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91.
王浩 《农业图书情报学刊》2014,26(12)
以黑龙江八一农垦大学图书馆读书沙龙为例,对读书沙龙的主题选择、现场组织和宣传报道等进行总结分析,阐述读书沙龙为大学文化建设带来的影响,并对办好读书沙龙活动提供了一些新的思路. 相似文献
92.
绿色木霉Fn10-1纤维素酶的分离纯化及酶学特性测定 总被引:1,自引:0,他引:1
试验研究了绿色木霉Fn10-1纤维素酶的初步纯化及酶学性质开展研究。结果表明,该纤维素酶的最适催化温度为70℃,最适pH 7.6,在温度为4~50℃下均能保持较稳定的酶活,高于50℃以后,热稳定性变差,酶活力开始急剧下降。pH在5.6~7.6时该酶有较好的稳定性。Na+、Mn2+、Fe2+、Mg2+、Co2+、Ca2+、Ba2+、Al3+对纤维素酶具有一定的激活作用,Ag+、Fe3+、Cu2+、Zn2+、K+对该酶有一定的抑制作用,其中Cu2+的抑制作用尤为明显。 相似文献
93.
刘皓 《农产品加工.学刊》2014,(15):53-54,56
用含有5种不同质量分数PEG-6000的1/2 Hoagland溶液模拟干旱胁迫,研究杠柳种子萌发期的过氧化物酶(POD)活性和丙二醛(MDA)含量的变化。结果表明,随着干旱胁迫程度的增加,POD活性整体呈现增长趋势,说明低质量分数PEG能够刺激诱导自由基清除系统中POD活性的增加;MDA含量随PEG质量分数的升高而增长,说明干旱胁迫程度增加使种子内活性氧的量增加,膜质过氧化程度随之增加,产物MDA含量升高;在PEG质量分数为25%时,POD活性降低,MDA含量明显增加,说明干旱胁迫增加到一定程度时,POD活性会受到抑制,活性氧的量增加,膜的受损程度增加。 相似文献
94.
Characterization of Genomic Integration and Transgene Organization in Six Transgenic Rapeseed Events
To characterize the DNA rearrangement of both the T-DNA region and the genomic insertion site during T-DNA insertion, the Genomewalker strategy was used to isolate the junctions between the inserted DNA and the plant genomic DNA in six rapeseed events as well as the genomic DNA at the sites before integration. During transformation in each of the six events, portions of both the right border(RB) and left border(LB) regions of the T-DNA were deleted, ranging from a 7 nucleotide deletion of the LB repeats in event RF1 to a 207 bp deletion of the LB region in event RF2. For the six events, T-DNA integration resulted in a deletion at the target site spanning less than 100 bp. Sequence analysis indicated that the T-DNA was integrated into the coding region of various native rapeseed genes in events RF1 and RF2. Duplications of the genomic DNA target site were observed in events RF2, RF3 and Topas 19/2. And multimerization of transgenes was found in event Topas 19/2, in which, the T-DNA was integrated as a head-to-head(RB-to-RB) concatemer into the recipient genome. In event MS1, chromosomal translocation or a large target-site deletion may have occurred during T-DNA integration, which was identified due to a failure to amplify the presumptive insertion site based on the flanking rapeseed DNA sequences. Our results provide comprehensive data concerning transgene organization and the genomic context of the T-DNA in six rapeseed events, which can aid in the developing of insert fingerprinting and the monitoring of long-term genetic stability and potential unintended effects of transgenic events. 相似文献
95.
马铃薯脱毒快繁技术繁殖倍数高,周期短,短时间内就可获得大批量马铃薯试管苗,但是脱毒快繁的成本比较高。如果在快繁的同时,保证质量的前提下,能节约成本,那对于马铃薯试管苗的工厂化生产是很有利的,也能大幅度提高其经济效益。 相似文献
96.
内蒙古膜下滴灌棉花叶面肥施用效果 总被引:1,自引:0,他引:1
以中棉所50和天元1号为材料,以喷施清水为对照,通过田间试验研究了从蕾期到铃期6次叶面喷施1%(质量分数,下同)尿素、0.5%磷酸二氢钾、1%尿素+0.5%磷酸二氢钾3种叶面肥对内蒙古膜下滴灌棉花产量与品质的影响。结果表明,喷施叶面肥处理均比对照增产,皮棉增产幅度为6.0%~10.6%,喷施1%尿素+0.5%磷酸二氢钾处理增产效果最佳。叶面肥处理对棉花纤维品质无显著影响,施用1%尿素+0.5%磷酸二氢钾叶面肥处理棉花纤维上半部平均长度、断裂比强度优于对照。 相似文献
97.
ZHONG Xing-fu WANG Pei-kun YANG Yong-li QIN Li-li BI Yu-yu ZOU Guang-zhen PENG Hao WEI Ping 《中国畜牧兽医》2015,42(7):1647-1653
In order to investigate the infection status of avian leukosis virus (ALV) and avian reticuloendotheliosis virus (REV) in the major local breeds of Qinzhou,Guangxi,totally 953 samples of egg white,cloaca swab and serum of Ma duck,Shitou goose,Tiejiao-Ma chicken,turkey and pigeon were collected from the representing flocks and detected by the commercial ELISA kits.ALV was isolated for the ALV p27 positive samples by culturing on DF-1 cells,and gp85 gene was sequenced.The results showed that the detections of ALV were negative in the samples except those of Tiejiao-Ma chicken,while REV antibody was found positive in Ma duck,Tiejiao-Ma chicken and turkey.The nucleotide sequences of gp85 gene of two isolates shared 94.5% identity with each other,and shared 86.9% to 94.9% with reference strains.The amino acid sequences of gp85 gene of two isolates shared 91.5% identity with each other,and shared 84.0% to 91.6% with reference strains.There were many variable sites in the hyper variable region hr1 and hr2,and the vr2 and vr3 variable regions were relatively conservative.Phylogenetic tree analysis showed that the two isolates shared the highest homology with SCAU11-XG strain. 相似文献
98.
GUAN Yu-yu LIAO Rong-rong WANG Zhen ZHAO Jing CHEN Zhen-liang ZHANG Zhe XIAO Qian SUN Hao WANG Qi-shan ZHANG Xiang-zhe YANG Chang-suo PAN Yu-chun 《中国畜牧兽医》2016,43(6):1413-1421
The study was conducted to explore the potential different characters between Blue-shelled chicken and White leghorn.Global genome microRNA was combined the identified microRNA with complementary lab-predicted microRNA.Then the two breed chicken's SNP data got by GGRS were mapped to the microRNA and focused on SNP that deliberately located in mature-microRNA.Bioinformatics method was adopted for target prediction on microRNA which had SNPs.By further gene enrichment analysis,the study found these genes enriched in 22 GO terms,10 KEGG pathways,and 3 IPA important networks.And they enriched in traits which associated with growth,such as mTOR signaling pathways,Wnt signaling pathways,growth hormone receptor networks and insulin-like growth factor Ⅰ receptor networks.And they also enriched in some laying traits,such as oocyte meiotic signaling pathways and progesterone mature oocytes signaling pathways.The methods and the results might provide references for further studies. 相似文献
99.
LIU Ying-yu WANG Jin-quan WUMAIERJIANG Yahefu LIU Li-li LI Lin ZHANG Xiao-hong YAO Gang 《中国畜牧兽医》2016,43(4):985-990
In order to understand the situation of heavy metal residues of the beef industry chain in Yili area of Xinjiang.The heavy metals (Pb, As, Hg, Cr and Cd) in soil, feed and beef of the cattle farm were determined using the atomic absorption spectrometry.The results showed that the heavy metal (Pb, As, Hg, Cr and Cd)contents in soil samples were 0.03-0.20, 3.87-8.30, 0.15-0.23, 0.09-0.48 and 0.41-0.86 mg/kg, respectively.The heavy metal (Pb, As, Hg, Cr and Cd) contents in feed samples were 3.01-18.09, 75.35-94.27, 19.65-24.37, 0.06-1.04 and 1.81-8.46 μg/kg, respectively.The heavy metal (Pb, As, Hg, Cr and Cd) contents in beef samples were 0.23-0.54, 1.22-7.12, 0.28-0.53, 0.01-0.27 and 0.02-0.03 μg/kg, respectively.The correlation coefficient of the heavy metal element between soil and feed, feed and beef, soil and beef were 0.96, 0.99 and 0.98, respectively.It was concluded that the heavy metal (Pb, As, Hg, Cr and Cd) contents in soil, feed and beef of the cattle farms in Yili area did not exceed the standard and that in the soil, feed and beef had the high correlations. 相似文献
100.