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111.
Nur Indah Fajar Mukti Teguh Ariyanto Wahyudi Budi Sediawan Imam Prasetyo 《RSC advances》2021,11(58):36782
The separation of CO2/CH4 can be enhanced by impregnating porous carbon with iron oxide. Dispersion of iron oxide is one of the critical factors which supports the separation process performance. Iron oxide dispersion can be enhanced by enriching the oxygen functional groups on the carbon surface. This study investigates three distinct oxidation processes: oxidation with a 10% H2O2 solution, ozonation with distilled water, and ozonation with a 10% H2O2 solution. The research steps included the following: (i) oxidation, (ii) impregnation of iron oxide followed by calcination, (iii) material characterization, and (iv) material performance analysis. Materials were characterized using N2 sorption analysis, X-ray diffraction analysis (XRD), scanning electron microscopy-energy dispersive X-ray spectroscopy analysis (SEM-EDX), and Fourier transform infrared analysis (FT-IR). Iron oxide was well dispersed on the carbon surface, as evidenced by the elemental mapping of materials. In addition, the oxygen functional groups increased significantly in the range of 28.6–79.7% following the oxidation process, as indicated by the elemental component using SEM-EDX analysis. The impregnation of iron oxide on oxidized carbon ozonated with distilled water (COA–Fe) obtained a maximum CO2 uptake capacity of 3.0 mmol g−1 and CO2/CH4 selectivity increased by up to 190% at a temperature of 30 °C and pressure of 1 atm. Furthermore, the enhancement of CO2/CH4 separation up to 1.45 times was the best performance achieved by COA–Fe. Thus, improving iron oxide dispersion on oxidized carbon surfaces has a potential application in CO2/CH4 separation.The separation of CO2/CH4 can be enhanced by impregnating porous carbon with iron oxide. 相似文献
112.
血管紧张素原基因5′端核心启动子区(-6)A-G和(-20)A-C变异与哈萨克族人原发性高血压相关性分析 总被引:19,自引:0,他引:19
目的 研究血管紧张素源 (angiotensinogen,AGT)基因核心启动子区域 (- 6 ) A- G和 (- 2 0 )A- C位点变异与哈萨克族人原发性高血压相关关系。方法 采用经典的饱和酚 /氯仿抽提法提取哈萨克族正常人 74名和高血压患者 12 5例白细胞基因组 DNA,通过 PCR、单链构象多态性、限制性片段长度多态性和测序等技术 ,鉴定不同个体 AGT基因核心启动子区域 (- 6 )、(- 2 0 )位等位基因的类型 ,观察在高血压组和正常血压组不同基因型的分布和等位基因频率的差异。结果 (1)哈萨克族人 AGT基因 - 16 4~ 73区域仅存在 (- 6 ) A- G、(- 2 0 ) A- C两种变异。(2 ) AGT基因 (- 6 )位点 AA、AG、GG基因型的频率在高血压组和正常血压组分别为 0 .39、0 .4 5、0 .16和 0 .4 9、0 .4 9、0 .0 2 ,两组之间差异存在显著性 (χ2 =8.5 6 ,P=0 .0 14 )。A、G等位基因频率分别为 0 .6 2、0 .38和 0 .73、0 .2 7,差异存在显著性 (χ2 =5 .35 ,P=0 .0 2 1)。(3) AGT基因 (- 2 0 )位点 AA、AC、CC基因型频率在高血压组和正常血压组分别为 0 .6 9、0 .2 6、0 .0 5和 0 .6 5、0 .32、0 .0 3,差异无显著性 (χ2 =2 .4 2 ,P=0 .30 ) ;A、C等位基因的频率分别为 0 .82、0 .18和 0 .82、0 .18,差异无显著性 (χ2 =0 ,P=0 .99)。(4) AGT基 相似文献
113.
Berna Solak MD Bahar Sevimli Dikicier MD Nur C. Cosansu MD Teoman Erdem MD 《International journal of dermatology》2017,56(3):341-345
In patients with vitiligo, the clinical and laboratory features of the disease may vary according to time of onset. This is addressed in the literature by only a few studies with conflicting results. The aim of this study was to determine the demographic and clinical features of patients with non‐segmental vitiligo and to establish the association between vitiligo and autoimmune diseases with a focus on time of disease onset. A total of 224 vitiligo patients for whom complete medical records were available were evaluated retrospectively. Demographic data, scores on the Vitiligo Area Score Index (VASI), clinical features, vitiligo disease activity, repigmentation status, presence of any accompanying autoimmune disease, antinuclear antibody (ANA) titers, serum levels of glucose, thyroid‐stimulating hormone (TSH), thyroxine (T4) hormone, anti‐thyroid peroxidase (anti‐TPO), and anti‐thyroglobulin (anti‐TG) were recorded. The prevalence of halo nevi was significantly higher (P < 0.001) among children than in other patient groups. The prevalence of leukotrichia was higher in adults with adult‐onset disease than in either pediatric patients or adults with childhood‐onset disease (P = 0.002). Both anti‐TG and anti‐TPO levels were significantly higher in adults with adult‐onset disease than in pediatric patients and adult patients with childhood‐onset disease. The prevalence of autoimmune disease was 22.2%. Anti‐TG levels were significantly higher in patients with treatment‐related repigmentation than in those without repigmentation. This study shows that clinical features and associations with autoimmune disease may vary according to the age of onset of vitiligo. 相似文献
114.
Edith Wagner Anna Shin Nur Tukhanova Nurkeldi Turebekov Talgat Nurmakhanov Vitaliy Sutyagin Almas Berdibekov Nurbek Maikanov Ilmars Lezdinsh Zhanna Shapiyeva Alexander Shevtsov Klaus Freimüller Lukas Peintner Christina Ehrhardt Sandra Essbauer 《Viruses》2022,14(4)
Omsk haemorrhagic fever virus (OHFV) is the agent leading to Omsk haemorrhagic fever (OHF), a viral disease currently only known in Western Siberia in Russia. The symptoms include fever, headache, nausea, muscle pain, cough and haemorrhages. The transmission cycle of OHFV is complex. Tick bites or contact with infected small mammals are the main source of infection. The Republic of Kazakhstan is adjacent to the endemic areas of OHFV in Russia and febrile diseases with haemorrhages occur throughout the country—often with unclear aetiology. In this study, we examined human cerebrospinal fluid samples of patients with suspected meningitis or meningoencephalitis with unknown origins for the presence of OHFV RNA. Further, reservoir hosts such as rodents and ticks from four Kazakhstan regions were screened for OHFV RNA to clarify if this virus could be the causative agent for many undiagnosed cases of febrile diseases in humans in Kazakhstan. Out of 130 cerebrospinal fluid samples, two patients (1.53%) originating from Almaty city were positive for OHFV RNA. Screening of tick samples revealed positive pools from different areas in the Akmola region. Of the caught rodents, 1.1% out of 621 were positive for OHFV at four trapping areas from the West Kazakhstan region. In this paper, we present a broad investigation of the spread of OHFV in Kazakhstan in human cerebrospinal fluid samples, rodents and ticks. Our study shows for the first time that OHFV can not only be found in the area of Western Siberia in Russia, but can also be detected up to 1.600 km away in the Almaty region in patients and natural foci. 相似文献
115.
116.
Zunaina Embong Wan Hazabbah Wan Hitam Chan Yean Yean Nur Haslindawaty Abdul Rashid Balqis Kamarudin Siti Khaironi Zainal Abidin Sabariah Osman Zainul F Zainuddin Manickam Ravichandran 《BMC ophthalmology》2008,8(1):7
Background
The sensitivity and specificity of 18S rRNA polymerase chain reaction (PCR) in the detection of fungal aetiology of microbial keratitis was determined in thirty patients with clinical diagnosis of microbial keratitis. 相似文献117.
Yüksel N Karabaş L Altintaş O Yildirim Y Cağlar Y 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2002,216(1):45-49
PURPOSE: To compare the short-term ocular hypotensive efficacy and side effects of 0.2% brimonidine and 0.5% apraclonidine in patients with elevated intraocular pressure (IOP). METHODS: We performed a double-masked, placebo-controlled study to compare the efficacy of the application of 0.2% brimonidine and 0.5% apraclonidine for the effect of IOP, systemic blood pressure and heart rate in 20 newly diagnosed ocular hypertensive patients. Effects on the untreated fellow eye and ocular side effects were also determined. All measurements were performed 1, 2, 4, 6 and 8 h after the instillation of one drop. RESULTS: Brimonidine and apraclonidine significantly reduced IOP from baseline at all observation times. No significant difference was observed between the treatment groups. IOP decreased significantly in the untreated fellow eye in the brimonidine group at 4-, 6- and 8-hour checks and at 6-hour checks in the apraclonidine group when compared with placebo. Blood pressure and heart rate decreased significantly in the brimonidine group compared with placebo. Apraclonidine did not affect blood pressure or heart rate any differently than placebo. The pupil diameter and the interpalpebral fissure width significantly increased in the apraclonidine group, but not in the brimonidine group. There were no significant differences in the overall incidence of foreign body sensation, burning and stinging and dry mouth in the treatment groups. CONCLUSIONS: In the short-term, brimonidine was effective in reducing IOP in patients with elevated IOP and was equivalent in efficacy to apraclonidine. On the other hand, a significant change in blood pressure and heart rate was observed with brimonidine; there was no change at all in the apraclonidine group. 相似文献
118.
Bilateral elastofibroma dorsi 总被引:1,自引:0,他引:1
Elastofibroma dorsi was diagnosed in a 48-year-old woman with bilateral subscapular tumor masses diagnosed asynchronously in an interval of 4 months in spite of presence of another lesion at first admittance. She underwent subsequent resections of the lesions. They were diagnosed as elastofibroma. Reevaluation of the initial computerized tomography of thorax indicated an omitted small lesion with a 2-cm diameter and 25.2-day doubling time. Although the real neoplastic nature of elastofibroma is unknown, bilateral presence of the masses with different sizes and relatively short doubling times of the lesions must be kept in mind. 相似文献
119.
120.