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动物传粉在全球生态系统中提供重要服务,全球农业生产对动物传粉服务的需求稳定增长。油茶是我国特有的重要木本油料植物,栽培历史悠久,由于严格自交不亲和而高度依赖动物传粉。基于我国油茶产业发展的新形势,从资源分配和花粉限制等生态因素系统分析了油茶产量受限制的原因,提出油茶的传粉者限制效果等同于花粉限制效果,人工引入潜在的高效传粉者是解除油茶资源限制措施和传粉生态限制措施之间冲突、提高油茶产量的有效途径。论述了人工引入传粉者传粉服务的优势和挑战。对人工引入传粉者,特别是外来传粉者所面临的潜在风险和控制途径进行了梳理,提出从传粉生态服务解决油茶产量和质量问题的新思路。全文旨在为人工引入传粉者在油茶丰产中的作用提供理论与科学依据,以期促进油茶产业健康有序发展。 相似文献
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Chaomurilege Zu Yanhui Miyagi Atsuko Hashida Shin-Nosuke Ishikawa Toshiki Yamaguchi Masatoshi Kawai-Yamada Maki 《Journal of plant research》2023,136(1):97-106
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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Quan Zhang Fengyun Chen Ansar Javeed Miaofeng Wang Ranran Si Jiaxing Li Bingnan Han 《化学与生物多样性》2023,20(6):e202300445
Development of suitable antimicrobial biomaterials for hygienic wound dressing and healing is an important requirement for medical application. Durable mechanical properties increase the application range of biomaterial in different environmental and biological conditions. Due to the inherent brittleness of silk fibroin (SF), polyurethane fiber (PUF) was used to modify SF containing actinomycin X2 (Ac.X2) to prepare silk fibroin@actinomycin X2/polyurethane fiber (ASF/PUF) blend membranes. The ASF/PUF blend membrane was developed by solution casting method. Incorporation of PUF improved the flexibility of material and introduction of Ac.X2 has increased antibacterial activity of materials. Excellent mechanical properties (tensile strength up to 25.7 MPa and elongation at break up to 946.5 %) of 50 % SF+50 % PUF blend membrane were proved by tensile testing machine. FT-IR spectra, TGA, contact angle and DMA were tested to prove the blend membrane's physico-chemical characteristics. ASF/PUF blend membrane displayed satisfactory antibacterial activity against S. aureus, and the cytotoxicity tests showed that the blend membrane has better biosafety compared to directly applied Ac.X2 in soluble form. These results suggest that the modification of SF through PUF for development of flexible antibacterial membranes has great potential application value in the field of silk-like material fabrication. 相似文献
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本文对华北地区蓟属CirsiumAdans.16种植物的甲醇提取液紫外吸收光谱(UV)进行了比较研究。结果表明,蓟属植物的叶较其它部位的UV具有较好的稳定性和代表性,其光谱的特征可以作为属下分类的重要依据,其化学分类结果与形态分类基本一致。根据光谱特征,结合形态学及有关的细胞学和同工酶方面的资料,重新确立了Sect.Pseudo-Eriolepis(Nakai)Kitam.和C.segetumBge.的组级和种级地位,最后,作者进一步讨论了光谱特征在化学分类中的意义。 相似文献
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Summary A male patient with an interstitial deletion 13q14q31 is described. Our necropsy findings included a left retinoblastoma and several gross internal malformations. In this paper we reaffirm that band 13q14 is involved in cases of retinoblastoma and we propose, after studying accompanying cases of total or partial long arm trisomies 13, that the loss of specific 13q bands, from 13q14 to 13q31 is responsible for the congenital defects we are describing. 相似文献
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Characterization of interleukin 2 stimulated 65-kilodalton phosphoprotein in human T cells 总被引:3,自引:0,他引:3
We have characterized the cellular proteins which are rapidly phosphorylated by interleukin 2 (IL 2) in a human IL 2 dependent cell line. When treated with IL 2, the phosphorylation of five proteins, 65, 50, 37, 24, and 21 kDa, was found in IL 2 dependent cell lines by two-dimensional gel electrophoretic analysis. After cell conversion from an IL 2 dependent state to an IL 2 independent state, one of the five phosphoproteins, the 65-kDa protein, became constitutively phosphorylated even without addition of IL 2. Also, in other IL 2 independent cell lines, such as KUT-2 and HUT-102, constitutive phosphorylation of the 65-kDa protein occurred without IL 2-stimulation. So our researchers were focused on biochemical characterization of the 65-kDa protein. It was found that the 65-kDa protein was one of the major cellular proteins by comparing the results of two-dimensional gel electrophoretic analysis of [32P]Pi-labeled and [3H]leucine-labeled cellular proteins and peptide mapping analysis. Subcellular fractionation studies indicated that the 65-kDa protein is a cytosol protein. The 65-kDa protein was purified from cytosol of a human T cell line, and its amino acid composition and amino acid sequences of its three oligopeptides were determined. It was found that the 65-kDa protein is identical with 1-plastin. 相似文献