸡肉中肌苷酸生成的主效基因或与主效基因相连锁。  相似文献   
86.
亚洲璃眼蜱唾液腺一新功能基因的克隆与测序   总被引:1,自引:0,他引:1  
HaB1是亚洲璃眼蜱雌成蜱唾液腺差异表达基因文库中的一个片段,根据其序列设计引物HaB1-GSP1和HaB1-GSP2,以唾液腺总RNA为模板,RACE法扩增获得HaB1的未知3′-末端。测定该末端序列,进行序列拼接,设计全长引物5-′CCAGTCCGAAGGAAGGGCG-3′和5-′TCTC-CGGGCACGTGAAGTGTC-3′。以cDNA第一链为模板,扩增获得基因全长。经核查表明,该基因为一新基因(登录号AY803896)。  相似文献   
87.
山羊孤雌胚胎的体外培养   总被引:2,自引:2,他引:2  
系统地研究了培养液微滴的大小、培养液体系及血清浓度对山羊孤雌胚胎早期体外发育的影响。结果表明,培养液微滴以较大体积(200~500μL)的培养效果较好;在3种培养液中,添加10%的NGS对山羊孤雌胚胎的体外发育效果较好,囊胚率分别可达62.79%(81/129)、53.52%(38/71)、13.64%(12/88);mCRlaa组囊胚发育率和囊胚细胞数显著低于SOFaa组和CRlaa组,SOFaa组优于CRlaa组,尽管SOFaa组和CRlaa组间无显著差异。在本试验条件下,以SOFaa培养液,山羊孤雌胚胎体外培养72h时加入10%的NGs,500μL微滴培养,其发育效果较好,囊胚率可达62.79%。  相似文献   
88.
为了研究断奶前补饲不同直/支链淀粉比开食料对羔羊瘤胃上皮发育的影响,选取24只体况良好、胎次一致、体重相近的10日龄羔羊(湖羊),将其随机分为3组,在饲喂相同母乳的基础上,分别补饲以纯木薯(CS)、玉米(MS)和豌豆淀粉(PS)(直/支链淀粉比分别约为0.11,0.27和0.44)为唯一淀粉来源的开食料。试验期间,每天4:00-19:00将羔羊抱入补饲栏补饲不同直/支链淀粉比的开食料,并且在6:30, 10:30和15:30将羔羊抱回母羊舍哺乳1 h。羔羊自由饮水,单栏饲喂,自由采食燕麦干草。56日龄时屠宰采样,采集瘤胃组织样品制作石蜡切片进行瘤胃乳头形态测定,采集瘤胃上皮样品提取RNA测定相关基因表达。结果表明:CS组羔羊瘤胃乳头长度和表面积显著(P<0.001)高于MS和PS组,CS和MS组羔羊瘤胃乳头宽度显著(P=0.001)高于PS组。对瘤胃上皮各层厚度统计显示,CS和PS组羔羊瘤胃上皮角质层厚度显著(P=0.001)高于MS组;CS和MS组羔羊瘤胃上皮颗粒层厚度显著高于(P<0.001)PS组;CS组羔羊瘤胃上皮棘基层厚度和总厚度显著(P<0.001)高于MS和PS组。qRT-PCR结果显示:不同直/支链淀粉比开食料显著影响羔羊瘤胃上皮CDK2和CDK6的mRNA表达量(CS>MS>PS, P<0.001);CS组羔羊瘤胃上皮细胞cyclin A和CDK4的mRNA表达量显著(P<0.05)高于PS组,但与MS组无显著差异;CS组羔羊瘤胃上皮cyclin D1的mRNA表达量显著(P=0.012)低于PS组,但与MS组无显著差异。CS组羔羊瘤胃上皮类胰岛素生长因子-1(insulin like growth factor,IGF-1)的mRNA表达量显著(P<0.001)高于MS和PS组,CS和MS组羔羊瘤胃上皮IGF-1R的mRNA表达量显著(P=0.001)高于PS组。上述结果表明:较高支链淀粉比开食料与较高直链淀粉比开食料相比,在瘤胃中较易降解生成挥发性脂肪酸,促进瘤胃上皮IGF-1及细胞周期蛋白mRNA的表达,进而有利于断奶前羔羊瘤胃上皮的发育。研究结果对制订羔羊营养方案具有重要指导意义。  相似文献   
89.
The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4–10 years of age, 410 ± 35 kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α‐amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air‐dried alfalfa and concentrate (70:30 as‐fed) in four subsequent periods of 14 days including 8 days of adaptation and 6 days of sampling. In each period and each meal, mares received concentrate either 30 min after (HC) or 30 min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic.  相似文献   
90.
The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB12, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (< 0.05) and increased the piglet weights (< 0.01) and litter weights (< 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (< 0.05) and tended to lower F:G ratio (= 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (< 0.05), and greater hepatic IGF‐1 protein (= 0.03) and muscular IGF‐1r gene expressions (< 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (< 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor.  相似文献   
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