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N. Pallais S. Villagarcia N. Fong J. Tapia R. Garcia 《American Journal of Potato Research》1987,64(9):483-491
The effect on true potato seed (TPS) weight of supplemental nitrogen (N) applied during seed development was investigated using crosses DTO-33 × R128.6 (“A” produced in the field) and Atzimba × R128.6 (“B” produced in the field and in a screenhouse). Dry weights of tops and tubers of the mother plants were also measured in the screenhouse. The response to supplemental N (0-240 kg/ha) in 100-TPS weight of cross A and B from the field was positive and linear. In the screenhouse, where higher total N (0-1200 kg/ha) was applied, the responses in 100-TPS weight and dry weight of tops and tubers were curvilinear, with maximum levels at 800, 1000 and 400 kg/ha, respectively. The 100-TPS weight of cross B was 40% higher in the field than in the screenhouse. In the field, increased frequency of supplemental N applications increased 100-TPS weight of large and medium berries of cross B, but had no effect on seed from small berries nor on seed from any berries of cross A. In the screenhouse, increased application frequency decreased tuber dry weight and increased dry weight of tops, but had no effect on 100-TPS weight. It was concluded that supplemental N must be applied during seed development and at higher total levels than those required for optimum tuber yields in order to maximize 100-TPS weight. The lower seed weight from the screenhouse suggests that other environmental factors (e.g., temperature) present during growth of the mother plant can affect the weight of the resultant TPS. 相似文献
83.
Activation by IKKalpha of a second, evolutionary conserved, NF-kappa B signaling pathway 总被引:1,自引:0,他引:1
Senftleben U Cao Y Xiao G Greten FR Krähn G Bonizzi G Chen Y Hu Y Fong A Sun SC Karin M 《Science (New York, N.Y.)》2001,293(5534):1495-1499
In mammals, the canonical nuclear factor kappaB (NF-kappaB) signaling pathway activated in response to infections is based on degradation of IkappaB inhibitors. This pathway depends on the IkappaB kinase (IKK), which contains two catalytic subunits, IKKalpha and IKKbeta. IKKbeta is essential for inducible IkappaB phosphorylation and degradation, whereas IKKalpha is not. Here we show that IKKalpha is required for B cell maturation, formation of secondary lymphoid organs, increased expression of certain NF-kappaB target genes, and processing of the NF-kappaB2 (p100) precursor. IKKalpha preferentially phosphorylates NF-kappaB2, and this activity requires its phosphorylation by upstream kinases, one of which may be NF-kappaB-inducing kinase (NIK). IKKalpha is therefore a pivotal component of a second NF-kappaB activation pathway based on regulated NF-kappaB2 processing rather than IkappaB degradation. 相似文献
84.
云南高原甘薯地方品种征集鉴定研究 总被引:6,自引:0,他引:6
自1993年以来,分别深入到云南省的14个地、州、市,45个县、区实地征集甘薯地方品种资源。1995~1996年将收集到的105份地方品种材料进行田间比较鉴定。对地区来源相同,名称相似的品种材料进行分类比较,初步认定。根据植物学形态特征和生理生态特性,对一些同名异种,异名同种的品种材料进行了认真的区分、整理、归并。将全省所征集到的105份甘薯地方品种材料归并为40份。并经生产力鉴定,筛选出“瑞丽紫红皮”、“普洱黄山芋”等一批具有推广潜力的优良地方品种,可在云南省甘薯生产上逐步推广使用。 相似文献
85.
Fong LG Frost D Meta M Qiao X Yang SH Coffinier C Young SG 《Science (New York, N.Y.)》2006,311(5767):1621-1623
Progerias are rare genetic diseases characterized by premature aging. Several progeroid disorders are caused by mutations that lead to the accumulation of a lipid-modified (farnesylated) form of prelamin A, a protein that contributes to the structural scaffolding for the cell nucleus. In progeria, the accumulation of farnesyl-prelamin A disrupts this scaffolding, leading to misshapen nuclei. Previous studies have shown that farnesyltransferase inhibitors (FTIs) reverse this cellular abnormality. We tested the efficacy of an FTI (ABT-100) in Zmpste24-deficient mice, a mouse model of progeria. The FTI-treated mice exhibited improved body weight, grip strength, bone integrity, and percent survival at 20 weeks of age. These results suggest that FTIs may have beneficial effects in humans with progeria. 相似文献
86.
Zhu GY Li YW Hau DK Jiang ZH Yu ZL Fong WF 《Journal of agricultural and food chemistry》2011,59(1):200-205
Ginseng, the root of Panax ginseng C. A. Meyer (Araliaceae), is one of the most important traditional medicines and functional foods. A detailed phytochemical investigation on the roots of P. ginseng led to the isolation of 6 new natural protopanaxatriol (PPT)-type ginsenosides, ginsenosides Re(1)-Re(6) (compounds 1-6), along with 10 known PPT-type ginsenosides. Their structures were elucidated on the basis of chemical and spectroscopic analyses, including high-resolution mass spectrometry (HRMS) and 1D and 2D nuclear magnetic resonance (NMR). The unusual α-D-glucopyranosyl-(1→3)-β-D-glucopyranosyl sugar chain, as found in compounds 1 and 2, is reported in the genus Panax for the first time. 相似文献
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