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11.
通过顶置光源植物生长室控制380和760 μmol·mol-1 2个CO2浓度水平,研究了磷缺乏与正常供磷条件下,CO2浓度升高对玉米/大豆间作、玉米单作和大豆单作3种种植模式下作物株高、茎粗、叶面积及干物质积累的影响.结果表明:(1)CO2浓度升高能显著增加单/间作玉米、大豆的株高、茎粗、叶面积、根干重、地上部干重及总干重.(2)CO2浓度升高对供磷水平下单、间作玉米大豆的株高、茎粗、叶面积及干物质积累量增加的正效应均大于缺磷处理.(3)两种CO2浓度下,间作大豆与单作大豆生长差异不显著,而间作玉米较单作玉米有明显的生长优势,且供磷和CO2浓度的升高均能够促进这种优势. 相似文献
12.
Jie Zhang Yuhong Chen Yu Xu Mian Li Tiange Wang Baihui Xu Jichao Sun Min Xu Jieli Lu Yufang Bi 《PloS one》2013,8(6)
Background
Micro-albuminuria has been well established as one of the risk factors of metabolic syndrome (MetS). However, the association of MetS and its components with low-grade albuminuria among those with normal urinary albumin excretion has not been clearly elucidated in Chinese population.Methodology and Findings
A cross-sectional study was conducted among 9,579 participants with normal urinary albumin excretion, who were recruited from Jia Ding District, Shanghai, China. The single-void first morning urine sample was collected for urinary albumin and creatinine measurements, and urinary albumin-to-creatinine ratio (UACR) was calculated as urinary albumin divided by creatinine. Low-grade albuminuria was classified as sex-specific upper UACR quartile in this population. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. The prevalence of MetS and its components increased across the UACR quartiles (all P trend <0.01). A multivariable adjusted logistic regression analysis revealed that the prevalence of MetS was gradually elevated according to the UACR quartiles (adjusted odds ratios [ORs] were 1.14, 1.24 and 1.59 for UACR quartiles 2, 3 and 4, compared with the lowest quartile; P trend<0.0001). In the further stratified logistic regression analyses, the associations between low-grade albuminuria and MetS were significant in both sex strata (male and female), both age strata (<60 and ≥60 years), both body mass index strata (<24 and ≥24 kg/m2), and both diabetes strata (yes and no). Compared to the lowest UACR quartile, the participants in the highest quartile of UACR had the highest prevalence of central obesity (OR = 1.43; 95%CI = 1.25–1.63), high blood pressure (OR = 1.64; 95%CI = 1.43–1.87), hyperglycemia (OR = 1.52; 95%CI = 1.30–1.78) and high triglycerides (OR = 1.19; 95%CI = 1.04–1.37).Conclusions and Significance
Low-grade albuminuria was significantly associated with the increasing prevalence of MetS and its components in the middle-aged and elderly Chinese population with normal urinary albumin excretion. 相似文献13.
Association between the change in body mass index from early adulthood to midlife and subsequent type 2 diabetes mellitus 下载免费PDF全文
Yiming Mu Chao Liu Jiajun Zhao Lulu Chen Qiang Li Tao Yang Li Yan Qin Wan Shengli Wu Yan Liu Guixia Wang Zuojie Luo Xulei Tang Gang Chen Yanan Huo Zhengnan Gao Qing Su Youmin Wang Guijun Qin Huacong Deng Xuefeng Yu Feixia Shen Li Chen Liebin Zhao Jichao Sun Lin Ding Yu Xu Min Xu Meng Dai Tiange Wang Di Zhang Jieli Lu Yufang Bi Shenghan Lai Donghui Li Weiqing Wang Guang Ning 《Obesity (Silver Spring, Md.)》2016,24(3):703-709
14.
The ubiquitin-like conjugation reactions, ATG8/microtubule-associated protein 1 light chain 3/MAP1LC3 (LC3) to phosphatidylethanolamine (PE) and ATG12 to ATG5, are biochemical hallmarks for autophagy, a cellular process that degrades bulk cellular proteins and organelles. The two conjugation reactions share the same E1-like enzyme ATG7 but have different E2-like enzymes, ATG3 for LC3-PE and ATG10 for ATG12-ATG5. In cells, ATG12-ATG5 conjugation appears to be required for LC3-PE conjugation. Previously, in vitro reconstitution of LC3-PE conjugation, but not the upstream ATG12-ATG5 conjugation, was reported. In this study, we describe for the first time the de novo reconstitution of mammalian ATG12-ATG5 conjugation by using purified recombinant proteins. We show that ATG7, ATG10 and ATP as an energy source are all essential for ATG12-ATG5 conjugation, and mutation of the specific lysine residue of ATG5 for ATG12 conjugation abrogates the reaction. Furthermore, a potent stimulating activity for ATG12-ATG5 conjugation was detected in mammalian cell extracts, and was surprisingly identified as ribosomes. Our detail biochemical analyses indicate that the ribonucleic acid (RNA) component of ribosomes is both necessary and sufficient for this stimulation. 相似文献
15.
Chen Yufang Shen Yixin Wang Kuan Qi Yan Niu Wenxin Wang Yan 《Biomechanics and modeling in mechanobiology》2022,21(5):1573-1584
Biomechanics and Modeling in Mechanobiology - Spinal cord injury patients are prone to develop deep tissue injury because of long-term mechanical load. However, there is a lack of statistical... 相似文献
16.
Zhang Xiaonan Lu Yufang Yang Ting Kronzucker Herbert J. Shi Weiming 《Plant and Soil》2019,441(1-2):253-259
Plant and Soil - Depending on the availability and stoichiometry of nutrients in soil, microbes and plants can compete for the same resources. In this study we aimed to test how microbial nutrient... 相似文献
17.
金线蛙入蛰时几项生理常数间的关系研究 总被引:1,自引:0,他引:1
本文经统计学分析处理,表明金钱蛙(Ranaplancyi)入蛰时的体长与体重、胴体重和体重与肝重、脂肪体重、生殖腺重之间均存在非常显著的线性相关关系。 相似文献
18.
19.
污染土壤中多环芳烃生物降解的调控研究 总被引:23,自引:6,他引:17
选用温度、湿度、表面活性剂TW80和CNP比4个因素为调控因子,采用正交法进行周期为150天的实验研究.结果表明,30天后,土壤中PAHs的降解率可达44.5~74.6%,60天后,达70.4~93.7%,降解率的不同与调控条件显著相关.在此期间,降解最佳条件为40℃,湿度25%,CNP比为120101,TW80分别为200~500mg·kg-1.实验结束时,土壤中PAHs的降解率达91.2~99.8%.降解的最佳条件是40℃,湿度15%.经R值判别表明,不同时期各因子对PAHs降解影响有所不同.温度对PAHs降解影响较大,表面活性剂对土壤中PAHs的生物降解有调控作用. 相似文献
20.
Suxing Shen Jing Li Qi Guo Wen Zhang Xiuyang Wang Liyuan Fu Linke Li Yufang An Weixi Liu Hongyun Li Tao Huang Zedan Zhang Kaijun Niu 《PloS one》2015,10(3)