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61.
BONNIE J. BAKER M.D. † MICHAEL A. BRODSKY M.D. HA DINH M.D. † BYRON J. ALLEN M.D. BARBARA COTTER L.P.N. † CATHY LUCKETT R.N. MARVIN L. MURPHY M.D. † 《Journal of cardiovascular electrophysiology》1987,1(6):527-535
The effects of propafenone on left ventricular function and hemodynamics are presented in this study. In one group of 13 patients who underwent electrophysiological testing and subsequent chronic oral therapy with propafenone, eight had left ventricular ejection fractions determined by nuclear study before and during therapy with the drug. Initial measurements ranged from 22% to 39% (mean 30%), while those on chronic therapy showed no statistical difference and ranged from 22% to 48% (mean 30%). In a separate dose titration study of 14 patients, left ventricular ejection fraction showed a modest but significant decrease (52%± 9% to 48%± 11%; p < 0.05). This change was more marked in patients with an initial low ejection fraction. Propafenone appears to be safe in these patients but should be administered with caution in patients with particularly low ejection fractions. 相似文献
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Qandeel Rehman Aimal Daud Khan Adnan Daud Khan Muhammad Noman Haider Ali Abdul Rauf Muhammad Shakeel Ahmad 《RSC advances》2019,9(59):34207
Improving the photon absorption in thin-film solar cells with plasmonic nanoparticles is essential for the realization of extremely efficient cells with substantial cost reduction. Here, a comprehensive study of solar energy enhancement in a cadmium telluride (CdTe) thin-film solar cell based on the simple design of a square array of plasmonic titanium nanoparticles, has been reported. The excitation of localized plasmons in the metallic nanostructures together with the antireflection coating (ARC) significantly enhances the absorption of photons in the active CdTe layer. The proposed structure attained super absorption with a mean absorbance of more than 97.27% covering a wide range from visible to near-infrared (i.e., from 300 nm to 1200 nm), presenting a 90% absorption bandwidth over 900 nm, and the peak absorption is up to 99.9%. For qualitative analysis, the photocurrent density is also estimated for AM 1.5 solar illumination (global tilt), whose value reaches 40.36 mA cm−2, indicating the highest value reported to date. The impact of nanoparticle dimensions, various metal materials, shapes, and random arrangement of nanoparticles on optical absorption are discussed in detail. Moreover, the angle insensitivity is essentially validated by examining the absorption performance with oblique incidences and it is found that the solar cell keeps high absorption efficiency even when the incidence angle is greater than 0°. Therefore, these findings suggest that the proposed broadband structure has good prospect in attaining high power conversion efficiency while reducing the device cost.Improving the photon absorption in thin-film solar cells with plasmonic nanoparticles is essential for the realization of extremely efficient cells with substantial cost reduction. 相似文献
64.
Azizullah Azizullah Zia Ur Rehman Imran Ali Waheed Murad Noor Muhammad Waheed Ullah Donat-Peter Häder 《Parasitology research》2014,113(12):4321-4326
Dengue, a mosquito-borne viral infection, is one of the major public health concerns in the tropical and subtropical regions of the world. Approximately, 2.5 billion people across the world are at risk from dengue and 50 to 100 million new infections of dengue occur annually. There is yet no vaccine or medicine available against dengue, and treatment remains only supportive. Targeting its vector by a combination of biological and chemical approaches and management of breeding sites are currently the only existing approaches to control or eliminate dengue. Chlorophyll derivatives like chlorophyllin and pheophorbide have been reported as effective natural photosensitizers against larvae of several insects including flies. Chlorophyll derivatives were also reported effective against larval stages of freshwater snails as well as against certain parasites of fish. This article briefly discusses the possible application of chlorophyll derivatives in controlling dengue vectors and hence the disease itself. Chlorophyll derivatives can prove to be a good contributor in an integrated approach against dengue. 相似文献
65.
Arshad Mehmood Muhammad Ishaq Lei Zhao Bushra Safdar Ashfaq‐ur Rehman Masooma Munir Ali Raza Muhammad Nadeem Waheed Iqbal Chengtao Wang 《Chemical biology & drug design》2019,93(4):387-418
Hyperuricemia (HUA), a disease due to an elevation of body uric acid level and responsible for various diseases such as gout, cardiovascular disorders, and renal failure, is a major ground debate for the medical science these days. Considering the risk factors linked with allopathic drugs for the treatment of this disease, the debate has now become a special issue. Previously, we critically discussed the role of dietary polyphenols in the treatment of HUA. Besides dietary food plants, many researchers figure out the tremendous effects of medicinal plants‐derived phytochemicals against HUA. Keeping in mind all these aspects, we reviewed all possible managerial studies related to HUA through medicinal plants (isolated compounds). In the current review article, we comprehensively discussed various bioactive compounds, chemical structures, and structure–activity relationship with responsible key enzyme xanthine oxidase. 相似文献
66.
目的探讨血清前白蛋白(PALB)变化率与肝衰竭预后的关系。方法回顾性分析98例肝衰竭患者的临床资料,对患者进行Child-Pugh分级,并把患者分为好转组与未愈组,收集住院期间初始及末次PALB及其他主要肝功能指标的数值,并计算出PALB及其他主要肝功能指标的变化率。结果入院时患者的初始PALB数值明显下降,且Child-Pugh分级越高,数值越低。好转组与未愈组患者的初始PALB数值相近,当血清PALB数值快速升高时,好转组人数明显多于未愈组;当数值下降时,好转组人数明显少于未愈组;当数值升高不明显时,未愈组与好转组差异无统计学意义,但未愈组人数要多于好转组。PALB变化率的敏感度最高,特异度较总胆红素、凝血酶原活动度、国际标准化比值变化率低,而ROC曲线下面积最大。结论肝衰竭患者初始PALB明显比正常值低,而且病情越重,血清中PALB数值越低,但患者预后与初始PALB无相关性,而与PALB变化率相关。大部分PALB快速升高者,预后好;大部分PALB下降或升高缓慢者,预后差。而且PALB变化率对于预后的预测价值要高于其他主要肝功能指标。 相似文献
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68.
Afzal Hussain Perwez Alam Nasir Ali Siddiqui Mohamed Fahad Alajmi Md Tabish Rehman Mohd Abul Kalam Adnan Jathlan Al-Rehaily 《Saudi Pharmaceutical Journal》2018,26(7):970-976
Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6?×?100?mm, 3.5?µm) UPLC column. The optimized chromatographic condition was achieved at 0.16?mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235?nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt?=?2.723 and 3.068?min, respectively along with r2?>?0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis. 相似文献
69.
Fawad Ur Rehman Tianyu Du Sana Shaikh Xuerui Jiang Yun Chen Xiaoqi Li Huan Yi Jiang Hui Baoan Chen Matthias Selke Xuemei Wang 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(8):2619-2631
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al. 相似文献
70.
背景 透射电子显微镜(TEM)是检测病毒的重要手段,传统TEM检测常依靠专家手工观察,操作步骤繁琐,且已有机器学习方法易受到背景、噪声的影响,导致病毒检测方法准确率差、效率低且耗时长。 目的 探讨增强图卷积神经网络(EGCN)对TEM图像中的病毒形态自动识别问题,以提高TEM病毒检测的效率。 方法 EGCN模型利用卷积神经网络(CNN)提取像素间的局部特征信息,并结合样本特征之间的最近邻关系利用图卷积网络(GCN)进行图特征学习。在模型优化中联合优化群体超分类损失和分类交叉熵损失以提高EGCN模型对病毒类别信息特征的提取能力,较CNN对TEM病毒图像特征具备更强的特征提取能力。 结果 通过不同方法在15类TEM病毒图像数据集上开展实验,EGCN达到3.40%的top-1错误率、1.88%的top-2错误率、96.65%的精确度和96.60%的召回率,并通过一系列对比实验表明EGCN模型可以有效避免TEM图像中背景、噪声等的影响,提高对病毒识别的准确率。 结论 EGCN可以有效解决病毒形态识别任务,为病毒的诊断提供重要的参考价值。 相似文献