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991.
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A new species of Rubiaceae, Spiradiclis densa, is described and illustrated from southwestern China. It is similar to S. tomentosa, but differs in the elliptic or oblong leaf blades, distylous flowers and inner sides of corolla tube with dense pubescence near throat. The conservation status of the new species is preliminarily assessed as ‘Vulnerable’ according to IUCN categories and criteria.  相似文献   
993.
Plants experiencing salt‐induced stress often reduce cytokinin levels during the early phases of stress‐response. Interestingly, we found that the cytokinin content in the apple rootstock “robusta” was maintained at a high level under salt stress. Through screening genes involved in cytokinin biosynthesis and catabolism, we found that the high expression levels of IPT5b in robusta roots were involved in maintaining the high cytokinin content. We identified a 42 bp deletion in the promoter region of IPT5b, which elevated IPT5b expression levels, and this deletion was linked to salt tolerance in robusta×M.9 segregating population. The 42 bp deletion resulted in the deletion of a Proline Response Element (ProRE), and our results suggest that ProRE negatively regulates IPT5b expression in response to proline. Under salt stress, the robusta cultivar maintains high cytokinin levels as IPT5b expression cannot be inhibited by proline due to the deletion of ProRE, leading to improve salt tolerance.  相似文献   
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Liu  Shuai  Li  Su  Fan  Xiao-Yang  Yuan  Guo-Di  Hu  Tao  Shi  Xian-Meng  Huang  Jun-Biao  Pu  Xiao-Yan  Wu  Chuan-Sheng 《Photosynthesis research》2019,141(2):245-257
Photosynthesis Research - Chlorophyll content in lichens is routinely used as an accurate indicator of lichen vigor, interspecific differences, and the effect of site-related environmental...  相似文献   
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Li  Liuli  Li  Hao  Qu  Peng  Xiao  Mingyang  Zhang  Guopei  Zhang  Qianye  Cai  Yuan  Jin  Cuihong  Yang  Jinghua  Wu  Shengwen  Lu  Xiaobo 《Biological trace element research》2019,191(1):126-134

Lead and di-2-ethylhexyl phthalate (DEHP) are widely distributed in the environment, and their neurotoxicity has caused a widespread concern. The complexity of environmental exposure provides the possibility of their combined exposure. The present study aims to describe a joint neurotoxicity and clarify the potential mechanism after combined exposure to lead and DEHP. A 2 × 3 factorial design was used to analyze either single effects or their interaction by a subchronic lead and DEHP exposure model of the male weaning rats. Similar to the previous study, lead or DEHP single exposure showed an increased neurotoxicity. Interestingly, our neurobehavioral test showed the rats in the combined exposure groups had a better ability of learning and memory compared with the single-exposure ones. It seemed to reflect an antagonism joint action in neurotoxicity after combined exposure. The content of dehydroepiandrosterone (DHEA) in serum and the mRNA level of brain-derived neurotrophic factor (Bdnf) in the hippocampus showed a similar trend to the ability of learning and memory. However, there was insufficient evidence to support the joint action on some indexes of oxidative stress such as malondialdehyde (MDA), the ratio of reduced glutathione(GSH) to oxidized glutathione(GSSG), γglutamylcysteine synthetase (γ-GCS), glutathione-s transferase (GST), and nuclear factor E2-related factor 2 (Nrf2) mRNA expression in the hippocampus. In a word, our current study reminded a unique antagonism joint action of neurotoxicity after combined exposure to lead and DEHP, which may contribute to understanding some shallow mechanism of the joint toxicity due to the complexity of environmental pollutant exposure.

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Zhang  Hui  Zhang  Lu  Han  Junyou  Qian  Zhiyuan  Zhou  Bingying  Xu  Yunmin  Wu  Gang 《Plant molecular biology》2019,100(6):571-578
Plant Molecular Biology - A mutation in the nuclear localization signal of squamosa promoter binding like-protein 9 (SPL9) delays vegetative phase change by disrupting its nuclear localization. The...  相似文献   
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