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Biogeochemistry of sedimentary organic matter in the Yongjiang River estuary in the southern part of Hangzhou Bay,China,since the Late Pleistocene
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作者 Dongqin HUANG Xiaolong LI +6 位作者 Zilong LI Pei Sun LOH Jianxiong HU Jianfang CHEN Yuan-Pin CHANG Chin-Wen YANG qin gao 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期772-786,共15页
A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare e... A sediment core(YJK19-02)collected from the southern outlet of Hangzhou Bay near the Yongjiang River estuary in East China was analyzed for grain size,lignin,bulk elemental composition,stable carbon isotope,and rare earth elements(REEs)to determine the sources and diagenesis of sedimentary organic matter(OM)of the estuary and adjacent areas since the Late Pleistocene.δ^(13)C values(-24.80‰–-23.60‰),total organic carbon/total nitrogen(TOC/TN)molar ratios(8.00–12.14),and light rare earth element/heavy rare earth element ratios(LREE/HREE=8.34–8.91)revealed the predominance of terrestrial sources of OM,mainly from the Changjiang(Yangtze)River.The lignin parameters of syringyl/vanillyl(S/V=0.20–0.73)and cinnamyl/vanillyl(C/V=0.03–0.19)ratios indicate the predominance of nonwoody angiosperms,and the vanillic acid/vanillin ratios[(Ad/Al)_(V)=0.32–1.57]indicate medium to high degrees of lignin degradation.An increasing trend ofΛ(total lignin in mg/100-mg OC)values from ca.14500 a BP to ca.11000 a BP reflected the increase in temperature during the Late Pleistocene.However,a time lag effect of temperature on vegetation abundance was also revealed.The relatively higher and stableΛvalues correspond to the higher temperature during the mid-Holocene from ca.8500 a BP to ca.4500 a BP.Λvalues decreased from ca.4000 a BP to the present,corresponding to historical temperature fluctuations during this time.Our results show that the vegetation abundance in the Yongjiang River Basin since the Late Pleistocene was related to the temperature fluctuation duo to climate change. 展开更多
关键词 Yongjiang River estuary sedimentary organic matter LIGNIN environmental change Late Pleistocene
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Effects of counter-current driven by electron cyclotron waves on neoclassical tearing mode suppression
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作者 高钦 郑平卫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期501-509,共9页
Through theoretical analysis,we construct a physical model that includes the influence of counter-external driven current opposite to the plasma current direction in the neoclassical tearing mode(NTM).The equation is ... Through theoretical analysis,we construct a physical model that includes the influence of counter-external driven current opposite to the plasma current direction in the neoclassical tearing mode(NTM).The equation is used with this model to obtain the modified Rutherford equation with co-current and counter-current contributions.Consistent with the reported experimental results,numerical simulations have shown that the localized counter external current can only partially suppress NTM when it is far from the resonant magnetic surface.Under some circumstances,the Ohkawa mechanism dominated current drive(OKCD)by electron cyclotron waves can concurrently create both co-current and counter-current.In this instance,the minimal electron cyclotron wave power that suppresses a particular NTM was calculated by the Rutherford equation.The result is marginally less than when taking co-current alone into consideration.As a result,to suppress NTM using OKCD,one only needs to align the co-current with a greater OKCD peak well with the resonant magnetic surface.The effect of its lower counter-current does not need to be considered because the location of the counter-current deviates greatly from the resonant magnetic surface. 展开更多
关键词 driven current neoclassical tearing mode modified Rutherford equation electron cyclotron waves
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白桦脂醇对宫颈癌小鼠自然杀伤细胞杀伤力及淋巴细胞增殖活性的影响 被引量:3
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作者 罗芳 高琴 费志医 《中国现代医学杂志》 CAS 北大核心 2022年第6期6-11,共6页
目的探究白桦脂醇对宫颈癌小鼠自然杀伤(NK)细胞杀伤力及淋巴细胞增殖活性的影响。方法通过皮下注射人宫颈癌HeLa细胞复制宫颈癌小鼠模型。将45只模型小鼠随机分为模型组、白桦脂醇组和白桦脂醇+SB203580组,每组15只。另取15只未做处理... 目的探究白桦脂醇对宫颈癌小鼠自然杀伤(NK)细胞杀伤力及淋巴细胞增殖活性的影响。方法通过皮下注射人宫颈癌HeLa细胞复制宫颈癌小鼠模型。将45只模型小鼠随机分为模型组、白桦脂醇组和白桦脂醇+SB203580组,每组15只。另取15只未做处理的小鼠作为对照组。白桦脂醇组和白桦脂醇+SB203580组白桦脂醇灌胃干预(100 mg/kg)。白桦脂醇+SB203580组通过腹腔注射SB203580(50 ng/kg)抑制p38通路。采用免疫组织化学染色检测细胞增殖。比较各组p38蛋白、NK细胞杀伤力及淋巴细胞增殖活性。结果白桦脂醇组和白桦脂醇+SB203580组肿瘤体积和质量小于模型组(P<0.05),并且白桦脂醇+SB203580组肿瘤体积和质量小于白桦脂醇组(P<0.05)。白桦脂醇组和白桦脂醇+SB203580组免疫组织化学染色评分、p38蛋白相对表达量低于模型组(P<0.05),并且白桦脂醇+SB203580组免疫组织化学染色评分、p38蛋白相对表达量低于白桦脂醇组(P<0.05)。白桦脂醇组和白桦脂醇+SB203580组脾脏指数、NK细胞杀伤力、淋巴细胞增殖活性高于模型组(P<0.05),并且白桦脂醇+SB203580组脾脏指数、NK细胞杀伤力、淋巴细胞增殖活性高于白桦脂醇组(P<0.05)。结论白桦脂醇通过抑制p38通路抑制宫颈癌细胞增殖,并提高NK细胞杀伤力和淋巴细胞增殖活性。 展开更多
关键词 宫颈癌 白桦脂醇 P38通路 免疫 自然杀伤细胞 小鼠
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半夏泻心汤加减配合中药保留灌肠治疗溃疡性结肠炎疗效观察 被引量:5
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作者 覃高 刘春强 《智慧健康》 2020年第13期147-148,共2页
目的对溃疡性结肠炎患者接受半夏泻心汤加减配合中药保留灌肠的临床疗效进行系统研究,以证实治疗有效性。方法选择本院2017年8月至2019年8月收治的100例溃疡性结肠炎患者作为实验对象,数字奇偶法分组后探究各组治疗效果。对照组(50例):... 目的对溃疡性结肠炎患者接受半夏泻心汤加减配合中药保留灌肠的临床疗效进行系统研究,以证实治疗有效性。方法选择本院2017年8月至2019年8月收治的100例溃疡性结肠炎患者作为实验对象,数字奇偶法分组后探究各组治疗效果。对照组(50例):应用常规治疗;实验组(50例):应用半夏泻心汤加减配合中药保留灌肠治疗。对比两组患者临床治疗效果、各项临床症状积分。结果实验组临床治疗总有效率比对照组高,经比较,差异性显著(P<0.05);实验组腹痛积分、腹泻积分、黏液脓血便积分,均比对照组低,组间对比差异性显著(P<0.05)。结论半夏泻心汤加减配合中药保留灌肠治疗溃疡性结肠炎患者,不仅能够使病情得到有效控制,而且使患者临床症状明显改善,加快病情康复速度。 展开更多
关键词 半夏泻心汤加减 中药保留灌肠 溃疡性结肠炎 疗效
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Caspase-1 inhibition attenuates activation of BV2 microglia induced by LPS-treated RAW264.7 macrophages 被引量:5
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作者 Yang Pan Bo Shen +4 位作者 qin gao Jun Zhu Jingde Dong Li Zhang Yingdong Zhang 《The Journal of Biomedical Research》 CAS CSCD 2016年第3期225-233,共9页
Neuroinflammation has been recognized as a factor in the pathogenesis ofneurodegenerative diseases. Emerging evidence suggests that peripheral inflammation, besides neuroinflammation, functions as a modulator of disea... Neuroinflammation has been recognized as a factor in the pathogenesis ofneurodegenerative diseases. Emerging evidence suggests that peripheral inflammation, besides neuroinflammation, functions as a modulator of disease progression and neuropathology in several neurodegenerative diseases. However, detailed correlations among pe- ripheral inflammation, neuroinflammation and neurodegeneration remain unknown. In the present study, we pre- pared a peripheral inflammation model with lipopolysaccharides (LPS)-stimulated RAW264.7 macrophages to ex- plore its activation on BV2 microglia. We found that LPS induced the production of IL-1β, IL-6 and TNF-a in the culture medium of RAW264.7 macrophages. We further showed that LPS plus ATP activated inflammasome, evidenced by the upregulation of caspase-1 and IL-113, which was suppressed by ZYVAD, a caspase-1 inhibitor. Furthermore, the conditioned medium obtained from LPS-treated RAW264.7 macrophages activated BV2 micro- glia, stimulating the release of IL-1β, IL-6 and TNF-a from BV2 cells. ZYVAD pretreatment markedly suppressed BV2 microglia activation induced by RAW264.7 cells conditioned medium. Taken together, our study indicates that macrophage-mediated peripheral inflammation subsequently evokes neuroinflammation and may aggravate neural damage. Inflammasome and caspase- 1 may be potential targets for modulating systemic inflammatory responses in neurodegenerative diseases. 展开更多
关键词 peripheral inflammation NEUROINFLAMMATION neurodegenerative diseases NLRP3 inflammasome CASPASE-1
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A Brief Study on pH, Exchangeable Ca<sup>2+</sup>and Mg<sup>2+</sup>in Farmlands under Tobacco-Rice Rotation in Xuancheng City of South Anhui 被引量:5
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作者 Anqi Wang Ka Lin +9 位作者 Chengxin Ma qin gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue Chaolong Zu Chaoqiang Jiang Jia Shen Decheng Li 《Agricultural Sciences》 2018年第4期480-488,共9页
pH, exchangeable Ca2+ and Mg2+ of soil can influence the yield and quality of flue-cured tobacco. Xuancheng city is the dominant tobacco-planting region in Anhui province since 2008. A general soil survey was conducte... pH, exchangeable Ca2+ and Mg2+ of soil can influence the yield and quality of flue-cured tobacco. Xuancheng city is the dominant tobacco-planting region in Anhui province since 2008. A general soil survey was conducted in Xuancheng city to understand the current situations of pH, exchangeable Ca2+ and Mg2+ of farmlands under tobacco-rice rotation and to decide whether continuous applying dolomite powders to abate soil acidification. In total 124 topsoil samples (0-20 cm) were collected from the typical farmlands and soil pH, exchangeable Ca2+ and Mg2+ were measured. The results showed that soil pH and Ca2+ and Mg2+ in Xuancheng city were generally in the suitable grades, pH ranged from 4.56 to 8.42 with an average of 5.87, exchangeable Ca2+ ranged from 1.01 cmol(1/2Ca2+) kg-1 to 100.55 cmol(1/2Ca2+) kg-1 with an average of 11.07 cmol(1/2Ca2+) kg-1, and exchangeable Mg2+ ranged from 0.14 cmol(1/2Mg2+) kg-1 to 2.86 cmol(1/2Mg2+) kg-1 with an average of 0.81 cmol(1/2Mg2+) kg-1, all spanned from the low grades to the high grades. To the whole Xuancheng city, 37.10%, 62.10% and 72.58% of the surveyed farmlands were in the low grades of pH, exchangeable Ca2+ and Mg2+, respectively, while 52.42%, 25.00% and 20.97% of the farmlands were in the suitable grades, respectively. pH had an extremely significantly positive Napierian logarithm correlation with exchangeable Ca2+ and an extremely significantly positive power correlation with exchangeable Mg2+. In total about 338.2 kg·hm-2 of Ca2+ and 202.4 kg·hm-2 of Mg2+ are annually input into the farmlands, while about 110.4 kg·hm-2 of Ca2+ and 7.4 kg·hm-2 of Mg2+ are annually moved out from the farmlands, exchangeable Ca2+ and Mg2+ were annually increased by 225.2 kg·hm-2 and 187.6 kg·hm-2 in the farmlands, respectively. It is necessary to monitor the farmlands dynamically in order to decide whether continuous applying dolomite powders which should be dependent upon the specific conditions of individual farmlands. 展开更多
关键词 PH Exchangeable Ca2+ and Mg2+ DOLOMITE Powders Farmlands Tobacco-Rice Rotation Xuancheng CITY
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Inducible expression of endomorphins in murine dendritic cells 被引量:1
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作者 Xiaohuai Yang Hui Xia +4 位作者 Yong Chen Xiaofen Liu Cheng Zhou qin gao Zhenghong Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第35期2811-2817,共7页
Bone marrow precursor cells were extracted from C57BL/6J mice aged 7-8 weeks, and dendritic cells were purified using anti-CD1 lc (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluores... Bone marrow precursor cells were extracted from C57BL/6J mice aged 7-8 weeks, and dendritic cells were purified using anti-CD1 lc (a specific marker for dendritic cells) antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme Jmmunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [3H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of IJ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of iJ-opioid receptors. 展开更多
关键词 dendritic cells ENDOMORPHIN I J-receptor antigen-presenting cell nerve immunization neuralregeneration
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lncRNA-PCAT6通过调控miR-185/SIX1轴对肺癌A549细胞上皮间质转化及化疗敏感性的影响
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作者 王华丽 农开旭 +2 位作者 程守斌 秦篙 许振胜 《中国免疫学杂志》 CAS CSCD 北大核心 2022年第23期2840-2846,共7页
目的:探讨长链非编码RNA-PCAT6(lncRNA-PCAT6)对肺癌A549细胞上皮间质转化(EMT)和化疗敏感性的影响,以及对微小RNA-185(miR-185)/SIX1轴的调控作用。方法:取A549细胞,分为空白组、lncRNA-PCAT6低表达腺病毒(PCAT6-Si)组、不含lncRNA-PCA... 目的:探讨长链非编码RNA-PCAT6(lncRNA-PCAT6)对肺癌A549细胞上皮间质转化(EMT)和化疗敏感性的影响,以及对微小RNA-185(miR-185)/SIX1轴的调控作用。方法:取A549细胞,分为空白组、lncRNA-PCAT6低表达腺病毒(PCAT6-Si)组、不含lncRNA-PCAT6-Si的空病毒载体(eGFP-Si-1)组、miR-185低表达腺病毒(miR-185-Si)组、不含miR-185-Si的空病毒载体(eGFP-Si-2)组、PCAT6-Si与miR-185-Si共转染(PCAT6-Si+miR-185-Si)组。RT-qPCR法检测lncRNA-PCAT6、miR-185表达;Transwell法测定细胞侵袭、迁移能力;免疫荧光检测EMT标志物N-cadherin阳性表达;Western blot法测定SIX1、EMT标志蛋白E-cadherin、Vimentin及N-cadherin表达。取A549细胞系及其顺铂耐药细胞株A549/DDP,RT-qPCR及Western blot法检测lncRNA-PCAT6、miR-185表达。取A549/DDP转染PCAT6-Si与miR-185-Si,并分为A549组、A549/DDP组、PCAT6-Si组、miR-185-Si组、PCAT6-Si+miR-185-Si、eGFP-Si-1组、eGFP-Si-2组;RT-qPCR检测lncRNA-PCAT6、miR-185表达;CCK-8法检测各组细胞半数抑制浓度(IC50)及耐药指数(RI);Western blot法检测SIX1、耐药相关蛋白P-gp表达;裸鼠荷瘤试验验证PCAT6对A549/DDP细胞化疗敏感性的作用。双荧光素酶试验验证PCAT6与miR-185之间的靶向关系。结果:与A549细胞相比,A549/DDP细胞IC50及RI、lncRNA-PCAT6、SIX1及P-gp表达升高(P<0.05),miR-185表达降低(P<0.05)。敲低A549细胞中lncRNA-PCAT6表达后,miR-185表达升高,SIX1蛋白表达降低,细胞侵袭、迁移能力及EMT进程降低,IC50及RI降低、肿瘤体积减小,且各指标变化差异显著(P<0.05)。敲低miR-185可逆转lncRNA-PCAT6的上述作用。双荧光素酶报告试验证实lncRNAPCAT6与miR-185之间有靶向负调控作用。结论:肺癌A549细胞中lncRNA-PCAT6低表达可靶向上调miR-185,下调SIX1,抑制EMT进程,增强对DDP化疗的敏感性。 展开更多
关键词 长链非编码RNA-PCAT6 微小RNA-185 肺癌A549细胞 化疗敏感性
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Optimization of the Extraction Technology of Chlorogenic Acid from Sunflower Meal Using Response Surface Methodology 被引量:1
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作者 LIU Gang qin gao REN Xue 《Chinese Food Science》 2012年第2期1-4,7,共5页
[Objective]To optimize the ultrasonic-assisted extraction process of chlorogenic acid from sunflower meal.[Method]Based on the single-factor test,the extraction factors of ethanol concentration,extraction temperature ... [Objective]To optimize the ultrasonic-assisted extraction process of chlorogenic acid from sunflower meal.[Method]Based on the single-factor test,the extraction factors of ethanol concentration,extraction temperature and extraction time were optimized using the response surface methodology with the extraction rate of chlorogenic acid as the response value.[Result]The optimum extraction conditions of chlorogenic acid from sunflower meal were 57% of ethanol concentration,39 min of extraction time,53℃ of extraction temperature,100 W of ultrasonic power,1:14(g/ml)of solid-liquid ratio and one time of extraction.Under these conditions,the extraction rate of chlorogenic acid was 2.25%.[Conclusion]Ultrasonic assisted extraction method has high extraction rate but short time,the study provides a theoretical basis for the industrialized production of chlorogenic acid in sunflower meal. 展开更多
关键词 响应曲面法 提取工艺 工艺优化 绿原酸 葵花粕 超声波辅助提取 提取时间 乙醇浓度
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Contents and Changes of Potassium in Plough Layers of Xuancheng, South Anhui Province
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作者 Ka Lin Decheng Li +9 位作者 Xiaodong Song Chaolong Zu Chaoqiang Jiang Jia Shen Chengxin Ma qin gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue 《Agricultural Sciences》 2017年第5期348-355,共8页
Xuancheng City is the dominant tobacco-planting area of Anhui province due to the high quality of the tobacco leaves. However, the potassium content in the tobacco leaves shows a gradual decreasing trend in recent yea... Xuancheng City is the dominant tobacco-planting area of Anhui province due to the high quality of the tobacco leaves. However, the potassium content in the tobacco leaves shows a gradual decreasing trend in recent years, which may be attributed partly to the possible low potassium content in topsoil of tobacco-planting farmland. Therefore, the content data in the year of 2005-2007 of rapidly available potassium (RA-K) of 7730 topsoil samples mainly under double rice rotation or wheat/rice-rice rotation at that time and the content data of slowly available potassium (SA-K) and RA-K of 124 typical topsoil samples in the year of 2015 under tobacco-rice rotation were used and compared in order to disclose the status of topsoil potassium and to provide a guidance for reasonable potassium fertilization in Xuancheng. The results showed that in 2005-2007 RA-K content ranged from 1 mg&#183kg-1 to 844 mg&#183kg-1 with an average of 68 mg&#183kg-1, and 82.7% of topsoil samples were insufficient in RA-K (-1). Comparatively in 2015 SA-K content ranged from 230 mg&#183kg-1 to 1340 mg&#183kg-1 with an average of 595 mg&#183kg-1, and 13.7% of soil samples were insufficient in SA-K (-1);RA-K content ranged from 46 mg&#183kg-1 to 352 mg&#183kg-1 with an average of 134 mg&#183kg-1, and 25.8% of soil samples were insufficient in RA-K (-1). The above data show that RA-K content has increased gradually in farmland topsoil mainly due to fertilization since 1980s, particularly to farmland under tobacco-rice rotation, but insufficient RA-K in topsoil is still widely and serious for farmland under double rice rotation or wheat/rice-rice rotation. Under tobacco-rice rotation, RA-K insufficiency usually occurred in the farmlands which plant tobacco less than 3 years, indicating more potassium fertilizer should be applied. 展开更多
关键词 Rapidly Available POTASSIUM (RA-K) Slowly Available POTASSIUM (SA-K) TOPSOIL Tobacco-Rice ROTATION Xuancheng City
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Changes of NLRP1-ASC-Caspase-1 signaling pathways in peripheral blood monocytes from patients with atrial fibrillation
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作者 Fei-Yu Zhu qing-Mei Xu +5 位作者 Jian Zhu Yang Tang qin gao Bi Tang Pin-Fang Kang Hong-Ju Wang 《Journal of Hainan Medical University》 2021年第14期13-18,共6页
Objective:To detect the expression of(Peripheral blood mononuclear cells,PBMCs)NLRP3 signal pathway in peripheral blood monocytes of patients with chronic heart failure,and to explore the expression of NLRP3 signal pa... Objective:To detect the expression of(Peripheral blood mononuclear cells,PBMCs)NLRP3 signal pathway in peripheral blood monocytes of patients with chronic heart failure,and to explore the expression of NLRP3 signal pathway and its induced inflammatory response in PBMCs of patients with different types of chronic heart failure.Methods:patients with chronic heart failure(NYHAⅡ~Ⅳ),Ⅱ(nude 20),Ⅲ(nude 20)andⅣ(nude 20)admitted to our hospital from 2019 to 2020 were selected,and 20 normal subjects were selected as the control group.The peripheral venous blood of all subjects was collected,and the plasma and monocytes were extracted respectively.The monocytes were identified by magnetic beads sorting.The mRNA and protein expression levels of NLRP3,ASC and Caspase-1 in PBMCs were detected by real-time fluorescence quantitative polymerase chain reaction(qRT-PCR)and Western blot,and the level of interleukin-1β(IL-1β)in plasma was detected by enzyme-linked immunosorbent assay((ELISA)).Results:compared with the normal control group,the expression of NLRP3,ASC,Caspase-1 protein and mRNA in PBMCs of patients with gradeⅡ,ⅢandⅣincreased.Compared with patients with gradeⅡ,the expression of these indexes increased in patients with gradeⅢandⅣ.Compared with patients with gradeⅢ,the expression of these indexes increased in patients with gradeⅣ.Compared with the normal control group,the plasma levels of IL-1βin patients with gradeⅡ,ⅢandⅣwere higher than those in patients with gradeⅡ,ⅢandⅣ(P<0.05).The expression of these indexes in patients with gradeⅢandⅣwas higher than that in patients with gradeⅢ(P<0.05).Conclusion:the results suggest that NLRP3-ASC-Caspase-1 signal pathway may cause chronic inflammation in patients with heart failure and play a role in the progression of chronic heart failure. 展开更多
关键词 Chronic heart failure Peripheral blood monocytes NLRP3 ASC CASPASE-1
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Brief Study on Microelement Contents in Topsoils of Farmlands in Xuancheng, South Anhui
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作者 Anqi Wang Ka Lin +9 位作者 Chengxin Ma qin gao Qifa Zhu Xuejun Ji Guo Zhang Lin Xue Chaolong Zu Chaoqiang Jiang Jia Shen Decheng Li 《Agricultural Sciences》 2018年第6期718-728,共11页
The available contents of microelements in the topsoil can influence the yield and quality of flue-cured tobacco. Xuancheng is the dominant tobacco-planting region in Anhui province since 2008. In this paper, the tops... The available contents of microelements in the topsoil can influence the yield and quality of flue-cured tobacco. Xuancheng is the dominant tobacco-planting region in Anhui province since 2008. In this paper, the topsoil available Fe, Mn, Cu and Zn contents of 4197 farmlands mainly under rice-rice rotation and wheat-rice rotation in 2008 and of 124 typical farmlands under tobacco-rice rotation in 2015 in Xuancheng city were analyzed in order to disclose the changes and spatial distributions of these microelements and to instruct the reasonable application of the microelement fertilizers. The results showed that the topsoil average available contents in the farmlands under rice-rice rotation or wheat-rice rotation in 2008 were 105.9 mg·kg-1 for Fe, 19.6 mg·kg-1 for Mn, 4.5 mg·kg-1 for Cu, and 3.0 mg·kg-1 for Zn, respectively, increased by 33.14%, 64.29%, 51.11% and 36.67%, respectively, compared with those in the 2nd Soil Survey in 1980s, and the historic, once intensive and overall application of microelement fertilizers was attributed to the great increases. The topsoil average available contents in the farmlands under tobacco-rice rotation in 2015 were 31.1 mg·kg-1 for Fe, 9.8 mg·kg-1 for Mn, 2.1 mg·kg-1 for Cu, and 0.3 mg·kg-1 for Zn, respectively, decreased by 70.63%, 50.00%, 53.33% and 90.00%, respectively, compared with those of the farmlands under rice-rice rotation or wheat-rice rotation in 2008, and the net deficiencies in the input and output of microelements were attributed to the significant decreases in the topsoil microelements. It is necessary to monitor the farmlands under tobacco-rice rotation dynamically and in time in order to decide whether applying microelement fertilizers or not. 展开更多
关键词 Microelement Available CONTENT TOPSOIL of FARMLAND Xuancheng City
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基于Android的宠物服务平台构建研究
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作者 秦高 陈京生 +2 位作者 商滔 蔡小丹 吕兴琴 《无线互联科技》 2022年第9期56-58,共3页
宠物逐渐成为人类的生活伙伴,关于宠物的吃穿住行的宠物市场也随之发展起来,创建宠物健康信息管理系统显得异常重要。文章在分析市场上关于宠物服务问题的基础上,设计和开发了一款基于Android的宠物服务平台构建系统。该系统分为前端和... 宠物逐渐成为人类的生活伙伴,关于宠物的吃穿住行的宠物市场也随之发展起来,创建宠物健康信息管理系统显得异常重要。文章在分析市场上关于宠物服务问题的基础上,设计和开发了一款基于Android的宠物服务平台构建系统。该系统分为前端和后端两个部分,前端使用Android开发,主要实现用户交互界面功能,包括注册、咨询、宠物领养、用品购买等功能模块。后端使用Java开发,主要实现系统信息实施管理以及更新,后台连接MySQL数据库实现数据存储功能,可以通过服务端实时更改和发布对信息,实现对宠物服务的有效地管理。 展开更多
关键词 宠物收养 宠物服务 MYSQL 安卓
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A Study of Senior High School English Learners' Vocabulary Learning Strategies
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作者 qin gao 《Sino-US English Teaching》 2004年第8期45-49,共5页
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Co(OH)_(2)/CoN的界面空位协同作用促进碱性水分解
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作者 罗位 高琴 +6 位作者 马泽沔 马雪莹 蒋益敏 申伟 何荣幸 苏炜 李明 《Science China Materials》 SCIE EI CAS CSCD 2023年第6期2246-2256,共11页
开发高性能、稳定的双功能电催化剂是一个具有挑战性的课题.本工作基于界面工程和空位工程,通过电沉积成功构建了一种富含氧空位的异质结催化剂.所制备的催化剂V_(O)-Co(OH)_(2)/CoN在碱性电解质中具有良好的双功能催化活性和稳定性,在1... 开发高性能、稳定的双功能电催化剂是一个具有挑战性的课题.本工作基于界面工程和空位工程,通过电沉积成功构建了一种富含氧空位的异质结催化剂.所制备的催化剂V_(O)-Co(OH)_(2)/CoN在碱性电解质中具有良好的双功能催化活性和稳定性,在10 mA cm^(-2)条件下,析氢反应的过电位为52 mV,析氧反应的过电位为206 mV,且其全水分解电压仅为1.518 V.更重要的是,实验和密度泛函理论计算都证实了V_(O)-Co(OH)_(2)/CoN优异的双功能活性归因于异质界面和氧空位的协同催化.在异质界面附近,一个Co原子和一个氧空位共同形成一个活性Co空位对,通过改变反应路径协同促进水分解.氧空位不仅作为活性位点直接参与催化过程,还能有效调节电子密度,提高催化剂的导电性.本工作对于指导高性能催化剂的设计和深入了解催化机理具有重要意义. 展开更多
关键词 异质界面 析氢反应 催化机理 过电位 氧空位 电催化剂 催化过程 协同催化
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基于0-1测试的底吹搅拌混合过程混沌特性分析 被引量:2
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作者 高勤 肖清泰 +3 位作者 王仕博 李鹏 徐建新 王华 《过程工程学报》 CAS CSCD 北大核心 2018年第2期288-293,共6页
通过建立水力学模型研究底吹搅拌混合过程,利用流场可视化技术与直接成像技术获取实验图像数据,引入0-1测试方法,考察了喷枪布置方式(个数与角度)对混合过程混沌特性的影响.结果表明,基于颜色指示剂,利用数字图像处理手段可以近似估... 通过建立水力学模型研究底吹搅拌混合过程,利用流场可视化技术与直接成像技术获取实验图像数据,引入0-1测试方法,考察了喷枪布置方式(个数与角度)对混合过程混沌特性的影响.结果表明,基于颜色指示剂,利用数字图像处理手段可以近似估测混合过程的气含率,气含率演化规律符合实际工况运行特征;对各工况的气含率时间序列进行0-1测试,渐进增长率Kc中位数在一定程度上反映了不同混合过程的混沌强弱. 展开更多
关键词 底吹搅拌 喷枪布置 混沌特性 0-1测试 图像分析
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Reducing the oxidative stress mediates the cardioprotection of bicyclol against ischemia-reperfusion injury in rats 被引量:8
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作者 Jie CUI Zhi LI +7 位作者 Ling-bo QIAN qin gao Jue WANG Meng XUE Xiao-e LOU Iain C.BRUCE Qiang XIA Hui-ping WANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第6期487-495,共9页
Objective:To investigate the beneficial effect of bicyclol on rat hearts subjected to ischemia-reperfusion(IR) injuries and its possible mechanism.Methods:Male Sprague-Dawley rats were intragastrically administered wi... Objective:To investigate the beneficial effect of bicyclol on rat hearts subjected to ischemia-reperfusion(IR) injuries and its possible mechanism.Methods:Male Sprague-Dawley rats were intragastrically administered with bicyclol(25,50 or 100 mg/(kg·d)) for 3 d.Myocardial IR was produced by occlusion of the coronary artery for 1 h and reperfusion for 3 h.Left ventricular hemodynamics was continuously monitored.At the end of reperfusion,myocardial infarct was measured by 2,3,5-triphenyltetrazolium chloride(TTC) staining,and serum lactate dehydrogenase(LDH) level and myocardial superoxide dismutase(SOD) activity were determined by spectrophotometry.Isolated ventricular myocytes from adult rats were exposed to 60 min anoxia and 30 min reoxygenation to simulate IR injuries.After reperfusion,cell viability was determined with trypan blue;reactive oxygen species(ROS) and mitochondrial membrane potential of the cardiomyocytes were measured with the fluorescent probe.The mitochondrial permeability transition pore(mPTP) opening induced by Ca2+(200 μmol/L) was measured with the absorbance at 520 nm in the isolated myocardial mitochondria.Results:Low dose of bicyclol(25 mg/(kg·d)) had no significant improving effect on all cardiac parameters,whereas pretreatment with high bicyclol markedly reduced the myocardial infarct and improved the left ventricular contractility in the myocardium exposed to IR(P<0.05).Medium dose of bicyclol(50 mg/(kg·d)) markedly improved the myocardial contractility,left ventricular myocyte viability,and SOD activity,as well decreased infarct size,serum LDH level,ROS production,and mitochondrial membrane potential in rat myocardium exposed to IR.The reduction of ventricular myocyte viability in IR group was inhibited by pretreatment with 50 and 100 mg/(kg·d) bicyclol(P<0.05 vs.IR),but not by 25 mg/(kg·d) bicyclol.The opening of mPTP evoked by Ca2+ was significantly inhibited by medium bicyclol.Conclusions:Bicyclol exerts cardioprotection against IR injury,at least,via reducing oxidative stress and its subsequent mPTP opening. 展开更多
关键词 Ischemia-reperfusion injury CARDIOPROTECTION Oxidative stress Mitochondrial permeability transition pore BICYCLOL
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Social insurance for migrant workers in China:impact of the 2008 Labour Contract Law 被引量:6
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作者 qin gao Sui Yang Shi Li 《Economic and Political Studies》 2017年第3期285-304,共20页
Using the China Household Income Project(CHIP)2007,2008,and 2009 longitudinal migrant survey data,this article provides new evidence on the effects of China’s 2008 Labour Contract Law(LCL)on migrant workers’social i... Using the China Household Income Project(CHIP)2007,2008,and 2009 longitudinal migrant survey data,this article provides new evidence on the effects of China’s 2008 Labour Contract Law(LCL)on migrant workers’social insurance participation,including in pensions,work injury insurance,unemployment insurance,medical insurance,and the housing provident fund.We find consistently strong evidence that migrant workers’labour contract status was significantly associated with their participation in all five types of social insurance.In particular,having or gaining a long-term contract helped promote migrant workers’social insurance participation,while losing one such contract decreased their chance of social insurance participation.Using a difference-in-differences(DID)method and focussing on the panel sample,we find that the implementation of the LCL helped boost migrant workers’chance of social insurance participation consistently and significantly,especially for those who gained a long-term contract.These findings suggest that the LCL at least partly reached its intended policy goal of improving social protection for migrant workers,a disadvantaged group in the Chinese labour market.Future research should use longitudinal data and rigorous methods to track the long-term impact of this important law and help build a strong,unified social insurance system for all Chinese citizens. 展开更多
关键词 China Labour Contract Law migrant workers social insurance difference-indifferences
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Enhancement of Fe3O4/Au Composite Nanoparticles Catalyst in Oxidative Degradation of Methyl Orange Based on Synergistic Effect 被引量:2
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作者 qin gao Yan Xing +7 位作者 Mingli Peng Yongshuai Liu Zhiyi Luo Yanyan Jin Haiming Fan Kebin Li Chao Chen Yali Cui 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第9期1431-1436,共6页
Enhancement of Fe3O4/Au nanoparticles (Fe3O4/Au NPs) catalyst was observed in the oxidative degradation of methyl orange by employing H2O2 as oxidant. To evaluate the catalytic activity of Fe3O4/Au nanoparticles, di... Enhancement of Fe3O4/Au nanoparticles (Fe3O4/Au NPs) catalyst was observed in the oxidative degradation of methyl orange by employing H2O2 as oxidant. To evaluate the catalytic activity of Fe3O4/Au nanoparticles, different degradation conditions were investigated such as the amounts of catalyst, H2O2 concentration and pH value. Based on our data, methyl orange was degraded completely in a short time. The enhanced catalytic activity and increased oxidation rate constant may be ascribed to synergistic catalyst-activated decomposition of H2O2 to ,OH radical, which was one of the strong oxidizing species. Besides, Fe3O4/Au nanoparticles have exhibited satisfying recycle performance for potential industrial application. 展开更多
关键词 Fe3O4/Au nanoparticles methyl orange oxidative degradation hydroxyl radicals
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Zn and Ag Co-doped Anti-microbial TiO_2 Coatings on Ti by Micro-arc Oxidation 被引量:7
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作者 Lan Zhang qin gao Yong Han 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第9期919-924,共6页
Micro-porous TiO2 coatings co-doped with Zn^2+ and Ag nanoparticles were fabricated on Ti by microarc oxidation (MAO) for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the... Micro-porous TiO2 coatings co-doped with Zn^2+ and Ag nanoparticles were fabricated on Ti by microarc oxidation (MAO) for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the coating as a function of processing time were investigated. The microstructure of the 2 min treated coating was further observed by transmission electron microscopy to explore the coating formation mechanism. The amounts of Ag and Zn released from the 2 min treated coating were measured and the antibacterial properties of the coatings against Staphylococcus aureus (S. aureus) were also investigated. The obtained results showed that with prolonged MAO time, the contents of Ag and Zn on the coating surfaces increased. All the coatings were micro-porous with pore diameters of 1 -4μm; however, some pores were blocked by deposits on the 4 min treated coating. The 2 rain treated coating was composed of amorphous TiO2, anatase, futile, ZnO, Zn2TiO4 and homogenously distributed Ag nanoparticles. After immersion, Zn^2+, Ag^+, Ti^2+ and Ca^2+ were released from the coating and with the immersion time prolonged, the accumulated concentrations of these ions increased. After immersion for 36 weeks, the accumulated Zn2. and Ag^+ concentrations were 6.88 and 0.684 ppm, respectively, which are higher than the minimal inhibitory concentration but much lower than the cytotoxic concentration. Compared with polished Ti control, the coatings co-doped with Zn^2+ and Ag nanoparticles significantly inhibited the ad- hesions of S. uureus and reduced the amounts of planktonic bacteria in culture medium, indicating that the Zn and Ag co-doped TiO2 could be a bio-adaptable coating for long-lasting anti-microbial performance. 展开更多
关键词 Zn Ag nanoparticle Co-doped TiO2 Micro-arc oxidation Bio-adaptable
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