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聚乙烯醇/维生素C复合保鲜膜制备及其对白玉菇品质的影响 被引量:2
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作者 黄若男 刘陈梦 +1 位作者 吕俊阁 谭之磊 《食品研究与开发》 CAS 2024年第3期99-106,共8页
为提高白玉菇贮存和运输质量,保证其营养价值以及销售过程的品质,该研究以聚乙烯醇为基材,以维生素C(vitamin C,V_(C))为抗氧化剂,制备出不同含量聚乙烯醇(polyvinyl alcohol,PVA)/V_(C)保鲜膜,探讨含抗氧化剂的PVA保鲜膜的理化性能及... 为提高白玉菇贮存和运输质量,保证其营养价值以及销售过程的品质,该研究以聚乙烯醇为基材,以维生素C(vitamin C,V_(C))为抗氧化剂,制备出不同含量聚乙烯醇(polyvinyl alcohol,PVA)/V_(C)保鲜膜,探讨含抗氧化剂的PVA保鲜膜的理化性能及其对白玉菇品质的影响。结果表明,含0.10%V_(C)的保鲜膜理化性能优异,满足包装材料的要求。采用PVA(0.10%V_(C))保鲜膜处理的白玉菇样品色泽和感官品质均较好,失重率仅为9.20%,样品中的总酚类物质以及蛋白质含量的保留率分别为54.00%和75.50%,与聚乙烯(polyethylene,PE)薄膜相比,其货架期延长4 d。 展开更多
关键词 白玉菇 聚乙烯醇和维生素c(PVA/V_(c))保鲜膜 采后保鲜 货架期 保鲜效果
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红细胞分布宽度-SD、尿酸、胱抑素C联合检测在急性缺血性脑卒中患者卒中后认知障碍中的诊断价值
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作者 张亚洁 赵培祥 +3 位作者 罗菊 孙慧芹 王允 田臻 《中国当代医药》 CAS 2024年第21期10-14,共5页
目的探讨红细胞分布宽度-SD、尿酸、胱抑素C在急性缺血性脑卒中患者发生卒中后认知障碍(PSCI)中的诊断价值。方法回顾性收集2022年3月至2023年3月于扬州大学附属淮安医院神经内科住院的161例急性缺血性脑卒中患者的临床资料。入院后次... 目的探讨红细胞分布宽度-SD、尿酸、胱抑素C在急性缺血性脑卒中患者发生卒中后认知障碍(PSCI)中的诊断价值。方法回顾性收集2022年3月至2023年3月于扬州大学附属淮安医院神经内科住院的161例急性缺血性脑卒中患者的临床资料。入院后次日检测患者外周血红细胞分布宽度-SD、白介素-6、超敏C反应蛋白、甘油三酯、胆固醇、胱抑素C、尿酸等水平。出院后3个月随访患者,根据蒙特利尔认知评估量表(Mo CA)分值将研究对象分为PSCI组和卒中后非认知障碍(NPSCI)组。比较两组患者的临床资料,采用logistic回归分析缺血性脑卒中后PSCI的危险因素。制作受试者操作特征(ROC)曲线,通过曲线下面积(AUC)分析红细胞分布宽度-SD、尿酸、胱抑素C及三者联合检测对PSCI的预测价值。结果PSCI组患者受教育年限低于NPSCI组,红细胞分布宽度-SD、胱抑素C、尿酸水平均高于NPSCI组,差异有统计学意义(P<0.05)。多因素logistic回归分析结果显示,红细胞分布宽度-SD(β=0.080,OR=1.084,95%CI:1.026~1.145)、胱抑素C(β=2.341,OR=10.387,95%CI:2.734~29.458)、尿酸(β=0.021,OR=1.021,95%CI:1.013~1.029)均是预测急性缺血性脑卒中患者发生PSCI的危险因素(P<0.05)。ROC曲线结果显示,红细胞分布宽度-SD、胱抑素C、尿酸水平预测急性缺血性脑卒中患者出现PSCI的AUC分别为0.745、0.773、0.863,三者联合检测的AUC为0.921,提示红细胞分布宽度-SD、尿酸、胱抑素C联合检测对急性缺血性脑卒中患者出现PSCI具有一定的预测价值。结论红细胞分布宽度-SD、尿酸、胱抑素C是急性缺血性脑卒中患者发生PSCI的危险因素,对缺血性脑卒中患者发生PSCI具有较好的预测价值。 展开更多
关键词 红细胞分布宽度 尿酸 胱抑素c 卒中后认知障碍
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磺胺甲恶唑对新型后置缺氧反硝化工艺处理低C/N废水的影响
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作者 张翼满 韩旭 王英刚 《水处理技术》 CAS CSCD 北大核心 2024年第5期119-123,共5页
磺胺甲恶唑(SMX)是废水内高频检出的新污染物,SMX的环境影响行为备受关注,然而SMX对新型后置反硝化工艺处理城镇低C/N废水的影响至今鲜有报道。本工作在中温条件下考察了SMX对新型后置缺氧反硝化工艺处理低C/N废水的影响,并通过分析SMX... 磺胺甲恶唑(SMX)是废水内高频检出的新污染物,SMX的环境影响行为备受关注,然而SMX对新型后置反硝化工艺处理城镇低C/N废水的影响至今鲜有报道。本工作在中温条件下考察了SMX对新型后置缺氧反硝化工艺处理低C/N废水的影响,并通过分析SMX暴露条件下新工艺胞内和胞外聚合物的变化规律揭示SMX对新工艺的影响机制。结果表明低于0.5 mg/L SMX对新工艺内污染物去除影响不明显,而超过1.0 mg/L降低了新工艺脱氮除磷效率,4.0 mg/L SMX组别内,COD、总氮(TN)和磷酸盐(SOP)去除效率分别下降至71.3%~75.5%、59.6%~63.4%和71.3%~73.6%。机制分析表明高浓度SMX降低了胞内聚合物PHA的生物合成而刺激了糖原质代谢。SMX暴露浓度越高,PHA生物合成下降越显著,而糖原质代谢越强烈。研究结果为新型后置缺氧工艺处理含SMX废水提供了一定的数据支撑。 展开更多
关键词 磺胺甲恶唑 后置缺氧反硝化 c/N废水 胞内聚合物 胞外聚合物
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人C/EBP β结构与功能的生物信息学分析及原核表达
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作者 陈利荣 刘玉玲 +2 位作者 贾艳梅 李佳佳 刘菲 《山西医科大学学报》 CAS 2024年第6期707-712,共6页
目的 研究人CCAAT/增强子结合蛋白β(CCAAT/enhancer binding proteins, C/EBP β)原核表达载体的构建和蛋白表达,并通过生物信息学分析其结构和生物学功能。方法 收集对数生长期的肝癌细胞SMMC-7721,通过TRIzol法提取SMMC-7721细胞内总... 目的 研究人CCAAT/增强子结合蛋白β(CCAAT/enhancer binding proteins, C/EBP β)原核表达载体的构建和蛋白表达,并通过生物信息学分析其结构和生物学功能。方法 收集对数生长期的肝癌细胞SMMC-7721,通过TRIzol法提取SMMC-7721细胞内总RNA,并以RNA为模板采用RT-PCR获得C/EBP β基因的编码序列,通过同源重组的方法将目的基因与原核表达质粒pET-28a(+)相连接,经过大肠杆菌转化、抗性筛选、质粒提取、酶切和DNA测序获得重组质粒pET-28a(+)-C/EBP β。将重组质粒导入大肠杆菌BL21中,通过异丙基-β-D-硫代半乳糖苷(isopropyl β-D-1-thiogal, IPTG)诱导C/EBP β重组蛋白表达,采用镍离子亲和层析法纯化C/EBP β融合蛋白,通过蛋白免疫印迹验证目的蛋白并分析C/EBP β的蛋白纯度。同时对人C/EBP β编码的蛋白质进行理化性质、亲水/疏水性、二级结构以及磷酸化位点等生物信息学分析。结果 通过RT-PCR成功获得人C/EBP β基因,构建的pET-28a(+)-C/EBP β重组质粒经测序鉴定C/EBP β DNA序列完全正确,表明重组pET-28a(+)-C/EBP β质粒构建成功。C/EBP β蛋白是一个性质不稳定的亲水蛋白质,由345个氨基酸组成,分子量为36.105 kD,等电点为8.55。其是一种胞内蛋白质,主要分布在细胞质和细胞核。对其结构分析发现:无规则卷曲是其主要的二级结构,为60.87%。蛋白免疫印迹结果显示通过亲和层析纯化后获得较高纯度的C/EBP β。结论 本实验成功克隆并构建人pET-28a(+)-C/EBP β重组质粒,获得较高纯度的C/EBP β,为进一步C/EBP β蛋白功能的研究和抗体的制备奠定了良好的基础。 展开更多
关键词 c/EBPΒ 重组质粒 原核表达 生物信息学 翻译后修饰
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Unraveling the Impact of Direct-Acting Antivirals on Hepatitis-Linked Cirrhosis: A Comprehensive Analysis of Fibrosis, Child Score, and Disease Progression
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作者 Hajar Cherkaoui Maryam Elkhayari +8 位作者 Maria Lahlali Asmae Lamine Nada Lahmidani Amine Mekkaoui Mounia Elyousfi Dafr Allah Benajah Mohammed El Abkari Adil Ibrahimi Hakima Abid 《Open Journal of Gastroenterology》 CAS 2024年第6期203-212,共10页
The treatment of hepatitis C has undergone a significant boom since the advent of direct acting antivirals (DAA). Indeed, the interferon-ribavirin combination that has been used to treat hepatitis C has a virological ... The treatment of hepatitis C has undergone a significant boom since the advent of direct acting antivirals (DAA). Indeed, the interferon-ribavirin combination that has been used to treat hepatitis C has a virological response in only 45% of cases with significant side effects. The advent of direct-acting antivirals has changed the prognosis of cirrhotic patients with hepatitis C. DAAs have ensured a sustained viral response in the majority of patients. Our work aims to see the evolution of hepatitis C patients at the cirrhosis stage under DAA. We conducted a retrospective study over 15 years (January 2009, January 2024) including all patients with post-viral cirrhosis C, whom we divided into two groups: group A, cirrhotic patients who received ribavirin and interferon, and group B, patients on DAA. From January 2009 to January 2024, we conducted a study of 182 patients with viral hepatitis C, including 102 cirrhotic patients. The mean age was 55 years. 66% of patients were initially treated with the ribavirin interferon combination, while 34% received direct-acting antivirals (DAAs). Since the introduction of DAAs, the most commonly used regimens have been sofosbuvir/daclatasvir with or without ribavirin and sofosbuvir/ledipasvir with or without ribavirin. Group A achieved sustained virological response (SVR) in 60% of cases, with notable side effects. In Group B, SVR was 98.18%, with improved tolerability and fewer side effects than previous treatments. Fifteen patients developed hepatocellular carcinoma (HCC), with a significantly lower mortality rate in those treated with DAAs compared with pegylated dual therapy (p: 0.001). 展开更多
关键词 post-Viral cirrhosis c Pegylated Interferon Direct Acting Antivirals Sustained Viral Response child Score FIBROSIS
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弯剪耦合作用下大尺寸碳纤维C型梁失效损伤模式分析
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作者 赵紫昱 杨曈 +1 位作者 张发 马丕波 《纺织学报》 EI CAS CSCD 北大核心 2024年第2期93-100,共8页
为进一步探究大尺寸碳纤维C型梁结构抗弯剪屈曲的承载性能,提出了一种可同时施加弯曲和剪切载荷并任意调节弯剪比的试验装置。通过设计3种不同弯剪耦合条件进行试验载荷的加载,使用应变片监测大尺寸碳纤维C型梁结构在屈曲以及后屈曲阶... 为进一步探究大尺寸碳纤维C型梁结构抗弯剪屈曲的承载性能,提出了一种可同时施加弯曲和剪切载荷并任意调节弯剪比的试验装置。通过设计3种不同弯剪耦合条件进行试验载荷的加载,使用应变片监测大尺寸碳纤维C型梁结构在屈曲以及后屈曲阶段应变分布状况。通过有限元模型对基于不同损伤准则的后屈曲行为进行预测。研究结果表明:大尺寸碳纤维C型梁在抗弯和抗弯剪耦合的载荷条件下,都具有优良的后屈曲承载能力;在2种弯剪耦合条件下,试验件分别在3.28倍和2.3倍设计载荷时发生梁腹板失稳现象,试验件进入后屈曲状态,继续进行弯剪耦合载荷的加载,达到4.6倍设计载荷后,样品出现局部损伤;采用Hashin和LaRC05准则对试验件损伤情况进行预测,破坏损伤形式分别为沿45°方向开始向外扩展和上部翼缘扭曲破坏。 展开更多
关键词 大尺寸c型梁 弯剪耦合 应变测量 后屈曲 损伤预测
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Effect of post treatment temperature and humidity conditions onfixation performance of CCA-C treated red pine and southern pine 被引量:1
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作者 郭爱龙 P.A.Cooper 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第3期141-146,共6页
Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m?3 are compared at temperature (T... Rates of fixation in chromated copper arsenate (CCA-C) treated red pine (Pinus resinosa Ait.) and southern pine (Pinus spp) sapwood specimens using retention of 1.5, 2.0, 6.4 kg·m?3 are compared at temperature (T) ranging from 70°C to 50°C and 5 different relative humidity (RH) conditions. The samples were investigated using the expressate method to follow chromium fixation. Red pine fixes faster than southern pine under all 11 post treatment schedules. The fixation rates for both species are not significantly different while the blocks were fixed under 6 fixation/drying schedules that differed only in the order of T/RH conditions applied. The rate of fixation of all samples in any fixation stage were reduced when the blocks were fixed under lower humidity conditions in spite of no change in chamber temperature. Some of this influence can be attributed to the effect of humidity on heat transfer into the wood and cooling of the wood surface. 展开更多
关键词 ccA-c FIXATION post treatment TEMPERATURE Relative humidity Red pine Southern pine
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Post-translational modifications of hepatitis C viral proteins and their biological significance 被引量:2
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作者 Jana Hundt Zhubing Li Qiang Liu 《World Journal of Gastroenterology》 SCIE CAS 2013年第47期8929-8939,共11页
Replication of hepatitis C virus(HCV)depends on the interaction of viral proteins with various host cellular proteins and signalling pathways.Similar to cellular proteins,post-translational modifications(PTMs)of HCV p... Replication of hepatitis C virus(HCV)depends on the interaction of viral proteins with various host cellular proteins and signalling pathways.Similar to cellular proteins,post-translational modifications(PTMs)of HCV proteins are essential for proper protein function and regulation,thus,directly affecting viral life cycle and the generation of infectious virus particles.Cleavage of the HCV polyprotein by cellular and viral proteases into more than 10 proteins represents an early protein modification step after translation of the HCV positivestranded RNA genome.The key modifications include the regulated intramembranous proteolytic cleavage of core protein,disulfide bond formation of core,glycosylation of HCV envelope proteins E1 and E2,methylation of nonstructural protein 3(NS3),biotinylation of NS4A,ubiquitination of NS5B and phosphorylation of core and NS5B.Other modifications like ubiquitination of core and palmitoylation of core and NS4B proteins have been reported as well.For some modifications such as phosphorylation of NS3 and NS5A and acetylation of NS3,we have limited understanding of their effects on HCV replication and pathogenesis while the impact of other modifications is far from clear.In this review,we summarize the available information on PTMs of HCV proteins and discuss their relevance to HCV replication and pathogenesis. 展开更多
关键词 HEPATITIS c VIRUS HEPATITIS c VIRUS PROTEINS post-TRANSLATIONAL modifications of PROTEINS HEPATITIS c VIRUS REPLIcATION HEPATITIS c VIRUS PATHOGENESIS
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Suppository naproxen reduces incidence and severity of post-endoscopic retrograde cholangiopancreatography pancreatitis: Randomized controlled trial 被引量:6
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作者 Fariborz Mansour-Ghanaei Farahnaz Joukar +2 位作者 Zahra Taherzadeh Homayoon Sokhanvar Tolou Hasandokht 《World Journal of Gastroenterology》 SCIE CAS 2016年第21期5114-5121,共8页
AIM: To determine the efficacy of rectally administered naproxen for the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).METHODS: This double-blind randomized control trial ... AIM: To determine the efficacy of rectally administered naproxen for the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).METHODS: This double-blind randomized control trial conducted from January 2013 to April 2014 at the Gastrointestinal and Liver Diseases Research Center in Rasht, Iran. A total of 324 patients were selected from candidates for diagnostic or therapeutic ERCP by using the simple sampling method. Patients received a single dose of Naproxen (500 mg; n = 162) or a placebo (n = 162) per rectum immediately before ERCP. The overall incidence of PEP, incidence of mild to severe PEP, serum amylase levels and adverse effects were measured. The primary outcome measure was the development of pancreatitis onset of pain in the upper abdomen and elevation of the serum amylase level to &#x0003e; 3 &#x000d7; the upper normal limit (60-100 IU/L) within 24 h after ERCP. The severity of PEP was classified according to the duration of therapeutic intervention for PEP: mild, 2-3 d; moderate 4-10 d; and severe, &#x0003e; 10 d and/or necessitated surgical or intensive treatment, or contributed to death.RESULTS: PEP occurred in 12% (40/324) of participants, and was significantly more frequent in the placebo group compared to the naproxen group (P &#x0003c; 0.01). Of the participants, 25.9% (84/324) developed hyperamylasemia within 2 h of procedure completion, among whom only 35 cases belonged to the naproxen group (P &#x0003c; 0.01). The incidence of PEP was significantly higher in female sex, in patients receiving pancreatic duct injection, more than 3 times pancreatic duct cannulations, and ERCP duration more than 40 min (Ps &#x0003c; 0.01). There were no statistically significant differences between the groups regarding the procedures or factors that might increase the risk of PEP, sphincterotomy, precut requirement, biliary duct injection and number of pancreatic duct cannulations. In the subgroup of patients with pancreatic duct injection, the rate of pancreatitis in the naproxen group was significantly lower than that in the placebo (6 patients vs 23 patients, P &#x0003c; 0.01, RRR = 12%, AR = 0.3, 95%CI: 0.2-0.6). Naproxen reduced the PEP in patients with &#x02265; 3 pancreatic cannulations (P &#x0003c; 0.01, RRR = 25%, AR = 0.1, 95%CI: 0.1-0.4) and an ERCP duration &#x0003e; 40 min (P &#x0003c; 0.01, RRR = 20%, AR = 0.9, 95%CI: 0.4-1.2).CONCLUSION: Single dose of suppository naproxen administered immediately before ERCP reduces the incidence of PEP. 展开更多
关键词 NAPROXEN Nonsteroidal anti-inflammatory drugs Pancreatic duct injection post-endoscopic retrograde cholangiopancreatography PANcREATITIS Serum amylase
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Plasma Post Oxidation of Plasma Nitrocarburized SKD 61 Steel 被引量:2
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作者 Insup Lee Kwang-Ho Jeong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第1期136-138,共3页
Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel.Plasma nitrocarburizing was conducted for 12 h at 540℃in the nitrogen, hydrogen and ... Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of SKD 61 steel.Plasma nitrocarburizing was conducted for 12 h at 540℃in the nitrogen, hydrogen and methane atmosphere to produce theε-Fe-(2-3)(N,C) phase.The compound layer produced by plasma nitrocarburising was predominantly composed ofε-phase,with a small proportion ofγ′-Fe-4 (N,C) phase. The thickness of the compound layer and the diffusion layer are about 10μm and about 200μm,respectively. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of 500℃for 1 h.The very thin magnetite (Fe-3O-4) layer of 1-2μm in thickness on top of the compound layer was obtained.Anodic polarization test revealed that plasma nitrocarburizing process contributed a significant improvement of corrosion resistance of SKD 61 steel.However,the corrosion characteristics of the nitrocarburized compound layer was deteriorated by oxidation treatment. 展开更多
关键词 Plasma nitrocarburizing post oxidation ε-Fe2-3(N c γ′-Fe4(N c Fe3O4
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Impact of Post Hepatitis C Chronic Liver Disease and Hepatocellular Carcinoma on Health Related Quality of Life
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作者 Somaia M. Ebeid Safaa H. Ali +2 位作者 Heba Y. Kamel Ahmed A. Elbaz Hazem M. El-Hariri 《Advances in Aging Research》 2015年第6期177-186,共10页
Background: Post hepatitis C virus chronic liver disease (CLD) is prevalent among the Egyptian population with a bad impact upon their quality of life (QOL). Hepatocellular carcinoma (HCC) is one of the long term and ... Background: Post hepatitis C virus chronic liver disease (CLD) is prevalent among the Egyptian population with a bad impact upon their quality of life (QOL). Hepatocellular carcinoma (HCC) is one of the long term and fatal complications of CLD and it also has its negative impact on patient’s quality of life. Aim: To assess impact of CLD and HCC on the quality of life of group of hospitalized elderly patients. Methodology: Ninety elderly patients were divided into three groups: 30 elderly with post hepatitis C virus CLD, 30 elderly with HCC and 30 others free of liver disease as control group (Cn), all were recruited from the in-patient ward and the outpatient clinic of the Geriatric Department, Ain-Shams University Hospital. After giving consent, comprehensive geriatric assessment was done with assessment of their quality of life by using the Short Form-36 health survey (SF-36). Investigations including liver enzymes, serum albumin, serum bilirubin and abdominal ultrasound were done. Results: All QOL domains were the highest among control group, followed by HCC group and the least among CLD group. The differences were statistically significant in most subscales and total score [Mean of Cn = 81.9 ± 12.4, Mean of CLD = 47.5 ± 21.9, Mean of HCC = 62.3 ± 16.1;P Cn/CLD ≤ 0.001, P Cn/HCC ≤ 0.001, P CLD/HCC = 0.004]. Albumin was the only biochemical marker correlated positively with total SF score and two subscales (PF and EF) [r = 0.408;P = 0.025]. Conclusion & Recommendation: Our study showed a decrease in the QOL of Egyptian post hepatitis C virus CLD and HCC patients compared with Egyptian population norms. The results showed that CLD were more affected than HCC patients. This had a particularly serious negative impact on their life. The findings indicate a need for updated counseling and educational materials designed to provide adequate information and consistent healthcare service to this patient setting. 展开更多
关键词 post HEPATITIS c VIRUS cHRONIc Liver DISEASES HEPATOcELLULAR carcinoma Quality of Life Short Form-36 Health Survey
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急性脑梗死患者早期血清中β2-微球蛋白和胱抑素-C水平与卒中后抑郁的关系 被引量:2
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作者 田雨晴 张嘉祯 +1 位作者 贾玉洁 闵连秋 《中风与神经疾病杂志》 CAS 2023年第3期257-260,共4页
目的探讨急性脑梗死患者早期血清β2-微球蛋白(β2-microglobulin,β2-MG)和胱抑素-C(Cystatin C,Cys-C)水平与卒中后抑郁(post-stroke depression,PSD)的相关性及其临床意义。方法连续收集首次发病72 h以内的急性脑梗死患者,诊断符合... 目的探讨急性脑梗死患者早期血清β2-微球蛋白(β2-microglobulin,β2-MG)和胱抑素-C(Cystatin C,Cys-C)水平与卒中后抑郁(post-stroke depression,PSD)的相关性及其临床意义。方法连续收集首次发病72 h以内的急性脑梗死患者,诊断符合《中国急性缺血性卒中诊治指南2018》的诊断标准,均经头部磁共振DWI证实,参照PSD的诊断标准和汉密尔顿抑郁评分量表24项版本(Hamilton Depression Scale-24,HAMD-24)评分纳入患者。评分≥8分纳入研究组(PSD组),PSD组再根据HAMD得分情况分为轻度和中-重度两个亚组。入院时收集血清β2-MG、Cys-C和生化等实验室指标及临床资料。结果174例急性脑梗死患者中诊断为PSD者64例、发生率为37%。与对照组相比,研究组患者在年龄、高血压、高密度脂蛋白胆固醇(high-density lipoprotein,HDL-C)、肌酐(serum creatinine,Scr)、β2-MG和Cys-C有统计学差异,经多因素Logistic回归分析结果显示年龄、β2-MG和Cys-C可能是PSD发生的独立危险因素;同时发现,β2-MG和Cys-C水平与PSD的严重程度成正相关(P<0.01)。应用ROC曲线对血清β2-MG和Cys-C在PSD诊断中的作用进行分析显示,β2-MG的AUC为0.781,敏感性为0.672、特异性为0.909;Cys-C的AUC为0.785,敏感性为0.828、特异性为0.736;联合诊断的AUC为0.815,敏感性为0.656、特异性为0.909。结论年龄、血清β2-MG和Cys-C可能是PSD发生的独立危险因素,且血清β2-MG和Cys-C与PSD的严重程度相关;β2-MG和Cys-C可能对PSD的发生有一定的诊断价值,二者联合诊断价值更高。 展开更多
关键词 脑梗死 卒中后抑郁 Β2-微球蛋白 胱抑素-c
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前置和后置反硝化处理低C/N印花废水对比研究 被引量:2
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作者 钱建英 《环境科技》 2023年第5期13-18,共6页
低C/N印花废水实际处理主要包括前置和后置反硝化工艺,处理过程中需要补充外加碳源作为反硝化碳源从而增加了运行成本。分别采用前置和后置反硝化工艺对低C/N印花废水进行脱氮研究,并对比2种工艺的脱氮效果及运行成本。结果表明,对于低... 低C/N印花废水实际处理主要包括前置和后置反硝化工艺,处理过程中需要补充外加碳源作为反硝化碳源从而增加了运行成本。分别采用前置和后置反硝化工艺对低C/N印花废水进行脱氮研究,并对比2种工艺的脱氮效果及运行成本。结果表明,对于低C/N的数码印花废水,当ρ(TN)低于300 mg/L时,采用前置反硝化工艺去除效果更好、更经济,NH_(3)-N和TN去除率分别为97.5%和96%,处理费用为5.368元/t,比后置反硝化工艺节约0.199元/t;当ρ(TN)高于300 mg/L时,采用后置反硝化工艺去除效果更好、更经济,NH_(3)-N和TN去除率分别大于97.5%和92%,处理费为5.871元/t,比前置反硝化工艺节约0.301元/t。 展开更多
关键词 c/N 印花废水 前置反硝化 后置反硝化 对比研究
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Plasma post oxidation of nitrocarburized AISI 4140 steel
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作者 LEE Insup 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期267-271,共5页
Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of AISI 4140 steel. Plasma nitrocarburizing was conducted for 3 h at 570 ℃ in the nitrogen, hydrogen... Plasma nitrocarburizing and plasma oxidizing treatments were performed to improve the wear and corrosion resistance of AISI 4140 steel. Plasma nitrocarburizing was conducted for 3 h at 570 ℃ in the nitrogen, hydrogen and methane atmosphere to produce the ε-Fe2-3(N,C) phase. It was found that the compound layer produced by plasma nitrocarburising was predominantly composed of ε-phase, with a small proportion of γ′-Fe4(N,C) phase. The thickness of the compound layer was about 10 μm and the diffusion layer was about 300 μm in thickness, respectively. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at a constant temperature of 500 ℃ for 1 h. The very thin magnetite (Fe3O4) layer 1-2 μm in thickness on top of the compound layer was obtained by plasma post oxidation. It was confirmed that the corrosion characteristics of the nitrocarburized compound layer can be further improved by the application of the superficial magnetite layer. 展开更多
关键词 plasma nitrocarburizing post oxidation ε-Fe2-3(N c) γ′-Fe4(N c) Fe3O4
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绝经后女性脑梗死后疲劳与性激素、Cys-C、CRP水平的相关性
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作者 杨朝霞 汤晶晶 姜文菊 《分子诊断与治疗杂志》 2023年第6期1086-1090,共5页
目的分析绝经后女性脑梗死后疲劳(PSF)与性激素、Cys-C、CRP水平的相关性。方法选取2020年5月至2022年9月期间北京世纪坛医院神经科收治的134例绝经后女性脑梗死患者的临床资料,将其中56例PSF患者作为PSF组,78例非PSF患者作为非PSF组,... 目的分析绝经后女性脑梗死后疲劳(PSF)与性激素、Cys-C、CRP水平的相关性。方法选取2020年5月至2022年9月期间北京世纪坛医院神经科收治的134例绝经后女性脑梗死患者的临床资料,将其中56例PSF患者作为PSF组,78例非PSF患者作为非PSF组,并同期选取134名行体检的健康绝经后女性为对照组,比较三组女性的血清性激素[E_(2)、FSH、LH、PRL、P、T]、Cys-C、CRP水平,并分析性激素、Cys-C、CRP水平与PSF严重程度[FSS评分]的相关性、对绝经后女性PSF的预测价值以及绝经后女性PSF发生的独立危险因素。结果PSF组、非PSF组女性的血清E_(2)、FSH、LH、PRL、P、T水平均低于对照组,而Cys-C、CRP水平均高于对照组,差异有统计学意义(P<0.05);PSF组血清E_(2)、T水平低于非PSF组,Cys-C、CRP水平高于非PSF组,差异有统计学意义(P<0.05);Spearman相关分析显示,血清E_(2)、T水平与FSS评分呈负相关,血清Cys-C、CRP水平与FSS评分呈正相关(P<0.05);ROC曲线结果显示,血清E_(2)、T、Cys-C、CRP水平预测绝经后女性PSF发生的AUC分别为0.829、0.795、0.788、0.852;Logistic回归分析显示,血清E_(2)≤74.52 pmol/L、T≤0.815 nmol/L、Cys-C≥1.715 mg/L、CRP≥10.74 mg/L是绝经后女性PSF发生的独立危险因素(P<0.05)。结论绝经后女性PSF与血清性激素E_(2)、T、Cys-C、CRP水平有密切的相关性,血清E_(2)、T、Cys-C、CRP水平变化是PSF发生的独立危险性因素,对PSF临床预测有一定的价值。 展开更多
关键词 脑梗死后疲劳 绝经后女性 性激素 cYS-c cRP
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UV-C对苹果采后炭疽病的控制 被引量:18
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作者 吴芳芳 郑有飞 +1 位作者 檀根甲 马千里 《农业环境科学学报》 CAS CSCD 北大核心 2006年第4期1081-1083,共3页
应用UV-C辐射强度和辐射时间的乘积确定照射剂量,在不同的UV-C辐射剂量下,设不同的接种时间和不同的贮存温度和光照条件,测定了苹果采后炭疽病的发病率和发病指数。结果表明,控制苹果采后炭疽病的最适UV-C照射剂量为7.5kJ·m-2。UV-... 应用UV-C辐射强度和辐射时间的乘积确定照射剂量,在不同的UV-C辐射剂量下,设不同的接种时间和不同的贮存温度和光照条件,测定了苹果采后炭疽病的发病率和发病指数。结果表明,控制苹果采后炭疽病的最适UV-C照射剂量为7.5kJ·m-2。UV-C照射2d后,人工接种发病指数最低,紫外照射结合13℃低温贮存,果实发病率、发病指数明显低于对照。低剂量UV-C照射能降低苹果炭疽病的发病率和发病指数,抑制苹果采后炭疽病的发生、发展。低剂量紫外线照射可诱导苹果的抗病性,且其诱导具有时间性。UV-C照射后光照与黑暗贮存控制炭疽病的效果差异不显著。 展开更多
关键词 UV—c 苹果 采后病害 苹果炭疽病菌
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3D-C/SiC的高温弯曲性能和后处理对弯曲性能的影响 被引量:9
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作者 乔生儒 李玫 +1 位作者 韩栋 张立同 《机械强度》 CAS CSCD 北大核心 2003年第5期495-498,共4页
3D C SiC用T3 0 0碳纤维编织为三维四向编织体 ,编织角 2 2°。CVI(chemicalvaporinfiltration)法致密 ,纤维体积分数 40 %~ 45 % ,热解碳界面层厚度约 0 .2微米、密度为 2 .0 1g cm3和空隙率为 17% ,最终在试样表面形成 5 0 μm的... 3D C SiC用T3 0 0碳纤维编织为三维四向编织体 ,编织角 2 2°。CVI(chemicalvaporinfiltration)法致密 ,纤维体积分数 40 %~ 45 % ,热解碳界面层厚度约 0 .2微米、密度为 2 .0 1g cm3和空隙率为 17% ,最终在试样表面形成 5 0 μm的SiC涂层。在YKM 2 2 0 0超高温试验机上进行三点弯曲试验 ,真空度为 10 - 3Pa ,夹头位移速率为 0 .5mm min。结果表明 ,随试验温度升高 ,弯曲强度在 90 0℃和 170 0℃出现了两个峰值 ;弯曲模量在 110 0℃出现了最大值 ;而弯曲应变在低于 15 0 0℃基本保持不变 ,高于 15 0 0℃不断升高 ,出现了明显的不可逆变性。试样 180 0℃真空保温 1小时后处理 ,弯曲模量明显降低和强度降低 ,而变形能力明显升高。激光拉曼分析得出 :制备的 3D C SiC碳纤维存在残余压应力 ,13 0 0℃处理后碳纤维存在残余拉应力 ,而 2 0 5 0℃处理后碳纤维没有残余应力。高温下因基体和纤维膨胀系数不同 ,易产生界面脱粘和分离 ,使得基体中的裂纹不易扩展到纤维中 ,保持了纤维强度 ,同时纤维易于滑动。这是很高温度下弯曲模量降低、变形能力增加和弯曲强度略增加的原因。 展开更多
关键词 高温 弯曲试验 后处理 残余应力 界面 弯曲性能 3D-c/SIc 复合材料
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一维C^1有限元超收敛解答计算的EEP法 被引量:17
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作者 袁驷 王枚 和雪峰 《工程力学》 EI CSCD 北大核心 2006年第2期1-9,共9页
将新近提出的C0有限元后处理中超收敛解答计算的单元能量投影(Element Energy Projection,简称EEP)法推广到一维C1类有限元。根据单元投影定理具体推导了一般梁单元的计算公式,并对两个有代表性的单元给出了数值算例。分析和算例表明,EE... 将新近提出的C0有限元后处理中超收敛解答计算的单元能量投影(Element Energy Projection,简称EEP)法推广到一维C1类有限元。根据单元投影定理具体推导了一般梁单元的计算公式,并对两个有代表性的单元给出了数值算例。分析和算例表明,EEP法在一维C1类有限元中再次获得令人满意的效果,即对任一单元中的任一点,从位移一直到三阶导数(如梁的挠度、转角、弯矩、剪力),匀可获得与结点位移精度相当的超收敛结果,而且可精确满足自然边界条件。 展开更多
关键词 有限元 一维c^1问题 后处理 超收敛 单元能量投影
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采后UV-C辐照对马铃薯干腐病的抑制效应及相关酶活性的影响 被引量:4
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作者 余斌 南运有 +3 位作者 孔娜娜 党仁美 拜占玲 刘娟 《核农学报》 CAS CSCD 北大核心 2017年第9期1730-1736,共7页
为探讨不同辐照剂量的短波紫外线(UV-C)处理对马铃薯干腐病的抑制作用及相关酶活性的影响,以贮藏期间的马铃薯块茎为材料,经剂量为0、5、15、25、35、45 kJ·m-2的UV-C辐照,研究分析经损伤接菌后马铃薯块茎干腐病病斑及相关防御性酶... 为探讨不同辐照剂量的短波紫外线(UV-C)处理对马铃薯干腐病的抑制作用及相关酶活性的影响,以贮藏期间的马铃薯块茎为材料,经剂量为0、5、15、25、35、45 kJ·m-2的UV-C辐照,研究分析经损伤接菌后马铃薯块茎干腐病病斑及相关防御性酶[过氧化氢酶(CAT)、过氧化物酶(POD)、苯丙氨酸解氨酶(PAL)、丙二醛(MDA)]的变化情况。结果表明,损伤接菌后的马铃薯块茎,经剂量5~45 kJ·m^(-2)的UV-C辐照处理,块茎中MDA、PAL活性均显著降低,POD活性显著升高;剂量5 kJ·m^(-2)的辐照处理可显著提高损伤接菌后的马铃薯块茎中CAT活性;剂量5~45 kJ·m^(-2)的辐照处理均可有效抑制马铃薯块茎病斑直径的扩散,其中以35 kJ·m^(-2)处理效果最佳。本研究证实UV-C辐照有助于提高贮藏期间马铃薯块茎对于干腐病的抗性,为利用UV-C这种新型环保的马铃薯贮藏方法提供了理论参考。 展开更多
关键词 短波紫外线 马铃薯块茎 采后 干腐病 相关酶活性
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后置缺氧UCT分段进水工艺处理低C/N城市污水 被引量:14
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作者 王慰 王淑莹 +3 位作者 张琼 邢立群 鲍方博 彭永臻 《中国环境科学》 EI CAS CSCD 北大核心 2016年第7期1997-2005,共9页
为处理低碳源生活污水,以内碳源反硝化途径为出发点,开发了后置缺氧UCT分段进水工艺.该工艺仅在UCT分段进水最后一好氧段末端增加了后置缺氧环节,以强化微生物内碳源储存能力.在低C/N水平(平均进水C/N=3.1±1.5)的生活污水条件下,... 为处理低碳源生活污水,以内碳源反硝化途径为出发点,开发了后置缺氧UCT分段进水工艺.该工艺仅在UCT分段进水最后一好氧段末端增加了后置缺氧环节,以强化微生物内碳源储存能力.在低C/N水平(平均进水C/N=3.1±1.5)的生活污水条件下,后置缺氧UCT分段进水工艺实现了平均75.3%的TN去除率,运行61d后同步硝化反硝化去除的氮量高达31.5%;运行40d后污泥内碳源储存水平比原工艺污泥提高12.2%,9小时比内源反硝化速率由零提高至5.56mg N/(g VSS?d),系统可通过好氧段同步硝化内源反硝化(SNED)提高TN去除率.污泥沉降性能有明显改善:SVI值由350m L/g降至97m L/g,而原UCT分段进水工艺污泥仍然膨胀.该工艺仅在原工艺基础上增加了一后置缺氧段,无需外加碳源和额外硝化液回流设施,有利于水厂升级改造. 展开更多
关键词 UcT 分段进水 后置缺氧 c/N 内碳源反硝化
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