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991.
Hui Wu Shuang Zhang Zhigang Wang Jinhao Su Kejiu Du 《Frontiers of Agriculture in China》2010,4(2):226-231
The cis-acting elements of JCesAP, YCesAP, and MDCesAP were analyzed by the PLACE database, the results showed that three
sequences all had a core element and upstream promoter element containing TATA-box and CAAT-box. The sequences related xylem-specific
and wound-defense functions were found in YCesAP and MDCesAP; and the “core xylem gene set” in JCesAP, indicating that three
sequences were xylem-specific and provided with wound-defense functions. Meanwhile, some other elements were also detected,
including some tissue-specific elements and some regulative ones that were induced by light, temperature, and water. For investigating
their functions, three sequences of JCesAP, YCesAP, and MDCesAP were respectively combined with the report gene GFP, and those
reconstructed GFP genes were respectively transferred into the genome of Populus tomentose by Agrobacterium-mediated transformation method. The detected results of GFP expressions in hygromycin B resistant calli of P. tomentosa showed that three sequences all possessed the promoter functions with tissue-specific characteristics. 相似文献
992.
不同裸燕麦品种的淀粉特性 总被引:4,自引:1,他引:3
为给燕麦淀粉的应用以及适宜加工品种的筛选提供依据,从国内主栽燕麦中选取10个品种的11个样品(其中坝莜1号有河北和山西产两种样品)作为供试材料,通过湿法提取燕麦淀粉,并对其组成、黏度及凝胶特性进行了对比分析.结果显示,不同裸燕麦品种的总淀粉含量和直链淀粉含量变幅分别为91.06%~95.98%和21.06%~31.26%,品种间总淀粉变异较小,而直链淀粉变异较大.淀粉糊化特征中,样品间淀粉糊化温度变异最小,平均为82.0℃,反映淀粉糊热稳定性的破损值差异最大(变异系数23.8%).在淀粉的凝胶特性指标中,黏附性差异最为显著(变幅0.00~139.89 g·s),其次为硬度(9.87~43.76 g),弹性、黏聚性差别不显著.11个材料中,坝莜1号(河北产)淀粉糊黏度大.热稳定性好;晋八属于易回生、强凝胶型. 相似文献
993.
994.
995.
It is very essential to extract representative frames in the process of generating video summary. A method is proposed which analyses the color features of the video frames, sets the connectivity threshold values automatically according to the contents, extracts the color coherence vectors (CCV) and then performs adaptive clustering based on equivalent relation. After global partition, local partition was revised with time sequential features. The whole process does not need to set any threshold values. The experiments with diverse videos yields effective results. 相似文献
996.
高职食品安全与检验技术类学习领域课程构建的研究 总被引:2,自引:2,他引:0
"食品质量安全控制与管理"和"食品检测技术"是高职高专院校食品安全与检验技术专业的两个重要学习领域与食品检验和食品生产现场质量安全控制岗位相对接是食品类专业教学改革的关键与难点。在教育部高职高专食品类教学指导委员会的指导下,构建了"食品质量安全控制与管理"和"食品检测技术"两门课程的设置,为规范高职高专院校食品安全与检验技术类专业提供了支撑。 相似文献
997.
马铃薯生料发酵制备乙醇的研究 总被引:1,自引:0,他引:1
比较了商品复合酶和生淀粉酶对马铃薯生料直接发酵转化乙醇的影响,60Co-γ射线辐照处理马铃薯对乙醇发酵的影响。结果表明,以生淀粉酶为糖化剂的发酵液中乙醇体积分数远远高于商品复合酶的乙醇体积分数,辐照处理可显著提高马铃薯生料转化乙醇的能力。 相似文献
998.
Su Q. L. Song H. Q. Lin R. Q. Yuan Z. G. Yang J. F. Zhao G. H. Huang W. Y. Zhu Xing Quan 《Tropical animal health and production》2010,42(8):1805-1808
“Candidatus Mycoplasma haemobos” is a hemoplasma species found in cattle and has been recently reported in Switzerland and Japan. In
this study, “Candidatus Mycoplasma haemobos” was shown to occur in cattle and buffalo in tropical China by PCR amplification and sequence analysis
of the 16S rRNA gene from blood samples. Based on the 16S rDNA sequence, a specific PCR assay was developed. Occurrence of
“Candidatus Mycoplasma haemobos” in cattle and buffalo in Guangxi, China, was determined by examining 25 buffalo blood samples, 12 yellow
cattle blood samples and 42 dairy cow blood samples. The results showed that 32% (8/25) of buffalo, 41.7% (5/12) of yellow
cattle, and 14.3% (6/42) of dairy cows were positive for “Candidatus Mycoplasma haemobos”, respectively. Direct sequencing of representative PCR products confirmed that the amplified partial
16S rDNA sequence represented “Candidatus Mycoplasma haemobos”. This is the first report of “Candidatus Mycoplasma haemobos” in buffalo, yellow cattle, and dairy cows in China. 相似文献
999.
Essential regulation of CNS angiogenesis by the orphan G protein-coupled receptor GPR124 总被引:1,自引:0,他引:1
Kuhnert F Mancuso MR Shamloo A Wang HT Choksi V Florek M Su H Fruttiger M Young WL Heilshorn SC Kuo CJ 《Science (New York, N.Y.)》2010,330(6006):985-989
The orphan G protein-coupled receptor (GPCR) GPR124/tumor endothelial marker 5 is highly expressed in central nervous system (CNS) endothelium. Here, we show that complete null or endothelial-specific GPR124 deletion resulted in embryonic lethality from CNS-specific angiogenesis arrest in forebrain and neural tube. Conversely, GPR124 overexpression throughout all adult vascular beds produced CNS-specific hyperproliferative vascular malformations. In vivo, GPR124 functioned cell-autonomously in endothelium to regulate sprouting, migration, and developmental expression of the blood-brain barrier marker Glut1, whereas in vitro, GPR124 mediated Cdc42-dependent directional migration to forebrain-derived, vascular endothelial growth factor-independent cues. Our results demonstrate CNS-specific angiogenesis regulation by an endothelial receptor and illuminate functions of the poorly understood adhesion GPCR subfamily. Further, the functional tropism of GPR124 marks this receptor as a therapeutic target for CNS-related vascular pathologies. 相似文献
1000.
用2个试验来评估母猪饲料中追加脂肪酸对母猪子宫脂肪酸构成的影响。在试验1中,组1为对照组(基础日粮),组2为亚麻组(基础日粮添加3.75%的亚麻),组3为保护性脂肪酸组(PFA)含有n-3多不饱和脂肪酸(PUFA)。当母猪170日龄时,对其进行配种使其怀孕。在妊娠40~43d将组1的7头、组2的5头和组3的8头妊娠母猪屠宰。结果表明,相比对照组,组2有增加胎儿二十碳五烯酸(EPA:C20:5n-3)的趋势(P=0.055);组3中胎儿的二十二碳六烯酸(DHA:C22:6n-3)含量显著增加;组2和组3中胎儿的绒毛尿囊膜中的DHA含量有显著增加趋势;在组2中的母猪子宫内膜中,EPA和二十二碳五烯酸(DPA)含量和对照组差异显著(P0.001;P0.05),组3的DHA含量也显著增加(P0.001)。总体来看,亚麻组(组2)和保护脂肪酸组(组3)都选择性地使得母猪子宫内膜和绒毛尿囊膜中的EPA和DHA含量有所增加。在试验2中,将含有PFA(1.5%)的170日龄的母猪日粮作为试验组(n=13/每组)日粮,对照组日粮为玉米-豆粕型。30d后采集其血液样本,当母猪205日龄时对其进行人工配种。妊娠11~19d采集其胎儿和母体子宫样本。血液样本数据显示,PFA日粮组的血浆中EPA和DHA含量都有所增加,且试验组的子宫内膜的EPA含量和对照组差异显著(P0.005);另外试验组胚胎外其他组织的EPA和DHA含量也成倍增加;PFA日粮组的19d胎儿的DHA含量较对照组也有所增加(P0.05)。 相似文献