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31.
A novel MnO2 nanoparticles/chitosan-modified pencil graphite electrode (MnO2 NPs/CS/PGE) was constructed using two different MnO2 polymorphs (γ-MnO2 and ε-MnO2 nanoparticles). X-ray single phases of these two polymorphs were obtained by the comproportionation reaction between MnCl2 and KMnO4 (molar ratio of 5 : 1). The temperature of this reaction is the key factor governing the formation of the two polymorphs. Their structures were confirmed by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) and energy dispersive X-ray (EDX) analysis. Scanning electron microscopy (SEM) was employed to investigate the morphological shape of MnO2 NPs and the surface of the bare and modified electrodes. Moreover, cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were used for surface analysis of the modified electrodes. Compared to bare PGE, MnO2 NPs/CS/PGE shows higher effective surface area and excellent electrocatalytic activity towards the oxidation of the standard K3[Fe(CN)6]. The influence of different suspending solvents on the electrocatalytic activity of MnO2 was studied in detail. It was found that tetrahydrofuran (THF) is the optimum suspending solvent regarding the peak current signal and electrode kinetics. The results reveal that the modified γ-MnO2/CS/PGE is the most sensitive one compared to the other modified electrodes under investigation. The modified γ-MnO2/CS/PGE was applied for selective and sensitive determination of FUR. Under the optimized experimental conditions, γ-MnO2/CS/PGE provides a linear response over the concentration range of 0.05 to 4.20 μmol L−1 FUR with a low limit of detection, which was found to be 4.44 nmol L−1 (1.47 ng mL−1) for the 1st peak and 3.88 nmol L−1 (1.28 ng mL−1) for the 2nd one. The fabricated sensor exhibits a good reproducibility and selectivity and was applied successfully for the determination of FUR in its dosage forms and in spiked urine samples with good accuracy and precision.A novel MnO2 nanoparticles/chitosan-modified pencil graphite electrode (MnO2 NPs/CS/PGE) was constructed using two different MnO2 polymorphs (γ-MnO2 and ε-MnO2 nanoparticles). 相似文献
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Demir Arzu Meltem Aydin Fatma Acar Banu Kurt Tuba Poyraz Aylar Kiremitci Saba Gülleroglu Basak Azili Müjdem Nur Bayrakci Umut Selda 《Clinical rheumatology》2021,40(9):3817-3825
Clinical Rheumatology - Autoimmune pancreatitis (AIP) type 1 is an IgG4-related disease (IgG4-RD), characterized by inflammatory pseudotumors and histologically by dense lymphoplasmacytic... 相似文献
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Erdal Simay Nalbantoğlu Banu Gür Mert Berke Yıldırım Murathan Kılıçarslan Alperen Kaymaz-Tahra Sema Alibaz-Öner Fatma Yay Meral Mumcu Gonca Direskeneli Haner 《Clinical rheumatology》2021,40(10):4109-4116
Clinical Rheumatology - The aim of this study was to evaluate the relationships among the disease activity, illness perception, daily life performance, anxiety and depression status as potential... 相似文献
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Oner Ozdemir 《Allergy and asthma proceedings》2006,27(5):431-434
A case of idiopathic chronic urticaria (CU) is described briefly. The clinical characteristics, pathogenesis, diagnosis, and management of this disease are discussed followed by clinical pearls and pitfalls for the practicing allergist as well as the immunologist. CU, defined as recurring attacks of hives lasting for >6 weeks, is a common disorder for which the cause is determined in <20% of patients. Although the pathogenesis of idiopathic CU is not certain, the immune dysregulation/disruption causing autoimmunity is blamed. The diagnosis is based principally on the patient's history. Autologous serum skin test possibly should be performed in older children as a screening test for idiopathic autoimmune CU. This test shows the availability of serum IgG autoantibodies directed against the alpha-chain of FcepsilonRI. However, basophil mediator release assay still is accepted as a gold standard. Treatment is aimed first at avoiding underlying causative factors. Medications varying from H1-antihistamines to plasmapheresis as well as immunosuppressive therapies should be considered depending on clinical improvement. Spontaneous resolution of the disease is probable also. 相似文献
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Yasar Kucukardali Oral Oncul Saban Cavuslu Mehmet Danaci Semra Calangu Hakan Erdem Ayse Willke Topcu Zuhal Adibelli Murat Akova Emel Azak Karaali Ahmet Melih Ozel Zahit Bolaman Bulent Caka Birsen Cetin Erkan Coban Oguz Karabay Cagla Karakoc Mehmet Akif Karan Selda Korkmaz Gulsen Ozkaya Sahin Alaaddin Pahsa Fatma Sirmatel Emrullah Solmazgul Namik Ozmen Ilyas Tokatli Cengiz Uzun Gulsen Yakupoglu Bulent Ahmet Besirbellioglu Hanefi Cem Gul 《International journal of infectious diseases》2008,12(1):71-79
OBJECTIVE: The purpose of this trial was to determine the spectrum of diseases with fever of unknown origin (FUO) in Turkey. METHODS: A prospective multicenter study of 154 patients with FUO in twelve Turkish tertiary-care hospitals was conducted. RESULTS: The mean age of the patients was 42+/-17 years (range 17-75). Fifty-three (34.4%) had infectious diseases (ID), 47 (30.5%) had non-infectious inflammatory diseases (NIID), 22 (14.3%) had malignant diseases (MD), and eight (5.2%) had miscellaneous diseases (Mi). In 24 (15.6%) of the cases, the reason for high fever could not be determined despite intensive efforts. The most common ID etiologies were tuberculosis (13.6%) and cytomegalovirus (CMV) infection (3.2%). Adult Still's disease was the most common NIID (13.6%) and hematological malignancy was the most common MD (7.8%). In patients with NIID, the mean duration of reaching a definite diagnosis (37+/-23 days) was significantly longer compared to the patients with ID (25+/-12 days) (p=0.007). In patients with MD, the mean duration of fever (51+/-35 days) was longer compared to patients with ID (37+/-38 days) (p=0.052). CONCLUSIONS: Although infection remains the most common cause of FUO, with the highest percentage for tuberculosis, non-infectious etiologies seem to have increased when compared with previous studies. 相似文献
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Despite treatment with antibiotics, patients with complicated parapneumonic effusion (PPE) and empyema have an increased morbidity and mortality due at least in part to inappropriate management of the pleural effusion. PPE should be considered in all patients with pneumonia as antibiotic therapy is being initiated. If the diaphragms cannot be seen throughout their length on the chest radiographs, a lateral decubitus radiograph, ultrasonography or computerized tomography scan should be obtained. If the effusion is more than 10 mm in thickness, a therapeutic thoracentesis should be performed. If the fluid cannot all be removed and the characteristics of the pleural fluid indicate a poor prognosis, a chest tube should be inserted. If the drainage is incomplete due to loculation of the PPE intrapleural fibrinolytics or thoracoscopy should be performed. If the lung does not reexpand completely with thoracoscopy, then decortication should be performed without delay. 相似文献
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Hamady Dieng Rahimah Binti Hassan Ahmad Abu Hassan Idris Abd Ghani Fatimah Bt Abang Tomomitsu Satho Fumio Miake Hamdan Ahmad Yuki Fukumitsu Nur Aida Hashim Wan Fatma Zuharah Nur Faeza Abu Kassim Abdul Hafiz Ab Majid Rekha Selvarajoo Cirilo Nolasco-Hipolito Olaide Olawunmi Ajibola Andrew Alek Tuen 《Acta tropica》2015
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions. 相似文献
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