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931.
By using RACE (rapid amplification ofcDNA ends) based homologous cloning strategy, we have successfully isolated the genomic and full-length cDNA sequences of a gene encoding typical DFR (dihydroflavonol-4-reductase) from black-seeded Brassica campestris L. var. oleifera DC.. The gene, designated BcDFR here, is 1 722bp in length and harbors 5 introns with typical splice sites of plant DFR genes. BcDFR cDNA is 1311bp in length with a 1 158bp ORF as well as a 25bp 5‘ UTR and a 128bp 3‘ UTR. The encoded BcDFR protein is 385 aa with a calculated Mw of 42.85kD and a pI value of 5.55. The nucleotide and amino acid sequences of this gene share extensive homologies to plant DFR genes of wide origins especially high similarities to Cruciferous DFR genes. Sequence analyses such as phylogenetic analysis, conserved domain search and substrate specificity region detection all indicated that BcDFR gene is a quite potentially biofunctional gene. Its cloning enables us to further dissect the possible relatedness between DFR gene and Brassica seed coat color traits and to create transgenic novel yellow-seeded rapeseed germplasm through antisense- or RNAi-suppression of DFR gene expression in black-seeded elite cultivars. 相似文献
932.
果蔬产品变色原因分析及其控制 总被引:4,自引:0,他引:4
分析了果蔬产品在加工贮存中变色的原因,综述了目前生产中常用的行之有效的护色措施,包括生物、化学和物理等方面的处理方法。 相似文献
933.
934.
Discussion of the Application and Foreground of Falling Water Aeration with the Process of Sewage Treatment 下载免费PDF全文
The engineering design of sewage treatment plant for the Chongqing city, P. R. China is analyzed in this paper. Considering the situation of China and other projects, the characteristics of falling water reactor for the environment protection project and economy of investment is introduced ; the application and foreground of falling water aeration in the process of sewage treatment is discussed, such as Oxidation - ditch, SBR, and so on. The conclusion indicated that the falling water aeration can be designed and used as an independent aeration, and, it is an upgraded technology of sewage treatment which is adaptive for city water environment control in middle and small towns in China. The falling water aeration may reduce running cost of the sewage treatment plant, is adaptive for foothill and the mountainous areas, and reduces project investment and environments damage. 相似文献
935.
不同花生品种侧枝发育动态与产量性状研究 总被引:1,自引:0,他引:1
花生一级侧枝发育具有不均衡性。第一、二对侧枝出现早,伸长快,其他一级侧枝出现晚,伸长慢。86036-26-1第一、二对侧枝发育相对较早,而其他一级侧枝发育较晚;海花1号和豫花1号第一、二对发育相对较晚,而其他一级发育较快;豫花7号和鲁花9号居中。海花1号一级侧枝及第一对侧枝的二级侧枝数最多,86036-26-1的一级侧枝数及第一对侧枝的二级侧枝数量少。在花针期之前第一对侧枝的伸长与主茎基本同步;花针期之后,第一对侧枝伸长速度超过主茎。86036-26-1的一级侧枝长及株高居首位。86036-26-1第一、二对侧枝饱果率,产量居第一,豫花7号居第二。海花1号虽然荚果数较多,但第一、二对侧枝孢果率较低,产量也较低;鲁花9号居中。 相似文献
936.
937.
938.
Xie Ming Guo Xiaoyu Wang Yanchun 《保鲜与加工》1993,(6):134-137
A minimum ring-band mathematical definition :In the done ring-band, there are at least two inner points and two outer points which scatter staggeringly on the circumference. With this definition as the rule of searching calculation' s ending,a fast numerical algorithm of gaining the minimum ring-band of a closed curve was suggested:Make a ring-band with the four points scattered staggeringly,then replace the old points with new ones continuously until all the points are located within the ring-band. The method was used in an application example to measure the spindle rotating precision of machine tools. 相似文献
939.
《Journal of Cereal Science》2014,59(3):451-456
Brans of 23 traditional and 12 improved (both red and white) rice varieties in Sri Lanka were screened for anti-amylase and anti-glycation activities in vitro. Varieties which showed the highest inhibitory activities at screening were further investigated for anti-glucosidase and glycation reversing as anti-diabetic properties. The same varieties were studied for selected antioxidant properties. Significantly high anti-amylase and anti-glycation activities were observed for bran extracts of red varieties compared to white varieties at screening. Traditional red rice varieties, Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti, exhibited significant and dose dependent anti-amylase, anti-glycation and glycation reversing activities. These varieties also showed marked antioxidant properties. It is concluded that brans of Sri Lankan traditional red rice varieties Masuran, Sudu Heeneti, Dik Wee and Goda Heeneti may be potential food supplements for diabetes. 相似文献
940.
Research on Relationship between the Level of Urbanization and the Growth of Real Estate Investment 下载免费PDF全文
The population proportion index is usually introduced to measure the level of urbanization, which is an important index to the national economy. The fast development of urbanization would inevitably cause the increase of the investment in real estate industry. Introducing the Granger Test of Causality analytical method, in this paper the relationship between the level of urbanization and the investment in real estate industry from 1986 to 2003 in China is analyzed. It reveals that both of them are on the stage of constant up - rising, and the correlation index of 0. 205 shows that the relationship between them is a mutual promoting causality. 相似文献