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621.
【目的】克隆小菜蛾Plutella xylostella NanosO基因PxnosO启动子,并验证其具有生殖腺特异性活性,以期应用于基因功能研究或转基因昆虫的构建,为小菜蛾等农业害虫的综合治理提供新的研究思路。【方法】根据小菜蛾基因组序列信息,利用PCR技术克隆NanosO的启动子并进行序列分析。构建PxnosO-EGFP表达质粒,利用脂质体细胞转染技术将PxnosO-EGFP和IE1-EGFP表达质粒转入到小菜蛾胚胎细胞系(Px-6)和草地贪夜蛾Spodoptera frugiperda卵巢细胞系(Sf9)中,通过激光共聚焦荧光显微镜观察和qRT-PCR技术分别定性和定量分析EGFP基因的表达,验证小菜蛾NanosO启动子的活性。【结果】克隆获得小菜蛾PxnosO (Px004767)启动子区序列,长1 743 bp。对启动子序列进行分析,发现该序列不仅包含启动子共有核心元件TATA box以及上游启动子成分CAAT box和GC box等,还包含有数十个转录因子结合位点。利用细胞转染技术,在PxnosO启动子驱动下成功地在Px-6和Sf9细胞系中表达外源基因EGFP。【结论】克隆了小菜蛾NanosO基因PxnosO启动子,在细胞水平上验证其能驱动外源EGFP基因的表达,为分析PxnosO在小菜蛾不同发育时期的表达模式和PxnosO启动子在体内的功能验证奠定基础。  相似文献   
622.
623.
Kukoamine A (KukA) is a spermine (SPM) conjugate with dihydrocaffeic acid (DHCA), with interesting biological activities. The four possible regioisomers of KukA, as well as a series of KukA analogs incorporating changes in either the SPM or the DHCA structural units, were evaluated for their antioxidant activity and their inhibitory activity on soybean lipoxygenase (LOX) and lipid peroxidation. The reducing properties of the compounds were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and found to be in the range 5–97.5%. KukA significantly inhibits LOX with IC50 9.5?μM. All tested analogs inhibited lipid peroxidation in the range of 11–100%. The most potent compounds KukA and its analog 3, in which the DHCA units had been replaced by O,O9-dimethylcaffeic acid units, were studied for their anti-inflammatory activity in vivo on rat paw edema induced by carrageenan and found to be of comparable activity to indomethacin. The results of the biological tests are discussed in terms of structural characteristics.  相似文献   
624.
625.
Chrysoperla agilis Henry et al. is one of the five cryptic species of the carnea group found in Europe. Identification of these species is mainly based on the distinct mating signals produced by both females and males prior to copulation, although there are also morphological traits that can be used to distinguish among different cryptic species. Ecological and physiological cryptic species-specific differences may affect their potential as important biological agents in certain agroecosystems. To understand the effects of temperature on the life-history traits of C. agilis preimaginal development, adult longevity and reproduction were studied at seven temperatures. Temperature affected the development, survival and reproduction of C. agilis. Developmental time ranged from approximately 62 days at 15 °C to 15 days at 30 °C. Survival percentages ranged from 42% at 15 °C to 76% at 27 °C. One linear and five nonlinear models (Briere I, II, Logan 6, Lactin and Taylor) used to model preimaginal development were tested to describe the relationship between temperature and developmental rate. Logan 6 model fitted the data of egg to adult development best according to the criteria adopted for the model evaluation. The predicted lower developmental threshold temperatures were 11.4 °C and 11.8 °C (linear model), whereas the predicted upper threshold temperatures (Logan 6 model) were 36.6 and 36.9 °C for females and males, respectively. Adult life span, preoviposition period and lifetime cumulative oviposition were significantly affected by temperature. The effect of rearing temperature on the demographic parameters is well summarized with the estimated values of the intrinsic rate of increase (rm) which ranged from 0.0269 at 15 °C to 0.0890 at 32 °C and the highest value recorded at 27 °C (0.1530). These results could be useful in mass rearing C. agilis and predicting its population dynamics in the field.  相似文献   
626.
目的:探讨MRI检查中发生幽闭恐惧症患者的心理特征及其心理疏导对策。方法:根据Marks的4条诊断幽闭恐惧症的标准,选择2008年1月~2011年6月在我院磁共振室检查的102例出现不同程度幽闭恐惧症且MRI检查无法顺利完成的患者,分析其临床症状,查找检查失败发生的原因,并进行心理疏导、改善检查环境、家属陪同检查、优化扫描时间、程序以及口服镇静药物等方法保证检查的顺利完成。对干预前后患者的生命体征和检查中不适症状发生情况的差异进行比较。结果:102例发生幽闭恐惧症的患者通过心理疏导、改善检查环境、家属陪同检查、优化扫描时间、程序以及口服镇静药物等方法实施有效的护理干预,第二次检查成功87例,第三次成功10例,5例患者放弃检查,有效率达95.1%,干预后患者的生命体征:呼吸、脉搏、收缩压、舒张压等较干预前有明显的减轻;检查中不适症状:心悸、头晕、窒息感、压抑感等在干预后也明显减轻,各项指标的干预前后的变化有统计学差异,P0.05。结论:积极有效的心理疏导护理可缓解MRI检查中幽闭恐惧症的不适症状,使多数患者顺利完成MRI检查。  相似文献   
627.
目的:比较Aβ在两种阿尔茨海默病转基因小鼠模型脑新皮质区分布的差异。方法:采用18月龄雄性APP/PSl双转基因(2×Tg-AD)小鼠与同龄同性别APP/PSl/tau三转基因(3×Tg-AD)小鼠,取新皮质区脑组织行6E10单克隆抗体免疫组化染色等方法显示Aβ阳性神经元及斑块,观察其分布与形态等的差异,图像分析系统定量比较其量的变化。结果:在新皮质区2×Tg-AD组Aβ阳性产物主要位于细胞外即细胞外Aβ(e Aβ),形成大量的老年斑,细胞内阳性产物少;而3×Tg-AD组Aβ阳性产物主要位于神经元细胞内即细胞内Aβ(i Aβ),但老年斑少见。结论:2×Tg-AD组与3×Tg-AD组Aβ阳性产物在新皮质区分布的差异可能反映了两种AD小鼠模型神经病理等改变的不同。  相似文献   
628.
目的:观察慢性肾小球肾炎血清基质金属蛋白酶9(matrix metalo protein-ase-9,MMP-9)、金属蛋白酶组织抑制剂1(tissue inhibitors of metalloproteinases,TIMP-1)的浓度与肾组织中MMP-9、TIMP-1表达的相关性,探讨慢性肾小球肾炎血清MMP-9、TIMP-1对肾脏纤维化的判断价值。方法:通过肾组织活检病理检查,将入选慢性肾炎的病例分增生组(A组)15例,纤维化组(B组)15例,另选10例志愿者作为健康对照组C组。应用免疫组化法观察A、B两组MMP-9、TIMP-1在肾组织中的表达情况,并且进行半定量分析,比较它们之间有无差别。应用ELISA双抗体夹心法检测A、B、C三组MMP-9、TIMP-1在血清中的浓度,比较它们之间有无差别。观察A、B两组MMP-9、TIMP-1在肾组织中的表达水平与在血清的浓度有无相关性。结果:A、B两组MMP-9在肾小球和肾间质少见表达,主要在肾小管上皮细胞浆中表达增高,两组之间表达的强度有显著差异性;A组TIMP-1在肾小球中少见表达,在肾小管上皮细胞增强。B组TIMP-1在肾小球中有少量表达,在肾小管上皮细胞较A组进一步增强,两组之间表达的强度有显著差异性(P0.05)。血清中MMP-9、TIMP-1浓度在A、B组显著高于C组,血清中MMP-9在A、B两组之间无显著差异性,血清中TIMP-1在A、B、C三组间两两比较有显著差别(P0.05)。结论:慢性肾炎患者血清中MMP-9、TIMP-1浓度与肾脏组织中MMP-9、TIMP-1的表达呈正相关。MMP-9、TIMP-1的相关性分析P值小于0.01。血清MMP-9、TIMP-1参与了肾脏纤维化的进展,慢性肾小球肾炎血清中MMP-9、TIMP-1的浓度可在一定程度上反映肾脏纤维化程度。  相似文献   
629.
目的:针对目前结核性疾病实验室诊断的局限性,探索一种更为敏感和特异的结核分枝杆菌DNA检测新方法。方法:选取10株江苏地区流行的结核分支杆菌(MTB)菌株,选取临床其他常见菌株及分枝杆菌菌株作为对照组,分别提取DNA作为随机引物的模板。参考国内、外文献设计12条随机引物,并分别对MTB及对照菌株进行单个引物随机扩增,2%的琼脂糖凝胶电泳对扩增产物进行分离并切胶纯化,通过TA克隆将纯化片段连接到质粒pEASYTM-T5 Zero并进行测序,通过BLAST-nr比对验证是否为MTB DNA片段。按照所确定的MTB片段序列,在其内部设计、合成一对特异性引物。用此特异性引物扩增对应的随机引物扩增产物,获得MTB特异性条带图谱。并将该方法检测的敏感性和特异性与临床上常用的real-time PCR进行比较。结果:经BLAST-nr比对,随机引物IS986F,S535及IS986R扩增的条带与MTB DNA有高度同源性(均为99%)。随机引物IS986F、S535和IS986R分别联合其特异性引物可以检测稀释105倍、105倍和103倍的MTB DNA,其特异性分别为100%、90%和80%。常规real-time PCR可检测出稀释104倍的MTB DNA。结论:随机引物IS986F联合其特异性引物检测结核分枝杆菌的灵敏度和特异性优于S535、IS986R两组,特异性为100%,且灵敏度优于常规real-time PCR法。  相似文献   
630.
A series of symmetric and asymmetric spermine (SPM) conjugates with all-trans-retinoic acid (ATRA), acitretin (ACI), (E)-3-(trioxsalen-4′-yl)acrylic acid (TRAA) and l-DOPA, amides of ACI, l-DOPA and TRAA with 1-aminobutane, benzylamine, dopamine and 1,12-diaminobutane as well as hybrid conjugates of O,O′-dimethylcaffeic acid (DMCA) with TRAA or N-fumaroyl-indole-3-carboxanilide (FICA) and 2-(2-aminoethoxy)ethanol were synthesized and their antioxidant properties were studied. The reducing activity (RA)% of the compounds were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assay and found to be in the range 0–92(20 min)%/96(60 min)% at 100 μM, the most powerful being the conjugates l-DOPA-SPM-l-DOPA (8, RA = 89%/96%) and l-DOPA-dopamine (13, RA = 92%/92%). Conjugate DMCA-NH(CH2CH2O)2-FICA (14) was the most powerful LOX inhibitor with IC50 33.5 μM, followed by the conjugates ACI-NHCH2Ph (10, IC50 40.5 μM), ACI-SPM-TRAA (7, IC50 41.5 μM), DMCA-NH(CH2CH2O)2-TRAA (15, IC50 65 μM), 13 (IC50 81.5 μM) and ACI-dopamine (11, IC50 87 μM). The most potent inhibitors of lipid peroxidation at 100 μM were the conjugates 15 (98%) and ACI-SPM-ACI (4, 97%) whereas all other compounds showed activities comparable or lower than trolox. The most interesting compounds, namely ATRA-SPM-ATRA (3), 4, 10, 11 and 15, as well as unconjugated compounds such as ATRA and dopamine, were studied for their anti-inflammatory activity in vivo on rat paw oedema induced by Carrageenan and found to exhibit, for doses of 0.01 mmol/mL of conjugates per Kg of rat body weight, weaker anti-inflammatory activities (3.6–40%) than indomethacin (47%) with conjugate 3 being the most potent (40%) in this series of compounds. The cytocompatibility of selected compounds was evaluated by the viability of RAMEC cells in the presence of different concentrations (0.5–50 μM) of the compounds. Conjugates 3 (IC50 2.6 μM) and 4 (IC50 4.7 μM) were more cytotoxic than the corresponding unconjugated retinoids ATRA (IC50 18.3 μM) and ACI (IC50 14.6 μM), whereas conjugate 15 (IC50 12.9 μM) was less cytotoxic than either DCSP (IC50 11.3 μM) or the tert-butyl ester of TRAA (IC50 2.9 μM).  相似文献   
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