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1.
Blast菠萝果实不同发育时期的cDNA文库测序结果,并用信息生物学软件和相关网站进行拼接和分析,设计特异引物RT-PCR.得到一个2750bp、编码761个氨基酸的全长基因序列,命名NRFD1。预测该蛋白是一个亲水性、且具有多个磷酸化位点的分泌性蛋白,可能位于叶绿体中。半定量PCR分析发现RFD1基因表达量在果实发育期不断增加,70d达到最高:而在70d果实的不同部位并没有显著差异性,仅果实外部略有增高。  相似文献   
2.
棕色棉与白色棉缩合单宁单体儿茶素动态变化的比较   总被引:2,自引:0,他引:2  
以棕色棉ANL-1’和白色棉‘泗棉3号’为材料,利用HPLc检测棉纤维发育过程中儿茶素的动态变化,结果表明:棉种皮中的儿茶素含量高于棉纤维中的,各种儿茶素单体(EGC、C、EC、EGCG、GCG、ECG、cG)的含量在花后30d迅速下降,其中在白色棉纤维中的下降幅度最大;棕色棉和白色棉发育期棉纤维中儿茶素存在很大差异,如棕色棉纤维中有Ec、CG,但在白色棉纤维中却没有发现。初步推断棕色棉与白色棉纤维中缩合单宁结构有较大不同,可能导致棉纤维颜色发生差异。  相似文献   
3.
三种接种物启动Anammox-EGSB反应器的性能   总被引:2,自引:0,他引:2  
为了优选接种物和加速Anammox反应器启动,分别以厌氧产甲烷污泥 (Anaerobic methanogenic sludge,AMS)、新鲜厌氧氨氧化污泥 (Fresh Anammox sludge,FAS) 和储藏厌氧氨氧化污泥 (Stored Anammox sludge,SAS) 作为接种物,研究了厌氧氨氧化膨胀颗粒污泥床 (Anammox-EGSB) 反应器 (R1、R2和R3) 的启动性能。结果表明:3种接种物均能成功启动Anammox-EGSB反应器,启动性能的优劣次序为:R2 (接种物为  相似文献   
4.
Breeding strategies of Acrossocheilus fasciatus were studied from 592 specimens collected monthly during May 2007 and April 2008 in the Puxi Stream of the Huangshan Mountain.Sex ratio of the studied population was 0.90∶1(♀∶♂),not significantly different from 1∶1.Both sexes reached their first sexual maturity at age 2(the second calendar year of their birth).Fifty percent of females and males reached maturity at a total length of 69.75 mm and 69.36 mm respectively,and the minimum total length was 61.54 mm an...  相似文献   
5.
Next-generation sequencing (NGS) technologies have been widely used in life sciences. However, several kinds of sequencing artifacts, including low-quality reads and contaminating reads, were found to be quite common in raw sequencing data, which compromise downstream analysis. Therefore, quality control (QC) is essential for raw NGS data. However, although a few NGS data quality control tools are publicly available, there are two limitations: First, the processing speed could not cope with the rapid increase of large data volume. Second, with respect to removing the contaminating reads, none of them could identify contaminating sources de novo, and they rely heavily on prior information of the contaminating species, which is usually not available in advance. Here we report QC-Chain, a fast, accurate and holistic NGS data quality-control method. The tool synergeticly comprised of user-friendly tools for (1) quality assessment and trimming of raw reads using Parallel-QC, a fast read processing tool; (2) identification, quantification and filtration of unknown contamination to get high-quality clean reads. It was optimized based on parallel computation, so the processing speed is significantly higher than other QC methods. Experiments on simulated and real NGS data have shown that reads with low sequencing quality could be identified and filtered. Possible contaminating sources could be identified and quantified de novo, accurately and quickly. Comparison between raw reads and processed reads also showed that subsequent analyses (genome assembly, gene prediction, gene annotation, etc.) results based on processed reads improved significantly in completeness and accuracy. As regard to processing speed, QC-Chain achieves 7–8 time speed-up based on parallel computation as compared to traditional methods. Therefore, QC-Chain is a fast and useful quality control tool for read quality process and de novo contamination filtration of NGS reads, which could significantly facilitate downstream analysis. QC-Chain is publicly available at: http://www.computationalbioenergy.org/qc-chain.html.  相似文献   
6.
Study of the tolerance of Hippochaete ramosissimum to Cu stress   总被引:1,自引:0,他引:1  
We investigated the tolerance of Hippochaete ramosissimum and the changes in physiological metabolism following exposure to copper using pot experiments and analyzing plant physiology and biochemistry. The results showed that Cu tolerance in Hippochaete ramosissimum varied significantly between different populations; the tolerance of plants living in Cu polluted areas for extended periods of time exceeded that of plants living in unpolluted areas. SOD and POD activities in highly Cu tolerant plants increased noticeably following exposure to Cu. This indicates that maintaining and increasing the two kinds of protective enzyme activities are the primary foundations of plant tolerance. However, no change in CAT activity was demonstrated following Cu exposure. In summary, there existed considerable differences in physiological metabolism between different populations of Hippochaete ramosissimum following exposure to Cu.  相似文献   
7.
高效降解棉酚菌株的选育及脱毒条件的研究   总被引:19,自引:0,他引:19  
From mildewed cottonseed cake and stock cultUres of mold and yeast We select more than ten strains of yeastS and molds which can degrade cotton Phenol. At last we got four strains which can degrade cotton phenol highly effeted after mutagenized by physical and chemical factors and induced by cotton Phenol. They belong to Candida tropicalis, Torulopsis candida, Aspergillus flavus and ASPergillus niger. By small and medium size fermenfations, the content of dissociated cottom Phenol all reach safe criterion (…  相似文献   
8.
水资源的忧虑   总被引:2,自引:2,他引:0  
水是生态系统中生命必需元素得以无限循环的介质。没有水生态系统,生命就不能维持。在当今世界面临的人口、资源、环境三大问题中,水属于人类赖以生存和社会经济发展的重要物质资源,又和其它两个问题有着密切的关系。因此,水资源的开发、利用和管理已成为世界各国普遍重视的一个重要课题。  相似文献   
9.
本文报道在云南省昆明市华山松(Pinus armandi Franch.)上发现的斑痣盘菌科一新种,即松生小鞋孢盘菌(Soleella pinicola Y.R.Lin et W.Ren)。对该种作了拉丁文、汉文描述和图解。主模式标本保藏于安徽农学院林学系森林保护教研室。  相似文献   
10.
汪仁平 《四川动物》1999,18(4):176-178
目前能进行国际贸易的鳄有12 种, 但它们只能被允许在某些国家和不同控制方式下的出口贸易。鳄类的人工饲养在世界上是一种新型产业, 它有二种饲养方式, 但都必须具备种群、食物、资金和技术四个基本要素。饲养技术的关键是对鳄生活习性的了解, 本文对几种鳄的栖息地和繁殖特点作了介绍。  相似文献   
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