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51.
Prognostic value of positive T wave in lead aVR in patients with non‐ST segment myocardial infarction
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Ahmad Separham MD Bahram Sohrabi MD Arezou Tajlil MD Leili Pourafkari MD FACC Robabeh Sadeghi MD Samad Ghaffari MD Nader D. Nader MD PhD FACC FCCP 《Annals of noninvasive electrocardiology》2018,23(5)
Background
Lead aVR provides prognostic information in various settings in patients with ischemia. We aim to investigate the role of a positive T wave in lead aVR in non‐ST segment myocardial infarction (NSTEMI).Methods
In a prospective cohort study, we included 400 patients with NSTEMI. Presentation electrocardiogram (ECG) was investigated for presence of a positive T wave as well as ST segment elevation (STE) in aVR and study variables were compared. Predictors of primary outcome defined as hospital major adverse cardiovascular events (MACE) and secondary outcome, defined as three‐vessel coronary disease and/or left main coronary artery stenosis (3VD/LMCA) stenosis in angiography, were determined in multivariate logistic regression analysis.Results
Patients with a positive T wave in aVR were significantly older and were more likely to be female. Left ventricular ejection fraction was significantly lower in patients of positive T group. Positive T group was more likely to have 3VD/LMCA stenosis (58.3% vs. 19.8%, p < .001). The prevalence of a positive T wave in aVR was significantly higher in MACE group (54.9 % vs. 24.8%, p < .001). However, in multivariate analysis, it was not an independent predictor of MACE (OR: 1.083 95% CI: [0.496–2.365], p: .841). Though, it was independently associated with presence of 3VD/LMCA stenosis (OR: 3.747 95% CI: [2.058–6.822], p < .001).Conclusion
Though positive T wave in lead aVR was more common in patients with MACE; it was not an independent predictor. Additionally, a positive T wave in aVR was an independent predictor of 3VD/LMCA stenosis in NSTEMI.52.
Abdul Samad Mohammed Omar Saad Aljebreen Abbas Saeed Hakeem Tahar Laoui Faheemuddin Patel Mirza Murtuza Ali Baig 《Materials》2022,15(3)
Due to rapid technological advancements, the demand for lightweight materials with improved tribo-mechanical properties is continuously growing. The development of composite materials is one of the routes taken by researchers to meet these target properties. Aluminum (Al) is one of the most suitable materials used for developing composites for a wide range of applications because of its light weight, high conductivity, and high specific strength. In this study, aluminum hybrid nanocomposites with alumina (10 Vol% Al2O3) and varying loadings of graphene oxide (0.25, 0.5 and 1 wt% GO) were fabricated using the spark plasma sintering technique. The tribological properties of the developed hybrid composites were evaluated by conducting ball-on-disk wear tests at a normal load of 3N, with a sliding speed of 0.1 m/s, and for a sliding distance of 100 m. A 440C hardened stainless steel ball with a diameter of 6.3 mm and a hardness of 62 RC was used as a counterface. Scanning electron microscopy (SEM), elemental X-ray dispersive analysis (EDS), and optical profilometry were used to ascertain the involved wear mechanisms. The results revealed that Al-10 Vol%Vol% Al2O3-0.25 wt% GO hybrid nanocomposite showed an increase of 48% in the hardness, a reduction of 55% in the specific wear rate, and a reduction of 5% in COF compared with pure aluminum. 相似文献
53.
Evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors 总被引:6,自引:0,他引:6
NL Dock ; HV Lamberson Jr ; TA O''Brien ; DE Tribe ; SS Alexander ; BJ Poiesz 《Transfusion》1988,28(5):412-418
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted. 相似文献
54.
目的 探讨用改进的倒谱方法估计平均骨小梁间距(mean trabecular bone spacing,MTBS)的可行性.方法 提出了一种基于反向滤波器的改进的倒谱分析方法用于估计MTBS,并将该方法应用于仿真及离体牛胫骨松质骨中的实验信号.结果 改进的倒谱方法能有效减少超声换能器脉冲响应和组织散射特性对倒谱的干扰,而且实现简单,计算量小.结论 相比于传统的倒谱方法,改进的倒谱方法在估计MTBS时, 对弥散散射和噪声有更强的鲁棒性,因此估计MTBS的精度更高. 相似文献
55.
目的探讨α-珠蛋白生成障碍性贫血产前诊断在降低出生缺陷中的效果。方法选择2003年1月至2012年7月进行α-珠蛋白生成障碍性贫血产前诊断的妊娠1 037例,采用聚合酶链反应结合琼脂糖凝胶电泳和反向点杂交技术对脐带血和原位培养后的羊水或绒毛组织检测α珠蛋白基因,同时对合并β-珠蛋白生成障碍贫血者进行β-珠蛋白基因检测。结果 1 037例妊娠中α-珠蛋白生成障碍性贫血检出率为79.27%,其中血红蛋白H(Hb Bart′s)胎儿水肿综合征292例,HbH病45例;同时检出中间型、重型β-珠蛋白生成障碍贫血5例,β-珠蛋白生成障碍贫血杂合子28例,包括α复合β-珠蛋白生成障碍贫血26例,终止妊娠339例。结论α-珠蛋白生成障碍性贫血产前干预是防止该类患儿出生的有效措施,同时应加强复合型珠蛋白生成障碍贫血的干预。 相似文献
56.
目的分析自闭症儿童父母的心理状况,实施及时有效的健康教育。方法采用症状自评量表(SCL-90)、抑郁自评量表(SDS)、焦虑自评量表(SAS )对89例自闭症儿童父母进行测评。并对这些父母实施有效的健康教育,对健康教育前的测评结果分别同国内常模、健康教育后比较。结果在健康教育实施前,自闭症儿童父母SCL-90、SAS、SDS得分均高于全国常模,差异有统计学意义(P<0.01);健康教育前后得分比较差异有统计学意义(P<0.01)。结论自闭症儿童父母普遍存在心理问题,及时开展健康教育能改善其心理状况。 相似文献
57.
Most of the newly developed drugs fails to achieve sufficient bioavailability in to brain due to low water solubility and low permeability. Drug delivery systems are one method for achieving entry of molecules to their desired site of action within the body. Dendrimers are the customizable nanopolymers with uniform and well-defined particle size and shape. Dendrimers are of eminent interest for biomedical applications because of their ability to cross cell membranes. This potential pharmaceutical delivery system crosses the blood brain barrier (BBB) and other important target points. The high level of control over the dendritic architecture (size, branching density, surface functionality) make dendrimers ideal carriers in the field of brain drug delivery of anticancer, antiinflammatory, and antimicrobial agents. Examples of dendrimers such as poly(amidoamine) (PAMAM), poly(propylene imine) (PPI) and polyether-copolyester (PEPE), Glyco, PEGylated, peptide and pH dendrimers are of outmost significance. These dendrimers carry the drug molecules by physical interactions (encapsulation) or through chemical bonding (prodrug approach), while pH sensitive dendrimers are able to deliver drug molecules by alteration of ionic exchange in the brain microenvironment at the tumor site. Techniques employing dendrimers could be especially useful for drugs targeting to Alzheimer's and Prion's diseases. The present review should be of value to scientists who wish to work on the dendrimers for the delivery of molecules into the brain by systemic dosing. 相似文献
58.
寰椎椎弓根螺钉置钉技巧探讨 总被引:2,自引:0,他引:2
[目的]探讨寰椎椎弓根螺钉固定治疗寰枢椎不稳的置钉技巧。[方法]总结2000年10月~2008年9月应用寰椎椎弓根螺钉技术治疗寰枢椎不稳患者66例,置钉132枚。术中在直视下依据手感行寰椎椎弓根螺钉置钉,复位固定。[结果]本组66例132枚螺钉均成功置入,复位固定满意。术中未发现脊髓、神经根、椎动脉等损伤。术后患者症状及神经脊髓功能均有不同程度恢复。96枚螺钉术后行CT检查,其中91枚位置良好(94.89%)。全部病例内固定无松动、断裂,植骨均融合。[结论]术前影像学测量,术中显露寰椎后弓、直视下依据手感置钉、X线确定进钉方向,是安全置钉的技巧。 相似文献
59.
目的:性治疗法目前尚未普及,本研究旨在评价性治疗法联合西地那非治疗勃起功能障碍(ED)的疗效。方法:根据治疗方法的不同将在本院治疗随访过的3130例维吾尔族ED患者分成2组。对照组625例,单纯口服西地那非3个月;试验组2505例,采用性治疗法联合西地那非治疗3个月。采用国际勃起功能问卷表(IIEF-5)在各组治疗前、后进行疗效评估,并随访12个月。结果:对照组治疗前、后及在6个月、12个月随访的IIEF-5评分分别为12.80±3.76、18.10±2.61、17.35±2.73和16.64±2.63;试验组治疗前、后及在6个月、12个月随访的IIEF-5评分分别为12.73±3.52、19.06±4.07、19.86±2.42和20.47±2.38。两组治疗前后IIEF-5评分自身对比差异均有显著性(P<0.05)。组间比较,试验组较对照组6个月和12个月随访IIEF-5评分均有显著性差异(P<0.05)。结论:性治疗法联合西地那非治疗ED的效果优于单纯西地那非治疗,并在12个月的随访中稳定性良好。 相似文献
60.
Ryoichi KAMIDE Laurent MISERY Nuria PEREZ‐CULLELL Vincent SIBAUD Charles TAÏEB 《The Journal of dermatology》2013,40(3):177-181
Sensitive skin syndrome was first described in 1977; however, no robust study has been carried out to evaluate its prevalence in Japan. A national representative sample of the Japanese population over the age of 18 years was taken. Individuals were questioned by telephone and selected according to the quota method. When asked “Do you have a sensitive skin?”, 52.84% of men and 55.98% of women answered “rather sensitive” or “very sensitive”. There was no significant difference (P = 0.22) between the two sexes. The non‐response rate among respondents was zero, suggesting that the term “sensitive skin” held a meaning for the majority of the population. Concerning questions about the onset of a rash, tingling or irritation in the presence of various factors, such as emotional issues, cold, heat, sun, dry air, air‐conditioning, water, air pollution and temperature variations, respondents with rather sensitive or very sensitive skin responded “yes” more often than others: approximately three‐times more often for water (18.97%/6.15%), air pollution (39.29%/12.45%) and warm climatic conditions (29.74%/9.8%). To our knowledge, this epidemiological study is the first to focus on sensitive skin among Japanese people of this century. It is of particular interest for two reasons: (i) it was conducted on a representative sample of the Japanese population; and (ii) the methodology used was identical to that used for sensitive skin assessment studies conducted in Europe and the USA, making it possible to draw certain comparisons. 相似文献