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81.
An 80-year-old man with multiple comorbidities presented to the emergency department with tachypnea, tachycardia, fever, and critically low O2 saturation and definitive chest computerized tomography scan findings in favor of COVID-19 and positive PCR results in 48 hours. He received antiviral treatment plus recombinant human erythropoietin (rhEPO) due to his severe anemia. After 7 days of treatment, he was discharged with miraculous improvement in his symptoms and hemoglobin level. We concluded that rhEPO could attenuate respiratory distress syndrome and confront the severe acute respiratory syndrome coronavirus 2 virus through multiple mechanisms including cytokine modulation, antiapoptotic effects, leukocyte release from bone marrow, and iron redistribution away from the intracellular virus.  相似文献   
82.
BACKGROUNDThere is recently a concern regarding the reinfection and reactivation of previously reCoVered coronavirus disease 2019 (CoVID-19) patients.AIMTo summarize the recent findings and reports of CoVID-19 reinfection in patients previously reCoVered from the disease.METHODSThis study was a systematic review of current evidence conducted in August 2020. The authors studied the probable reinfection risk of novel coronavirus (CoVID-19). We performed a systematic search using the keywords in online databases. The investigation adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of this study and results.RESULTSWe reviewed 31 studies. Eight studies described reCoVered patients with reinfection. Only one study reported reinfected patients who died. In 26 studies, there was no information about the status of the patients. Several studies indicated that reinfection is not probable and that post-infection immunity is at least temporary and short.CONCLUSIONBased on our review, we concluded that a positive polymerase chain reaction retest could be due to several reasons and should not always be considered as reinfection or reactivation of the disease. Most relevant studies in positive retest patients have shown relative and probably temporary immunity after the reCoVery of the disease.  相似文献   
83.
84.
Canine brucellosis, caused by Brucella canis, is an important cause of abortions, stillbirths, uveitis, epididymitis, orchitis, and sperm abnormalities in dogs. Anterior uveitis is one of the most common ocular diseases in dogs. The aim of this study was to describe the clinical and diagnostic features of anterior uveitis in dogs affected with B. canis in the Ahvaz district, southwestern Iran. A total of 243 blood samples were obtained from urban dogs between 2006 and 2010 and examined by immuno-chromatography assay (Anigen Rapid C. Brucella Ab Test Kit). Prevalence to B. canis antibodies was 6.58 % (16 out of 243) in the studied dogs. B. canis-induced anterior uveitis was seen in two German Shepherd dogs (12.5 %; 2 out of 16), the first was a 3.5-year-old male and the second was a 2.5-year-old female. Clinical ophthalmologic abnormalities included moderate anterior uveitis, mild conjunctival hyperemia, and iris hyperpigmentation. Following routine treatment (a median of 9 weeks from the onset of therapy), ocular inflammation resolved and serological tests were negative. The present study shows that ocular inflammation due to B. canis is present among the urban dog population in the Ahvaz district, Iran. B. canis infection should be included in the differential diagnosis for dogs with intraocular inflammation, regardless of previous history.  相似文献   
85.
Purified oleuropein from olive leaf extract indicated antioxidant properties in our previous reports. The recent study demonstrated that the lesions of absolute ethanol could be attributed to the increasing reactive oxygen species, subsequently lipid peroxidation and gastric ulcers. Therefore, the antioxidant effects of oleuropein as a natural antioxidant agent on intestine mucosal damages induced by absolute ethanol were investigated in the present study. The 42 adult male rats were divided into four (control, oleuropein, ethanol, and oleuropein plus ethanol) groups. Oleuropein at a dosage of 12 mg/kg was used for 10 consecutive days in oleuropein and oleuropein plus ethanol groups, thereafter absolute ethanol (once, 1 ml/rat) was administrated orally in ethanol and oleuropein plus ethanol groups at fasting state by gavage. The duodena of rats were removed for histopathology and antioxidant assay. Histological evidence of severe mucosal damages were confirmed by histopathology findings in ethanol group and prevented in oleuropein plus ethanol group. In this setting, glutathione peroxidase and catalase activities were significantly higher in oleuropein and oleuropein plus ethanol groups than the ethanol-treated rats. In contrast, thiobarbituric acid reactive substances concentration (as a lipid peroxidation marker) significantly increased in ethanol-treated rats when compared to the other groups. Our results suggest that olive leaf extract (containing oleuropein) exerts a potent antioxidant agent against oxidative stress. These findings allow us to exploit the advantages of oleuropein treatment in various diseases induced by oxidative stress in humans.  相似文献   
86.

Introduction

The aim of this in vivo study was to evaluate the influence of apical periodontitis (AP) on the accuracy of Dentaport ZX (J Morita, Kyoto, Japan), Raypex 5 (VDW, Munich, Germany), and i-Root (S-Denti, Seoul, Korea) electronic root canal length measurement devices (ERCLMDs).

Methods

Thirty-two single-rooted teeth scheduled for extraction, consisting of 16 teeth with AP and 16 teeth with normal periapex (NP), were selected. The access cavity was prepared, and the coronal portion of the canal was flared. The electronic working length (EWL) was determined by each ERCLMD according to each manufacturer's instructions. Each tooth was extracted, and the actual working length (AWL) was determined by inserting a size 15 K-file until the tip could be seen at a position tangential to the major foramen and then 0.5 mm was subtracted from the measurement. The distance from the file tip (EWL) to the point 0.5 mm coronal to the major foramen (AWL) was calculated. Data were analyzed using the nonparametric Fisher exact test and the chi-square test. Statistical significance was set at P < .05.

Results

The accuracies of Dentaport ZX, Raypex 5, and i-Root within ±0.5 mm in the AP group were 93.8%, 81.3%, and 75.0%; they were 93.3%, 86.7%, and 73.3% in the NP group, respectively. There were no significant differences between the accuracy of each device in the 2 groups (P > .05). Considering the 2 groups of AP and NP, there were no statistically significant differences in the accuracy of the ERCLMDs (P > .05).

Conclusions

The presence of AP did not influence the accuracy of ERCLMDs.  相似文献   
87.
BackgroundThe extremely high genetic heterogeneity of hearing loss due to diverse group of genes encoding proteins required for development, function, and maintenance of the complex auditory system makes the genetic diagnosis of this disease challenging. Up to now, 121 different genes have been identified for nonsyndromic hearing loss (NSHL), of which 76 genes are responsible for the most common forms of NSHL, autosomal recessive nonsyndromic hearing loss (ARNSHL).MethodsAfter excluding mutations in the most common ARNSHL gene, GJB2, by Sanger sequencing, genetic screening for a panel of genes responsible for hereditary hearing impairment performed in 9 individuals with ARNSHL from unrelated Iranian consanguineous pedigrees.ResultsOne compound heterozygote and eight homozygote variants, of which five are novel, were identified: CDH23:p.(Glu1970Lys), and p.(Ala1072Asp), GIPC3:p.(Asn82Ser), and (p.Thr41Lys), MYO7A:p.[Phe456Phe]; p.[Met708Val], and p.(Gly163Arg), TECTA:p.(Leu17Leufs*19), OTOF:c.1392+1G>A, and TRIOBP:p.(Arg1068*). Sanger sequencing confirmed the segregation of the variants with the disease in each family.ConclusionFinding more variants and expanding the spectrum of hearing impairment mutations can increase the diagnostic value of molecular testing in the screening of patients and can improve counseling to minimize the risk of having affected children for at risk couples.  相似文献   
88.
Production of activated nano-carbon from agricultural wastes was studied in this work. To obtain the optimum production conditions by a physical activation method, influence of temperature (850, 900, 950 and 1000 °C), activation residence time (30, 60 and 90 min), and mill rotation (200, 300 and 400 rpm) were investigated using three different raw materials including walnut, almond and pistachio shells. To prepare activated nano-carbon, all the samples were heated up to the final activation temperature under a continuous steam flow of 130 cm3 min−1, and at a heating rate of 3 °C min−1, and were held at the different activation temperatures for 30, 60 and 90 minutes. BET surface area of the obtained activated carbons was measured from nitrogen adsorption data in the relative pressure range between 0 to 1. Activated nano-carbon standard indexes were evaluated according to the ASTM standard and the samples were compared. First, the cellulose raw material was heated in the carbonization furnace at 600 °C and then activated in the advanced activation furnace at a temperature between 850 to 1000 °C for 30, 60 and 90 minutes with water vapor. Ash percentage, iodine content, moisture content, specific area, elemental analysis, and FESEM were used for product characterization. The results of the analysis showed that by using the water vapor physical activation method and optimizing the parameters of this process including time and rotation of the mill up to 10 min and 400 rpm, resulted in a significant increase in specific surface area, cavity volume and the iodine number of the final product.

Production of activated nano-carbon from agricultural wastes was studied in this work.  相似文献   
89.
90.
The fabricated NaY(WO4)2 was identified through diverse analysis methods. Therefore, to optimize NaY(WO4)2 morphology, saccharide carbohydrates were manipulated as a capping agent. In this study, glucose, fructose, lactose, cellulose, and starch were utilized as the capping agents. SEM images show that fructose was the optimal capping agent for achieving uniform and well-shaped nanoparticles. The photodegradation of organic dyes such as M.O and Rd.B by NaY(WO4)2 was evaluated under UV and Vis light. The bandgap energy of the as-prepared sample was measured by the Tauc plot, and was found to be nearly 3.85 eV. To study the photocatalytic characteristics, the influence of dye dosage and reusability on photodegradation behavior were investigated.

NaY(WO4)2 nanoparticles were fabricated via a simple hydrothermal method using saccharide carbohydrates as capping agents. The photocatalytic behavior of the as-prepared NaY(WO4)2 nanostructures was studied.  相似文献   
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