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101.
Brain Imaging and Behavior - Cognitive impairment is now recognized in a subset of patients with amyotrophic lateral sclerosis (ALS). The objective of the study was to identify group differences...  相似文献   
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In this study, an electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles (SiNWs/PtNPs) on a screen-printed carbon electrode (SPCE) for the detection of Sus scrofa mitochondrial DNA (mtDNA) in food utilizing a new hybrid indicator, ferrocenylnaphthalene diimide (FND). The morphology and elemental composition of the SiNWs/PtNPs-modified SPCE was analyzed by field emission scanning electron microscopy (FESEM) combined with energy dispersive X-ray spectroscopy (EDX). Cyclic voltammetry (CV) was used to study the electrical contact between the PtNPs and the screen-printed working electrode through SiNWs, while electrochemical impedance spectroscopy (EIS) was used to measure the charge transfer resistance of the modified electrode. The results clearly showed that the SiNWs/PtNPs were successfully coated onto the electrode and the effective surface area for the SiNWs/PtNPs-modified SPCE was increased 16.8 times as compared with that of the bare SPCE. Differential pulse voltammetry used for the detection of porcine DNA with FND as an intercalator confirmed its specific binding to the double-stranded DNA (dsDNA) sequences. The developed biosensor showed a selective response towards complementary target DNA and was able to distinguish non-complementary and mismatched DNA oligonucleotides. The SiNWs/PtNPs-modified SPCE that was fortified with DNA hybridization demonstrated good linearity in the range of 3 × 10−9 M to 3 × 10−5 M (R2 = 0.96) with a detection limit of 2.4 × 10−9 M. A cross-reactivity study against various types of meat and processed food showed good reliability for porcine samples.

An electrochemical DNA biosensor was developed based on the fabrication of silicon nanowires/platinum nanoparticles on a screen-printed carbon electrode for the detection of Sus scrofa mitochondrial DNA in food.  相似文献   
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Clinical Oral Investigations - 3D cephalometric analysis performed on cone-beam or multi-slice computed tomography (CBCT, MSCT) has superior diagnostic value compared to 2D cephalometry based on...  相似文献   
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BackgroundThe coronavirus diseases of 2019 (COVID-19) pandemic was classified as one of the worst pandemics in the 21st century. Its rapid transmission, unpredicted mortality rate, and the uncertainty surrounding its transmission method have evoked additional fear and anxiety. Nonetheless, to the best of our knowledge, no prior study has explored PTSD prevalence three months after the start of the quarantine procedures in Saudi Arabia nor has examined PTSD prevalence by three different methods.ObjectiveThis observational cross-sectional study aimed to identify the prevalence, severity, and influencing factors of PTSD in different regions of Saudi Arabia three months after the onset of the quarantine procedures related to the COVID-19 pandemic.MethodsThrough the month of June 2020, 1374 people (49.05% men and 50.95% women) completed a 35-item, 10-minute online. The prevalence of PTSD was measured using PCL-S (specific for COVID-19) that assesses the 17 symptoms of PTSD. Resilience was measured using 2-items Arabic version of the Connor-Davidson Resilience Scale 2 (CD-RISC 2).ResultsWe calculated the prevalence by three methods, namely, PTSD cut-off score, criteria, and combined, and the prevalence was 22.63%, 24.8%, and 19.6%, respectively. Female participants showed higher prevalence than male. As well, participants who were either tested positive or suspected of having been infected with COVID-19 showed higher PTSD prevalence. Higher resilience was associated with lower PTSD prevalence.ConclusionsThis was the first study to report PTSD prevalence by three differential methods three months after the onset of the quarantine procedures related to the COVID-19 pandemic in Saudi Arabia. We observed a significant impact of the COVID-19 pandemic in the Saudi population; therefore, great attention should be performed in implementing new procedures that deal with the highlighted risk factors, especially in vulnerable groups, to overcome the psychological impact of the COVID-19 pandemic.  相似文献   
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In this study, we aimed to compare the effects of dexpanthenol and N-acetylcysteine on wound healing. The wound healing process is a multifaceted sequence of activities associated with tissue restoration process. A number of investigations and clinical studies have been performed to determine new approaches for the improvement of wound healing. A total of 30 rats were divided into 3 equal groups. A linear 2-cm incision was made in the rats'' skin. No treatment was administered in the first (control) group. Dexpanthenol cream was administered to the rats in the second group and 3% N-acetylcysteine cream was administered to the rats in the third group. The wound areas of all of the rats were measured on certain days. On the 21st day, all wounds were excised and histologically evaluated. The epithelialization and granulation rates between the groups were revealed to be similar in microscopic evaluations. Although the fibrosis was remarkable in the control group as compared with the other groups, it was similar in N-acetylcysteine and dexpanthenol groups. Angiogenesis rate was remarkable in the N-acetylcysteine group compared with the others. In multiple-comparison analysis, Dexpanthenol and N-acetylcysteine groups had similar results in terms of wound healing rates (P < 0.05), which were both higher than in the control group (P > 0.05). The efficacy of N-acetylcysteine in wound healing is comparable to dexpanthenol, and both substances can be used to improve wound healing.Key words: N-acetylcysteine, Dexpanthenol, Wound healingWound healing is a multifaceted sequence of activities associated with the tissue restoration process.1 This activity takes place in 4 main steps: inflammation, proliferation, matrix deposition, and remodeling.2,3 Moreover, there are many factors that might have harmful effects on the wound healing process. In this regard, there have been numerous analyses and clinical studies aiming to find new methods for the improvement of wound healing processes.4Dexpanthenol is the biologically-active alcohol of pantothenic acid, which leads to an elevation in the amount of coenzyme A in the cell. Dexpanthenol is extensively used in topical form, since it can easily penetrate the skin even at large local concentrations. When used in formulations, dexpanthenol is most effective for the stimulation of epithelialization, granulation, and the mitigation of itching.5N-acetylcysteine (NAC) is a prodrug that supplies bioavailable cysteine for glutathione replenishment and prevents oxidative damage as well as inflammation. It also leads to glutathione (GSH) formation in the body. Besides fostering angiogenesis, it is used to scavenge free radicals. NAC has a number of functions in the stages of repair process, including cell proliferation, migration, and scratch wound healing. Moreover, NAC has also been reported to promote wound healing in diabetic rats.6In this study, we aimed to compare the effects of dexpanthenol, a molecule that is widely used to improve wound healing, and NAC, a molecule that reduces oxidative stress and inflammation, on wound healing.  相似文献   
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Hydatid cyst disease, which is endemically observed and an important health problem in our country, involves the spleen at a frequency ranking third following the liver and the lungs. In this study, we aimed to evaluate the efficacy and results of management in splenic hydatid cysts. The demographic data, localization, diagnosis, treatment methods, and the length of postoperative hospital stay of patients with splenic hydatid cysts in a 12-year period were evaluated retrospectively. Seventeen cases were evaluated. Among these, 13 were females and four were males. Seven had solitary splenic involvement, eight had involvement of both the spleen and the liver, and two had multiple organ involvement. Ten had undergone splenectomy, one had undergone distal splenectomy, and the remaining cases had undergone different surgical procedures. The patients had received albendazole treatment in the pre- and postoperative period. One patient had died secondary to hypernatremia on the first postoperative day. The clinical picture in splenic hydatid cysts, which is seen rarely, is usually asymptomatic. The diagnosis is established by ultrasonography and abdominal CT. Although splenectomy is the standard mode of treatment, spleen-preserving methods may be used.  相似文献   
110.
Chronic renal failure (CRF) is associated with oxidative stress that promotes production of reactive oxygen species (ROS). Melatonin, the chief secretory product of the pineal gland, was recently found to be a potent free radical scavenger and antioxidant. The aim of this study was to examine the role of melatonin in protecting the aorta, heart, corpus cavernosum, lung, diaphragm, and kidney tissues against oxidative damage in a rat model of CRF, which was induced by five of six nephrectomy. Male Wistar albino rats were randomly assigned to either the CRF group or the sham-operated control group, which had received saline or melatonin (10 mg/kg, i.p.) for 4 wk. CRF was evaluated by serum blood urea nitrogen (BUN) level and creatinine measurements. Aorta and corporeal tissues were used for contractility studies, or stored along with heart, lung, diaphragm, and kidney tissues for the measurement of malondialdehyde (MDA, an index of lipid peroxidation), protein carbonylation (PC, an index for protein oxidation), and glutathione (GSH) levels (a key antioxidant). Plasma MDA, PC, and GSH levels and erythrocytic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in CRF. In the CRF group, the contraction and the relaxation of aorta and corpus cavernosum samples decreased significantly compared with controls (P < 0.05-0.001). Melatonin treatment of the CRF group restored these responses. In the CRF group, there were significant increases in tissue MDA and PC levels in all tissues with marked reductions in GSH levels compared with controls (P < 0.05-0.001). In the plasma, while MDA and PC levels increased, GSH, SOD, CAT, and GSH-Px activities were reduced. Melatonin treatment reversed these effects as well. In this study, the increase in MDA and PC levels and the concomitant decrease in GSH levels of tissues and plasma and also SOD, CAT, GSH-Px activities of plasma demonstrate the role of oxidative mechanisms in CRF-induced tissue damage, and melatonin, via its free radical scavenging and antioxidant properties, ameliorates oxidative organ injury. CRF-induced dysfunction of the aorta and corpus cavernosum of rats was reversed by melatonin treatment. Thus, supplementing CRF patients with adjuvant therapy of melatonin may have some benefit.  相似文献   
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