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11.
[目的]对长三角沿江城市群生态—经济—社会系统可持续发展态势进行研究,为该区域生态经济可持续发展提供科学支持。[方法]基于能值理论构建评价指标和评价体系,分析长三角沿江城市群生态—经济—社会系统的可持续发展态势。[结果] 2017年长三角沿江城市群中29%的城市资源过度开发,外部依赖性强;53%的城市环境负载率低,29.4%的城市环境负载率高;11.7%的城市废弃物循环再生能力低;47%的城市能值交换率低,经济竞争力强;35%的城市能值货币率高,经济产出效率低。上海、苏州单位面积能值密度高,23.5%的城市较低;29.4%的城市人均能值福利低;17.6%的城市人口负载率高;41.2%的沿江城市呈可持续发展态势,58.8%的城市呈过度发展态势。[结论] 2017年沿江城市群自给能力、环境压力、生态质量呈现上游城市强、小、优向中游基本协调,下游弱、高、差的渐变态势。上海、苏南城市经济竞争力强,但产出效率低;苏中、皖中地区除省会城市外其他城市竞争力弱;皖南城市经济发展滞后且呈沿江单边孤立发展态势。上海、苏南城市社会可持续发展优,形成人才、资源强吸引同时存在用地短缺问题;苏中城市较均衡并形成弱吸引;除合肥市、铜陵市外,皖中、皖南其他城市发展滞后,缺乏有效吸引。沿江城市群整体可持续发展态势严峻。  相似文献   
12.
【目的】探讨不同灌水下限设施土壤CO2排放特征及其影响因素,为调控设施土壤水分和碳排放提供理论依据。【方法】在番茄生育期内采用LI-8100A土壤碳通量自动测定仪观测不同灌水下限[20 kPa(D20)、30 kPa(D30)、40 kPa(D40)]下的土壤CO2排放速率,并分析其影响因素。【结果】在番茄生育期内,不同灌水下限设施土壤CO2排放速率变化趋势基本一致,D20处理最高,平均速率为2.759μmol/(m2·s),其次是D30处理,为2.601μmol/(m2·s),D40处理最低,为2.559μmol/(m2·s)。在土壤CO2累积排放量方面,D20处理显著高于其他2个处理,而D30和D40处理之间无显著差异。就单因素模型而言,不同灌水下限处理的土壤CO2排放速率与15 cm土壤温度呈指数回归关系,且均达显著水平(P<0.05);不同灌水下限处理的土壤CO2排放速率与15 cm土壤含水率均呈显著二次回归关系(P<0.05);与单因素模型相比,土壤温度和土壤含水率的双因素复合模型(68.5%~83.8%)可以更好地解释土壤CO2排放的变化。土壤温度敏感系数Q10值在1.442~1.498之间,其中D20处理最敏感,D40处理最不敏感。相关分析结果表明,土壤CO2累积排放量与0~20 cm土层土壤有机质量、pH值、全氮量、速效磷量、速效钾量、碱解氮量和微生物量碳呈显著相关关系。采用PCA分析提取出的2个主成分累积贡献率为85.79%。【结论】灌水下限影响设施土壤CO2的排放,其中D20处理促进了设施土壤CO2的排放。  相似文献   
13.
拉丁美洲和加勒比地区是世界主要的竹资源分布区,以瓜多竹为代表的560多竹种资源占全球竹种的33%,其中巴西、哥伦比亚、秘鲁、厄瓜多尔、墨西哥等国竹林面积和竹种数量位居该地区前列。与亚洲相比,拉丁美洲和加勒比地区现代竹产业发展起步较晚,规模和效益有限。面向未来,该区竹资源主要分布国家的政府正在制定和实施相关政策和战略,助力竹区发展经济、缓解贫困和保护环境。  相似文献   
14.
AIM: To investigate the effect of salvianolate on oxidative damage induced by hydrogen peroxide in human endothelial EA.hy926 cells.METHODS: EA.hy926 cells were cultured in vitro and divided into the following groups:control group, damage group, and anti-damage groups (salvianolate+damage groups). The cell viability was measured by CCK-8 assay. The migration ability of the EA.hy926 cells was detected by Transwell assay. The content of nitric oxide (NO) in the culture supernatant of the EA.hy926 cells was examined. The levels of vascular endothelial growth factor (VEGF) were detected by ELISA. The apoptosis,mitochondrial membrane potential and intracellular superoxide anion content of the EA.hy926 cells were analyzed by flow cytometry. The protein levels of caspase-3, cleaved caspase-3, Bcl-2, Bax, NF-κB and p53 were determined by Western blot. RESULTS: Compared with damage group, the viability of EA.hy926 cells pretreated with salvianolate at different concentrations was significantly increased (P<0.05). The apoptotic rate was significantly decreased (P<0.05). Savianolate enhanced the migration ability of the cells. The levels of VEGF, NO and mitochondrial transmembrane potential were increased (P<0.05), and the intracellular ROS level was significantly decreased (P<0.05). The protein levels of NF-κB, p53, Bax and cleaved caspase-3 were significantly decreased, and the protein level of Bcl-2 was markedly increased(P<0.05). CONCLUSION: Savianolate reduces the damage of EA.hy926 cells by hydrogen peroxide exposure, and its mechanism may be related to the blocking of NF-κB signaling pathway.  相似文献   
15.
【背景】山羊第一卵泡波中的优势卵泡(dominant follicles, DF)和从属卵泡(subordinate follicles, SF)是整个卵泡发育过程中最为关键的两个阶段。随着卵泡的进一步发育,最终DF可能发育成为成熟卵泡,直到排卵;SF将走向闭锁,其中颗粒细胞的凋亡是导致卵泡发生闭锁的关键因素。然而目前对促进卵泡的优势化或导致其闭锁的分子机理尚不清楚。【目的】通过对山羊第一卵泡波中DF和SF颗粒细胞进行高通量测序,旨在筛选影响卵泡发育的关键基因,为深入探究卵泡发育的调控机制提供理论依据。【方法】选取10只1岁龄健康的贵州白山羊分别注射前列腺素F,使其同期发情,此后每天用B超检测并记录卵泡的生长情况,发情3 d后,统一屠宰并采集第一卵泡波中DF (直径4.5—6 mm)与SF (直径3 —4.5 mm),分别分离其中的颗粒细胞,提取总RNA、构建文库后通过Illumina Hiseq 2500平台进行测序。利用FastQC对测序产出raw reads进行质量评估并经过过滤后,获得品质较高的clean reads;使用Trinity对得到的clean reads进行重新组装,从而获得unigenes;使用CLC Genomics Workbench将unigenes与山羊RefSeq数据库进行比对获得mRNA;使用DESeq2 软件对获得的mRNA进行差异表达分析;分别采用goseq和kobas软件对得到的差异表达基因进行GO分析及KEGG信号通路分析;最终通过qRT-PCR对筛选出的可能影响卵泡发育的关键基因进行验证。【结果】分别对测序得到的raw reads进行过滤后,在DF颗粒细胞中获得43 217 934条clean reads,占raw reads的比例为95.19%;SF颗粒细胞中获得40 766 348条clean reads,占raw reads的比例为95.35%。将得到的unigenes与山羊的RefSeq 数据库进行比对后,共得到33 896条带有注释的转录本,再通过设定FPKM>1, q value<0.05,共在两种卵泡颗粒细胞中获得13 644个基因。设定参数:FPKM≥1,SF-FPKM/DF-FPKM>1,P<0.05,获得695个差异表达mRNA,其中233个在SF颗粒细胞中表达显著上调,462个表达显著下调;对所获得695个差异表达mRNA进行GO功能富集分析,共分为三大类42组:其中生物学过程占47.6%,细胞组分占47.6%,分子功能占4.8%;KEGG信号通路分析,发现20条通路,其中与核糖体通路相关的基因富集最为显著。通过在Genecard中进行功能分析后,筛选6个可能与山羊卵泡发育密切相关的基因,其中PRLRPTX3RGN在SF颗粒细胞中表现为上调;DKK3ALDH1A2RARRES1则表现为下调。qRT-PCR显示PRLRRGNDKK3ALDH1A2RARRES1的表达趋势与高通量测序结果一致,且RGN在从属卵泡颗粒细胞中的表达量极显著地高于优势卵泡(P<0.01);DKK3ALDH1A2RARRES1在优势卵泡颗粒细胞中的表达量极显著地高于从属卵泡(P<0.01)。【结论】DKK3ALDH1A2RARRES1RGN在优势卵泡和从属卵泡中表达量存在极显著差异,推测在山羊卵泡发育过程中可能促进卵泡的优势化或导致闭锁,对深入探究卵泡发育的调控机制具有重要意义。  相似文献   
16.
为探索母羊因素对哺乳期云上黑山羊羔羊生长发育的影响,根据母羊体重、胎次分别选取云上黑山羊初生羔羊90只和120只,公、母各半,从出生开始直至90日龄断奶,每10天进行1次体重测定,进行生长发育分析。结果表明:(1)母羊产后体重对羔羊初生重、哺乳期体重具有显著影响(P<0.05)。母羔中,38~45 kg母羊组和48~62 kg母羊组的羔羊初生重、平均日增重均显著高于28~35 kg母羊组(P<0.05)。公羔中,38~45 kg母羊组的羔羊初生重显著高于其他两组羔羊(P<0.05),48~62 kg母羊组其羔羊平均日增重显著高于其他两组羔羊(P<0.05)。(2)母羊胎次对母羔初生重没有显著影响,但对母羔哺乳期体重均有显著影响(P<0.05),母羔中,3胎、4胎母羊组的羔羊平均日增重均显著高于1胎和2胎母羊组;母羊胎次对公羔的影响不显著。说明母羊产后体重显著影响羔羊胎儿期和哺乳期的生长发育,合适的母羊体重可以为羔羊提供充足的营养;母羊胎次仅对哺乳期母羔具有显著影响,母羊的母性行为随胎次的增加而完善。  相似文献   
17.
AIM: To investigate the effects of astragaloside IV (AS-IV) on chemokine receptor 4 (CXCR4) and stromal cell-derived factor 1α (SDF-1α) in endothelial progenitor cells (EPCs) and its mechanism. METHODS: Rat bone marrow-derived EPCs were cultured in vitro. The proliferation, adhesion, migration, apoptosis and tube formation capacity of EPCs treated with AS-IV and AMD3100, a specific blocker of CXCR4, were observed. The effects of AS-IV on the expression of SDF-1α/CXCR4 at mRNA and protein levels and the protein level of p-CXCR4 in the EPCs were determined. RESULTS: AS-IV significantly enhanced the proliferation, adhesion, migration and tube formation abilities of EPCs, reduced the apoptosis of EPCs, and up-regulated the mRNA and protein expression of SDF-1α and CXCR4 and the p-CXCR4 protein level in the EPCs. On the other hand, AMD3100 blocked the up-regulating effect of AS-IV on the mRNA and protein expression of CXCR4 and the p-CXCR4 protein level in the EPCs, but did not affect the effect of AS-IV on the expression of SDF-1α. CONCLUSION: AS-IV might enhance the biological function of EPCs by regulating the expression of SDF-1α/CXCR in EPCs.  相似文献   
18.
19.
AIM To investigate the effects of different components of Gynostemma pentaphyllum [gypenosides (Gps), gypenoside XLIX (GpXLIX) and ginsenoside Rb3 (GRb3)] on mitochondrial energy metabolism-related proteins in endothelial cells induced by oxidized low-density lipoprotein (ox-LDL). METHODS EA.hy926 cells were divided into control group, model group, Gps group, GpXLIX group and GRb3 group. The cells in control group were cultured only in DMEM complete medium. The cells in model group were treated with 100 mg/L ox-LDL for 48 h. The cells in Gps group, GpXLIX group and GRb3 group were treated with 100 mg/L ox-LDL for 24 h, and then treated with Gps, GpXLIX and GRb3 at 100 mg/L for another 24 h, respectively. The ATP content in each group was detected by ELISA. The expression levels of mitochondrial energy metabolism-related proteins, cytochrome C oxidase subunit 5a (Cox5a), NADH:ubiquinone oxidoreductase core subunit S1 (Ndufs1), ATP synthase F1 subunit alpha (ATP5a) and cytochrome C (Cyt C), were determined by Wes automatic Western blot quantitative analysis system and Western blot. RESULTS Compared with control group, the ATP content in model group was decreased (P<0.01). After drug intervention, the ATP content increased to different degrees in Gps group, GpXLIX group and GRb3 group (P<0.01). The results of Wes automatic Western blot quantitative analysis system were consistent with those of Western blot. These results showed that compared with control group, the protein expression of Cox5a, Ndufs1 and ATP5a in model group was decreased, and the protein expression of Cyt C was increased (P<0.01). After intervention, the protein expression of Cox5a, Ndufs1 and ATP5a was increased and the protein expression of Cyt C was decreased in Gps group, GpXLIX group and GRb3 group (P<0.05 or P<0.01). Among them, the effect of Gps on the protein expression of Cox5a, Ndufs1 and Cyt C was significantly stronger than those of the 2 monomer components, and the effect of GRb3 was found to be superior in the 2 monomer components. The effect of GpXLIX on ATP5a protein was superior to the other 2 components. CONCLUSION Gynostemma total saponins and related active ingredients protect ox-LDL-induced endothelial cells by affecting mitochondrial energy metabolism-related proteins, thereby preventing and treating atherosclerosis.  相似文献   
20.
AIMTo investigate the role of soluble Klotho protein in THP-1-derived foam cell formation. METHODSTHP-1 monocytes were induced into macrophages by treatment with 160 nmol/L phorbol myristate acetate for 48 h, and then were divided into 6 groups: negative control group (THP-1-derived macrophages), positive control group [THP-1-derived foam cells induced by oxidized low-density lipoprotein (ox-LDL) for 48 h], and 25, 50, 100 and 200 μg/L soluble Klotho protein groups (THP-1-derived macrophages pretreated with soluble Klotho protein at the indicat?ed concentraions for 2 h and then induced by ox-LDL for 48 h). Lipid droplets in cytoplasm were observed by oil red O staining. The cholesterol outflow rate was detected by scintillation counting technique. The content of intracellular total cholesterol, free cholesterol and cholesterol ester was detected by enzyme fluorescence analysis. The expression of acyl-coenzyme A:cholesterol acyltransferase 1 (ACAT1) and ATP-binding cassette transport?er A1 (ABCA1) at mRNA and protein levels was determined by RT-qPCR and Western blot, respectively. RESULTSOil red O staining and lipid mass quantification showed that THP-1-derived foam cell formation was dose-dependently suppressed by soluble Klotho protein. The cholesterol efflux rate of THP-1-derived foam cells was increased by soluble Klotho protein in a dose-dependent manner (P<0.05). In addition, soluble Klotho protein decreased the expression of ACAT1 and increased the expression of ABCA1 in a dose-dependent manner (P<0.05). CONCLUSION The soluble Klotho protein inhibits THP-1-derived foam cell formation in a dose-dependent manner by down-regulating the expression of ACAT1 and up-regulating the expression of ABCA1.  相似文献   
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