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The trend of change in catheter ablation versus antiarrhythmic drugs for the management of atrial fibrillation over time: a meta-analysis and meta-regression 预览
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作者 Wei LIU Qiang WU +1 位作者 Xiao-Jie YANG Jing Huang 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2018年第6期441-450,共10页
ObjectiveTo 在 time.MethodsThe 上与 atrial 纤维性颤动(AF ) 在病人为节奏控制与 antiarrhythmic 药治疗(ADT ) 相比在导管脱离的功效和安全评估变化的趋势联机数据库 PubMed 和 EMBASE 被在找相关研究。STATA 软件(版本 12.0 ) 被... ObjectiveTo 在 time.MethodsThe 上与 atrial 纤维性颤动(AF ) 在病人为节奏控制与 antiarrhythmic 药治疗(ADT ) 相比在导管脱离的功效和安全评估变化的趋势联机数据库 PubMed 和 EMBASE 被在找相关研究。STATA 软件(版本 12.0 ) 被用来执行元分析和 meta-regression.ResultsFifteen 包括有 AF 的 2249 个病人的使随机化的控制试用被识别。分享的结果证明那导管脱离与 ADT 相比在 AF 复发的风险与 52% 减小被联系[风险比率(RR )= 0.48, 95% 信心间隔(CI ) :0.40-0.57,我 <sup>2</sup>=70.7%) 。亚群分析证明那导管脱离在 2011 前与研究相比在 2011 以后在研究展出了更少的功效(RR = 0.61, 95% CI:0.54-0.68,我 <sup>2</sup>=9.3% 并且 RR = 0.34, 95% CI:0.24-0.47,我 <sup>2</sup>=69.9% ,分别地) ,并且安全结果更高显示出 1.08 褶层不利事件的发生(14.2% 对 7.3% ;RR = 1.08, 95% CI:1.04-1.13 ) 在在 2011 .ConclusionsCatheter 以后的研究,脱离看起来比为节奏控制的 ADT 优异。然而,更少的功效和不利事件的更高的率在 2011 前与研究相比在 2011 以后在研究被观察。 展开更多
关键词 纤维性 导管 回归 时间 颤动 管理 节奏控制 PUBMED
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现实核力Hartree-Fock Gamow基矢计算
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作者 吴强 许甫荣 《科学通报》 CSCD 北大核心 2018年第27期2876-2882,共7页
对远离稳定线弱束缚原子核性质的研究是当代核物理领域重要的热点之一.对于弱束缚核,如何自洽可靠地描述和处理束缚态和连续态之间的耦合是理论描述的关键问题,也是理论研究面临的一个挑战.一种较成功的方案是采用Gamow基,以相同的方式... 对远离稳定线弱束缚原子核性质的研究是当代核物理领域重要的热点之一.对于弱束缚核,如何自洽可靠地描述和处理束缚态和连续态之间的耦合是理论描述的关键问题,也是理论研究面临的一个挑战.一种较成功的方案是采用Gamow基,以相同的方式处理束缚态、共振态和散射态,来统一描述核结构和核反应性质.本文介绍了一种从现实核子-核子相互作用出发,从微观上自洽生成Hartree-Fock(HF)Gamow基的新方法.基于现实核力,首先在谐振子基下进行HF迭代,得到的HF势通过基转换解析延拓到复动量平面上,最后包含束缚态、共振态和散射态的Gamow基由求解复动量空间的HF方程得到.作为例子,基于手征核力N-3LO,核力利用V(low-k)方法重整化到动量截断Λ=2.1 fm^-1采用这种方法计算了-4He和^22O的HF单粒子共振态,并分析了计算的收敛性和有效性.还讨论了从散射态相移的计算得到共振态位置的方法,其得到^22O的单粒子共振态与复平面直接计算的结果一致.这种从现实核力得到HF Gamow基的方法计算量小,收敛快,得到的包含束缚态、共振态以及散射态的基,有望进一步应用于第一性原理的多体计算中来研究弱束缚核的性质. 展开更多
关键词 现实核力 共振态 连续谱 弱束缚
Boosting oxygen reduction activity of spinel CoFe2O4 by strong interaction with hierarchical nitrogen-doped carbon nanocages
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作者 Hao Fan Lijun Yang +7 位作者 Yu Wang Xiali Zhang Qingsong Wu Renchao Che Meng Liu Qiang Wu Xizhang Wang Zheng Hu 《科学通报:英文版》 SCIE EI CSCD 2017年第20期1365-1372,共8页
The unique hierarchical nitrogen-doped carbon nanocages(h NCNC) are used as a new support to homogeneously immobilize spinel Co Fe_2O_4 nanoparticles by a facile solvothermal method. The so-constructed hierarchical Co... The unique hierarchical nitrogen-doped carbon nanocages(h NCNC) are used as a new support to homogeneously immobilize spinel Co Fe_2O_4 nanoparticles by a facile solvothermal method. The so-constructed hierarchical Co Fe_2O_4/h NCNC catalyst exhibits a high oxygen reduction activity with an onset potential of0.966 V and half-wave potential of 0.819 V versus reversible hydrogen electrode, far superior to the corresponding 0.846 and 0.742 V for its counterpart of Co Fe_2O_4/h CNC with undoped hierarchical carbon nanocages(h CNC) as the support, which locates at the top level for spinel-based catalysts to date.Consequently, the Co Fe_2O_4/h NCNC displays the superior performance to the Co Fe_2O_4/h CNC, when used as the cathode catalysts in the home-made Al-air batteries. X-ray photoelectron spectroscopy characterizations reveal the more charge transfer from Co Fe_2O_4 to h NCNC than to h CNC, indicating the stronger interaction between Co Fe_2O_4 and h NCNC due to the nitrogen participation. The enhanced interaction and hierarchical morphology favor the high dispersion and modification of electronic states for the active species as well as the mass transport during the oxygen reduction process, which plays a significant role in boosting the electrocatalytic performances. In addition, we noticed the high sensitivity of O 1 s spectrum to the particle size and chemical environment for spinel oxides, which is used as an indicator to understand the evolution of ORR activities for all the Co Fe_2O_4-related contrast catalysts. Accordingly,the well-defined structure-performance relationship is demonstrated by the combination of experimental characterizations with theoretical calculations. This study provides a promising strategy to develop efficient, inexpensive and durable oxygen reduction electrocatalysts by tuning the interaction between spinel metal oxides and the carbon-based supports. 展开更多
MiR-200a and miR-200b target PTEN to regulate the endometrial cancer cell growth in vitro
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作者 Qiang Wu Ren-Lian Lu +1 位作者 Jing-Xiang Li Li-Jun Rong 《亚太热带医药杂志:英文版》 SCIE CAS 2017年第5期474-477,共4页
Objective:To study whether miR-200a and miR-200b target PTEN gene expression to regulate the endometrial cancer cell growth in vitro. Methods:Endometrial cancer cells ECC-1 were cultured and transfected with the miR-2... Objective:To study whether miR-200a and miR-200b target PTEN gene expression to regulate the endometrial cancer cell growth in vitro. Methods:Endometrial cancer cells ECC-1 were cultured and transfected with the miR-200a and miR-200b mimics and inhibitors as well as the negative control mimics and inhibitors,and then the cell proliferation activity as well as the expression of PTEN and downstream genes in cells was determined; after transfection of miR-200a and miR-200b mimics as well as PTEN-3’UTR luciferase report gene plasmids,the fluorescence activity of luciferase reporter gene was determined. Results:12 h,24 h and 48 h after transfection,the cell proliferation activity of miR-200a mimics group and miR-200b mimics group were significantly higher than those of NC mimics group while the cell proliferation activity of mi R-200 a inhibitor group and miR-200b inhibitor group were significantly lower than those of NC inhibitor group; 48 h after transfection,PTEN expression in cells and PTEN-3’UTR luciferase reporter gene fluorescence activity of miR-200 a mimics group and miR-200b mimics group were significantly lower than those of NC mimics group while p-PI3K and p-Akt expression were significantly higher than those of NC mimics group; PTEN expression in cells and PTEN-3’UTR luciferase reporter gene fluorescence activity of miR-200 inhibitor group and miR-200b inhibitor group were significantly higher than those of NC inhibitor group while p-PI3K and p-Akt expression were significantly lower than those of NC inhibitor group. Conclusion:miR-200 a and miR-200b can promote the endometrial cancer cell growth in vitro by targeted inhibition of PTEN gene expression. 展开更多
Banking deregulation and corporate tax avoidance
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作者 Bill B.Francis Ning Ren Qiang Wu 《中国会计学刊:英文版》 2017年第2期87-104,共18页
We investigate whether tax avoidance substitutes for external financing. We exploit interstate banking deregulation as a quasi-external shock to examine whether firms engage in less tax avoidance after banking deregul... We investigate whether tax avoidance substitutes for external financing. We exploit interstate banking deregulation as a quasi-external shock to examine whether firms engage in less tax avoidance after banking deregulation, because of cheaper and easier access to credit from banks. We find no empirical evidence to support this substitutive relation, even for firms with higher financial constraints or firms with higher external financing dependence. 展开更多
Clinical study inpatient-reported outcomes after binocular implantation of aspheric intraocular lens of different negative spherical aberrations
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作者 Ze-Quan Xu Xu-Hua Song +2 位作者 Wen-Zhe Li Yan Dou Qiang Wu 《亚太热带医药杂志:英文版》 SCIE CAS 2017年第7期771-774,共4页
Objective: To compare patient-reported outcomes after implantation of the ZA9003 intraocular lens(IOLs), or the MCX11 ASP IOLs or the spherical IOLs(HQ-201HEP). Methods: Prospective nonrandomized controlled trial was ... Objective: To compare patient-reported outcomes after implantation of the ZA9003 intraocular lens(IOLs), or the MCX11 ASP IOLs or the spherical IOLs(HQ-201HEP). Methods: Prospective nonrandomized controlled trial was used. A total of 105 patients(210 eyes) were divided into three groups according to the type of IOLs: ZA9003(35 patients, 70 eyes), MCX11 ASP(35 patients, 70 eyes) or HQ-201HEP(35 patients, 70 eyes). The main outcome was scores of Catquest nine-item short-form questionnaire. Additional outcome was best corrected visual acuities, spherical aberration(SA) and total higher-order aberrations(HOAs). Results: The global score was significantly lower in the spherical IOL group than the aspherical IOL group of-020 μm SA(P < 0.05) and the aspherical IOL group of-027 μm SA(P < 0.05), and no significant difference was found in the global score between the aspherical IOL group of-020 μm SA than the aspherical IOL group of-027 μm SA(P > 0.05). Significant differences were also found in question 2, question 5, question 6 and question 8 between the spherical IOLs and the aspherical IOLs. Conclusion: Implantation of an aspherical IOL could improve vision-related quality of life compared with a spherical IOL. However, there were no statistically significant differences in vision-related quality of life between aspheric IOLs with different negative spherical aberrations. 展开更多
Low-grade slightly elevated and polypoid colorectal adenomas display differential β-catenin-TCF/LEF activity, c-Myc, and cyclin D1 expression
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作者 Tian-wen Yang Yun-han Gao +2 位作者 Sha-Ying Ma Qiang wu Zhong-fu Li 《世界胃肠病学杂志:英文版》 SCIE CAS 2017年第17期3066-3076,共11页
AIM To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.METHODS Colorectal tumors were collected from 24 patients with slightly elevate... AIM To comparatively investigate the cellular and molecular characteristics of low-grade slightly elevated adenomas and polypoid adenomas.METHODS Colorectal tumors were collected from 24 patients with slightly elevated adenomas and 23 patients with polypoid adenomas. five commonly mutated genes(APC, BRAf, KRAS, NRAS, and PIK3CA) were selected for mutational analysis. Paraffin-embedded tumor sections were used to calculate the apoptotic index(AI) and Ki-67 labeling index(KLI). Two pure colorectal epithelial cell lines were created by pooling the slightly elevated and polypoid tumors. western blots, luciferase assays for β-catenin-T-cell factor protein/β-cateninlymphoid enhancer factor(β-catenin-TCf/LEf)-driven transcriptional activity, and caspase activity assays were conducted on the two cell lines.RESULTS Slightly elevated lesions showed a significantly lower APC mutational frequency and a significantly higher KRAS mutational frequency(both P < 0.05). Slightly elevated lesions showed a significantly lower AI(P < 0.05). β-catenin and β-catenin-TCf/LEf-driven transcriptional activity was significantly upregulated in slightly elevated lesions(both P < 0.05). In slightly elevated lesions, c-Myc was significantly downregulated, while cyclin D1 was significantly upregulated(both P < 0.05). β-catenin-TCf/LEf-driven transcriptional activity was negatively correlated with c-Myc(ρ =-0.78). Slightly elevated lesions displayed significant Bcl-2 and Bcl-x L upregulation(both P < 0.05) along with significant decreases in caspase-9 and caspase-3 activity(both P < 0.05). c-Myc was negatively correlated with Bcl-2 and Bcl-x L(ρ =-0.74 and-0.78, respectively).CONCLUSION The lower apoptotic activity of low-grade slightly elevated adenomas can be partly attributed to upregulated β-catenin pathway activity and downregulated c-Myc expression. 展开更多
关键词 癌症 Colorectal 腺瘤 -CATENIN 非水虫息似
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射频消融治疗符合米兰标准的早期肝癌疗效分析 被引量:2
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作者 崔芒芒 朱晓琳 +7 位作者 张倜 武强 崔云龙 李慧锴 李强 房锋 张伟 宋天强 《中国肿瘤临床》 CSCD 北大核心 2017年第11期539-543,共5页
目的:探讨射频消融治疗符合米兰标准的早期肝癌的疗效及预后危险因素.方法:回顾性分析天津医科大学肿瘤医院72例行射频消融治疗的符合米兰标准的早期肝癌患者病例,评估其术后恢复情况,分析复发率、生存率及预后危险因素.结果:72例患... 目的:探讨射频消融治疗符合米兰标准的早期肝癌的疗效及预后危险因素.方法:回顾性分析天津医科大学肿瘤医院72例行射频消融治疗的符合米兰标准的早期肝癌患者病例,评估其术后恢复情况,分析复发率、生存率及预后危险因素.结果:72例患者术后并发症轻微且恢复迅速,术后1、2、3年累积复发率分别为12.50%、20.83%和33.33%;1、2、3年累积生存率分别为93.06%、87.50%、79.17%.多因素分析提示肿瘤大小与复发密切相关,肿瘤大小与术前白蛋白水平是影响总生存的独立危险因素.结论:射频消融术治疗符合米兰标准的早期肝癌,近远期效果良好.肿瘤大小是复发的独立危险因素,肿瘤大小与术前白蛋白水平是影响总生存的重要因素. 展开更多
关键词 射频消融 米兰标准 肝癌 预后 危险因素
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我国利率市场化影响商业银行利差的机理研究:竞争效应还是风险效应
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作者 巫强 顾以诺 黄艳秋 《南大商学评论》 CSSCI 2017年第2期19-34,共16页
我国渐进式利率市场化改革能否促进商业银行之间的竞争并减少其利差,这对于能否真正实现利率完全由市场供求决定极为重要。借鉴代理商模型(Model of Dealership),本文证明利率市场化会通过"竞争效应"和"风险效应"这两种渠道影响... 我国渐进式利率市场化改革能否促进商业银行之间的竞争并减少其利差,这对于能否真正实现利率完全由市场供求决定极为重要。借鉴代理商模型(Model of Dealership),本文证明利率市场化会通过"竞争效应"和"风险效应"这两种渠道影响商业银行利差,利率市场化对商业银行利差的整体影响取决于这两种效应的比较。本文还利用我国16家上市商业银行2010年第二季度至2015年第一季度的面板数据,估计两次重要利率市场化事件对商业银行利差的实际影响。结果发现,总体上我国利率市场化进程导致商业银行利差缩小,竞争效应超过风险效应,该结论对中小型商业银行也成立;但由于其优势市场地位,我国国有大型商业银行利差并未受到利率市场化的显著影响。 展开更多
关键词 利率市场化 利差 商业银行
Optic
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作者 Yu-Lin Tao Li-Ming Tao +6 位作者 Zheng-Xuan Jiang He-Ting Liu Kun Liang Mo-Han Li Xuan-Sheng Zhu Yan-Lin Ren Bing-Jie Cui 《国际眼科杂志:英文版》 SCIE CAS 2017年第12期1883-1888,共6页
AIM: To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System(OQAS).METHODS: Seventy-four eyes wi... AIM: To evaluate the impact of spherical and aspherical intraocular lenses on the postoperative visual quality of age-related cataract patients using Optical Quality Analysis System(OQAS).METHODS: Seventy-four eyes with age-related cataracts were randomly divided into spherical and aspherical lens implantation groups. Best-corrected visual acuity(BCVA) was measured preoperatively, one day, one week, two weeks, one month and two months after surgery. A biometric systems analysis using the OQAS objective scattering index(OSI) was performed. RESULTS: There were no significant differences in visual acuity(P>0.05) before and after spherical and aspheric lens implantation. There was a negative linear correction between the OSI value and BCVA(r=-0.634, P=0.000), and positive corrections between the OSI value and the lens LOCUS III value of nucleus color(NC), nucleus opacity(NO), cortex(C) and posterior lens capsular(P)(r=0.704, P=0.000; r=0.514, P=0.000; r=0.276, P=0.020; r=0.417, P=0.000, respectively). OSI values of spherical vs aspherical lenses were 11.5±3.6 vs 11.8±3.4, 4.1±0.9 vs 3.3±0.8, 3.5±0.9 vs 2.7±0.7, 3.3±0.8 vs 2.6±0.7, 3.2±0.7 vs 2.5±0.8, and 3.2±0.8 vs 2.5±0.8 before and 1d, 1, 2wk, 1 and 2mo after surgery, respectively. All time points varied significantly(P<0.01) between the two groups.CONCLUSION: Aspherical IOLs does not significantly affect visual acuity compared with spherical IOLs. The OSI value, was significantly lower in the aspherical lens group compared with the spherical lens. This study shows that objective visual quality of aspheric IOLs is better than that of the spherical lens by means of OQAS biological measurement method. 展开更多
关键词 NERVE
Effect of hypoxia on expression of placental trophoblast cells SATB1 and β-catenin and its correlation with the pathogenesis of preeclampsia
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作者 Qiang Wu Gang Wu Jing-Xiang Li 《亚太热带医药杂志:英文版》 SCIE CAS 2016年第6期548-552,共5页
Objective: To study the effect of hypoxia on the expression of placental trophoblast cells SATB1 and β-catenin and its correlation with the pathogenesis of preeclampsia. Methods: Trophoblastic cell lines HRT8/SVneo w... Objective: To study the effect of hypoxia on the expression of placental trophoblast cells SATB1 and β-catenin and its correlation with the pathogenesis of preeclampsia. Methods: Trophoblastic cell lines HRT8/SVneo were cultured, SATB1 and β-catenin expression and cell biological behavior were determined after hypoxia reoxygenation treatment; cell biological behavior and the expression of related genes were determined after the transfection of SATB1 and β-catenin siR NA; preeclampsia placenta and normal placenta tissues were collected and the expression of SATB1 and β-catenin were determined. Results: OD value, cell migration rate, m RNA contents of SATB1 and β-catenin of H/R group were significantly lower than those of Nor group, cell apoptosis rate was higher than that of Nor group and the number of invasive cells was less than that of Nor group; OD value and bcl-2 mRNA content of SATB1-siRNA group were lower than those of NC group; cell apoptosis rate as well as Bax, Caspase-3, caspase-6 and caspase-9 mRNA contents were higher than those of NC group; cell migration rate as well as CTSB, CTSD, MMP2 and MMP9 mRNA contents of β-catenin-siRNA group were lower than those of NC group; the number of invasive cells was less than that of NC group; the expression levels of SATB1 and β-catenin in preeclampsia placenta tissue were significantly lower than those in normal placenta tissue. Conclusions: Hypoxia can inhibit the expression of SATB1 and β-catenin in the pathogenesis of preeclampsia, which can affect the proliferation, apoptosis, migration and invasion of cells. 展开更多
关键词 PREECLAMPSIA PLACENTAL TROPHOBLAST SATB1 BETA-CATENIN
CRISPR Double Cutting through the Labyrinthine Architecture of 3D Genomes
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作者 Haiyan Huang Qiang Wu 《遗传学报:英文版》 SCIE CAS CSCD 2016年第5期273-288,共16页
染色体被组织成订并且在分裂期间原子核的层次拓扑的结构。在每个染色体的分离领土以内,拓扑地联系了域(男孩) 在象基因规定那样的各种各样的原子进程起重要作用。在相对组成的边界分开的男孩内,远侧的元素通过象长途的提高倡导者相... 染色体被组织成订并且在分裂期间原子核的层次拓扑的结构。在每个染色体的分离领土以内,拓扑地联系了域(男孩) 在象基因规定那样的各种各样的原子进程起重要作用。在相对组成的边界分开的男孩内,远侧的元素通过象长途的提高倡导者相互作用那样的特定的循环染色质的接触调整他们的基因目标。高产量的定序研究揭示了百万个潜在的规章的 DNA 元素,它比更丰富仅仅 20,000 基因他们控制。编辑技术的最近出现的 CRISPR-Cas9 染色体启用了有效、精确基因并且染色体的 epigenetic 操作。多路、高产量的 CRISPR 能力便于基因的发现和解剖规章的元素。这里,我们为编辑的染色体, epigenome,和 3D 染色体描述 CRISPR 的应用,集中于与调查染色质男孩和发展基因规定的拓扑的合拢的 Cas9 和一双 sgRNAs 编辑的 CRISPR DNA 碎片。 展开更多
关键词 基因组 三维 DNA片段 建筑 迷宫 拓扑结构 编辑技术 基因调控
PCI techniques to aid implantation of CRT-D in a senior patient with persistent left superior vena cava 预览
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作者 Qiang WU Sha YU +1 位作者 Ya-Ping AN Bao-Lin CHEN 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2016年第7期639-642,共4页
关键词 心脏的再同步治疗 心失败 培植 Left  优异静脉 cava
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阿托伐他汀联合通心络及脑超声波干预易损斑块治疗缺血性脑血管病用药量分析
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作者 王焕君 李严 +3 位作者 吴强 徐成龙 田蕊 李雪艳 《现代电生理学杂志》 2016年第2期77-80,86共5页
目的:探讨阿托伐他汀联合通心络及脑超声波干预易损斑块治疗缺血性脑血管病用药剂量。方法:选择缺血性脑血管病患者183例,采用随机数字表法将其分为3组,治疗A组62例,口服通心络4粒,每日3次,阿托伐他汀10 mg,每日1次,同时常规给予脑超... 目的:探讨阿托伐他汀联合通心络及脑超声波干预易损斑块治疗缺血性脑血管病用药剂量。方法:选择缺血性脑血管病患者183例,采用随机数字表法将其分为3组,治疗A组62例,口服通心络4粒,每日3次,阿托伐他汀10 mg,每日1次,同时常规给予脑超声波SUT-800型,超声输出频率800 k HZ,声强0.75~1.25 w/cm2治疗每日一次,每次30min,10 d一个疗程,间隔1周再进行第二个疗程,6个月观察疗效;治疗B组60例,口服通心络4粒,每日3次,阿托伐他汀20 mg,每日1次,另加脑超声波治疗同治疗A组,6个月后观察疗效;对照组61例:仅给予口服普通降脂药心脑清及脑超声波治疗。观察3组患者治疗前后血脂变化及脂肪斑块情况。结果:与治疗前比较,治疗A组和B组,血清TC、TG、LDL-C浓度下降,HDL-C浓度升高,颈动脉IMT明显变小或消失,易损斑块减少,稳定斑块明显增加,斑块长径及厚度积分明显变小(P〈0.05),对照组治疗前后血脂水平及板块性质、数目差异无统计学意义;治疗后,与对照组比较,治疗A组和B组血脂水平下降,斑块长泾及厚度积分变小(P〈0.05);与治疗A组比较,B组血脂水平及斑块情况差异无统计学意义。结论:阿托伐他汀联合通心络、脑超声波治疗能明显降低血脂水平,干预颈动脉脂肪斑块疗效明显,而且可以减少阿托伐他汀的用药剂量。 展开更多
关键词 通心络 阿托伐他汀 脑超声波 缺血性脑血管病
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分级结构氮掺杂碳纳米笼担载的铂基高效甲醇氧化电催化剂 预览 被引量:1
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作者 蒋湘芬 王学斌 +5 位作者 沈丽明 吴强 王秧年 马延文 王喜章 胡征 《催化学报》 SCIE EI CAS CSCD 北大核心 2016年第7期1149-1155,共7页
高性能低成本的担载型铂基催化剂是直接甲醇燃料电池(DMFC)实用化过程中的一大挑战.利用高比表面积、高稳定性、容易负载金属的载体实现Pt颗粒的高度分散,既可提高催化剂的催化性能,又可提高Pt的利用率以降低成本,是担载型Pt基催化剂... 高性能低成本的担载型铂基催化剂是直接甲醇燃料电池(DMFC)实用化过程中的一大挑战.利用高比表面积、高稳定性、容易负载金属的载体实现Pt颗粒的高度分散,既可提高催化剂的催化性能,又可提高Pt的利用率以降低成本,是担载型Pt基催化剂实用化的有效途径.碳材料是一种常用的催化剂载体,近年来我们课题组发展了一种高性能的碳纳米笼材料,并可通过异原子掺杂调变其表面性能,提高其活性和负载能力.我们采用原位氧化镁模板法制备氮掺杂碳纳米笼:以具有多级结构的碱式碳酸镁作为氧化镁模板的前体,吡啶为碳源和氮源,经高温热解沉积,在原位形成的氧化镁模板表面形成氮掺杂的石墨化碳纳米薄层;经稀盐酸浸泡并洗涤,获得高纯度的氮掺杂碳纳米笼.氮掺杂碳纳米笼具有分等级的微纳米结构、高导电性、高比表面积和可调变的孔结构,结合表面氮原子的锚钉作用,氮掺杂碳纳米笼有望成为电化学催化剂Pt的优良载体.在前期研究基础上,本文探索多级结构氮掺杂碳纳米笼(hNCNC)作为新型载体负载Pt的能力,并评价所构建的负载型催化剂Pt/hNCNC的电催化性能.通过简便的微波辅助多元醇还原法,将氯铂酸还原成Pt纳米粒子负载于hNCNC的表面.为了揭示氮掺杂的效应,我们对比研究了具有相似分级结构但无掺杂的碳纳米笼(hCNC)以及商业化活性炭(Valcan XC-72)作为载体的情况.经热重(TG)和X射线光电子能谱(XPS)分析,三种催化剂Pt/hNCNC、Pt/h CNC和Pt/XC-72的负载量均接近理论负载量(23.1 wt%),都主要以金属态存在.然而,扫描电子显微镜(SEM)和透射电子显微镜(TEM)结果表明,Pt/hNCNC的Pt分散状态优于Pt/h CNC,更远优于Pt/XC-72.Pt/hNCNC的平均Pt粒径最小,仅约3.3 nm.这种良好的分散状态主要得益于氮原子掺杂,高负电性的氮原子改变了局域的表面极性,有利于Pt� 展开更多
关键词 甲醇氧化 燃料电池 铂催化剂 分级结构氮掺杂碳纳米笼 高性能
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广西东兰乌鸡的遗传多样性分析 预览 被引量:2
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作者 廖玉英 莫国东 +2 位作者 黄英飞 吴强 韦凤英 《农业科学与技术:英文版》 CAS 2016年第1期136-140,共5页
[目的]了解广西东兰乌鸡的遗传多样性及保种效果,为下一步的种质资源保护和育种研究提供参考依据。[方法]采集片羽东兰乌鸡和丝羽东兰乌鸡的翅静脉血样,提取总DNA,PCR扩增18个微卫星位点并对其基因片段进行扫描,利用Pop Gen 32生物软件... [目的]了解广西东兰乌鸡的遗传多样性及保种效果,为下一步的种质资源保护和育种研究提供参考依据。[方法]采集片羽东兰乌鸡和丝羽东兰乌鸡的翅静脉血样,提取总DNA,PCR扩增18个微卫星位点并对其基因片段进行扫描,利用Pop Gen 32生物软件分析测定东兰乌鸡群体的等位基因数(Na)、有效等位基因数(Ne)、杂合度(H)、多态信息含量(PIC),并与其他广西地方品种鸡进行聚类分析。[结果]18个微卫星标记在广西东兰乌鸡群中均表现出较高的多态性,从所检测的80个东兰乌鸡样本中共检测出98个等位基因,每个位点的平均Na为5.44个,Ne为2.78个,PIC为0.5382,H为0.5963。其中,丝羽东兰乌鸡和片羽东兰乌鸡分别检测到93和98个等位基因,平均每个位点的Ne分别为2.62和2.76个,PIC为0.508 8和0.539 8,H为0.624 7和0.599 1。聚类分析结果显示,东兰乌鸡与广西三黄鸡、霞烟鸡、南丹瑶鸡的遗传距离(DA)均较远,与其品种的进化、地理分布和选育历史基本相符。[结论]广西东兰乌鸡保种群的遗传变异较大,具有丰富的遗传多样性,其选育潜力较高。 展开更多
关键词 东兰乌鸡 微卫星标记 等位基因 遗传多样性 聚类分析
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相平衡主导的气-液-固生长机理:进一步的证据(英文)
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作者 张永亮 蔡婧 +4 位作者 吴强 王喜章 杨立军 何承雨 胡征 《中国科学:材料科学(英文版)》 CSCD 2016年第1期20-27,共8页
纳米材料的预测和设计是纳米科学与技术领域的长期梦想,该梦想的实现有赖于对生长机理的深刻理解.本文基于我们前期研究揭示的相平衡主导的气-液-固(VLS)生长机理,成功地预测了在1133~1638°C温区内通过氮化Al69Ni31合金颗粒生长Al ... 纳米材料的预测和设计是纳米科学与技术领域的长期梦想,该梦想的实现有赖于对生长机理的深刻理解.本文基于我们前期研究揭示的相平衡主导的气-液-固(VLS)生长机理,成功地预测了在1133~1638°C温区内通过氮化Al69Ni31合金颗粒生长Al N纳米线的过程,有关Al N纳米线的生长、共存Al-Ni合金相的晶格参数及形貌演变等预测均得到了定量化实验结果的证实,并界定了相平衡主导的VLS生长机理的适用条件.本文为相平衡主导的VLS生长机理的有效性提供了进一步的实验证据,同时展示了在生长机理的指导下根据相图设计和制备纳米材料的一个实例. 展开更多
关键词 NANOWIRES GROWTH prediction GROWTH mechanism phase EQUILIBRIUM QUANTITATIVE EXPERIMENTAL analysis
Novel Application of Vacuum Sealing Drainage with Continuous Irrigation of Potassium Permanganate for Managing Infective Wounds of Gas Gangrene 预览
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作者 Ning HU Xing-huo WU +7 位作者 Rong LIU Shu-hua YANG Wei HUANG Dian-ming JIANG Qiang wu Tian XIA Zeng-wu SHAO Zhe-wei YE 《华中科技大学学报:医学英德文版》 SCIE CAS 2015年第4期563-568,共6页
Traumatic gas gangrene is a fatal infection mainly caused by Clostridium perfringens. It is a challenge to manage gas gangrene in open wounds and control infection after debridement or amputation. The aim of the prese... Traumatic gas gangrene is a fatal infection mainly caused by Clostridium perfringens. It is a challenge to manage gas gangrene in open wounds and control infection after debridement or amputation. The aim of the present study was to use vacuum sealing drainage(VSD) with continuous irrigation of potassium permanganate to manage infective wounds of gas gangrene and observe its clinical efficacy. A total of 48 patients with open traumatic gas gangrene infection were included in this study. Amputations were done for 27 patients, and limb salvage procedures were performed for the others. After amputation or aggressive debridement, the VSD system, including polyvinyl alcohol(PVA) foam dressing and polyurethane(PU) film, with continuous irrigation of 1:5000 potassium permanganate solutions, was applied to the wounds. During the follow-up, all the patients healed without recurrence within 8–18 months. There were four complications. Cardiac arrest during amputation surgery occurred in one patient who suffered from severe septic shock. Emergent resuscitation was performed and the patient returned to stable condition. One patient suffered from mixed infection of Staphylococcal aureus, and a second-stage debridement was performed. One patient suffered from severe pain of the limb after the debridement. Exploratory operation was done and the possible reason was trauma of a local peripheral nerve. Three cases of crush syndrome had dialysis treatment for concomitant renal failure. In conclusion, VSD can convert open wound to closed wound, and evacuate necrotic tissues. Furthermore, potassium permanganate solutions help eliminate anaerobic microenvironment and achieve good therapeutic effect on gas gangrene and mixed infection. VSD with continuous irrigation of potassium permanganate is a novel, simple and feasible alternative for severe traumatic open wounds with gas gangrene infection. 展开更多
关键词 高锰酸钾溶液 伤口感染 灌溉管理 创面 应用 金黄色葡萄球菌 排水 密封
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Initial CT-guided Percutaneous Biopsy of Vertebral Lesions: Evaluation of Its Diagnostic Accuracy and Clinical Value 预览
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作者 Wen-bin HUA Qiang wu +5 位作者 Bo ZHANG Shu-hua YANG Zeng-wu SHAO Wei-hua XU Ye WANG Xu-dong ZHANG 《华中科技大学学报:医学英德文版》 SCIE CAS 2015年第4期569-573,共5页
This study aimed to examine the diagnostic accuracy and clinical efficacy of initial CT-guided percutaneous biopsy of the vertebral lesions. A total of 305 percutaneous biopsies of the vertebral lesions were performed... This study aimed to examine the diagnostic accuracy and clinical efficacy of initial CT-guided percutaneous biopsy of the vertebral lesions. A total of 305 percutaneous biopsies of the vertebral lesions were performed under either CT guidance(n=127) or C-arm guidance(n=178). The diagnostic accuracy rate was evaluated by comparing the histopathological diagnosis with the ultimate diagnosis. The histopathological diagnosis was consistent with the ultimate diagnosis in 108(85.0%, 108/127) cases of CT-guided biopsy and in 135(75.8%, 135/178) cases of C-arm guided biopsy and there was a significant difference. The accuracy of diagnosis based on biopsies varied with different diseases, including primary benign or malignant tumors, metastatic tumors, inflammatory lesions and fractures. A second biopsy or further examinations were required for patients with negative result obtained in the initial biopsy. The complication rate was 3.1%(4/127) in CT-guided biopsy and 7.3%(13/178) in C-arm guided biopsy. In conclusion, CT-guided percutaneous biopsy is an accurate and safe technique for biopsy of the vertebral lesions. 展开更多
关键词 诊断准确性 穿刺 活检 病变 临床价值 病理学诊断 恶性肿瘤 临床疗效
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Angle parameter changes of phacoemulsification and combined phacotrabeculectomy for acute primary angle closure
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作者 Shi-Wei Li Yan Chen +3 位作者 Qiang Wu Bin Lu Wen-Qing Wang Jian Fang 《国际眼科杂志:英文版》 SCIE CAS 2015年第4期742-747,共6页
·AIM: To evaluate the difference in angle parameters and clinical outcome following phacoemulsification and combined phacotrabeculectomy in patients with acute primary angle closure(APAC) using ultrasound biomicr... ·AIM: To evaluate the difference in angle parameters and clinical outcome following phacoemulsification and combined phacotrabeculectomy in patients with acute primary angle closure(APAC) using ultrasound biomicroscopy(UBM).·METHODS: Patients(n =23, 31 eyes) were randomized to receive phacoemulsification or combined phacotrabeculectomy(n =24, 31 eyes). Best-corrected visual acuity(BCVA), intraocular pressure(IOP), the main complications following surgery, and indentation gonioscopy and angle parameters measured using UBM were documented preoperatively and postoperatively.· RESULTS: The improvement in BCVA in the phacoemulsification group was significantly greater than in the combined group(P 【0.05). IOP in the phacoemulsification group was slightly higher than in the combined group following 1wk of follow-up(P 【0.05),whereas there was no significant difference between the two groups at the latter follow-up(P 】0.05).Phacoemulsification alone resulted in a slight increase in the trabecular ciliary processes distance compared with the combined surgery(P 【0.05), whereas the other angle parameters showed no significant difference between the groups. Complications in combined group were greater than phacoemulsification only group.·CONCLUSION: Both surgeries effectively opened the drainage angle and deepened the anterior chamber, and IOP was well controlled postoperatively. However,phacoemulsification showed better efficacy in improving visual function and showed reduced complications following surgery. 展开更多
关键词 ACUTE primary ANGLE CLOSURE CATARACT PHACOEMULSIFICATION PHACOTRABECULECTOMY
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