水环境毒物污染点源的生态风险管理现状与展望

评述了发达国家和我国在这一领域的进展和前景。目前国内外常用的基于水质标准／废水排放标准的特征化学污染物法,并不能有效控制组分复杂的废水中的有机毒物排放。因此,仅应用这一传统方法对水环境有机毒物污染点源难以实现有效的生态风险管理。同时采用全废水的生态毒性法可就弥补这一缺陷,根据生态风险管理要求可有效控制组份复杂的废水中有毒有机污染物的排放。鉴别出导致废水生态毒性的关键有机毒物的毒性鉴别评价,是毒物污染点源的生态风险管理核心。本文还对毒性鉴别评价方法学的发展以及全废水毒性法应用于我国水环境毒物污染点源生态风险管理的前景作了评述。     

Compensatory growth responses of seedlings of Pharbitis purpurea (Convulvulaceae) to tissue removal at different seeding depths of seeds

Tissue damage to seedlings can limit their later growth, and the further effects may be greater with increasing seedling age. Seedlings, however, can minimize the effect of damage through compensatory growth. Seedlings of Pharbitis purpurea grow in frequently disturbed habitats and generally tolerate damage to leaf tissues. We evaluated the compensatory responses of the cotyledon to different levels of defoliation and their effect on seedling growth and development. We also examined the relationship between seeding depth and compensatory growth. We tested seven defoliation treatments with one or both cotyledons and/or the apical meristem of seedlings removed from seeds buried at a seeding depth of either 2 or 5?cm. We then measured 12 growth traits of the seedlings to assess development and growth compensation. The area, thickness, biomass, and longevity of the remaining cotyledon were also measured to quantify increased growth as result of treatment effects at both seeding depths. The results showed that defoliation reduced seedling height, belowground length, and total biomass significantly in subsequent growth in all treatments. However, defoliation treatments had direct positive impacts on growth at 2?cm depth compared with 5?cm depth. In contrast, the compensation of cotyledon area (C _area), biomass (C _mass), and thickness (C _thickness) was greater at 5?cm depth than at 2?cm depth. The results thus indicate that P. purpurea seedlings adopted a compensatory growth strategy to resist leaf loss and minimize any adverse effects using the remaining cotyledon. Increasing seeding depth can aggravate the compensatory growth of remain cotyledon after partial defoliation.     

ATG12对缺氧缺血性脑病小鼠神经细胞凋亡和自噬的影响

目的探讨自噬相关蛋白12 （ATG12）对缺氧缺血性脑病（HIE）小鼠细胞凋亡和自噬的影响及分子机制。 方法通过尾静脉注射腺相关病毒构建ATG12低表达小鼠模型,将40只小鼠分为假手术组、HIE模型组、对照病毒模型（NC-HIE）组和ATG低表达病毒模型（ATG12 shRNA-HIE）组,HIE模型组小鼠左侧颈动脉结扎后低氧（8﹪氧气+92﹪氮气）处理2.5?h,假手术组不予结扎和低氧处理。缺氧处理后,荧光定量PCR检测脑组织ATG12 mRNA表达水平。比色法检测各组小鼠大脑神经细胞SOD和MDA水平;通过Tunel法检测各组小鼠大脑神经细胞凋亡水平;通过Western Blot检测各组小鼠大脑神经细胞LC3A/B、ATG12和SQSTM1/?p62蛋白表达水平。采用t检验和单因素方差分析对实验数据进行统计分析。 结果与假手术组小鼠脑组织ATG12 mRNA水平（1.00±0.14）相比,HIE模型组小鼠脑组织ATG12 mRNA水平（5.23±0.37）显著升高（t?= 33.60,P?< 0.01）;与假手术组小鼠脑组织超氧化物歧化酶（SOD）活性[（103.60±4.84）?U/?mgprot]和丙二醛（MDA）含量[（42.40±3.17）?μmol/?mgprot]比较,HIE模型组小鼠脑组织SOD活性[（62.60±3.44）?U/?mgprot]显著降低,MDA含量[（83.80±4.39）?μmol/?mgprot]显著升高,与NC-HIE组小鼠脑组织SOD活性[（61.20±4.39）?U/mgprot]和MDA含量[（85.20± 2.70）?μmol/?mgprot]比较,ATG12 shRNA-?HIE组小鼠脑组织SOD活性[（93.80± 5.43）?U/?mgprot]显著升高,MDA含量[（49.20±3.49）?μmol/mgprot]显著降低,差异具有统计学意义（F?= 222.7,P?< 0.01;F?=?415.8,P?相似文献   

3个鸡种GARS-AIRS-GART基因第21号外显子的SNPs检测

采用PCR-SSCP和DNA测序法对安卡鸡、文昌鸡和如皋鸡中GARS-AIRS-GART基因的第21号外显子进行SNPs检测.结果发现该外显子含4个核苷酸多态位点:G29943A、C29968T、T30011C和C30017T,其中3处为非同义突变,分别为:29 943处天冬氨酸(Asp)→天冬酰胺(Asn)、30 011处色氨酸(Trp)→精氨酸(Arg)、30 017处精氨酸(Arg)→半胱氨酸(Cys);另一处为同义突变.对多态位点进行单倍型分析,发现12种单倍型,其中两种单倍型(5号和6号)的频率超过10%,分别为0.330 0和0.162 8,1号、3号、9号和10号单倍型频率介于1%～10%之间,其余都小于1%.另外共检测到11种基因型,存在5种等位基因,安卡鸡的D和E等位基因的基因频率较高,基因型与其它两个鸡品种之间都存在着极显著的差异(P<0.01),表明我国地方鸡种和外来鸡种在遗传组成上存在着差异.本研究将为鸡肉品质相关研究积累基础数据,为今后深入开展肉品质的开发利用奠定理论基础.     

Cloning, characterization and widespread expression analysis of testicular piRNA-like chicken RNAs

Piwi-interacting RNAs (piRNAs) are small RNAs abundant in the germline that have been implicated in germline development and maintenance of genomic integrity across several animal species including human, mouse, rat, zebrafish and drosophila. Tens of thousands of piRNAs have been discovered, yet abundant piRNAs have still not been detected in various eukaryotic organisms. This is a report on the characterization, cloning and expression profiling of piRNA-like chicken RNAs. Here, we identified 19 piRNAs, each 23–39 nucleotides long, from chicken testis using a small RNA cDNA library and T-A cloning methods. Three different pilRNAs were selected according to size, homology and secondary structure for temporal and spatial expression by Q-PCR technology in different tissues at five growth and four development stages of Chinese indigenous Rugao chickens (RG) and introduced recessive white feather chickens (RW). We found that, consistent to other organisms, pilRNA-encoding sequences within the chicken genome were asymmetrically distributed on the chromosomes while displaying a preference for intergenic regions across the genome. Interestingly, unlike miRNAs with unique stem-loop structures (mature miRNAs form stem section and the rest form loop section), distinct secondary structures of pilRNAs were predicted. In addition, chicken pilRNAs were not only abundant in the germline but also existed in somatic tissues, where, expression levels were influenced mainly by different pilRNAs, breed and gender. Taken together, our results suggest that two distinct secondary structures exist between pilRNAs and miRNAs, which may clarify the splicing and processing mechanisms of the two small RNAs are possible different. Moreover, our results suggest that pilRNAs may not only be confined to development and maintenance of the germline but may also play important roles in somatic tissues. Additionally, different pilRNAs may be involved in the unique regulatory machinery of complex biological processes.     

新疆野生郁金香与栽培品种的杂交性状

为研制具有自主知识产权的郁金香（Tulipa gesneriana）新种质,本实验选择6种栽培郁金香品种为母本,5种野生郁金香为父本进行杂交试验。结果显示,平均受精率为（84．8±3．5）％,母本受精率最高的是克斯奈丽斯,平均为（94．0±2．3）％,受精率最低的是蒙特卡罗,平均为（71．0±3．8）％。果实发育1个月最高坐果率为100．0％,平均为（75．2±4．1）％,2个月最高坐果率为（90．0±3．6）％,平均为（47．0±3．4）％;杂交种子平均结实率为24．3％。研究结果表明,母本与杂交组合对受精率、坐果率和结实率有显著影响,父本则没有显著影响：杂交组合小黑人×伊犁郁金香、小黑人×柔毛郁金香及小黑人X天山郁金香亲合性较好,其杂交种子结实率分别为78．2％、68．4％和57．5％。     

Proprioceptive neuromuscular facilitation increases alpha absolute power in the dorsolateral prefrontal cortex and superior parietal cortex

The physiotherapist’s clinical practice includes proprioceptive neuromuscular facilitation (PNF), which is a treatment concept that accelerates the response of neuromuscular mechanisms through spiral and diagonal movements. The adaptations that occur in the nervous system following PNF are still poorly described in the literature. Thus, this study had a goal to investigate the electrophysiological changes in the fronto-parietal circuit during PNF and movement in sagittal and diagonal patterns. This study included 30 female participants, who were divided into three groups (control, PNF, and flexion groups). Electroencephalogram measurements were determined before and after tasks were performed by each group. For the statistical analysis, a two-way ANOVA was performed for the factors group and time. Interactions between the two factors were investigated using a one-way ANOVA. A value of p?相似文献