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Preparation of Sulphur-containing Aromatic Amines by Reduction of the Corresponding Aromatic Nitro Compounds with Hydrazine Hydrate over Iron Oxide Hydroxide Catalyst 被引量:1
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作者 Qi Xun SHI Rong Wen LU Zhu Xia ZHANG De Feng ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1045-1047,共3页
关键词 Iron oxide hydroxide catalyst hydrazine hydrate sulphur-containing aromatic nitro compounds reduction.
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Reduction of Sulphur-containing Aromatic Nitro Compounds with Hydrazine Hydrate over Iron(III) Oxide-MgO Catalyst 被引量:2
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作者 Qi Xun SHI Rong Wen LU Zhu Xia ZHANG De Feng ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期441-443,共3页
Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ... Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ) oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst. 展开更多
关键词 Iron(Ⅲ) oxide-MgO catalyst hydrazine hydrate sulphur-containing aromatic nitro compounds reduction.
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N<sup>ω</sup>-Nitro-N<sup>ω’</sup>-Substituted Guanidines: A Simple Class of Nitric Oxide Synthase Inhibitors
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作者 Christophe D. Guillon David D. Wisnoski +4 位作者 Jaya Saxena Ned D. Heindel Diane E. Heck Donald J. Wolff Jeffrey D. Laskin 《Modern Research in Inflammation》 2014年第2期48-58,共11页
A series of Nω-nitro-Nω’-substituted guanidines has been prepared as potential inhibitors of the human Nitric Oxide Synthase (NOS) isoforms. The reported utility of amino-guanidine and nitroarginine in iNOS inhibit... A series of Nω-nitro-Nω’-substituted guanidines has been prepared as potential inhibitors of the human Nitric Oxide Synthase (NOS) isoforms. The reported utility of amino-guanidine and nitroarginine in iNOS inhibition points to a potential similar utility for analogs of nitro-guanidine. The compound library was tested against the three isoforms of Nitric Oxide Synthase (eNOS, iNOS and nNOS). Several candidates showed excellent activity and good selectivity for nNOS. One particular compound even demonstrated good selectivity for iNOS. The potential usefulness of such selective inhibitors is discussed. 展开更多
关键词 nitro-Guanidines Nitric oxide SYNTHASE (NOS) ISOFORMS Selective Inhibitors
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Impact of Fenton and ozone on oxidation of wastewater containing nitroaromatic compounds 被引量:13
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作者 Fares Al Momani Mo’ayyad Shawaqfah +1 位作者 Ahmad Shawaqfeh Mohammad Al-Shannag 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第6期675-682,共8页
Fenton and ozone treatment was investigated at laboratory scale for the degradation of aqueous solutions of nitrobenzene (NB). Effects of reactants concentration (O3, H2O2, and Fe(Ⅱ)), temperature, and pH on NB... Fenton and ozone treatment was investigated at laboratory scale for the degradation of aqueous solutions of nitrobenzene (NB). Effects of reactants concentration (O3, H2O2, and Fe(Ⅱ)), temperature, and pH on NB degradation were monitored. Reaction kinetic of these processes was also assessed. A rapid reaction took place for Fenton process at higher initial concentration of H2O2, higher temperatures, and more acidic conditions (pH 3). Similarly, ozonation reaction exhibited rapid rates for higher ozone dose, higher temperatures, and more basic conditions (pH 11). Complete NB degradation in 65 min was achieved using Fenton process. The conditions of complete elimination of 100 mg/L of initial NB concentration, were 250 mg/L of H202 concentration, pH 3, and 10 mg/L of Fe(Ⅱ) concentration. Under these conditions, 55% organic carbon elimination was achieved. Total organic carbon mineralization was attained in 240 rain reaction time by Fenton process with 900 mg/L of H202 concentration, and 30 mg/L of Fe(Ⅱ) concentration. Fenton reaction showed a pseudo-first order kinetic; the reaction rate constant was ranged from 0.0226 to 0.0658 min^-1. Complete NB degradation was also achieved for an ozone dose of the order of 2.5 g/L. The ozonation was studied at different ozone doses, different initial pH (7-11) and at different temperatures (15-35℃). NB ozonation kinetic was represented by a bi-molecular kinetic model which was reduced to pseudo-first order kinetic. The pseudo-first order reaction rate constant was determined to increase at 20℃ from 0.004 to 0.020 min^-1 as the used ozone increased from 0.4 to 1.9 g/L. 展开更多
关键词 nitro-aromatics chemical oxidation organic matter content
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Treatment of O-nitro-phenol Wastewater with Magnetization-Enhanced Oxidation by NaCIO Solution
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作者 P. Zhang X.G. Liu L. Zhong 《Journal of Environmental Science and Engineering》 2010年第10期31-34,共4页
关键词 硝基苯酚废水 磁化处理 氧化剂 增强型 邻硝基酚 反应时间 污染物浓度 CODCR
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Quantitative Assessment of the Effect of Nitric Oxide Synthase Inhibition on Tumor Vascular Activity Using Dynamic Contrast-Enhanced Computed Tomography 被引量:1
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作者 Kenya Murase Yoshinori Kusakabe Shohei Miyazaki 《Open Journal of Medical Imaging》 2016年第2期42-52,共12页
Purpose: The purpose of this study was to develop a method to quantitatively assess the effect of nitric oxide synthase (NOS) inhibition on tumor vascular activity using dynamic contrast-enhanced computed tomography (... Purpose: The purpose of this study was to develop a method to quantitatively assess the effect of nitric oxide synthase (NOS) inhibition on tumor vascular activity using dynamic contrast-enhanced computed tomography (DCE-CT) and to investigate its usefulness using animal experiments. Mate-rials and Methods: The DCE-CT studies were performed in anesthetized Fisher rats bearing tumors using a 4-row multi-slice CT. The scanning started 4 s before a bolus injection of iodinated contrast agent (CA) (150 mgI/kg) from the tail vein using an automatic injector and lasted 60 s at 1-s in-tervals. The contrast enhancement (CE) images were generated by subtracting the CT images before and after the administration of CA. First, the DCE-CT studies were performed before and 15, 30, and 45 min after administration of N-nitro-L-arginine (L-NNA) (1, 3, and 10 mg/kg) or vehicle, and the relative CE values were calculated by normalizing the CE image at each time point by that obtained from the first DCE-CT study. Second, we investigated the case when L-arginine (L-ARG) (200 mg/kg) and L-NNA (1, 3, and 10 mg/kg) were administered after the first and second DCE-CT studies, respectively. Third, we investigated the case when L-NNA (1, 3, and 10 mg/kg) and L-ARG (200 mg/kg) were administered after the first and second DCE-CT studies, respectively. Finally, we investigated the case when L-NNA (1, 3, and 10 mg/kg) and L-ARG (200 mg/kg) were administered simultaneously after the first DCE-CT study. Results: The relative CE value significantly decreased after L-NNA administration in a dose-dependent manner (p-values = 0.0074 and <0.0001 for 0 vs. 3 mg/kg and 0 vs. 10 mg/kg, respectively, at 15 min, 0.0003 and <0.0001 for 0 vs. 3 mg/kg and 0 vs. 10 mg/kg, respectively, at 30 min, and 0.0367 and 0.0004 for 0 vs. 3 mg/kg and 0 vs. 10 mg/kg, respectively, at 45 min). When L-ARG was administered prior to the administration of 1 mg/kg L-NNA, the relative CE value at 45 min was significantly higher than that at 15 min. When L-ARG was administered after L-NNA administration, there was no significant difference between the relative CE values at 15 min and 45 min. These results suggest that when using L-NNA in combination with L-ARG, their effect on tumor vascular activity differs depending on the order of their administration. When L-NNA and L-ARG were administered simultaneously, there was a tendency for the relative CE value to be higher than that when only L-NNA was administered, at all injected doses of L-NNA. Conclusion: Our method using DCE-CT is useful for monitoring the effect of NOS inhibition on tumor vascular activity and for determining the optimal injected dose and timing of NOS inhibitors for anticancer therapy. 展开更多
关键词 Nitric oxide Synthase N-nitro-L-Arginine L-ARGININE Tumor Vascular Activity Dynamic Contrast-Enhanced Computed Tomography Contrast Enhancement
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内皮型一氧化氮合酶在运动预适应改善心肌缺血-再灌注损伤中的作用 被引量:1
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作者 娄国 张艳 付常喜 《中国组织工程研究》 CAS 北大核心 2024年第8期1283-1288,共6页
背景:运动是防治各种心血管疾病并保护心脏免受缺血-再灌注损伤的有效策略,其作用机制有待深入研究。目的:观察有氧运动预适应对心肌缺血-再灌注损伤的影响,并探讨内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)激活(包... 背景:运动是防治各种心血管疾病并保护心脏免受缺血-再灌注损伤的有效策略,其作用机制有待深入研究。目的:观察有氧运动预适应对心肌缺血-再灌注损伤的影响,并探讨内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)激活(包括偶联和磷酸化)在其间的作用。方法:取80只成年Wistar大鼠,采用随机数字表法分为安静组(n=40)和运动组(n=40),运动组进行8周有氧运动,安静组在鼠笼内安静饲养。8周后进行3项实验:①实验1:末次训练后,检测大鼠心功能、心脏NO代谢物含量及心脏eNOS、磷酸化eNOS-S1177、eNOS二聚体、eNOS单体的蛋白表达量;②实验2:将大鼠分为安静对照组、运动对照组、安静+eNOS抑制剂组、运动+eNOS抑制剂组,均进行体外心肌缺血-再灌注损伤实验,安静+eNOS抑制剂组、运动+eNOS抑制剂组再灌注前10 min持续灌注eNOS抑制剂,再灌注3 h后检测心功能与心肌梗死面积;③实验3:将大鼠分为安静对照组、运动对照组、安静+eNOS偶联剂组和运动+eNOS偶联剂组,均进行体外心肌缺血-再灌注损伤实验,安静+eNOS偶联剂组和运动+eNOS偶联剂组再灌注前10 min持续灌注eNOS偶联剂,再灌注3 h后检测心肌梗死面积、心脏NO代谢物含量及心脏eNOS、磷酸化eNOS-S1177、eNOS二聚体、eNOS单体和3-硝基酪氨酸的蛋白表达量(其中,磷酸化eNOS-S1177/eNOS比值反映eNOS磷酸化/去磷酸化水平,eNOS二聚体/单体比值反映eNOS偶联/解偶联水平)。结果与结论:①实验1:与安静组比较,运动组大鼠心输出量、左心室射血分数升高(P<0.05),亚硝酸盐和S-亚硝基硫醇含量升高(P<0.05),磷酸化eNOS-S1177、eNOS蛋白表达和磷酸化eNOS-S1177/eNOS比值上调(P<0.05),eNOS二聚体蛋白表达和eNOS二聚体/单体比值升高(P<0.05);②实验2:与安静对照组比较,运动对照组左心室发展压升高(P<0.05),心肌梗死面积下降(P<0.05);与运动对照组比较,运动+eNOS抑制剂组左心室发展压降低(P<0.05),心肌梗死面积增加(P<0.05);③实验3:与安静对照组比较,运动对照组左心室发展压升高(P<0.05),心肌梗死面积下降(P<0.05),磷酸化eNOS-S1177/eNOS比值下降(P<0.05),eNOS二聚体/单体比值下降(P<0.05),S-亚硝基硫醇含量增加(P<0.05),3-硝基酪氨酸蛋白表达量下调(P<0.05);与运动对照组比较,运动+eNOS偶联剂组左心室发展压降低(P<0.05),心肌梗死面积增加(P<0.05),磷酸化eNOS-S1177/eNOS比值升高(P<0.05),eNOS二聚体/单体比值升高(P<0.05),3-硝基酪氨酸蛋白表达升高(P<0.05);④结果表明:有氧运动预适应可诱导心脏保护效应,其机制与心脏缺血-再灌注期间eNOS解偶联以及去磷酸化进而抑制NO过度产生并降低硝基-氧化应激有关。 展开更多
关键词 运动预适应 内皮型一氧化氮合酶 磷酸化/去磷酸化 偶联/解偶联 缺血-再灌注损伤 硝基-氧化应激
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THE ROLE OF NITRIC OXIDE IN SMALL INTESTINAL MIGRATING MOTOR COMPLEX
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作者 吴建维 罗金燕 +3 位作者 蒋予 龚均 张宽学 董蕾 《Journal of Pharmaceutical Analysis》 CAS 1998年第2期163-169,共7页
The main objective is to study the role or nitric oxide (NO) in small Intestinal migratingmotor complex (MMC). Rats were implanted with strain gauges in the duobenum and jejunum forrecording the motor action of the sm... The main objective is to study the role or nitric oxide (NO) in small Intestinal migratingmotor complex (MMC). Rats were implanted with strain gauges in the duobenum and jejunum forrecording the motor action of the small intestine in fasting and red states arter intravenous infusionof N'-nitro-L-arginine methyl ester (L-NAME ), L-arginin., D-arglnine, sodium nitropusside(NaNP) and angiotensin 1 respectively. The results showed that intravenous inrusion or L-NAME,a NO synthase inhibitor, induced a fasting-like MMC motor pattern in fed rats. Infusion of NaNP, aNO donor, disrupted small intestinal MMC in fasting rats, inducing a postprandial-like motor pattern. Both fasting and postprandial, infusion of L-NAME shortened the duration or Phase I andphase Ⅱ,but didn't chang. the duration, frequency, amplitude and s,eed or Propogatiou of thephaSe, Ⅲ-argining, not D-arginine infused together with L-NAME, prevented the effect of LNAME infusion. Infusion of L-arginine, D-arginine or angioteusin Ⅰ alone didn't modify the smallintestinal motor pattern. It suggests that an inhibition of NO synthesis may be involved in the initiation of the MMC motor pattern during fasting, whereas an increase of NO output relates to the occurrence of the fed motor pattern 展开更多
关键词 nitric oxide (NO) migrating motor complex (MMC) small intestine N^G-nitro-Larginine methyl ester (L-NAME)
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7-nitro-indazole 减小大鼠暂时性局灶性脑梗塞灶范围 被引量:6
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作者 姜德华 金南革 +1 位作者 玄汉石 李在琉 《中风与神经疾病杂志》 CAS CSCD 北大核心 1998年第6期342-344,共3页
目的探讨神经元型一氧化氮合酶(nNOS)在暂时性局灶性脑缺血中的作用。方法用栓线法建立了大脑中动脉阻塞(MCAO)模型的大鼠上,观察特异性nNOS抑制剂7-nitro-indazole(7-NI)对大鼠缺血3h、再灌... 目的探讨神经元型一氧化氮合酶(nNOS)在暂时性局灶性脑缺血中的作用。方法用栓线法建立了大脑中动脉阻塞(MCAO)模型的大鼠上,观察特异性nNOS抑制剂7-nitro-indazole(7-NI)对大鼠缺血3h、再灌注3h脑梗塞灶范围的影响。结果7-NI(25mg/kg)可减小大鼠脑梗塞灶范围,且主要减小大脑皮质梗塞灶,其作用可被L-精氨酸(300mg/kg)逆转,D-精氨酸(300mg/kg)则否。 展开更多
关键词 脑缺血 一氧化氮 一氧化氮合酶 脑梗塞 抑制剂
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Genistein影响AGE-BSA诱导牛视网膜微血管内皮细胞内吞的实验研究 被引量:3
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作者 刘学政 伍刚 +1 位作者 王大江 范铁艳 《锦州医学院学报》 2003年第6期4-11,共8页
目的 视网膜内皮细胞内吞加强和视网膜微血管渗漏密切相关。近年的研究表明晚期糖基化终末产物(AGEs)可造成实验动物视网膜微血管的渗漏 ,但是其确切机制尚不明确。本实验研究金雀异黄素 (genisteinGen)对糖基化修饰的牛血清白蛋白 (AG... 目的 视网膜内皮细胞内吞加强和视网膜微血管渗漏密切相关。近年的研究表明晚期糖基化终末产物(AGEs)可造成实验动物视网膜微血管的渗漏 ,但是其确切机制尚不明确。本实验研究金雀异黄素 (genisteinGen)对糖基化修饰的牛血清白蛋白 (AGE -BSA)诱导视网膜微血管内吞、eNOS和NO变化的影响 ,以探讨糖基化终末产物造成视网膜微血管渗漏的机制。方法 体外培养并纯化牛视网膜微血管内皮细胞 (BREC)近融合后进行实验。检测不同浓度AGE -BSA在不同时间对BREC内吞辣根过氧化物酶 (HRP)情况。在此基础上研究Genistein对AGE -BSA诱导BREC内吞、eNOS活性和NO浓度的影响。结果 Gen抑制AGE -BSA诱导体外培养的BREC内吞 ,并对由AGE -BSA诱导的eNOS -NO系统活化也有抑制作用。结论 DR早期微血管渗漏发生机制较为复杂 ,AGE -BSA诱导内皮细胞内吞活跃和渗漏发生有关。Gen作为大豆提取物可以抑制实验性BREC内吞 。 展开更多
关键词 糖网病 金雀异黄素 内吞 一氧化氮 一氧化氮合酶
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急性冠脉综合征患者血清ACE2、suPAR水平与氧化应激损伤及不良预后的关系
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作者 李攀 程国杰 +2 位作者 田苗苗 孙越红 李彦卓 《新疆医科大学学报》 CAS 2024年第3期365-371,共7页
目的 探讨急性冠脉综合征(Acute coronary syndrome, ACS)患者血清血管紧张素转化酶2(Angiotensin converting enzyme 2,ACE2)、可溶性尿激酶型纤溶酶原激活物受体(Soluble urokinase type plasminogen activator receptor, suPAR)与氧... 目的 探讨急性冠脉综合征(Acute coronary syndrome, ACS)患者血清血管紧张素转化酶2(Angiotensin converting enzyme 2,ACE2)、可溶性尿激酶型纤溶酶原激活物受体(Soluble urokinase type plasminogen activator receptor, suPAR)与氧化应激损伤及不良预后的关系。方法 选择2019年9月-2022年9月大兴区人民医院收治的125例ACS患者作为ACS组,并选取与之性别、年龄相匹配的50例冠脉造影结果完全正常者作为对照组,比较两组血清ACE2、suPAR及氧化应激指标[丙二醛(Malondialdehyde, MDA)、过氧化脂质(Lipid peroxide, LPO)、超氧化物歧化酶(Superoxide dismutase, SOD)]水平,并分析血清ACE2、suPAR与氧化应激、不良预后的关系。结果 与对照组比较,ACS组ACE2、suPAR、MDA、LPO升高(P<0.05),SOD下降(P<0.05)。轻度病变、中度病变、重度病变患者ACE2、suPAR及冠脉狭窄Gensini评分显著上升(P<0.05)。ACS患者ACE2、suPAR与MDA、LPO、Gensini评分呈正相关(P<0.05),与SOD呈负相关(P<0.05)。与预后良好患者比较,预后不良患者年龄、发病至就诊时间、Gensini评分、ACE2、suPAR、MDA、LPO升高(P<0.05),LVEF、SOD降低(P<0.05)。年龄、发病至就诊时间、Gensini评分、ACE2、suPAR、MDA、LPO是ACS预后不良的危险因素(P<0.05),LVEF、SOD为其保护因素(P<0.05)。血清ACE2联合suPAR预测ACS预后不良的效能较高,其曲线下面积(Area under curve,AUC)为0.894。结论 ACS患者血清ACE2、suPAR高表达与氧化应激损伤、不良预后显著相关。 展开更多
关键词 急性冠脉综合征 血管紧张素转化酶2 可溶性尿激酶型纤溶酶原激活物受体 氧化应激损伤 不良预后
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某燃气轮机电厂启动全过程无硝黄烟排放操作方法
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作者 张石凯 程硕 +3 位作者 黄庆 周建 朱为东 唐寅 《南方能源建设》 2024年第4期144-155,共12页
[目的]某燃气轮机电厂的GE-PG9351FA型燃气轮机发电机组,目前采用DLN2.0+燃烧器,设计NO_(x)(氮氧化物)排放浓度为50 mg/m^(3),启动过程中大量排放黄色烟雾,已无法满足《火电厂大气污染物排放标准》(GB 13223—2011)要求,频繁遭到周围居... [目的]某燃气轮机电厂的GE-PG9351FA型燃气轮机发电机组,目前采用DLN2.0+燃烧器,设计NO_(x)(氮氧化物)排放浓度为50 mg/m^(3),启动过程中大量排放黄色烟雾,已无法满足《火电厂大气污染物排放标准》(GB 13223—2011)要求,频繁遭到周围居民举报。根据江苏环保排放新规,自2023年1月1日起,NO_(x)折算排放全程小时均值均小于30 mg/m^(3)。针对该种型号燃烧器进一步降低NO_(x)且解决启动过程中硝黄烟排放的需求,电厂采用余热锅炉烟道SCR脱硝改造技术,且对启动过程各指标控制进行数据模拟推演、分析总结,提炼出合理的启动操作方法。[方法]为验证该操作方法的可行性,电厂进行了多次调峰启动过程操作试验,并根据实际NO_(x)排放特性修正操作方法中的启动时刻、燃气轮机负荷控制、SCR脱硝系统投入节点,形成最优化操作法。[结果]试验结果表明:在优化电厂SCR脱硝系统投入时刻、燃气轮机启动时刻、并网后暖机负荷后,NO_(x)折算排放全程小时均值均小于30 mg/m^(3),且硝黄烟排放现象消失。[结论]该操作策略是基于燃气轮机启动过程NO_(x)与硝黄烟排放特性而得出,后期通过数据推演和大量试验验证,可为同类型燃气轮机启动过程降低氮氧化物与硝黄烟现象提供直接指导,并为燃气轮机电厂调峰运行的NO_(x)排放控制提供分析借鉴思路。 展开更多
关键词 燃气轮机电厂 氮氧化物 硝黄烟 模拟推演 启动时刻 暖机负荷 排放控制
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Hydrogen sulfide defends against the cardiovascular risk of Nw-nitro-L-argininemethyl ester-induced hypertension in rats via the nitric oxide/endothelial nitric oxide synthase pathway 被引量:3
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作者 Ji Wenqiang Liu Shangyu +4 位作者 Dai Jing Yang Tao Jiang Xiangming Duan Xiaocui Wu Yuming 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第21期3751-3757,共7页
Background Dyslipidemia caused by liver injury is a significant risk factor for cardiovascular complications.Previous studies have shown that hydrogen sulfide (H2S) protects against multiple cardiovascular disease s... Background Dyslipidemia caused by liver injury is a significant risk factor for cardiovascular complications.Previous studies have shown that hydrogen sulfide (H2S) protects against multiple cardiovascular disease states in a similar manner as nitric oxide (NO),and NO/endothelial nitric oxide synthase (eNOS) pathway is the key route of NO production.The purpose of this study was to investigate whether H2S can ameliorate the high blood pressure and plasma lipid profile in Nw-nitro-L-argininemethyl ester (L-NAME)-induced hypertensive rats by NO/eNOS pathway.Methods Thirty-six 4-week old Sprague-Dawley (SD) male rats were randomly assigned to 6 groups (n=6):control group,L-NAME group,control + glibenclamide group,control + NaHS group,L-NAME + NaHS group,and L-NAME + NaHS + glibenclamide group.Measurements were made of plasma triglycerides (TG),low-density lipoprotein (LDL),high-density lipoprotein (HDL),total cholesterol (CHO),glutamic-pyruvic transaminase (ALT) levels after 5 weeks.Then measurements of NO level and proteins expression of eNOS,P-eNOS,AKT,P-AKT were made in liver tissue.Results After 5 weeks of L-NAME treatment,the blood pressure,plasma TG ((1.22±0.12) mmol/L in L-NAME group vs.(0.68±0.09) mmol/L in control group; P <0.05) and LDL ((0.54±0.04) mmol/L in L-NAME group vs.(0.28±0.02) mmol/L in control group; P <0.05) concentration were significantly increased,and the plasma HDL ((0.26±0.02) mmol/L in L-NAME group vs.(0.69±0.07) mmol/L in control group; P <0.05) concentration significantly decreased.Meanwhile the rats treated with L-NAME exhibit dysfunctional eNOS,diminished NO levels ((1.36±0.09) mmol/g protein in L-NAME group vs.(2.34±0.06) mmol/g protein in control group; P <0.05) and pathological changes of the liver.H2S therapy can markedly decrease the blood pressure ((37.25±4.46) mmHg at the fifth week; P <0.05),and ameliorate the plasma TG ((0.59±0.06) mmHg),LDL ((0.32±0.04) mmHg),and HDL ((0.46±0.03) mmHg) concentration in L-NAME + NaHS group (all P <0.05).H2S therapy can also restore eNOS function and NO bioavailability and attenuate the pathological changes in the liver in L-NAME-induced hypertensive rats.Conclusion H2S protects the L-NAME-induced hypertensive rats against liver injury via NO/eNOS pathway,therefore de.creases the cardiovascular risk. 展开更多
关键词 hydrogen sulfide Nw-nitro-L-argininemethyl ester nitric oxide KATP channel
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Potentielle Rolle der humanen DNA-Reparaturenzyme hMTH_1, hOGG_1 und hMYHα i n der Hepatokarzinogenese
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作者 程斌 林菊生 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第3期206-211,215,共7页
Zur Aufklarung der Rolle dreier DNA Reparaturenzyme in der Hepatokarzino genese haben wir die hMTH 1,hOGG 1 und hMYHα mRNA Expression mittels RT/semi quantitativer Echtzeit PCR und der 8 OHdG Gehalt mittels H... Zur Aufklarung der Rolle dreier DNA Reparaturenzyme in der Hepatokarzino genese haben wir die hMTH 1,hOGG 1 und hMYHα mRNA Expression mittels RT/semi quantitativer Echtzeit PCR und der 8 OHdG Gehalt mittels HPLC/ECD in Tumor und Peritumorgewebe von 21 Patienten mit hepatozellularem Karzinom (HCC ) bestimmt. Es wurde gezeigt, da der 8 OHdG Gehalt im Peritumorgewebe signif ikant hoher als im Tumorgeweb e war ( P =0.006) und mit dem Entzundungsgrad korrelierte. Die hMTH 1 E xpression war im Tumorgewebe gegenuber dem Peritumorgewebe erhoht ( P =0.014). Umgekehrt war die hMYHα Expression im Peritumorgewebe signifikant hoher als im Tumorgewebe ( P =0.039). Fur die hOGG 1 Expression wurde kein deutlicher Unterschied zwischen Tumor und Peritumorgewebe beobachte t. Eine deutliche lineare Korrelation zwischen der hMTH 1 und der hOGG 1 Exp ression wurde sowohl in Tumor ( r =0.809, P < 0.001) als auch in Peritum orgewebe ( r =0.883, P <0.001) gefunden. Diese Daten sprechen fur ein e reaktive und gegen eine pathogenetische Rolle der untersuchten DNA Reparature nzyme in der Hepatokarzinogenese. 展开更多
关键词 oxidative Stress DNA Repara tur hMTH 1 gen hOGG 1 gen hMYHα gen Hepatokarzinogenese
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Effect of alpha-lipoic acid supplementation on blood pressure, renal oxidant-antioxidant status and renal damage in spontaneously hypertensive rats
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作者 Chandran Govindasamy Sirajudeen KNS 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2019年第10期415-423,共9页
Objective:To investigate the effect of alpha-lipoic acid(ALA)supplementation on systolic blood pressure(SBP),renal oxidant-antioxidant status and renal damage in spontaneously hypertensive rats(SHR)and SHR administere... Objective:To investigate the effect of alpha-lipoic acid(ALA)supplementation on systolic blood pressure(SBP),renal oxidant-antioxidant status and renal damage in spontaneously hypertensive rats(SHR)and SHR administered with Nω-nitro-L-arginine methyl ester(L-NAME).Methods:Male rats were divided into four groups(SHR,SHR+ALA,SHR+L-NAME,SHR+ALA+L-NAME).The respective group of rats was administered with ALA(100 mg/kg/day)from age 4 weeks to 28 weeks and L-NAME(25 mg/kg/day)from age 16 weeks to 28 weeks.SBP was measured every two weeks and twenty four hour urine was collected at 4 weeks,16 weeks and 28 weeks for estimation of protein,creatinine and N-acetyl-e end of 28 weeks,rats were sacrificed and blood and kidneys colα-Dglucosaminidase.At thlected for assessment of blood creatinine,kidney thiobarbituric acid reactive substances,protein carbonyls,superoxide dismutase,catalase,glutathione peroxidase,glutathione reductase,glutathione S-transferase,glutathione disulfide,glutathione,total antioxidant status and nitric oxide as well as histopathological examination.Results:ALA supplementation significantly reduced SBP of SHR and SHR+L-NAME rats when compared to their respective non-supplemented groups.Renal oxidant status markers including thiobarbituric acid reactive substances and protein carbonyls were significantly reduced on SHR and SHR+L-NAME rats supplemented with ALA at 28 weeks as well as ALA supplementation significantly increased renal antioxidants including superoxide dismutase,catalase,glutathione peroxidase,glutathione S-transferase,glutathione and glutathione/glutathione disulfide ratio at 28 weeks.No significant change in nitric oxide levels was observed between the ALA supplemented and non-supplemented groups.Renal dysfunction was ameliorated on ALA supplementation as evidenced by significant reduction in urine protein levels,N-acetyl-α-D-glucosaminidase activity and significant increase of creatinine clearance in SHR and SHR+L-NAME at 28 weeks.Renal histopathological examination showed that ALA supplementation prevented vascular damage in SHR and ameliorated glomerular damage in SHR+L-NAME at 28 weeks.Conclusions:ALA has hypotensive and renoprotective effects on both SHR and SHR+LNAME,which could be due to its ability to ameliorate oxidative stress in the kidneys. 展开更多
关键词 Alpha-lipoic acid Supplementation oxidative stress markers Spontaneously HYPERTENSIVE rat Nω-nitro-L-arginine methyl ester
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控释肥一次性侧深施对水稻生长、氮素利用和产量的影响 被引量:3
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作者 宋文杰 罗嘉润 +3 位作者 刘伟 张大弘 李燕丽 卢碧林 《华中农业大学学报》 CAS CSCD 北大核心 2023年第2期99-107,共9页
为探索机插水稻一次性侧深基施的轻简高效栽培技术,以水稻品种“全两优鄂丰丝苗”为材料,设置不施肥(N0)、控释肥一次性侧深基施(N1)、控释肥减氮10%一次性侧深基施(N2)、控释肥减氮20%一次性侧深基施(N3)和传统施肥(CK)处理,测定水稻... 为探索机插水稻一次性侧深基施的轻简高效栽培技术,以水稻品种“全两优鄂丰丝苗”为材料,设置不施肥(N0)、控释肥一次性侧深基施(N1)、控释肥减氮10%一次性侧深基施(N2)、控释肥减氮20%一次性侧深基施(N3)和传统施肥(CK)处理,测定水稻分蘖动态、主要生育期的叶面积指数与干物质积累量、齐穗期根系指标、氮素利用效率与产量,研究控释肥一次性侧深施对水稻生长、氮素吸收利用和产量的影响。结果显示:与CK相比,处理N1、N2显著增产12.99%~14.85%和5.47%~6.09%,处理N3产量与CK差异不显著,对施肥量和产量拟合后分析,在减氮18.72%时与CK产量持平。与CK相比,控释肥一次性侧深施处理显著提高了水稻的成穗率、提高了生育中后期的叶面积指数和干物质积累量、促进了根系的生长并扩大了根系的分布范围,处理N1、N2和N3与处理CK相比,分别提高氮素表观利用率1.21%~46.57%、氮素农学利用率18.85%~61.73%、氮素生理利用率8.90%~17.71%和偏生产力12.99%~23.61%。研究结果表明,控释肥一次性侧深施促进了根系生长,增加水稻有效穗数,提高了氮素利用效率且大幅较少施肥次数,在减氮18.72%的范围内,可实现水稻的高产、稳产。 展开更多
关键词 轻简高效栽培 控释肥 侧深施肥 氮肥运筹 减氮施肥 水稻生长 产量 氮素利用率
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黑龙江省西部主要草地类型土壤和植被特征
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作者 方玉凤 曹志伟 +6 位作者 韩勤 闫敦梁 任秀彬 温宝阳 高野 汤羽佳 邹春明 《草原与草坪》 CAS CSCD 2023年第5期129-136,共8页
【目的】明确松嫩平原未退化草地土壤与植被现状,为松嫩平原天然草原生态系统保护及草原可持续利用提供科学依据。【方法】在黑龙江省西部选取松嫩平原草原区域内的杜蒙、林甸和肇东等县市典型未退化围栏封育天然草原进行样地调查分析,... 【目的】明确松嫩平原未退化草地土壤与植被现状,为松嫩平原天然草原生态系统保护及草原可持续利用提供科学依据。【方法】在黑龙江省西部选取松嫩平原草原区域内的杜蒙、林甸和肇东等县市典型未退化围栏封育天然草原进行样地调查分析,研究草原群落组成、土壤特征变化情况,分析二者之间的关系。【结果】根据立地类型和植被特征,将未退化天然草原划分为温性草甸草原和低地草甸;温性草甸草原的群落物种数、丰富度指数、香农威纳指数均高于低地草甸,上、中、下层群落分布较均匀;低地草甸土壤pH值和电导率普遍高于温性草甸草原,土壤容重低于温性草甸草原。温性草甸草原的地上生物量、土壤全氮和有机质含量普遍低于低地草甸。土壤含水率与物种数、丰富度指数显著负相关性(P<0.05)。【结论】松嫩平原天然未退化典型草原的群落盖度仍保持较高水平,群落密度受表层土壤养分的影响较大;地带性温性草甸草原的物种多样性要优于非地带性的低地草甸,但土壤养分状况不及低地草甸。 展开更多
关键词 松嫩平原 温性草甸草原 低地草甸 群落构成 土壤全氮 有机质含量
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冀北退化草原生态修复研究
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作者 宋海燕 耿金川 +1 位作者 刘丹 李晓飞 《河北林业科技》 2023年第4期5-12,共8页
为修复冀北退化草原生态,该试验在丰宁县外沟门草原设置了5个施氮水平(0、60、120、180、240kg/hm^(2)),以紫花苜蓿、苇状羊茅单播和混播(1:2、1:1、2:1)改良草地。研究了在不同施氮水平下,单播和混播对牧草产量的影响及混播物种的竞争... 为修复冀北退化草原生态,该试验在丰宁县外沟门草原设置了5个施氮水平(0、60、120、180、240kg/hm^(2)),以紫花苜蓿、苇状羊茅单播和混播(1:2、1:1、2:1)改良草地。研究了在不同施氮水平下,单播和混播对牧草产量的影响及混播物种的竞争关系,为建植高产、稳定、可持续的混播草地提供理论基础。结果显示:施氮水平和混播方式显著影响牧草产量。混播相较于单播,具有较大产量优势。混播比例对种间竞争关系有直接影响。施氮量从60kg/hm^(2)增加到120kg/hm^(2)时,产量和增产率急剧增加,随着施氮量的进一步提高,产量和增产率增长变缓。施氮量为240kg/hm^(2)时,不同播种方式牧草产量均达到最大。紫花苜蓿对氮肥的响应弱于苇状羊茅,紫花苜蓿对于苇状羊茅具有更强的竞争优势。混播草地中苇状羊茅比例越低,种间竞争作用就越强烈,减少竞争力较强的紫花苜蓿比例,有助于种间关系共存稳定。因此,在丰宁半干旱草原地区,建植第1年施氮量为120kg/hm^(2),紫花苜蓿、苇状羊茅1:2混播时,可以实现最优产量。 展开更多
关键词 冀北 退化草原 紫花苜蓿 苇状羊茅 混播 施氮量
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Copper(Ⅱ)-catalyzed enantioselective conjugate addition of nitro esters to 2-enoyl-pyridine N-oxides
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作者 Jianan Sun Yanan Li +3 位作者 Yang Gui Youguo Xu Zhenggen Zha Zhiyong Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期569-572,共4页
A highly enantioselective Michael addition of nitro esters to 2-enoyl-pyridine N-oxides was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields and with up to 96% e... A highly enantioselective Michael addition of nitro esters to 2-enoyl-pyridine N-oxides was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields and with up to 96% ee. Moreover, asymmetric Michael addition product of nitromethane to 2-enoyl-pyridine N-oxides can be obtained in one step. An analogue of nicotine, dihydro-2H-pyrrol 4b was synthesized with this developed method. 展开更多
关键词 Michael reaction Asymmetric CATALYSIS COPPER CATALYSIS nitro ESTERS 2-Enoyl-pyridine N-oxideS
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种植密度对不同玉米品种叶片光合特性与碳、氮变化的影响 被引量:91
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作者 陈传永 侯海鹏 +4 位作者 李强 朱平 张振勇 董志强 赵明 《作物学报》 CAS CSCD 北大核心 2010年第5期871-878,共8页
选用玉米品种先玉335、郑单958和吉单209,设计了6.0、7.5、9.0和10.5万株hm-24个种植密度。测定了不同生育时期(吐丝期为重点)的叶片叶绿素含量、可溶性糖含量、全氮含量与碳氮比的动态变化。结果表明,3个品种的叶片叶绿素含量在灌浆期... 选用玉米品种先玉335、郑单958和吉单209,设计了6.0、7.5、9.0和10.5万株hm-24个种植密度。测定了不同生育时期(吐丝期为重点)的叶片叶绿素含量、可溶性糖含量、全氮含量与碳氮比的动态变化。结果表明,3个品种的叶片叶绿素含量在灌浆期最高,可溶性糖含量在吐丝期最高,碳氮比在吐丝期与成熟期出现2个高峰;叶绿素含量、灌浆期光合速率、叶片可溶性糖、全氮、碳氮比均随种植密度增加而降低;吐丝后光合速率呈下降趋势;吐丝后生育天数与叶绿素含量、光合速率、可溶性糖、C/N呈二次曲线关系,与全氮含量呈线性关系;高种植密度主要影响叶片碳代谢;叶绿素含量不是影响吐丝后光合速率的主要因素。不同基因型耐密性不同,先玉335最好,郑单958次之,吉单209最差。 展开更多
关键词 春玉米 密度 叶绿素 碳氮比 光合速率
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