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Journal of Plant Research - Chloroplast-localized NAD kinase (NADK2) is responsible for the production of NADP+, which is an electron acceptor in the linear electron flow of photosynthesis. The...  相似文献   
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从三尖杉当年生幼茎和未成熟假种皮诱导出了愈伤组织,对愈伤组织进行了培养研究,HPLC分析表明其紫杉醇和10-dABⅢ分别为细胞干重的0.00209%和0.0122%。三尖杉可望成为紫杉醇来源的新途径。  相似文献   
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Plasmonic nanorods and their clusters are the fundamental units in plasmonic nanoantenna engineering. A theory that can predict the resonance of single nanorod already exists but is in lack for a heterodimer. Here, we propose a model combining the effective circuit theory for the response of spherical nanoparticles together with standard transmission line theory for hemispherically capped nanorod antennas. The resonances of multiple orders are predictable by defining the reflection phase at the terminals of such antennas, in both symmetric and asymmetric coupled nanorods. The theoretical results compare favorably with full-wave finite element numerical calculations. By the analytical formula, it is easy to control the length of the antennas for regulating the cooperative resonant properties and consequently the radiation characteristics of a nearby electric dipole. Consequently, we obtain both commensurate and incommensurate resonance features in such nanorod-based heterodimer antennas, showing respectively cumulative and selective responses from the individual nanorods.  相似文献   
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The case‐control study was designed to investigate the genetic effects of interferon‐gamma (IFN‐γ) rs2069727 and rs1861494 polymorphisms on ankylosing spondylitis (AS) susceptibility in a Chinese Han population. Blood samples were collected from 108 AS patients and 110 healthy controls. IFN‐γ polymorphisms were genotyped by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Hardy‐Weinberg equilibrium (HWE) test was performed in control group. Odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using chi‐square test to evaluate the association between AS susceptibility and IFN‐γ polymorphisms, and the results were adjusted by logistic regressive analysis. The frequency of rs2069727 CC genotype was much higher in cases than that in controls, suggested its significant association with increased AS risk (adjusted OR = 5.899, 95% CI = 1.563‐22.261; P = .009). In addition, C allele also showed close association with increased risk of AS (adjusted OR = 2.052, 95% CI = 1.286‐1.704, P  = 0 .003). While the genotype and allele frequencies of IFN‐γ rs1861494 polymorphism were not significantly different between patients and controls (P  > 0.05 for all), IFN‐γ rs2069727 polymorphism is significantly associated with increased AS risk in a Chinese Han Population.  相似文献   
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Angiosperm reproductive development is a complex event that includes floral organ development, male and female gametophyte formation and interaction between the male and female reproductive organs for successful fertilization. Previous studies have revealed the redundant function of ATP binding cassette subfamily G (ABCG) transporters ABCG1 and ABCG16 in pollen development, but whether they are involved in other reproductive processes is unknown. Here we show that ABCG1 and ABCG16 were not only expressed in anthers and stamen filaments but also enriched in pistil tissues, including the stigma, style, transmitting tract and ovule. We further demonstrated that pistil‐expressed ABCG1 and ABCG16 promoted rapid pollen tube growth through their effects on auxin distribution and auxin flow in the pistil. Moreover, disrupted auxin homeostasis in stamen filaments was associated with defective filament elongation. Our work reveals the key functions of ABCG1 and ABCG16 in reproductive development and provides clues for identifying ABCG1 and ABCG16 substrates in Arabidopsis.  相似文献   
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Xu  Tianle  Chen  Xiao  Hou  Yanhui  Zhu  Biao 《Plant and Soil》2021,461(1-2):137-150
Plant and Soil - Plant P acquisition strategies are driven by multiple belowground morphological and physiological traits as well as interactions among these traits. This study aimed to...  相似文献   
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依赖于动物传粉获得繁殖成功的植物的分布与其传粉动物的地理分布有着密切联系。预测未来气候变化对植物及其传粉动物地理分布的影响对生物多样性保护具有重要意义。本文通过对中国-喜马拉雅3种黄耆属(Astragalus)植物, 即弯齿黄耆(A. camptodontus)、黑毛黄耆(A. pullus)和笔直黄耆(A. strictus), 及其传粉熊蜂(Bombus)的野外调查, 以及收集来源于数据库的黄耆和熊蜂的543个物种分布点和13个环境因子数据, 结合物种可能出现的完全扩散、不扩散和仅熊蜂扩散3种迁移模式, 利用MaxEnt模型模拟了3种黄耆属植物与2种传粉熊蜂即橘尾熊蜂(Bombus friseanus)和红束熊蜂(B. rufofasciatus)在历史阶段(1970-2000年)和2100年两种温室气体浓度情景(ssp245和ssp585)下的适宜分布区变化。结果表明: 3种黄耆属植物均主要依赖于熊蜂传粉, 黄耆与其传粉熊蜂的主要适宜分布区为中国-喜马拉雅地区, 到2100年它们的分布区呈现向西北方向扩张的趋势, 而在东南部的分布区减少。当模型中考虑与传粉熊蜂的互作后, 3种黄耆属植物的潜在地理分布范围减少了15.83%-83.98%。在温室气体中低浓度情景(ssp245)下, 3种黄耆属植物与其传粉熊蜂的空间匹配增加, 而在高浓度情景(ssp585)下弯齿黄耆、黑毛黄耆与橘尾熊蜂的空间匹配降低; 如果物种不扩散或仅熊蜂扩散, 笔直黄耆与红束熊蜂的空间匹配降低。气候变化和物种的扩散能力可能引起黄耆与其传粉熊蜂出现空间不匹配。同时, 模型预测显示影响黄耆和熊蜂分布的环境因子不同, 但海拔是最主要的环境因子。由于与传粉者的相互作用对许多植物物种的生命周期具有重要意义, 因而本研究可以更好地理解气候变化对植物与其传粉者空间分布的潜在影响, 特别是对那些地理范围受限制的植物。  相似文献   
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