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21.
通过分析１９５１年至１９９６年杭州逐年最高、最低气温，逐月、年平均温度，１月最低温度小于０℃日数、７月最高气温大于或等于３５℃日数等资料，研究了杭州４６年来气温的变化趋势，结果表明：杭州年平均气温呈上升趋势，线性增加率为１．０９℃／１００ａ，其中，秋、冬、春三季气温明显上升，１０月平均气温的线性增加率最大，为２．７０℃／１００ａ；夏季气温则呈下降趋势，７月平均气温的线性递减率最大，为－１．０８℃／１００ａ；气温变化总体是非对称的． 相似文献
22.
利用高保真PCR酶从克隆载体pMD18T-GmPHD2中扩增出大豆PHD类转录因子GmPHD2,并于基因上下游分别引入XbaI和XhoI酶切位点;然后通过TA克隆、载体双酶切、连接、转化等技术手段,将其连入植物表达载体pBA002,构建了含GmPHD2和抗除草剂筛选标记Bar基因的植物表达载体pBA002-GmPHD2。重组质粒经PCR检测、双酶切及测序验证,表明GmPHD2基因已被完整、正确的插入到pBA002载体中,之后通过冻融法将重组质粒pBA002-GmPHD2成功导入农杆菌EHA105,利用此农杆菌不仅可以介导转化大豆,而且可以转化非同源的其他作物,为进一步开展植物抗逆性的基因工程研究提供了新基因资源。 相似文献
23.
Shu-na Yuan Malik Waqas Shui-jin Hua Noreen Bibi Xue-de Wang 《Journal of Zhejiang University. Science. B》2012,13(6):478-486
Colored cotton has naturally pigmented fibers. The mechanism of pigmentation in cotton fiber is not well documented. This experiment was conducted to study the effects of respiratory chain inhibitors, i.e., rotenone and thiourea, on pigmentation and fiber development in colored cotton. After 1 d post-anthesis, ovaries were harvested and developing ovules were cultured on the liquid medium containing different concentrations of rotenone and thiourea for 30 d. The results demonstrate that both respiratory inhibitors reduced fiber length and ovule development under ovule culture conditions, and the inhibition efficiency of rotenone was much higher than that of thiourea. Rotenone and thiourea also showed significant effects on fiber pigment (color) development in colored cotton. In green cotton fiber, rotenone advanced fiber pigment development by 7 d at 200 μmol/L, while thiourea inhibited fiber pigmentation at all treatment levels (400, 600, 800, 1 000, and 2 000 μmol/L). Both respiratory inhibitors, however, had no significant effects on pigmentation of brown cotton fibers. The activities of cytochrome c oxidase (COX) and polyphenol oxidase (PPO) decreased significantly with increasing levels of both respiratory inhibitors. It is suggested that both respiratory inhibitors have important roles in deciphering the mechanism of pigmentation and fiber development in colored cotton. 相似文献
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25.
论科技期刊编委责任制的建立与完善 总被引：1，自引：0，他引：1
实施编委责任制对确保科技期刊质量和提高工作效率是行之有效的举措。阐述编委责任制的内容和实施现状,建立和完善编委责任制应明确编委的责任和权利,认为应建立编委责任制考核评价体系、激励和约束机制,同时辅之以建立与编委良好的沟通机制、编委的评审与推荐署名机制等措施。 相似文献
26.
Gu-wen Zhang Sheng-chun Xu Wei-hua Mao Qi-zan Hu Ya-ming Gong 《Journal of Zhejiang University. Science. B》2013,14(4):279-288
The development of expressed sequence tag-derived simple sequence repeats (EST-SSRs) provided a useful tool for investigating plant genetic diversity. In the present study, 22 polymorphic EST-SSRs from grain soybean were identified and used to assess the genetic diversity in 48 vegetable soybean accessions. Among the 22 EST-SSR loci, tri-nucleotides were the most abundant repeats, accounting for 50.00% of the total motifs. GAA was the most common motif among tri-nucleotide repeats, with a frequency of 18.18%. Polymorphic analysis identified a total of 71 alleles, with an average of 3.23 per locus. The polymorphism information content (PIC) values ranged from 0.144 to 0.630, with a mean of 0.386. Observed heterozygosity (H o) values varied from 0.0196 to 1.0000, with an average of 0.6092, while the expected heterozygosity (H e) values ranged from 0.1502 to 0.6840, with a mean value of 0.4616. Principal coordinate analysis and phylogenetic tree analysis indicated that the accessions could be assigned to different groups based to a large extent on their geographic distribution, and most accessions from China were clustered into the same groups. These results suggest that Chinese vegetable soybean accessions have a narrow genetic base. The results of this study indicate that EST-SSRs from grain soybean have high transferability to vegetable soybean, and that these new markers would be helpful in taxonomy, molecular breeding, and comparative mapping studies of vegetable soybean in the future. 相似文献
27.
Hong-gang Tang Li-hong Chen Chao-geng Xiao Tian-xing Wu 《Journal of Zhejiang University. Science. B》2009,10(2):154-158
We investigated the fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age. One- and two-year-old fish were cultured in floating net cages and sampled randomly for analysis. Moisture,
protein, lipid and ash contents were determined by methods of Association of Analytical Chemist (AOAC) International. Fatty
acid profile was determined by gas chromatography. Crude protein, fat, moisture and ash contents showed no significant differences
between the two age groups. The contents of total polyunsaturated fatty acids and docosahexaenoic acid (DHA) were significantly
higher and eicosapentaenoic acid (EPA) content was significantly lower in the two-year-old large yellow croaker than in the
one-year-old (P<0.05). No significant differences were observed in the contents of total saturated fatty acids and monounsaturated fatty
acids, or the ratio of n-3/n-6 fatty acids among the large yellow croakers of the two age groups. We conclude that large yellow croakers are good food
sources of EPA and DHA.
相似文献
28.
论量刑规范中的检察量刑建议权 总被引：1，自引：0，他引：1
检察机关量刑建议权符合法的本质,对规范量刑程序,有效制约人民法院的量刑裁量权,切实加强审判监督有着积极意义。检察机关量刑建议权以对正义、公平的设定为准绳,按法制原则使国家刑罚权的行使与公民的自由权利实现最大限度的融合。 相似文献
29.
《Early childhood research quarterly》2002,17(2):259-277
This study compares how parents in Germany and the USA perceive the quality of ECE services their preschoolers receive in the two different cultures and ECE systems existing in the countries. The sample included 2,407 parents in the USA and 392 in Germany. Classroom quality was assessed by trained observers using the USA and German versions of the Early Childhood Environment Rating Scale (ECERS). Parents’ perceptions of ECE programs were measured with a parent questionnaire (ECERSPQ), which is an adaptation of the ECERS. Findings show that in both countries, parents indicate high importance for the aspects of quality required in the ECERS/ECERSPQ, that parents assign substantially higher quality scores to their children’s classrooms than do trained observers, and parent quality assessments are influenced by the relative importance they attribute to aspects of quality. Findings are discussed in terms of assisting parents to become more discriminating in their child care choices. 相似文献
30.
用１９５３—１９９５年逐年月平均副高因子（脊线、北脊点、西脊点位置）资料,杭州、金华、衢州、温州４站７月份月降水量和月平均温度资料以及浙江省年干旱面积资料,分析并总结出浙江省干旱的副高概念模型,还拟合出用４个代表站７月的月降水量、月平均温度作预报因子,预测浙江省年干旱面积的线性方程,试用结果表明,有一定的参考价值． 相似文献