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51.
A new Mn(II) complex, [Mn2(edta)(H2O)]n·nH2O (1) (H4edta = ethylenediaminetetraacetic acid) has been synthesized by the reaction of MnCl2·4H2O and H4edta under hydrothermal conditions, and was characterized by single-crystal X-ray diffraction study, variable temperature (1.8-300 K) magnetic measurement, and thermal gravity analysis. The result of X-ray crystallographic analysis reveals that complex 1 is the first two-dimensional (2D) Mn-edta coordination polymer with a grid-like (4,4)-topology, which is built from Mn-carboxylate chains and entirely deprotonated edta4− ligands with a maximum denticity. The variable temperature magnetic data indicate that complex 1 exhibits strong antiferromagnetic couplings. 相似文献
52.
Leifu Chang Xianwei Liu Yanbing Li Cui-Cui Liu Fan Yang Jindong Zhao Sen-Fang Sui 《Cell research》2015,25(6):726-737
Phycobilisomes (PBSs) are light-harvesting antennae that transfer energy to photosynthetic reaction centers in cyanobacteria and red algae. PBSs are supermolecular complexes composed of phycobiliproteins (PBPs) that bear chromophores for energy absorption and linker proteins. Although the structures of some individual components have been determined using crystallography, the three-dimensional structure of an entire PBS complex, which is critical for understanding the energy transfer mechanism, remains unknown. Here, we report the structures of an intact PBS and a PBS in complex with photosystem II (PSII) from Anabaena sp. strain PCC 7120 using single-particle electron microscopy in combination with biochemical and molecular analyses. In the PBS structure, all PBP trimers and the conserved linker protein domains were unambiguously located, and the global distribution of all chromophores was determined. We provide evidence that ApcE and ApcF are critical for the formation of a protrusion at the bottom of PBS, which plays an important role in mediating PBS interaction with PSII. Our results provide insights into the molecular architecture of an intact PBS at different assembly levels and provide the basis for understanding how the light energy absorbed by PBS is transferred to PSII. 相似文献
53.
Guang-cong Liu Guo-yuan Sui Guang-ying Liu Yang Zheng Yan Deng Yan-yan Gao Lie Wang 《PloS one》2013,8(11)
Background
Although transfusion-transmitted infection of hepatitis B virus (HBV) threatens the blood safety of China, the nationwide circumstance of HBV infection among blood donors is still unclear.Objectives
To comprehensively estimate the prevalence of HBsAg positive and HBV occult infection (OBI) among Chinese volunteer blood donors through bayesian meta-analysis.Methods
We performed an electronic search in Pub-Med, Web of Knowledge, Medline, Wanfang Data and CNKI, complemented by a hand search of relevant reference lists. Two authors independently extracted data from the eligible studies. Then two bayesian random-effect meta-analyses were performed, followed by bayesian meta-regressions.Results
5957412 and 571227 donors were identified in HBsAg group and OBI group, respectively. The pooled prevalence of HBsAg group and OBI group among donors is 1.085% (95% credible interval [CI] 0.859%∼1.398%) and 0.094% (95% CI 0.0578%∼0.1655%). For HBsAg group, subgroup analysis shows the more developed area has a lower prevalence than the less developed area; meta-regression indicates there is a significant decreasing trend in HBsAg positive prevalence with sampling year (beta = −0.1202, 95% −0.2081∼−0.0312).Conclusion
Blood safety against HBV infection in China is suffering serious threats and the government should take effective measures to improve this situation. 相似文献54.
Yang Xiaolin Sun Beibei Gao Wangsheng Chen Yuanquan Sui Peng 《The International Journal of Life Cycle Assessment》2019,24(3):371-385
The International Journal of Life Cycle Assessment - Low carbon footprint agriculture has received increasing attention in the effect of reducing greenhouse gas emissions and mitigating climate... 相似文献
55.
Molecular diversity and phylogeny of rhizobia associated with wild legumes native to Xinjiang, China
Han TX Wang ET Han LL Chen WF Sui XH Chen WX 《Systematic and applied microbiology》2008,31(4):287-301
A total of 111 rhizobial strains were isolated from wild legumes in Xinjiang, an isolated region of northwest China. Nine genomic species belonging to four genera of Rhizobium, Mesorhizobium, Ensifer, and Bradyrhizobium were defined among these strains based on the characterization of amplified 16S ribosomal DNA restriction analysis (ARDRA), restriction fragment length polymorphism (RFLP) analysis of 16S-23S rDNA intergenic spacers (IGS), 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). Twenty-five nodC types corresponding to eight phylogenetic clades were divided by RFLP and sequence analysis of the PCR-amplified nodC gene. The acid-producing Rhizobium and Mesorhizobium species were predominant, which may be related to both the local environments and the hosts sampled. The present study also showed the limitation of using nod genes to estimate the host specificity of rhizobia. 相似文献
56.
Jiang W Allan G Chen X Fiordeliso JJ Linton O Tannenbaum P Xu J Zhu P Gunnet J Demarest K Lundeen S Sui Z 《Steroids》2006,71(11-12):949-954
A novel series of steroidal compounds were designed and synthesized with various phosphorus-containing groups on the 17beta-side chain as progesterone receptor antagonists. The structure-activity relationships of these compounds are discussed. Selected compounds were tested in an rat progesterone-sensitive assay. Some of these compounds are more potent than mifepristone, with a better selectivity profile in differentiating progesterone receptor from glucocorticoid receptor. 相似文献
57.
Zhang SY Wang JZ Li JJ Wei DL Sui HS Zhang ZH Zhou P Tan JH 《Biology of reproduction》2011,84(4):672-681
Although studies of both humans and animals suggest detrimental effects of psychological (restraint) stress on reproduction, reports concerning the direct effect of psychological (restraint) stress on the oocyte are few and conflicting. In the present study, a restraint system that allows mice free intake of feed and water while restraining their movement was established, and effects of maternal restraint on oocyte competence were examined by observing embryo development in vitro and in vivo. The results indicated that restraint stress applied to both gonadotropin-stimulated and unstimulated females during oocyte growth and maturation increased their plasma cortisol level but impaired ovulation and oocyte developmental potential. Injection of cortisol also decreased oocyte developmental potential in both stimulated and unstimulated mice. However, whereas restraint stress reduced the plasma follicle-stimulating hormone (FSH) level of unstimulated mice, injection of cortisol did not. Because the stimulated mice had received very high doses of FSH and luteinizing hormone from injection with equine chorionic gonadotropin injection, the results suggested that whereas cortisol acts directly on the ovary to damage the oocyte, restraint stress impairs oocyte competence by actions on both the hypothalamic-pituitary-gonadal and the hypothalamic-pituitary-adrenal axes. However, exposing the cumulus-oocyte complexes (COCs) to physiological levels of cortisol did not affect oocyte nuclear and cytoplasmic maturation in vitro. Thus, cortisol might have impaired ovulation and oocyte potential by an indirect effect on ovarian tissues other than the COCs. 相似文献
58.
神经系统中的IgSF蛋白是一类重要的神经细胞表面分子,种类繁多,功能多样,其中一类分子缺乏跨膜区,通过GPI锚结合在细胞膜上,表现出结构和功能的特异性。本文对该类神经元GPI锚定蛋白分子作一系统介绍。根据结构特点,神经元GPI锚定蛋白分子可分为三类,各类分子通过Ig结构域与其自身或其它蛋白分子进行顺式或反式结合,调节神经细胞活动。 相似文献
59.
Endothelin (ET) converting enzyme 1 (ECE1) is well known for its critical role in the process of ET. Recent studies have demonstrated that two genetic variants of ECE1 gene, rs212528 and rs213045 (C338A), are associated with hypertension and atherosclerosis formation. To investigate the association between the ECE1 gene polymorphisms and ischemic stroke (IS) in Chinese population. With a candidate loci strategy, we conducted a case–control study involving 381 IS cases and 366 non-IS controls in Han population of the Northern China. Two single nucleotide polymorphisms of ECE1 were genotyped and assessed the association with the risk of IS. Furthermore, stratified analyses were also carried out to evaluate the association between the gender or two etiologic subtypes [small-artery occlusion (SAO) and large-artery atherosclerosis (LAA)] and IS. Compared with rs213045 G homozygote, rs213045 TG genotype and rs213045 TT/TG genotypes are in dominant model significantly increased the risk of IS [adjusted odds ratio (OR) = 1.47, 95 % confidence interval (CI) = 1.04–2.07, P = 0.03; adjusted OR = 1.43, 95 % CI = 1.04–1.99, P = 0.029, respectively]. However, we did not find the significant association between the ECE1 gene polymorphisms and SAO or LAA of IS in this study. Our results indicated that ECE1 gene polymorphisms may contribute to the susceptibility of IS in Han population of the Northern China. 相似文献
60.
Nilantha Sirisoma Azra Pervin Hong Zhang Songchun Jiang J. Adam Willardsen Mark B. Anderson Gary Mather Christopher M. Pleiman Shailaja Kasibhatla Ben Tseng John Drewe Sui Xiong Cai 《Bioorganic & medicinal chemistry letters》2010,20(7):2330-2334
As a continuation of our efforts to discover and develop apoptosis inducing N-methyl-4-(4-methoxyanilino)quinazolines as novel anticancer agents, we explored substitution at the 5-, 6-, 7-positions of the quinazoline and replacement of the quinazoline by other nitrogen-containing heterocycles. A small group at the 5-position was found to be well tolerated. At the 6-position a small group like an amino was preferred. Substitution at the 7-position was tolerated much less than at the 6-position. Replacing the carbon at the 8-position or both the 5- and 8-positions with nitrogen led to about 10-fold reductions in potency. Replacement of the quinazoline ring with a quinoline, a benzo[d][1,2,3]triazine, or an isoquinoline ring showed that the nitrogen at the 1-position is important for activity, while the carbon at the 2-position can be replaced by a nitrogen and the nitrogen at the 3-position can be replaced by a carbon. Through the SAR study, several 5- or 6-substituted analogs, such as 2a and 2c, were found to have potencies approaching that of lead compound N-(4-methoxyphenyl)-N,2-dimethylquinazolin-4-amine (1g, EP128495, MPC-6827, Azixa®). 相似文献