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Novel fuzzy uncertainty modeling for land cover classification based on clustering analysis
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作者 Hui HE Haihua XING +1 位作者 Dan HU Xianchuan YU 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2019年第2期438-450,共13页
It is well known that there is a degree of fuzzy uncertainty in land cover classification using remote sensing (RS) images. In this article, we propose a novel fuzzy uncertainty modeling algorithm for representing the... It is well known that there is a degree of fuzzy uncertainty in land cover classification using remote sensing (RS) images. In this article, we propose a novel fuzzy uncertainty modeling algorithm for representing the features of land cover patterns, and present an adaptive interval type-2 fuzzy clustering method. The proposed fuzzy uncertainty modeling method is performed in two main phases. First, the segmentation units of the input multi-spectral RS image data are subjected to objectbased interval-valued symbolic modeling. As a result, features for each land cover type are represented in the form of an intervalvalued symbolic vector, which describes the intra-class uncertainty better than the source data and improves the separability between different classes. Second, interval type-2 fuzzy sets are generated for each cluster based on the distance metric of the interval-valued vectors. This step characterizes the inter-class high-order fuzzy uncertainty and improves the classification accuracy. To demonstrate the advantages and effectiveness of the proposed approach, extensive experiments are conducted on two multispectral RS image datasets from regions with complex land cover characteristics, and the results are compared with those given by well-known fuzzy and conventional clustering algorithms. 展开更多
关键词 Interval-valued data Type-2 FUZZY SETS Type REDUCTION Type-2 FUZZY CLUSTERING LAND COVER classification
活血通腑方对大鼠术后腹腔粘连巨噬细胞细胞因子的影响 预览
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作者 王雅洁 李文林 +6 位作者 连紫宇 马妍婷 赵敏 杨丽丽 唐升进 王叶同 曾莉 《中国老年学杂志》 CAS 北大核心 2019年第5期1135-1139,共5页
目的探讨活血通腑方对大鼠术后腹腔粘连部位白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、精氨酸酶(Arg)-1 m RNA及IL-1、IL-6、TNF-α、IL-4、IL-10、IL-13等细胞因子的影响。方法雄性SD大鼠40只采用拙刀法建立腹腔粘连模型,分为模型组、... 目的探讨活血通腑方对大鼠术后腹腔粘连部位白细胞介素(IL)-6、肿瘤坏死因子(TNF)-α、精氨酸酶(Arg)-1 m RNA及IL-1、IL-6、TNF-α、IL-4、IL-10、IL-13等细胞因子的影响。方法雄性SD大鼠40只采用拙刀法建立腹腔粘连模型,分为模型组、四磨汤组、氟伐他汀组、活血通腑方组各10只,另10只为假手术组。通过粘连评分评价腹腔粘连水平,实时荧光定量聚合酶链反应(RT-PCR)检测IL-6、TNF-α、Arg-1 m RNA表达水平及酶联免疫吸附试验检测IL-1、IL-6、TNF-α、IL-4、IL-10、IL-13细胞因子含量。结果与模型组相比,四磨汤组、氟伐他汀组及活血通腑方组的粘连评分均有不同程度的减轻(P<0. 05,P<0. 01),其中活血通腑方组和四靡汤组粘连评分降低显著(P<0. 01);显著降低IL-6、TNF-α、Arg-1 m RNA表达水平及减少IL-1、IL-6、TNF-α细胞因子含量(P<0. 05);显著提高IL-4、IL-10、IL-13细胞因子含量(P<0. 05)。结论活血通腑方对大鼠术后腹腔粘连具有抑制作用,可能是通过调控巨噬细胞含量达到防治术后腹腔粘连的作用。 展开更多
关键词 活血通腑方 腹腔粘连 巨噬细胞 经典活化型 替代活化型
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Prevention of macrovascular complications in patients with type 2 diabetes mellitus: Review of cardiovascular safety and efficacy of newer diabetes medications 预览
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作者 Ravi Kant Kashif M Munir +1 位作者 Arshpreet Kaur Vipin Verma 《世界糖尿病杂志:英文版(电子版)》 2019年第6期324-332,共9页
Lack of conclusive beneficial effects of strict glycemic control on macrovascular complications has been very frustrating for clinicians involved in care of patients with diabetes mellitus (DM). Highly publicized cont... Lack of conclusive beneficial effects of strict glycemic control on macrovascular complications has been very frustrating for clinicians involved in care of patients with diabetes mellitus (DM). Highly publicized controversy surrounding cardiovascular (CV) safety of rosiglitazone resulted in major changes in United States Food and Drug Administration policy in 2008 regarding approval process of new antidiabetic medications, which has resulted in revolutionary data from several large CV outcome trials over the last few years. All drugs in glucagon-like peptide-1 receptor agonist (GLP-1 RA) and sodium-glucose cotransporter-2 (SGLT-2) inhibitor classes have shown to be CV safe with heterogeneous results on CV efficacy. Given twofold higher CV disease mortality in patients with DM than without DM, GLP-1 RAs and SGLT-2-inhibitors are important additions to clinician’s armamentarium and should be second line-therapy particularly in patients with T2DM and established atherosclerotic CV disease or high risks for CV disease. Abundance of data and heterogeneity in CV outcome trials results can make it difficult for clinicians, particularly primary care physicians, to stay updated with all the recent evidence. The scope of this comprehensive review will focus on all major CV outcome studies evaluating CV safety and efficacy of GLP-1 RAs and SGLT-2 inhibitors. 展开更多
关键词 Newer antidiabetic MEDICATIONS Glucagon-like peptide-1 receptor agonist Sodium-glucose cotransporter-2 inhibitors Type 2 DIABETES MELLITUS Macrovascular complications CARDIOVASCULAR outcome trials Major CARDIOVASCULAR events HEART failure PREVENTION of HEART disease
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G protein-coupled receptor kinase 2 inhibition improves erectile function through amelioration of endothelial dysfunction and oxidative stress in a rat model of type 2 diabetes
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作者 Zhi-Hua Wan Yuan-Jie Zhang +4 位作者 Lin Chen Yong-Lian Guo Guo-Hao Li Ding Wu Yong Wang 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第1期74-79,共6页
Type 2 diabetes mellitus (T2DM)is a common cause of erectile dysfunction (ED).It has been demonstrated that G protein-coupled receptor kinase 2 (GRK2)overexpression contributes to diabetic endothelial dysfunction and ... Type 2 diabetes mellitus (T2DM)is a common cause of erectile dysfunction (ED).It has been demonstrated that G protein-coupled receptor kinase 2 (GRK2)overexpression contributes to diabetic endothelial dysfunction and oxidative stress,which also underlies ED in T2DM.We hypothesized that GRK2 overexpressed and attenuated endothelial function of the cavernosal tissue in a rat model of T2DM.T2DM rats were established by feeding with a high-fat diet (HFD)for 2 weeks and then administering two intraperitoneal (IP) injections of a low dose of streptozotocin (STZ),followed by continuous feeding with a HFD for 6 weeks.GRK2 was inhibited by IP injection of paroxetine,a selective GRK2 inhibitor,after STZ injection.Insulin challenge tests,intracavernous pressure (ICP), GRK2 expression,the protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS)pathway,nicotinamide adenine dinucleotide phosphate (NADPH)oxidase subunit gp91phox,nitric oxide (NO),reactive oxygen species (ROS)production,and apoptosis in cavernosal tissue were examined.Less response to insulin injection was observed in T2DM rats 2 weeks after HFD.Markedly increased GRK2 expression,along with impaired Akt/eNOS pathway,reduced NO production,increased gp91phox expression and ROS generation,increased apoptosis and impaired erectile function were found in T2DM rats.inhibition of GRK2 with paroxetine ameliorated Akt/eNOS signaling,restored NO production,downregulated NADPH oxidase,subsequently inhibited ROS generation and apoptosis,and ultimately preserved erectile function.These results indicated that GRK2 upregulation may be an important mechanism underlying T2DM ED,and GRK2 inhibition may be a potential therapeutic strategy for T2DM ED. 展开更多
关键词 ENDOTHELIAL DYSFUNCTION erectile DYSFUNCTION G protein-coupled receptor KINASE 2 oxidative stress type 2 diabetes MELLITUS
SGLT-2 inhibitors in non-alcoholic fatty liver disease patients with type 2 diabetes mellitus:A systematic review 预览
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作者 Henith Raj Harsh Durgia +4 位作者 Rajan Palui Sadishkumar Kamalanathan Sandhiya Selvarajan Sitanshu Sekhar Kar Jayaprakash Sahoo 《世界糖尿病杂志:英文版(电子版)》 2019年第2期114-132,共19页
BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is a common comorbidity with type 2 diabetes.The existing therapeutic options for NAFLD are not adequate.Hypocaloric diet and exercise is the cornerstone of therapy i... BACKGROUND Non-alcoholic fatty liver disease(NAFLD)is a common comorbidity with type 2 diabetes.The existing therapeutic options for NAFLD are not adequate.Hypocaloric diet and exercise is the cornerstone of therapy in NAFLD.Pioglitazone is the only drug recommended in diabetes patients with biopsy proven non-alcoholic steatohepatitis.The frequent coexistence of NAFLD and type 2 diabetes with their combined adverse health consequences and inadequate therapeutic options makes it necessary to search for newer alternatives.AIM To assess the effect of sodium glucose cotransporter-2(SGLT-2)inhibitors on liver enzymes in type 2 diabetes patients with NAFLD.METHODS We searched PubMed/MEDLINE,Cochrane library,Google scholar,and Clinicaltrials.gov for the relevant articles to be included in this systematic review.Human studies done in type 2 diabetes patients with NAFLD treated with SGLT-2 inhibitors for at least 12 wk were included.Data from eight studies(four randomised controlled trials and four observational studies)were extracted and a narrative synthesis was done.A total of 214 patients were treated with SGLT-2 inhibitors in these studies(94 in randomised controlled trials and 120 in observational studies).RESULTS The primary outcome measure was change in serum alanine aminotransferase level.Out of eight studies,seven studies showed a significant decrease in serum alanine aminotransferase level.Most of the studies revealed reduction in serum level of other liver enzymes like aspartate aminotransferase and gamma glutamyl transferase.Five studies that reported a change in hepatic fat exhibited a significant reduction in hepatic fat content in those treated with SGLT-2 inhibitors.Likewise,among the three studies that evaluated a change in indices of hepatic fibrosis,two studies revealed a significant improvement in liver fibrosis.Moreover,there was an improvement in obesity,insulin resistance,glycaemia,and lipid parameters in those subjects taking SGLT-2 inhibitors.The studies disclosed that about 17%(30/176)of the sub 展开更多
关键词 Alanine AMINOTRANSFERASE HEPATIC fat HEPATIC fibrosis Non-alcoholic fatty liver disease Sodium-glucose cotransporter-2 inhibitor Type 2 diabetes MELLITUS
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NET1和CITED2在胃癌中的表达及临床意义 预览
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作者 欧阳德亮 刘龙飞 +2 位作者 王丽萍 黄明明 肖建虹 《当代医学》 2019年第10期109-112,共4页
目的探讨NET1、CITED2在胃癌组织以及胃癌细胞中的表达情况,并进一步明确其与不同临床病理特征之间的相关性。方法收集56例胃癌患者手术切除的肿瘤组织样本,同时收集癌旁组织样本以及正常胃组织样本作为对照,采用qRT-PCR检测其中NET1、C... 目的探讨NET1、CITED2在胃癌组织以及胃癌细胞中的表达情况,并进一步明确其与不同临床病理特征之间的相关性。方法收集56例胃癌患者手术切除的肿瘤组织样本,同时收集癌旁组织样本以及正常胃组织样本作为对照,采用qRT-PCR检测其中NET1、CITED2的表达水平;同时通过qRT-PCR检测不同癌细胞株以及正常胃黏膜上皮细胞中NET1、CITED2的表达水平;Pearson相关分析评估NET1、CITED2与临床病理特征的关系。结果胃癌组织中NET1、CITED2的表达水平显著高于癌旁组织与正常组织(P<0.01),而胃癌细胞株BCG-823、MKN-28、SGC-7901以及ASG中NET1、CITED2的表达水平均显著高于正常胃黏膜细胞GES-1(P<0.05);NET1、CITED2表达水平与肿瘤分化程度呈负相关,与淋巴结转移、肿瘤侵袭深度以及TMN分期呈正相关,而与年龄、性别、肿瘤的大小以及位置无明显相关性。结论NET1、CITED2在胃癌组织以及胃癌细胞中均为高表达,同时与胃癌患者的部分临床病理特征存在相关性,提示NET1、CITED2为临床预防治疗胃癌的潜在靶点。 展开更多
关键词 NET1 CITED2 胃肿瘤
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Neuroprotection mediated by the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage 预览
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作者 Yang Wang De-Jun Bao +4 位作者 Bin Xu Chuan-Dong Cheng Yong-Fei Dong Xiang-pin Wei Chao-Shi Niu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期1013-1024,共12页
The Wnt/Frizzled signaling pathway participates in many inflammation-linked diseases.However,the inflammatory response mediated by the Wnt/Frizzled signaling pathway in experimental subarachnoid hemorrhage has not bee... The Wnt/Frizzled signaling pathway participates in many inflammation-linked diseases.However,the inflammatory response mediated by the Wnt/Frizzled signaling pathway in experimental subarachnoid hemorrhage has not been thoroughly investigated.Consequently,in this study,we examined the potential role of the Wnt/Frizzled signaling pathway in early brain injury in rat models of subarachnoid hemorrhage.Simultaneously,possible neuroprotective mechanisms were also investigated.Experimental subarachnoid hemorrhage rat models were induced by injecting autologous blood into the prechiasmatic cistern.Experiment 1 was designed to examine expression of the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage.In total,42 adult rats were divided into sham(injection of equivalent volume of saline),6-,12-,24-,48-,72-hour,and 1-week subarachnoid hemorrhage groups.Experiment 2 was designed to examine neuroprotective mechanisms of the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage.Rats were treated with recombinant human Wnt1(rhwnt1),small interfering Wnt1(siwnt1)RNA,and monoclonal antibody of Frizzled1(anti-Frizzled1)at 48 hours after subarachnoid hemorrhage.Expression levels of Wnt1,Frizzled1,β-catenin,peroxisome proliferator-activated receptor-γ,CD36,and active nuclear factor-κB were examined by western blot assay and immunofluorescence staining.Microglia type conversion and inflammatory cytokine levels in brain tissue were examined by immunofluorescence staining and enzyme-linked immunosorbent assay.Our results show that compared with the sham group,expression levels of Wnt1,Frizzled1,andβ-catenin were low and reduced to a minimum at 48 hours,gradually returning to baseline at 1 week after subarachnoid hemorrhage.rhwnt1 treatment markedly increased Wnt1 expression and alleviated subarachnoid hemorrhage-induced early brain injury(within 72 hours),including cortical cell apoptosis,brain edema,and neurobehavioral deficits,accompanied by increasing prot 展开更多
关键词 nerve REGENERATION SUBARACHNOID hemorrhage Wnt/Frizzled signaling pathway early brain injury nuclear factor-κB M2 type MICROGLIA PEROXISOME proliferator-activated receptor-γ inflammatory cytokines neural REGENERATION
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Mechanisms by which fibroblast growth factor 20 improves motor performance in a mouse model of Parkinson's disease 预览
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作者 Ai-Qin Wang Li-Na Kong +3 位作者 Ming-Zhu Meng Xiu-He Zhao Si Chen Xiao-Tang Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第8期1438-1444,共7页
Genome-wide studies have reported that Parkinson's disease is associated with abnormal expression of various growth factors. In this study, male C57BL/6 mice aged 10 weeks were used to establish Parkinson's di... Genome-wide studies have reported that Parkinson's disease is associated with abnormal expression of various growth factors. In this study, male C57BL/6 mice aged 10 weeks were used to establish Parkinson's disease models using an intraperitoneal injection of 60 mg/kg 1-methyl- 4-phenyl-1,2,3,6-tetrahydropyridine. 28 days later, 10 or 100 ng fibroblast growth factor 20 was injected intracerebroventricularly. The electrophysiological changes in the mouse hippocampus were recorded using a full-cell patch clamp. Expression of Kv4.2 in the substantia nigra was analyzed using a western blot assay. Serum malondialdehyde levels were analyzed by enzyme-linked immunosorbent assay. The motor coordination of mice was evaluated using the rotarod test. The results showed that fibroblast growth factor 20 decreased A-type potassium current in neurons of the substantia nigra, increased long-term potentiation amplitude in the hippocampus, and downregulated Kv4.2 expression. A high dose of fibroblast growth factor 20 reduced serum malondialdehyde levels and enhanced the motor coordination of mice. These findings confirm that fibroblast growth factor 20 has a therapeutic effect on the toxicity induced by l-methyl-4-phenyl-l,2,3s6-tetrahydropyridine, and its mechanism of action is associated with the inhibition of A-type K^+ currents and Kv4.2 expression. All animal procedures were approved by the Animal Care and Use Committee of Qilu Hospital of Shandong University, China in 2017 (approval No. KYLL-2017-0012). 展开更多
关键词 nerve REGENERATION Parkinson's disease l-methyl-4-phenyl-1 2 3 6-tetrahydropyridine fibroblast growth factor 20 A-TYPE potassium current long-term POTENTIATION KV4.2 oxidative stress MALONDIALDEHYDE motor performance neural REGENERATION
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复杂孔隙储层三维岩石物理模版 预览
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作者 李宏兵 张佳佳 +1 位作者 蔡生娟 潘豪杰 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2019年第7期2711-2723,共13页
复杂孔隙储层往往同时发育孔缝洞等多种孔隙类型,这种孔隙结构的复杂性使得岩石的速度与孔隙度之间的相关性很差.经典的二维岩石物理模版只研究弹性参数与孔隙度和饱和度之间的定量关系,而不考虑孔隙结构的影响,用这样的模版来预测复杂... 复杂孔隙储层往往同时发育孔缝洞等多种孔隙类型,这种孔隙结构的复杂性使得岩石的速度与孔隙度之间的相关性很差.经典的二维岩石物理模版只研究弹性参数与孔隙度和饱和度之间的定量关系,而不考虑孔隙结构的影响,用这样的模版来预测复杂孔隙储层的物性参数时带来很大偏差.本文首先证明多重孔隙岩石的干骨架弹性参数可以用一个等效孔隙纵横比的单重孔隙岩石物理模型来模拟;进而基于等效介质岩石物理理论和Gassmann方程,建立一个全新的三维岩石物理模版,用它来建立复杂孔隙岩石的弹性性质与孔隙扁度及孔隙度和饱和度之间的定量关系;在此基础上,预测复杂储层的孔隙扁度、孔隙度以及孔隙中所包含的流体饱和度.实际测井和地震反演数据试验表明,三维岩石物理模版可有效提高复杂孔隙储层参数的预测精度. 展开更多
关键词 岩石物理模版 二维 三维 孔隙类型 物性参数 定量预测
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维生素D2对2型糖尿病周围神经病变治疗效果的多中心随机单盲干预研究
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作者 郑月月 柳德学 +2 位作者 石小霞 徐娜 李瑞阁 《中国慢性病预防与控制》 CAS 北大核心 2018年第7期495-499,共5页
目的探讨维生素D2(VD2)对2型糖尿病周围神经病变(DPN)的疗效,为DPN的临床治疗提供依据。方法于2012年3月至2014年12月在河南省南阳市3家医院选取320例DPN患者为研究对象,随机分为对照组和联合治疗组,各160例,进行多中心、随机单盲... 目的探讨维生素D2(VD2)对2型糖尿病周围神经病变(DPN)的疗效,为DPN的临床治疗提供依据。方法于2012年3月至2014年12月在河南省南阳市3家医院选取320例DPN患者为研究对象,随机分为对照组和联合治疗组,各160例,进行多中心、随机单盲、安慰剂对照干预研究。两组患者均给予基础治疗,同时联合治疗组肌肉注射VD25 000 IU/kg,对照组给予安慰剂,每2周1次,疗程为3个月,治疗结束后1年为临床终点。观察两组患者治疗有效率、周围神经传导速度(NCV)变化、NCV达标率、维生素D(VD)缺乏率、糖化血红蛋白(Hb A1C)、25羟维生素D3[25(OH)D3]浓度和多伦多症状总评分(TSS),比较对照组与联合治疗组治疗结束时及治疗结束1年后的疗效。采用SPSS 19.0软件进行t检验、χ-2检验和秩和检验。结果 298例DPN患者完成本次研究,其中对照组为154例,联合治疗组为144例。治疗结束时及结束1年后,联合治疗组治疗有效率(分别为75.0%、64.6%)均高于对照组(分别为61.7%、37.7%),差异均有统计学意义(P〈0.05,P〈0.01);治疗结束时,两组患者Hb A1C下降值比较,差异无统计学意义(P〉0.05),治疗结束1年后,联合治疗组Hb A1C下降值高于对照组,差异有统计学意义(P〈0.01);治疗结束时及治疗结束1年后,联合治疗组25(OH)D3浓度均显著高于对照组,VD缺乏率低于对照组,TSS下降值高于对照组,腓总神经、胫后神经及腓肠神经传导速度提高值均高于对照组,差异均有统计学意义(P〈0.01);治疗结束时,两组患者神经传导速度达标率比较,差异无统计学意义(P〉0.05),治疗结束1年后,联合治疗组神经传导速度达标率高于对照组,差异有统计学意义(P〈0.05)。联合治疗组不良反应发生率为2.1%,对照组无不良反应发生。结论 2型糖尿病并发DPN患者通过短期肌肉注射VD2可改善患者VD营养状况、临床症状和周围 展开更多
关键词 维生素D2 糖尿病 2 周围神经病变 神经传导速度
Type C Gen2对绞线的线缆设计 预览
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作者 林清寿 李必禄 何小明 《通信技术》 2018年第11期2777-2782,共6页
为了便于实际项目需要,设计了一种采用对绞线结构且带有E—Marker芯片的全功能USBType—C高速电缆。采用polar SI 9000仿真软件对整条Type C线缆链路按产品实际制程的要求进行阻抗模拟仿真,得出Type C整条链路阻抗的曲线。实验结果表... 为了便于实际项目需要,设计了一种采用对绞线结构且带有E—Marker芯片的全功能USBType—C高速电缆。采用polar SI 9000仿真软件对整条Type C线缆链路按产品实际制程的要求进行阻抗模拟仿真,得出Type C整条链路阻抗的曲线。实验结果表明,Type C整条链路阻抗一致性越好,其IMR、IRL性能就越好。采用一种新的线夹工艺,解决在Type C接头外模尺寸不变的情况下Type C Gen2SI性能及可制造的问题。实验证明,通过这种新的线夹工艺,不但可以解决困扰Type C SI性能的串扰难点,还可以解决可制造问题。目前,采用该设计方案的Type C线缆已拿到USB协会的1MType C Gen2证书。 展开更多
关键词 TYPE C 对绞线 GEN 2 串扰 可制造性
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钯催化的分子内Wacker-Type反应制备1,2-二氢喹啉衍生物 预览
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作者 张金刚 李云艺 +1 位作者 吴正兴 张万斌 《华东理工大学学报:自然科学版》 CSCD 北大核心 2018年第6期816-822,838共8页
1,2-二氢喹啉骨架结构在合成中间体和药物分子中具有广泛的应用。以邻位有端位烯烃取代的苯胺化合物为底物,应用过渡金属钯催化的Wacker-type反应及烯烃的异构化过程合成了一系列1,2-二氢喹啉衍生物。对苯环上不同位置或不同基团取代的... 1,2-二氢喹啉骨架结构在合成中间体和药物分子中具有广泛的应用。以邻位有端位烯烃取代的苯胺化合物为底物,应用过渡金属钯催化的Wacker-type反应及烯烃的异构化过程合成了一系列1,2-二氢喹啉衍生物。对苯环上不同位置或不同基团取代的底物,反应都可以顺利进行,而且对大部分底物都可以高产率得到相应的1,2-二氢喹啉产物。 展开更多
关键词 分子内 Wacker-type 1 2-二氢喹啉
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利拉鲁肽对2型糖尿病大鼠心肌组织转化生长因子-β1、Ⅰ型胶原蛋白表达的影响
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作者 吴振华 刘晶 +2 位作者 高晓芳 田佳 李兴 《中华糖尿病杂志》 CAS CSCD 北大核心 2018年第9期611-616,共6页
目的观察不同剂量利拉鲁肽对2型糖尿病(T2DM)大鼠心肌组织转化生长因子-B1(TGF-β1)、I型胶原蛋白(Col-β1)表达的影响并探讨其作用机制。方法选用4周龄、体重(200±20)g的健康雄性SD大鼠40只,采用随机数字表法分为正常对... 目的观察不同剂量利拉鲁肽对2型糖尿病(T2DM)大鼠心肌组织转化生长因子-B1(TGF-β1)、I型胶原蛋白(Col-β1)表达的影响并探讨其作用机制。方法选用4周龄、体重(200±20)g的健康雄性SD大鼠40只,采用随机数字表法分为正常对照组(N组,10只)和造模组(30只),造模组给予高糖、高脂饲料喂养8周后,-次性腹腔内推注l%链脲佐菌素(STZ)30mg/kg,成模后剩余22只再分为3组:T2DM组(D组,8只)、低剂量干预组(LD组,7只)和高剂量干预组(LG组,7只),LD组和LG组分别予腹腔注射利拉鲁肽50、200μ/kg,2次/d,D组予等量生理盐水。8周末,所有大鼠称体重,麻醉后采血测血糖、血脂等生化指标,留取心肌组织,行HE染色后光学显微镜下观察其病变,并采用免疫组化法测量TGF-B1和C01-1的表达,采用实时荧光定量聚合酶链反应(RT-PCR)法测量TGF.B1和Col-1mRNA的表达。组间数据比较采用单因素方差分析,两两比较采用LSD-t检验。结果(1)与N组相比,D组大鼠心肌细胞及其间质胶原纤维散在分布、排列紊乱,TGF-131、Col-1mRNA含量明显升高(分别为0.90±0.23比0.18±0.06、2.63±1.84比0.52±0.11,t=19.108、22.779,均P〈0.05)。(2)与D组相比,LD、LG组心肌纤维化程度减轻,TGF-131、Col-1mRNA含量降低(LD组分别为0.46±0.13比0.90±0.23、1.43±0.32比2.63±1.84,t=21.135、23.548;LG组分别为0.29±0.06比0.90+-0.23、0.89±0.12比2.63±1.84,t=18.398、20.159,均P〈0.05),且上述改变存在剂量依赖性。结论利拉鲁肽可能通过下调TGF-β1来抑制其纤维化通路下游Col-1的生成,发挥抗心肌组织纤维化的作用,延缓T2DM大鼠心肌病变的发生、发展。 展开更多
关键词 糖尿病 2 糖尿病心肌病 胰高血糖素样肽1 胶原蛋白 I型 转化生长 因子β1
Circulating microRNAs as biomarkers for diabetic neuropathy:A novel approach 预览
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作者 Eleni Xourgia Athanasia Papazafiropoulou Andreas Melidonis 《世界实验医学杂志》 2018年第3期18-23,共6页
Oxidative stress stemming from tissue exposure to constant hyperglycemia is one of the major pathogenetic pathways of diabetic macro-and microvascular complications.Diabetic polyneuropathy,commonly manifesting as dist... Oxidative stress stemming from tissue exposure to constant hyperglycemia is one of the major pathogenetic pathways of diabetic macro-and microvascular complications.Diabetic polyneuropathy,commonly manifesting as distal,symmetrical sensorimotor polyneuropathy,is characterized by progressive severity of symptoms,with rates analogous to the quality of glycemic control achieved by the patients and physicians.Palliative care with analgesics and aggressive glycemic control often improve quality of life in the absence of causative treatment.Currently,there is a growing body of evidence indicating the role of microRNAs in the pathogenesis of diabetic complications,with emphasis on diabetic nephropathy and neuropathy.Therefore,in this review,we aim to explore the role of microRNAs and their polymorphisms in the pathophysiology of diabetic polyneuropathy,as well as,the possibility of novel diagnostic and therapeutic applications by epigenetic profiling and manipulation. 展开更多
关键词 DIABETIC NEUROPATHY TYPE 2 DIABETES MELLITUS TYPE 1 DIABETES MELLITUS EPIGENETIC MicroRNAs
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环氧化酶-2水平和脂代谢指标在糖尿病心肌病患者体内的变化特点及意义 预览
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作者 杨俊 曾俊 +3 位作者 王稳 代敏 陈芳媛 杨建明 《中国临床保健杂志》 CAS 2018年第6期764-767,共4页
目的研究环氧化酶-2(COX-2)水平和脂代谢指标在糖尿病心肌病患者体内变化特点及意义。方法选取46例糖尿病心肌病患者设为观察组,选取同期单纯糖尿病患者40例设为对照组。记录并比较两组患者血脂指标、B型脑钠肽(BNP)、COX-2、血管紧张... 目的研究环氧化酶-2(COX-2)水平和脂代谢指标在糖尿病心肌病患者体内变化特点及意义。方法选取46例糖尿病心肌病患者设为观察组,选取同期单纯糖尿病患者40例设为对照组。记录并比较两组患者血脂指标、B型脑钠肽(BNP)、COX-2、血管紧张素转移酶2(ACE2)、基质金属蛋白酶组织抑制剂-2(TIMP-2)、基质金属蛋白酶-1(MMP-1)水平及心功能指标。结果观察组患者病程长于对照组,总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、BNP、COX-2、ACE2、TIMP-2、肌酸激酶同工酶(CK-MB)水平高于对照组,高密度脂蛋白胆固醇(HDL-C)、MMP-1、左室射血分数(LVEF)、E峰/A峰比值水平低于对照组,差异有统计学意义(P<0.05)。结论糖尿病心肌病患者体内BNP、COX-2、ACE2、TIMP-2水平显著上升,心功能指标下降,且脂代谢指标改变较为明显,为临床诊断糖尿病心肌病提供参考。 展开更多
关键词 糖尿病心肌病 环氧化酶2 血脂异常 利钠肽 C型
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Detection and significance of blood rheology and coagulation function index in elderly patients with type 2 diabetes mellitus complicated with cerebral infarction
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作者 Ming-Quan Liu Min Yang +2 位作者 Fei Huang Xue Yuan Jing Fan 《海南医科大学学报(英文版)》 2018年第1期133-136,共4页
Objective: To investigate the level of blood rheology and coagulation function in elderly patients with type 2 diabetes mellitus (T2DM) and cerebral infarction and its significance. Methods: A total of 81 elderly pati... Objective: To investigate the level of blood rheology and coagulation function in elderly patients with type 2 diabetes mellitus (T2DM) and cerebral infarction and its significance. Methods: A total of 81 elderly patients with T2DM and cerebral infarction were selected as the observation group, 80 cases of T2DM patients without cerebral infarction were selected as T2DM group, and 80 healthy elderly people as control group. According to the Adama classification, the patients in the observation group were divided into three groups: lacunar infarction group (n=28), small infarction group (n=39) and large infarction group (n=14). The blood rheology and coagulation function indexes levels among the groups were compared. Results: The single factor variance analysis showed that the differences of the high shear whole blood viscosity, plasma viscosity, low shear whole blood viscosity, APTT, PT, FIB and D-D levels among the control group were significant, T2DM group and observation group were statistically significant. Compared with the control group, the high shear whole blood viscosity, plasma viscosity, low shear whole blood viscosity, FIB and D-D levels in the T2DM group and observation group were significantly increased, PT and APTT were decreased sharply, and in the observation group high shear whole blood viscosity, plasma viscosity, low shear whole blood viscosity, FIB and D-D levels were significantly higher than that of T2DM group APTT, and PT were significantly lower than those of T2DM group. Lacunar infarction group, small infarction group and large infarction group with increased infarct size, with high shear whole blood viscosity, plasma viscosity, low shear whole blood viscosity, FIB and D-D levels were significantly increased, while APTT and PT were significantly decreased. Conclusion: T2DM and cerebral infarction patients with abnormal blood rheology and coagulation function, the index examination has important clinical value for cerebral infarction area evaluation. 展开更多
关键词 2 type diabetes MELLITUS Cerebral INFARCTION Blood RHEOLOGY COAGULATION function DETECTION value
离子液体中阴阳离子的特性对其吸收二氧化硫的影响 预览
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作者 陈玲 赵倩 +3 位作者 汪洋 柴牧原 徐志勇 赵文波 《材料导报》 CSCD 北大核心 2018年第17期2949-2958,2968共11页
SO2是一种无色、有强烈刺激性气味的气体,弥散在空气中的SO2对人体健康、生态环境有着严重的危害,是导致空气质量不断恶化的主要大气污染物之一。人为造成的SO2污染物的主要来源有燃料燃烧、工业生产、交通运输等,其中燃料燃烧占70%。因... SO2是一种无色、有强烈刺激性气味的气体,弥散在空气中的SO2对人体健康、生态环境有着严重的危害,是导致空气质量不断恶化的主要大气污染物之一。人为造成的SO2污染物的主要来源有燃料燃烧、工业生产、交通运输等,其中燃料燃烧占70%。因此,削减和控制燃料燃烧所产生的SO2的排放是我国能源利用和环保领域的重要研究方向,烟气脱硫是应对烟气中SO2排放的有效途径。湿法烟气脱硫是目前应用最广泛的方法,占世界安装烟气脱硫机组总容量的85%,采用该方法处理的烟气占总处理量的80%。在湿法烟气脱硫技术中比较实用的主要包括钙法脱硫、有机胺脱硫、海水脱硫。其中,钙法脱硫的脱硫效率高,对煤种的适应性较强,但是脱硫会产生CaSO4沉淀,降低经济效益;有机胺脱硫的系统腐蚀性小,副产品可生产硫酸,但是胺易挥发,造成吸收剂损失和环境污染;海水法脱硫的工艺简单、运行可靠,但其应用受到地域的影响,并且对环境也会产生一定的影响。离子液体是一种新兴的绿色介质,它具有环保、可再生、结构可调控的优点,为解决传统工艺中的污染问题提供了新方案。在离子液体吸收气体的过程中,吸收液不会因其挥发性而蒸发进入气相,并且可以在较低的温度下完成吸收解吸循环。离子液体的这些优良特性使其在SO2吸收方面有着极广阔的应用前景。目前,研究者们已合成了一系列胍盐类、咪唑类、醇胺类、吡啶类等离子液体,探究其吸收SO2的性能与机理,并根据其结构可设计的特点,在离子液体中的阴阳离子上引入各类官能团(如氰基、醚基、氨基、卤素),合成满足特定需求的离子液体,使其高效、可逆、低耗地吸收SO2。本文总结了近年来各类离子液体吸收SO2的性能和机理,为系统地认识离子液体在SO2分离领域的应用提供了帮助;重点阐明了离子液体中阴阳离� 展开更多
关键词 离子液体 吸收 二氧化硫 阴阳离子 种类 酸碱性 官能化
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浅谈手机充电器的发展衍变和未来发展趋势 预览
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作者 郭修根 《电子世界》 2018年第19期110-113,共4页
本文阐述了手机充电器的发展衍变过程及未来的发展趋势。
关键词 手机充电器 快充 QC2.0 QC3.0 QC4.0 PD PPS type C 高通 联发科
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A peptide containing the receptor binding site of insulin-like growth factor binding protein-2 enhances bone mass in ovariectomized rats 预览
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作者 Gang Xi Christine Wai +1 位作者 Clifford J.Rosen David R.Clemmons 《骨研究:英文版》 SCIE CAS CSCD 2018年第3期280-288,共9页
Male Igfbp2./.mice have a significant reduction in bone mass and administration of a peptide that contains the insulin-like growth factor binding protein-2(IGFBP-2)receptor-binding domain stimulates bone formation in ... Male Igfbp2./.mice have a significant reduction in bone mass and administration of a peptide that contains the insulin-like growth factor binding protein-2(IGFBP-2)receptor-binding domain stimulates bone formation in these animals.Female Igfbp2./.mice do not have this phenotype but following ovariectomy(OVX)lose more bone than OVX wild-type mice.This suggests that in the absence of estrogen,IGFBP-2 is required to maintain bone mass.Therefore these studies were undertaken to determine if this peptide could stimulate bone acquisition in OVX rats.OVX rats were divided into seven treatment groups:sham animals,OVX animals,OVX animals receiving a control scrambled peptide,or one of three doses of the active peptide termed PEG-HBD-1(0.7,2,and 6 mg·kg-1)and an OVX group receiving parathyroid hormone(PTH)(50μg·kg-1 per day).The peptides were administered for 8 weeks.DXA revealed a significant reduction in femoral and tibial areal bone mineral density(aBMD)after OVX,whereas treatment with the high-dose peptide increased aBMD by 6.2%±2.4%(P<0.01)compared to control peptide;similar to the increase noted with PTH(5.6%±3.0%,P<0.01).Similar increases were noted with two lower doses of the peptide(3.8%±1.5%,P<0.05 for low dose;3.1%±1.6%,P=0.07 for middle dose).Micro CT showed that the OVX control peptide animals had reductions of 41%and 64%in femoral trabecular BV/TV and trabecular number,respectively.All three doses of the peptide increased bone volume/total volume(BV/TV)significantly,while the low and middle doses increased trabecular number.Cortical BV/TV and thickness at the midshaft increased significantly with each dose of peptide(18.9%±9.8%,P<0.01 and 14.2%±7.9%,P<0.01 for low dose;23.7%±10.7%,P<0.001 and 15.8%±6.1%,P<0.001 for middle dose;19.0%±6.9%,P<0.01 and 16.2%±9.7%,P<0.001 for high dose)and with PTH(25.8%±9.2%,P<0.001 and 19.4%±8.8%,P<0.001).Histomorphometry showed that the lowest dose of peptide stimulated BV/TV,trabecular thickness,mineral apposition rate(MAR),bone formation rate/bone surface(BFR/B 展开更多
关键词 INSULIN-LIKE growth factor BINDING protein-2 OVX WILD-TYPE mice
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QFSN型1260MW级二极发电机试验分析 预览
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作者 郑东平 唐强 杨昔科 《电机技术》 2018年第5期9-12,共4页
由上海发电机厂研制的首台QFSN型1260MW级二极发电机的全部工厂试验已于2017年结束,对该机的工厂型式试验结果与设计值进行了比较及分析,其各项主要技术指标均符合设计要求,性能优良、可靠。
关键词 二极1260Mw级发电机 水氢氢 型式试验
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