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51.
Chino H Sakurai S Ohtaki T Ikekawa N Miyazaki H Ishibashi M Abuki H 《Science (New York, N.Y.)》1974,183(4124):529-530
An in vitro study in which isolated prothoracic glands of the Bombyx silkworm were cultured has provided definite evidence that the prothoracic gland is the site where molting hormone is synthesized. The hormone behaved very similarly to free ecdysone on thin-layer chromatography. Analysis by liquid chromatography and mass fragmentography revealed that the hormone is identical with alpha-ecdysone. 相似文献
52.
[目的]了解长龄壮秧对超稀植杂交稻生长和产量的影响。[方法]设T1(30d)、T2(42d)T3(54d)3个秧龄处理,研究B优827、岗优725和D优527超稀植时的生长及产量情况。[结果]随着秧龄的延长,3个品种的最高分蘖期推迟。同一品种不同处理的单株最大茎蘖数无明显差异。岗优725的平均单株有效穗数为T1>T2>T3,其余两品种的为T2>T1>T3。3个品种T3处理的二次分蘖穗占总有效穗的比例下降,三次分蘖穗的比例增加。B优827和D优527的实收产量为T1>T2>T3,岗优725的为T2>T1>T3。不同品种对秧龄长短的反应有明显差异。[结论]秧龄对超稀植杂交稻的分蘖动态、有效穗及其组成、经济性状和产量都有一定的影响。在良好管理的基础上,合理选用品种,长龄壮秧超稀植杂交稻仍能保持高产水平。 相似文献
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55.
Dongyan Qu Zhangping Yang Xiaoya Guo Yongjiang Mao Wei Sun Rongqing Gen Xianglian Ren Guobing Chang Danli Huang Hong Chang Yuehui Ma 《Frontiers of Agriculture in China》2007,1(4):472-477
The genomes of six populations were screened using microsatellites as molecular markers, including Ujmuqin sheep, small-tailed
Han sheep, Tan sheep, Hu sheep, Tong sheep and Yangtse River Delta (YRD) white goat. A total of seven microsatellite markers
were used and genetic diversity and genetic distance were also determined. The results showed that there were 224 alleles
in six populations, all seven loci showed polymorphism in all populations. The average heterozygosity of all populations was
0.949 9, and the mean polymorphism information content (PIC) of all six populations was 0.842 5–0.929 4. The six sheep (goat) popualtions were lowly differentiated with all loci, and
the coefficient of phaenotype differentiation (Fst) was 2.6%, which was consistent with the coefficient of gene differentiation (Gst). The global heterozygote deficit across of all populations (Fit) amounted to 0.5%. The overall significant deficit of heterozygotes because of inbreeding within breeds (Fis) amounted to −2.2%. Two Unweighted Pair-group Method using Arithmetic Averages (UPGMA) dendrograms were constructed on the
basis of Nei’s standard genetic distance (DS) and Nei’s genetic distance (DA) respectively. Hu sheep and Tong sheep were grouped
at first, Ujmuqin sheep and small-tailed Han sheep clustered and then clustered with Tan sheep. Finally, Yangtse River Delta
white goat joined in with all above. From this study, Ujmuqin sheep belongs to “Mongolia sheep” group, which corresponds with
the historical records exactly. Ujmuqin sheep and small-tailed Han sheep, Tan sheep, Hu sheep and Tong sheep all vest in the
“Mongolia sheep” group. 相似文献
56.
指出了校风建设的意义和原则,提出了建设良好的学生学风、教师教风和工作作风的要求、途径和方法。 相似文献
57.
从利用藻类净化含氮、磷有机污水其净化作用及其机理、藻类培养环境调控及其生物量利用和新型藻类处理系统三方面介绍了国内外的有关研究现状及其发展趋势。 相似文献
58.
Sakurai Y Itou M Barbiellini B Mijnarends PE Markiewicz RS Kaprzyk S Gillet JM Wakimoto S Fujita M Basak S Wang YJ Al-Sawai W Lin H Bansil A Yamada K 《Science (New York, N.Y.)》2011,332(6030):698-702
The high-temperature superconducting cuprate La(2-x)Sr(x)CuO(4) (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2p(x)/p(y) orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials. 相似文献
59.
多年来因试种农作物新品种方法不当而遭受较大损失的现象屡见不鲜。近年来关于新品种试种而造成较大损失的“新闻”也不绝于耳.鉴于试种上的教训,农民朋友在接受农作物品种试种时要谨防以下误区. 相似文献
60.
Preparation of phytate-removed deamidated soybean globulins by ion exchangers and characterization of their calcium-binding ability. 总被引:3,自引:0,他引:3
Hitomi Kumagai Shigeo Ishida Atsushi Koizumi Hidetoshi Sakurai Hitoshi Kumagai 《Journal of agricultural and food chemistry》2002,50(1):172-176
Phytate-removed deamidated soybean globulins were prepared using ion-exchange resins to provide them with a functional property to enhance calcium absorption in the body. The phosphorus level was reduced from 45 to 20 micromol/g using 0.05 g/mL of AE-4, an anion-exchange resin with a (2-hydroxyethyl)dimethylammonium group, in 0.2% soybean globulin solution for 1 h at 4 degrees C, and 90-92% of the phosphorus in defatted soybeans could be removed. As for deamidation, CE-4, a cation-exchange resin of the carboxylate type, showed a much higher deamidation activity than CE-1 and CE-2, cation-exchange resins of the sulfonate type. No peptide bond hydrolysis was observed for any cation-exchange resin treated at 4 degrees C. There was no significant difference in the amount of acid amide deamidated at temperatures between 4 and 50 degrees C. The deamidation level was able to increase to 73% using 0.10 g/mL of CE-4 in a 0.2% soybean globulin solution for 6 h at 4 degrees C. The amount of calcium bound to the soybean globulins decreased with removal of the phytate but increased with deamidation. 相似文献