排序方式: 共有113条查询结果,搜索用时 15 毫秒
21.
22.
开展生态系统服务评估已经成为国土空间功能管治、城市治理、生态产品价值实现等工作中的先行基础动作。生态系统服务的类型和模型方法多,数据需求复杂,传统基于多学科软件开展生态系统服务评估的工作模式知识和技术门槛较高、效率低。当前专业的生态系统服务评估软件多为美国从业人员开发,对我国的数据构成和本地化参数适应性有限。介绍了我国自主开发的生态系统分析软件(城市生态智慧管理系统,IUEMS)的主要功能和应用情况,并将其的生态系统服务评估功能与InVEST、ARIES等国外主流软件在操作逻辑、评估模型、数据取得、空间精度、界面交互五个方面进行了对比。 相似文献
23.
Baolong Wang Xin Wang Chris Wayne Xiangxiang Wang Lei Han Li Ye Qun Zhao Guixiang Jiang Meiqing Feng 《Biotechnology letters》2016,38(5):801-807
Objective
To produce a therapeutic protein (endostatin) by fusion with two fragments of the carboxyl-terminal peptide (CTP) of the human chorionic gonadotropin β-subunit in Pichia pastoris.Results
Two CTP sequences were fused to the C-terminal of human endostatin, and the fusion protein (endo-CTP) was expressed by P. pastoris. Endo-CTP inhibited proliferation of endothelial cells with an IC50 of 7 μg ml?1, and 30 % of cells were annexin V-positive after treatment with 20 μg endo-CTP ml?1 for 48 h. Migration of endothelial cells was inhibited by endo-CTP in a concentration-dependent manner. The half-life of endo-CTP in Sprague–Dawley rats was much longer than that of its commercial counterpart (Endostar).Conclusion
A long-acting endostatin can be produced using CTP technology.24.
Background
The management of thoracolumbar (TL) burst fractures is still controversial. The thoracolumbar injury classification and severity score (TLICS) algorithm is now widely used to guide clinical decision making, however, in clinical practice, we come to realize that TLICS also has its limitations for treating patients with total scores less than 4, for which conservative treatment may not be optimal in all cases.Purpose
The aim of this study is to identify several risk factors for the failure of conservative treatment of TL burst fractures according to TLICS algorithm.Methods
From June 2008 to December 2013, a cohort of 129 patients with T10-l2 TL burst fractures with a TLISC score ≤3 treated non-operatively were identified and included into this retrospective study. Age, sex, pain intensity, interpedicular distance (IPD), canal compromise, loss of vertebral body height and kyphotic angle (KA) were selected as potential risk factors and compared between the non-operative success group and the non-operative failure group.Results
One hundred and four patients successfully completed non-operative treatment, the other 25 patients were converted to surgical treatment because of persistent local back pain or progressive neurological deficits during follow-up. Our results showed that age, visual analogue scale (VAS) score and IPD, KA were significantly different between the two groups. Furthermore, regression analysis indicated that VAS score and IPD could be considered as significant predictors for the failure of conservative treatment.Conclusion
The recommendation of non-operative treatment for TLICS score ≤3 has limitations in some patients, and VAS score and IPD could be considered as risk factors for the failure of conservative treatment. Thus, conservative treatment should be decided with caution in patients with greater VAS scores or IPD. If non-operative management is decided, a close follow-up is necessary. 相似文献25.
Baolong Bao Valerie PestingerYousef I. Hassan Gloria E.O. BorgstahlCarol Kolar Janos Zempleni 《The Journal of nutritional biochemistry》2011,22(5):470-475
Holocarboxylase synthetase (HCS) mediates the binding of biotin to lysine (K) residues in histones H2A, H3 and H4; HCS knockdown disturbs gene regulation and decreases stress resistance and lifespan in eukaryotes. We tested the hypothesis that HCS interacts physically with histone H3 for subsequent biotinylation. Co-immunoprecipitation experiments were conducted and provided evidence that HCS co-localizes with histone H3 in human cells; physical interactions between HCS and H3 were confirmed using limited proteolysis assays. Yeast two-hybrid (Y2H) studies revealed that the N-terminal and C-terminal domains in HCS participate in H3 binding. Recombinant human HCS was produced and exhibited biological activity, as evidenced by biotinylation of its known substrate, recombinant p67. Recombinant histone H3.2 and synthetic H3-based peptides were also good targets for biotinylation by recombinant HCS (rHCS) in vitro, based on tracing histone-bound biotin with [3H]biotin, streptavidin and anti-biotin antibody. Biotinylation site-specific antibodies were generated and revealed that both K9 and K18 in H3 were biotinylated by HCS. Collectively, these studies provide conclusive evidence that HCS interacts directly with histone H3, causing biotinylation of K9 and K18. We speculate that the targeting of HCS to distinct regions in human chromatin is mediated by DNA sequence, biotin, RNA, epigenetic marks or chromatin proteins. 相似文献
26.
目前生态系统生产总值(GEP)核算工作已在全国多地开展,并在不少地方已将其纳入政绩考核指标,但GEP核算中相关生态系统服务多基于实际降雨数据和多年平均降雨数据,导致在进行年际间GEP变化分析时,结果难以反应实际的生态系统质量和数量的变化,从而影响GEP管理应用的效果。本文以深圳为研究案例,提出了更能代表本地降雨一般化特征的可比降雨条件,以及基于主成分分析的确定方法,并且在可比降雨条件和实际降雨条件下核算了可比降雨年和临近年共3种情景下的生态系统生产总值(GEP),分析了不同情景下的GEP构成以及降雨因素对年际间GEP变化的影响能力。研究发现:(1)2019年为深圳可比降雨年,且符合2008—2020年间各年《深圳市气候公报》对降雨情况的阐述;(2)可比降雨条件下,与降雨相关的4项生态系统服务价值(减少泥沙淤积、减少面源污染、涵养水源、削减洪涝)呈年际间增长趋势,实际降雨条件下,减少泥沙淤积、减少面源污染价值增长,涵养水源、削减洪涝价值下降;(3)降雨因素显著影响GEP年际变化,不同降雨条件下,深圳2019—2020年GEP变化差异高达24.78亿元,而可比降雨条件可以有效减少非人为因素... 相似文献
27.
我国澳门特别行政区是世界上人口密度最高的地区之一,人地关系紧张。随着城市和经济的发展,人类空间与生态空间失调,城市生态和人居环境问题不断加剧。在建设美丽湾区、美丽澳门和人们对美好人居环境需求的背景下,通过划定城市生态保护红线以控制和维持现有重要功能生态空间,保护和改善高敏感生态空间,维护区域生态安全显得尤为重要。基于对澳门陆域生态系统调查,结合城市和自然资源特征,从生态系统服务功能、生态系统敏感性、生物多样性分布以及现有生态保护区四个方面构建了城市生态保护红线划定方法框架,选取并评估水源涵养、雨洪调节、热岛调节、土壤保持、海岸带防护五类调节服务和生态系统服务中的休闲游憩的空间格局,水土流失敏感性和海岸带风暴潮敏感性两种生态敏感性的分布,并综合澳门具有保育价值生物的栖息地分布和现有保护区范围进行了城市生态保护红线的划定。研究结果显示,澳门城市生态保护红线区域总面积6.71km2,占研究区面积的19.79%,覆盖了44%的生态空间、12.4%的海岸线、所有的重要物种栖息地及三分之一的古树名木。依照此生态保护红线研究进一步提出针对各类红线地块的保护和管理措施。研究提出的城市生态保护红线划定思路,可以为其他城市的重要生态空间保护、修复与管理提供参考。 相似文献
28.
“两山”理念提升了我国各级各地政府对生态价值的认识和重视,自然资本核算在全球学界研究及应用已进入新的阶段。如何开展常态化的核算与应用,如何将科研分析转化为管理制度,成为该领域新的研究命题。深圳积极响应中央政府要求,开展生态系统服务价值核算,服务生态治理,在全国(乃至全球)率先制定了第一个政府生态系统生产总值(GEP)核算制度体系。介绍了深圳GEP核算制度体系的建设过程,描述了深圳GEP核算的主要特点,以及"十三五"期间(2016-2020年)深圳GEP试算的结果,讨论了深圳GEP在城市治理方面的应用路径。 相似文献
29.
快速城市化加快了城市生态系统格局的改变,导致生态系统服务价值下降,对城市可持续发展造成阻碍。为了探究何种城市发展模式能够创造更高的生态系统服务价值,以深圳为案例,利用2010年、2015年和2020年生态系统类型数据,设置经济、惯性和生态3种不同的发展模式,并使用CA-Markov模型对2025年深圳市各类生态系统变化进行预测。在此基础上创新性地核算了不同模式下的关键生态系统服务价值。结果显示:(1)2015年到2020年,各类生态系统呈现不同变化趋势,人类聚落生态系统快速增长,对各类自然生态系统造成侵占,城区绿地呈现自然减少人工增加趋势。(2)2025年3种发展模式对生态系统类型变化影响显著,惯性发展模式下人类聚落、城区绿地出现扩张,经济发展模式下进一步增长,自然生态系统面积显著减少,生态发展模式下自然生态系统面积得到恢复。(3)3种模式下的生态系统服务价值变化差异显著,惯性和经济发展模式下,生态系统服务价值显著下降,分别较2020年下降2.67%和5.25%。生态发展模式下,生态系统服务价值提高,较经济发展模式提升5.5%,3种模式生态系统调节服务总价值差最高达到38.1亿元。综合来看,未来的发展模式应当选择以生态保护为优先的发展模式,通过制定有效的生态空间保护措施如生态保护红线划定、城市潜在开发区调整,实施生态工程等提高城市生态空间面积和质量,维持和提高生态系统服务价值,实现经济发展与生态保护的协调并行。 相似文献
30.
Ying Liang Qi Lu Wei Li Dapeng Zhang Fanglin Zhang Qingping Zou Lu Chen Ying Tong Mengxing Liu Shaoxuan Wang Wenxuan Li Xiaoguang Ren Peng Xu Zhicong Yang Shihua Dong Baolong Zhang Yanni Huang Daqiang Li Hailin Wang Wenqiang Yu 《Nucleic acids research》2021,49(15):8556
Dysfunction of Tumour Suppressor Genes (TSGs) is a common feature in carcinogenesis. Epigenetic abnormalities including DNA hypermethylation or aberrant histone modifications in promoter regions have been described for interpreting TSG inactivation. However, in many instances, how TSGs are silenced in tumours are largely unknown. Given that miRNA with low expression in tumours is another recognized signature, we hypothesize that low expression of miRNA may reduce the activity of TSG related enhancers and further lead to inactivation of TSG during cancer development. Here, we reported that low expression of miRNA in cancer as a recognized signature leads to loss of function of TSGs in breast cancer. In 157 paired breast cancer and adjacent normal samples, tumour suppressor gene GPER1 and miR-339 are both downregulated in Luminal A/B and Triple Negative Breast Cancer subtypes. Mechanistic investigations revealed that miR-339 upregulates GPER1 expression in breast cancer cells by switching on the GPER1 enhancer, which can be blocked by enhancer deletion through the CRISPR/Cas9 system. Collectively, our findings reveal novel mechanistic insights into TSG dysfunction in cancer development, and provide evidence that reactivation of TSG by enhancer switching may be a promising alternative strategy for clinical breast cancer treatment. 相似文献