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排序方式: 共有746条查询结果,搜索用时 15 毫秒
31.
M. Ikram R. Tabassum U. Qumar S. Ali A. Ul-Hamid A. Haider A. Raza M. Imran S. Ali 《RSC advances》2020,10(35):20559
Nanostructured materials incorporated with biological reducing agents have shown significant potential for use in bactericidal applications. Such materials have also demonstrated considerable efficacy to counter effects of chemical toxicity. In this study, nanostructured molybdenum disulfide (MoS2) was doped with various concentrations (2.5, 5, 7.5, 10 wt%) of zirconium (Zr) using a hydrothermal route in order to assess its antimicrobial and catalytic potential. Doped and control samples were characterized with various techniques. X-ray diffraction (XRD) analysis confirmed the presence of the hexagonal phase of MoS2 and identification of various functional groups and characteristic peaks (Mo bonding) was carried out using FTIR spectra. Micrographs obtained from FESEM and HR-TEM showed a sheet-like surface morphology, while agglomeration of nanosheets was observed upon doping with nanoparticles. To seek further clarity regarding the layered features of S–Mo–S planes, the defect densities and electronic band structure of pure MoS2 and doped MoS2 samples were investigated through Raman analysis. Optical properties of Zr-doped MoS2 nanosheets were assessed using a UV-vis spectrophotometer and the results indicated a red-shift, i.e., movement of peaks towards longer wavelengths, of the material. Dynamics of migration and recombination of excited electron–hole pairs were investigated using PL spectroscopy, which was also used to confirm the presence of exfoliated nanosheets. In addition, the synthetic dye degradation potential of pure and doped samples was investigated in the presence of a reducing agent (NaBH4). It was noted that doped MoS2 showed superior catalytic activity compared to undoped MoS2. The nanocatalyst synthesized in this study exhibited enhanced antibacterial activity against E. coli and S. aureus at high concentrations (0.5, 1.0 mg/50 μl). The present study suggests a cost-effective and environmentally friendly material that can be used to remove toxins such as synthetic dyes and tannery pollutants from industrial wastewater.Nanostructured materials incorporated with biological reducing agents have shown significant potential for use in bactericidal applications. 相似文献
32.
Heidi C. Saavedra Perez Nese Direk Albert Hofman Meike W. Vernooij Henning Tiemeier Mohammad Arfan Ikram 《Psychiatry Research: Neuroimaging》2013,211(2):180-182
The present study included 1047 elderly participants. At baseline, brain magnetic resonance imaging (MRI) was performed to detect infarcts and white matter lesions; further, depressive disorders were assessed. Participants were followed up during 3.6 years to determine incident and recurrent depression. We found an increased risk of recurrent depression associated with silent brain infarcts. 相似文献
33.
Xiao Tian Wijnant Sara Renata Alex van der Velpen Isabelle Terzikhan Natalie Lahousse Lies Ikram M. Kamran Vernooij Meike W. Brusselle Guy G. Ikram M. Arfan 《Journal of neurology》2022,269(8):4141-4153
Journal of Neurology - To investigate the association of chronic obstructive pulmonary disease (COPD) and Preserved Ratio Impaired Spirometry (PRISm) with cognitive performance and presence of... 相似文献
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Hemorheological aspects of the metabolic syndrome: markers of insulin resistance, obesity or hyperinsulinemia? 总被引:1,自引:0,他引:1
The metabolic syndrome is a major health problem in western countries, due to the deleterious metabolic consequences of sedentarity and rich diet in the large part of the population who exhibits the so-called "thrifty phenotype". This syndrome, which is at high risk for diabetes and atherothrombosis is associated with hemorheologic abnormalities. Initially, insulin resistance was considered as the core of the syndrome. However, it becomes clear that the syndrome is a cluster in which the combined effects of obesity, insulin resistance, and hyperinsulinemia can be inconstantly associated. Thus, we investigated in 157 nondiabetic subjects (53 males and 104 females, age 35.6+/-1.1 yr, mean BMI 29.2+/-0.6 kg/m2) the respective importance of each of these factors. Subjects were divided in 6 groups according to BMI (cut-off point 25 kg/m2) and insulin sensitivity (SI) measured with the minimal model (lowest quartile SI<1.1 min(-1)/(microU/ml) x 10(-4), highest quartile SI>9.5, middle zone between 1.1 and 9.5). Results show that whole blood viscosity at high shear rate is higher in obese subjects (p<0.01). Plasma viscosity is also higher in obese subjects 1.41+/-0.02 vs 1.34+/-0.012 (p<0.01), and, in addition, in lean subjects, is lower when SI is in the upper quartile. RBC rigidity index "Tk" is higher in obese subjects. A worsening effect of insulin resistance (SI<1.1) on Tk is found only in obese subjects. The aggregability index "M1" is increased when SI<1.1 in both obese and nonobese subjects. No clear effect of either SI or obesity on hematocrit is observed. On the whole, obesity and insulin resistance both impair blood rheology by acting on red cell rigidity and plasma viscosity. Whole blood viscosity at high shear rate reflects rather obesity than insulin resistance. Myrenne "M1" aggregation is rather a marker of hyperinsulinemia. Thus, the hemorheologic picture of the metabolic syndrome is far to be only a reflect of insulin resistance alone. 相似文献
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Walid Jomaa Ouday Benabdeljelil Ikram Chamtouri Wajih Abdallah Khaldoun Ben Hamda Faouzi Maatouk 《La Tunisie médicale》2021,99(7):744
Background. Coronary artery disease is the leading cause of death in emerging countries. Contemporary data about clinical profile and prognosis in Tunisian patients presenting for non ST-elevation acute coronary syndrome (NSTE-ACS) are lacking. Aim. We sought to study the risk profile and 3-year mortality predictors in Tunisian patients presenting for NSTE-ACS in the contemporary setting. Methods. In this single center study, data about all consecutive patients presenting to our center for NSTE-ACS from April 2014 to July 2016 were extracted and outcomes exhaustively updated. 3-year mortality predictors were determined by multivariable survival analysis. Results. A total of 340 patients were included, of which 204 (61.8%) were male. Mean age was 63.6 ± 10.3 years. Prevalence of diabetes mellitus, hypertension and smoking was 57.3%, 62.4%, and 45.3%, respectively. In-hospital, 6, 12 and 36-month mortality rate was 2.3%, 3.2%, 7.1% and 15.2%, respectively. In multivariable survival analysis, independent predictors of death were age >75 (HR=5.45, 95% CI: 2.9-10.03, p<0.001), ST-segment deviation (HR=1.86, 95% CI: 1.04-3.33, p=0.036), anemia (HR=2.56, 95% CI: 1.41-4.67, p=0.002), left ventricular ejection fraction (LVEF) <40% (HR=3.5, 95% CI: 1.84-6.67, p<0.001) and a Global Registry of Acute Coronary Events (GRACE) score ≥140 (HR=2.38, 95% CI: 1.02-5.57, p=0.044) Conclusion. In Tunisian patients presenting for NSTE-ACS, long-term mortality was high. Advanced age, ST-segment deviation, anemia, LVEF <40% and a GRACE score ≥140 were independent long-term predictors of death. 相似文献
39.
Anissa Chouikha Wasfi Fares Asma Laamari Sondes Haddad-Boubaker Zeineb Belaiba Kais Ghedira Wafa Kammoun Rebai Kaouther Ayouni Marwa Khedhiri Samar Ben Halima Henda Krichen Henda Touzi Imen Ben Dhifallah Fatma Z. Guerfali Chiraz Atri Saifeddine Azouz Oussema Khamessi Monia Ardhaoui Mouna Safer Nissaf Ben Alaya Ikram Guizani Rym Kefi Mariem Gdoura Henda Triki 《Viruses》2022,14(3)
Documenting the circulation dynamics of SARS-CoV-2 variants in different regions of the world is crucial for monitoring virus transmission worldwide and contributing to global efforts towards combating the pandemic. Tunisia has experienced several waves of COVID-19 with a significant number of infections and deaths. The present study provides genetic information on the different lineages of SARS-CoV-2 that circulated in Tunisia over 17 months. Lineages were assigned for 1359 samples using whole-genome sequencing, partial S gene sequencing and variant-specific real-time RT-PCR tests. Forty-eight different lineages of SARS-CoV-2 were identified, including variants of concern (VOCs), variants of interest (VOIs) and variants under monitoring (VUMs), particularly Alpha, Beta, Delta, A.27, Zeta and Eta. The first wave, limited to imported and import-related cases, was characterized by a small number of positive samples and lineages. During the second wave, a large number of lineages were detected; the third wave was marked by the predominance of the Alpha VOC, and the fourth wave was characterized by the predominance of the Delta VOC. This study adds new genomic data to the global context of COVID-19, particularly from the North African region, and highlights the importance of the timely molecular characterization of circulating strains. 相似文献
40.
Fauzia Rehman Ikram Ullah Khan Syed Haroon Khalid Sajid Asghar Muhammad Irfan Ikrima Khalid Akhtar Rasul Huma Mahmood Abid Mehmood Yousaf Yasser Shahzad Muhammad Mudassar Noor Ul Amin Mohsin 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2021,29(1):171
BackgroundIn recent era, pH sensitive polymeric carriers that combines the materials engineering and medicine is gaining researcher’s attention as they maximizes drug concentration at site of absorption and reduces side effects for e.g. orally administered cetirizine HCl (CTZ HCl) upsets the stomach and furthermore shows high intestinal absorption. Thus, development of pH sensitive hydrogels with sufficient mechanical strength will be good candidate to address this issue.MethodsHere, we developed pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum (IA-g-poly(AM)/sterculia gum) semi-interpenetrating network (semi-IPN) by free radical polymerization technique for intestinal delivery of CTZ HCL.ResultsOptimized formulation (I5) with 6% w/w IA showed negligible swelling at pH 1.2, and maximum swelling at pH 7.4. Solid state characterization of optimized formulation showed successful development of semi-IPN structure and incorporation of drug without any noticeable drug-carrier interaction. In vitro release study showed biphasic pH dependent release of CTZ HCl, where initial burst release was observed at acidic pH followed by sustained release at basic pH. Acute oral toxicity and histopathological studies confirmed the non-toxic nature of IA-g-poly(AM)/sterculia gum.ConclusionConclusively, developed biocompatible semi-IPN hydrogels with sufficient pH sensitivity and mechanical strength could serve as a potential carrier for intestinal delivery of CTZ HCL to maximize its absorption and reduce side effects.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s40199-021-00395-8. 相似文献