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961.
Mu Dan Pan Chenyang Qi Zehua Qin Huaguang Li Qin Liang Kexin Rao Yuchun Sun Tingzhe 《Plant Growth Regulation》2021,95(1):111-120
Plant Growth Regulation - The tea green leafhopper (Empoasca onukii Matsuda) is a severe pest for the tea plant (Camellia sinensis (L.) O. Ktze), which significantly reduces the tea yields and... 相似文献
962.
Jie Wang Long‐Jiang Yu Wenda Wang Qiujing Yan Tingyun Kuang Xiaochun Qin Jian‐Ren Shen 《植物学报(英文版)》2021,63(7):1367-1381
Photosystem I (PSI) is one of the two photosystems in photosynthesis, and performs a series of electron transfer reactions leading to the reduction of ferredoxin. In higher plants, PSI is surrounded by four light-harvesting complex I (LHCI) subunits, which harvest and transfer energy efficiently to the PSI core. The crystal structure of PSI-LHCI supercomplex has been analyzed up to 2.6 Å resolution, providing much information on the arrangement of proteins and cofactors in this complicated supercomplex. Here we have optimized crystallization conditions, and analyzed the crystal structure of PSI-LHCI at 2.4 Å resolution. Our structure showed some shift of the LHCI, especially the Lhca4 subunit, away from the PSI core, suggesting the indirect connection and inefficiency of energy transfer from this Lhca subunit to the PSI core. We identified five new lipids in the structure, most of them are located in the gap region between the Lhca subunits and the PSI core. These lipid molecules may play important roles in binding of the Lhca subunits to the core, as well as in the assembly of the supercomplex. The present results thus provide novel information for the elucidation of the mechanisms for the light-energy harvesting, transfer and assembly of this supercomplex. 相似文献
963.
Qin Long Miki Naoko H. Zhang Guosheng Fujii Yoshiharu 《Landscape and Ecological Engineering》2021,17(3):245-251
Landscape and Ecological Engineering - Juniperus sabina L. is a native evergreen conifer of the Mu Us Sandy Land. It has prostrating stems that can prevent sand shifting and is an important... 相似文献
964.
965.
Daniel C. Capaldi Alessandra Eleuteri Qin Chen Raymond F. Schinazi 《Nucleosides, nucleotides & nucleic acids》2013,32(4):403-416
Abstract The synthesis of pyrimidine nucleosides, cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]uracil (4) cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]thymine (5) and cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]cytosine (6) and their corresponding trans isomers is described. Compound 4 showed modest, selective activity against human immunodeficiency virus in acutely infected primary human lymphocytes. 相似文献
966.
967.
Guangxia Cui Huijie Leng Ke Wang Jianwei Wang Sainan Zhu Jing Jia Xing Chen Weiguang Zhang Lihua Qin Wenpei Bai 《PloS one》2013,8(12)
This study aims to evaluate the effects of Remifemin (isopropanolic extract of Cimicifuga Racemosa) on postmenopausal osteoporosis. 120 female Sprague-Dawley rats were randomly assigned to four groups: sham surgery with vehicle, ovariectomy with vehicle, ovariectomy with estradiol valerate, or ovariectomy with Remifemin. Daily oral administrations of the vehicle, estradiol valerate, or Remifemin began 2 weeks after surgery and lasted to 4, 8, or 12 weeks. Ten rats in each group were sacrificed at each timestep with assessment of bone mineral density, trabecular bone structure, and biomechanical parameters of the femur and lumbar vertebra. Bone turnover markers were evaluated 12 weeks after surgery. Both drugs prevented bone density loss in the distal end of the femur and preserved the trabecular bone structure in both the lumbar vertebra and distal end of the femur following ovariectomy. Both drugs protected bone stiffness at the tested regions and reduced bone reabsorption in ovariectomized rats. The preventive effects of Remifemin against bone-loss can rival those of estradiol valerate if treatment duration is adequately extended. In conclusion, Remifemin may demonstrate equivalent effects to estradiol valerate in terms of preventing postmenopausal osteoporosis. 相似文献
968.
969.
The structures, stabilities, and aromaticities of a series of (BCO) n (CH)4–n NH (n?=?0–4), (BCO) n (CH)4–n O (n?=?0–4), and (BCO) n (CH)4–n S (n?=?0–4) clusters were investigated at the B3LYP density functional level of theory. The most stable positional isomers of the individual clusters were obtained. All of the calculated CO binding energies were exothermic, suggesting that these BCO-substituted species are stable. Calculated differences in strain energy between the BCO-substituted structures and their corresponding hydrocarbon clusters were all exothermic, indicating that the BCO-substituted structures are less strained. The negative nucleus-independent chemical shift (NICS) values obtained show that these BCO-substituted clusters are aromatic compounds, in good agreement with the aromaticities of the corresponding hydrocarbon species. To aid further experimental investigations, CO-stretching frequencies were also computed. 相似文献
970.
Kejian Wang Jiazhi Sun Shufeng Zhou Chunling Wan Shengying Qin Can Li Lin He Lun Yang 《PLoS computational biology》2013,9(11)
Small drug molecules usually bind to multiple protein targets or even unintended off-targets. Such drug promiscuity has often led to unwanted or unexplained drug reactions, resulting in side effects or drug repositioning opportunities. So it is always an important issue in pharmacology to identify potential drug-target interactions (DTI). However, DTI discovery by experiment remains a challenging task, due to high expense of time and resources. Many computational methods are therefore developed to predict DTI with high throughput biological and clinical data. Here, we initiatively demonstrate that the on-target and off-target effects could be characterized by drug-induced in vitro genomic expression changes, e.g. the data in Connectivity Map (CMap). Thus, unknown ligands of a certain target can be found from the compounds showing high gene-expression similarity to the known ligands. Then to clarify the detailed practice of CMap based DTI prediction, we objectively evaluate how well each target is characterized by CMap. The results suggest that (1) some targets are better characterized than others, so the prediction models specific to these well characterized targets would be more accurate and reliable; (2) in some cases, a family of ligands for the same target tend to interact with common off-targets, which may help increase the efficiency of DTI discovery and explain the mechanisms of complicated drug actions. In the present study, CMap expression similarity is proposed as a novel indicator of drug-target interactions. The detailed strategies of improving data quality by decreasing the batch effect and building prediction models are also effectively established. We believe the success in CMap can be further translated into other public and commercial data of genomic expression, thus increasing research productivity towards valid drug repositioning and minimal side effects. 相似文献