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排序方式: 共有8712条查询结果,搜索用时 78 毫秒
101.
Mahmut Akyol Muhammet Kazm Erol Ozdemir Ozdemir Deniz Turgut Coban Ahmet Burak Bilgin Esin Sogutlu Sari Elif Betul Turkoglu 《国际眼科》2015,8(1):23-28
AIM
To investigate the association of serum glucocorticoid kinase gene-1 (SGK-1) DNA variants with chronic central serous chorioretinopathy (CSC).METHODS
We enrolled 32 eyes of 32 patients who were diagnosed with chronic CSC and composed 32 normal eyes as a control group. Peripheral blood was used for DNA extraction and polymerase chain reaction (PCR) amplification. SGK1 gene was sequenced by using BigDye® Terminator v3.1 cycle sequencing KIT (Applied Biosystems, Foster City, CA, USA). The SGK1 gene and its variants were investigated in CSC patient group and control group.RESULTS
We identified a new polymorphism M32V in two person in the patient group (Minor allele frequency (MAF)=0.009) on the region of 1-60 amino acids. The rs1057293 was located in the encoder region of the SGK 1 gene but not associated with CSC (P=0.68). An intrinsic rs1743966 is also not associated (P=0.28).CONCLUSIONS
The new polymorphism M32V is located on the region of 1-60 amino acids which is necessary for localization to the mitochondria in CSC patient. This mutation is probably important for the energy metabolism and plays an important role in the cellular response to hyperosmotic stress and other stress stimuli. Both rs1057293 and rs1743966 are not associated with CSC. 相似文献102.
AIM:To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy (IVCM) in patients with keratoconus and control subjects.METHODS: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36 age-matched control subjects were evaluated with slit-lamp examination (SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte, endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated.RESULTS: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density (5817±306 cells/mm2 vs 4802±508 cells/mm2, P<0.001), anterior stromal keratocyte density (800±111 cells/mm2 vs 555±115 cells/mm2, P<0.001), posterior stromal keratocyte density (333±34 cells/mm2 vs 270±47 cells/mm2, P<0.001), endothelial cell density (2875±223 cells/mm2 vs 2686±265 cells/mm2, P<0.001), sub-basal nerve fiber density (31.2±8.4 nerves/mm2 vs 18.1±9.2 nerves/mm2, P<0.001), sub-basal nerve fiber length (21.4±3.4 mm/mm2 vs 16.1±5.1 mm/mm2, P<0.001), and sub-basal nerve branch density (median 50.0 (first quartile 31.2 - third quartile 68.7) nerve branches/mm2 vs median 25.0 (first quartile 6.2 - third quartile 45.3) nerve branches/mm2, P<0.001) were observed in patients with keratoconus.CONCLUSION: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus. 相似文献
103.
Cagla Celik Didar Tasdemir Ayse Demirbas Ahmet Kat O. Tolga Gul Behzat Cimen Ismail Ocsoy 《RSC advances》2018,8(45):25298
The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. The FNFs synthesized by an encouraging and novel approach not only showed high stabilities but also much enhanced catalytic activities as compared to free and conventionally immobilized enzymes. A recent development demonstrated that FNF formation has moved beyond the initial discovery in which enzymes and Cu2+ ions used as the organic and inorganic parts, respectively, are replaced with new organic (chitosan, amino acid and plant extracts) and inorganic (Cu2+ and Fe2+) materials. The new organic materials incorporated into FNFs act as Fenton-like agents and then show peroxidase-like activity owing to the metal ions and the porous structure of FNFs in the presence of hydrogen peroxide (H2O2). All FNFs have been widely utilized in many different scientific and industrial fields due to their greatly enhanced activities and stabilities. This review focuses primarily on the preparation, characterization, and bioanalytical applications of FNFs and explains the mechanisms of their formation and enhanced activities and stabilities.The discovery of functional organic–inorganic hybrid nanoflowers (FNFs) consisting of proteins/enzymes as the organic components and Cu(ii) ion as the inorganic component has made an enormous impact on enzyme immobilization studies. 相似文献
104.
Suna Sabuncuoglu Ayse Eken Ahmet Aydin Hilal Ozgunes Hilmi Orhan 《Drug and chemical toxicology》2015,38(4):375-382
We explored the association between the activities of antioxidant enzymes and their metallic cofactors in rats treated with cisplatin. The antioxidant effects of aminoguanidine, and a combination of vitamins E and C were investigated. Plasma platin was significantly lower than liver and kidney. Cisplatin treatment caused significant increase in plasma Se-glutathione peroxidase activity. Activities of Se-glutathione peroxidase, glutathione S-transferase, catalase and Cu,Zn-superoxide dismutase have been found to be significantly decreased in liver and kidney compared to controls. Zn levels in these organs were diminished upon cisplatin treatment, while levels of Cu were unaffected. Interestingly, levels of iron, the cofactor of catalase, were found to be significantly increased in liver and kidney. Intervention with aminoguanidine or vitamins was generally prevented cisplatin-caused changes in the activity of enzymes and in the tissue levels of cofactor metals. These observations suggest that relation between activities of enzymes and levels of cofactor metals is multifactorial. 相似文献
105.
Nedim Durmus Sefa Gültürk Tijen Kaya Tuncer Demir Mesut Parlak Ahmet Altun 《Indian journal of pharmacology》2015,47(1):34-38
Objectives:It is suggested that excessive calcium entry into neurons is the main triggering event in the initiation of epileptic discharges. We aimed to investigate the role of T and N type calcium channels in absence epilepsy experimental model.Results:Beta and delta recording ratios in 1 μM/5 μl mibefradil group was significantly different from basal and other dose-injected groups. Beta, alpha, and theta recordings in 0.2 μM/5 μl w-Conotoxin MVIIA group was significantly different from basal and other dose-injected groups. In w-Conotoxin MVIIA after mibefradil group, beta, alpha, and theta recording ratios were significantly different from basal and mibefradil group. Mibefradil and w-Conotoxin MVIIA significantly decreased the frequency and duration of SWDs. The decrease of frequency and duration of SWDs in mibefradil group was significantly different from w-Conotoxin MVIIA group. The frequency and duration of SWDs significantly decreased in w-Conotoxin MVIIA after mibefradil group compared with basal, mibefradil, and w-Conotoxin MVIIA groups.Conclusions:We concluded that both T and L type calcium channels play activator roles in SWDs and have positive effects on frequency and duration of these discharges. These results are related with their central effects more than peripheral effects.KEY WORDS: Epilepsy, mibefradil, T and N type calcium channels, Wistar Albino Glaxo/Rij rats, w-Conotoxin MVIIA 相似文献
106.
Sahin Serdar Gundogdu Aycan Nalbantoglu Ufuk Kadioglu Pinar Karaca Zuleyha Hacioglu Aysa Urhan Muhammed Emre Unluhizarci Kursad Demir Ahmet Numan Hora Mehmet Durcan Emre Elbüken Gülsah Dokmetas Hatice Sebile Zuhur Sayid Shafi Kelestimur Fahrettin 《Pituitary》2022,25(3):520-530
Pituitary - Our aim was to investigate the changes in the composition of oral and gut microbiota in patients with newly diagnosed acromegaly and their relationship with IGF-1 levels. Oral and fecal... 相似文献
107.
Sleep and Breathing - The aim was to determine sleep quality and related factors including restless leg syndrome in the 6th year medical students and medical residents in Pamukkale University,... 相似文献
108.
109.
Carbohydrate antigen 19-9 (CA19-9) has been used as a tumor marker in the diagnosis and differentiation of pancreatic cancers. However, significantly high levels of CA 19-9 in the absence of pancreatic malignancy have also been reported. We present a 50-year-old woman with a common bile duct stone and cholangitis, whose CA 19-9 level of 1.500 U/ml returned to normal after definitive treatment of choledocholithiasis. 相似文献
110.
Sari RA Kiziltunç A Taysi S Taysý S Akdemir S Akdemýr S Gündoğdu M 《Clinical rheumatology》2005,24(1):55-59
Behçets disease is a systemic vasculitis of unknown aetiology. Endothelial cell injury plays an important role in the pathogenesis and immunopathology of Behçets disease. E-selectin is expressed by activated endothelial cells. Because the selectin adhesion molecules are shed from activated cells, soluble forms of these proteins can be used as activation markers of endothelium (E-selectin). The pathogenesis of Behçets disease (BD) is closely related to endothelial cells, leucocyte functions and immunity. The aim of this study was to investigate circulating E-selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interaction of the leucocytes with endothelium in BD. Plasma E-selectin concentrations were evaluated in 23 patients with BD and 20 healthy control subjects. The disease activity was evaluated by clinical manifestations (oral aphthous ulcer, genital ulceration, positive pathergy test, skin lesions, eye involvement, thrombophlebitis and arthritis) and by laboratory investigations [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)]. The patients were newly or previously diagnosed cases not taking any drug for BD. Levels of E-selectin were measured with commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits using human sE-selectin (cat. no: BMS 205). Plasma E-selectin concentrations of patients and controls were compared with the Mann-Whitney U test. Statistical significance was assigned to p values lower than 0.05. Serum levels (mean±SD) of soluble E-selectin (sE-selectin) were significantly higher in 23 patients with BD than in 20 healthy controls (53.2±18.2 ng/ml vs 33.8±7.5 ng/ml, p<0.0001). A statistically significant positive correlation was observed between sE-selectin levels and CRP and ESR in patients with BD (r=0.78, p<0.001 and r=0.56, p<0.01, respectively). Increases in the E-selectin in BD may be a direct consequence of the leucocyte and endothelium activations observed during the disease process. The noninvasive investigations can be used as biochemical markers for inflammation. This may provide additional information regarding disease activity along with the traditional indices such as ESR and CRP. 相似文献