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OBJECTIVES:Pleural effusion is a common diagnostic and clinical problem. The differential diagnosis of pleural effusion may be difficult and may require several procedures, including invasive ones. Certain studies have investigated biochemical parameters to facilitate the diagnosis of exudative pleural effusion; however, it remains a challenging problem in clinical practice. We aimed to investigate the potential role of the neutrophil-lymphocyte ratio, which can be easily obtained by determining the cell count of the pleural fluid, in the differential diagnosis of exudative pleural effusion.METHODS:Records from patients who underwent thoracentesis and pleural fluid analysis between May 1, 2013, and March 1, 2015, were obtained from the electronic database of our hospital. The patients who met the inclusion criteria were divided into five groups according to their diagnosis: malignant pleural effusion, para-malignant pleural effusion, para-pneumonic effusion, tuberculosis-related effusion or other. The neutrophil-lymphocyte ratio value was calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. The patient groups were compared according to the given parameter.RESULTS:A total of 465 patients who met the inclusion criteria among 1616 patients with exudative pleural effusion were included in the study. The mean neutrophil-lymphocyte ratio value was significantly lower in tuberculosis-related pleural effusion compared to malignant, para-pneumonic and para-malignant effusions (p=0.001, p=0.001, p=0.012, respectively). The areas under the curve for tuberculosis pleurisy compared to malignant, para-pneumonic and para-malignant effusions were 0.38, 0.36, and 0.37, respectively. Lower cut-off values had higher sensitivity but lower specificity for tuberculosis pleurisy, while higher cut-off values had higher specificity but lower sensitivity for this condition.CONCLUSION:The pleural fluid neutrophil-lymphocyte ratio, which is an inexpensive, reproducible, and easily calculated hematological parameter, may facilitate the differential diagnosis of pleural effusion.  相似文献   
23.
We investigated the cytoprotective effect of melatonin in epirubicin-induced cardiotoxicity using four experimental groups of male Wistar rats: untreated control rats, epirubicin-treated rats, epirubicin+melatonin-treated rats, and melatonin-treated rats. We examined the histopathological and biochemical effects of melatonin on the epirubicin-induced changes and measured the levels of the lipid peroxidation end-product (malondialdehyde, MDA), an indicator of nitric oxide (NO) synthesis (nitrite/nitrate production), and reduced glutathione (GSH) in the heart. We also studied the extracellular matrix components (fibronectin, laminin) in the heart. Vacuole formation, mitochondrial deformation and degeneration, and disordered myofibrillary structures were detected ultrastructurally in the epirubicin-treated group. The degeneration was reduced in the heart tissues of the epirubicin+melatonin group. Epirubicin increased the nitrite/nitrate production, but did not change the MDA and GSH levels significantly. Melatonin treatment lowered the nitrite/nitrate concentrations, while increasing the GSH levels, which exceeded the levels in epirubicin+melatonin-treated rats. We conclude that the epirubicin increased the nitrozative stress, not the oxidative stress, in heart tissue, and the cardioprotective effect of melatonin was partially attributed to the suppression of epirubicin-induced nitrozative stress. These results suggest that melatonin partially protects against epirubicin-induced cardiotoxicity.  相似文献   
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Indacaterol is a new inhaled ultra-long acting β2-agonist. It has been recently approved in the European Union for the treatment of chronic obstructive pulmonary disease. This paper reports, for the first time, a method for the determination and validation of Indacaterol (IND) using an internal standard in capsules. Capillary electrophoretic separation was performed on an uncoated fused-silica capillary (50 cm effective length, 75 μm i.d.) and background electrolyte composed of 20 mmol L?1 of sodium tetraborate buffer, 15% (v/v) methanol (pH = 10.0) with the application of 20 kV of potential; 10 s at 5 × 103 N m?2 (50 mbar) of injection time; and wavelength of 200 nm and 25 °C of temperature. The linearity was evaluated in the range of 4.90 × 10?6 mol L?1 (2.50 μg mL?1) and 3.94 × 10?5 mol L?1 (20.00 μg mL?1), with R = 0.9993 for inter-day. LOD and LOQ values were 2.18 × 10?8 mol L?1 (0.011 μg mL?1) and 7.25 × 10?8 mol L?1 (0.037 μg mL?1) for inter-day, respectively. The precision values were 0.50–1.06% for intra-day and 2.12% for inter-day as RSD%. The accuracy was tested by the standard addition method with the recovery values being between 98.79 and 99.09 as percentages with RSD% interval of 0.01–0.80. The developed method was validated according to ICH guidelines. Indacaterol was successfully determined in Arcapta® capsule dosage form by the validated CE method with a relative error of 0.28%. The result was within the requirements of the USP 34-NF29. Therefore, the validated method may be used for the determination of Indacaterol in its capsules in quality control laboratories.  相似文献   
25.
Pulmonary artery aneurysm (PAA) is a rare entity with fatal complications. Its silent course contributes to large aneurysms with compression symptoms. We present a 39-year-old female idiopathic pulmonary arterial hypertension patient with a giant PAA causing severe pulmonary regurgitation (PR) and symptomatic left main coronary artery compression (LMCA). Since she had a failed LMCA stenting attempt, she underwent surgery. A valve-sparing David-like pulmonary trunk reconstruction and coronary artery bypass were performed. This case illustrates that David-like reconstruction procedure can be applied to the PAA with severe PR.  相似文献   
26.
在大学教学和学习中,学习兴趣是引导学生追求知识的最关键非智力因素之一,兴趣在目前的教育教学中受到越来越多的重视。本文主要论述了兴趣在大学生学习生活中的作用、个人应如何对待自身的兴趣以及作为教育工作者该如何引导和培养学生的学习兴趣,从而改善学习效果。  相似文献   
27.
Okadaic acid and its analogues are potent phosphatase inhibitors that cause Diarrheic Shellfish Poisoning (DSP) through the ingestion of contaminated shellfish by humans. This group of toxins is transmitted worldwide but the number of poisoning incidents has declined over the last 20 years due to legislation and monitoring programs that were implemented for bivalves. In the summer of 2012 and 2013, we collected a total of 101 samples of 22 different species that were made up of benthic and subtidal organisms such echinoderms, crustaceans, bivalves and gastropods from Madeira, São Miguel Island (Azores archipelago) and the northwestern coast of Morocco. The samples were analyzed by UPLC-MS/MS. Our main objective was to detect new vectors for these biotoxins. We can report nine new vectors for these toxins in the North Atlantic: Astropecten aranciacus, Arbacia lixula, Echinaster sepositus, Holothuria sanctori, Ophidiaster ophidianus, Onchidella celtica, Aplysia depilans, Patella spp., and Stramonita haemostoma. Differences in toxin contents among the species were found. Even though low concentrations were detected, the levels of toxins that were present, especially in edible species, indicate the importance of these types of studies. Routine monitoring should be extended to comprise a wider number of vectors other than for bivalves of okadaic acid and its analogues.  相似文献   
28.
Dear Editor,
The cytosolic protein Tau is naturally present in human neurons, where it has a pivotal role in controlling microtubule stability. Hyperphosphorylation of Tau (observed during neurodegenerative diseases, such as Alzheimer's disease) impairs the protein's ability to bind microtubules. This results in microtubule disassembly and the formation of Tau aggregates, Tau protein is also widely expressed in peripheral tissues. In the male reproductive system, screening for Tau has focused solely on the rodent and bovine testis. In the present study, we used immunofluorescence and immunoenzymatic techniques (with a Tau-specific antibody) to investigate the presence of Tau protein in human ejaculated sperm and testicular tissue.  相似文献   
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We have previously demonstrated that the activation of the spleen tyrosine kinase (Syk)/inhibitory‐κB (IκB)‐α/nuclear factor‐κB (NF‐κB) p65 signalling pathway contributes to hypotension and inflammatory response in a rat models of zymosan (ZYM)‐induced non‐septic shock. The purpose of this study was to further examine the possible mechanism underlying the effect of inhibition of Syk by BAY61‐3606 via NF‐κB activity at the level of nuclear translocation regarding the production of vasodilator and proinflammatory mediators in lipopolysaccharide (LPS) (septic)‐ and ZYM (non‐septic)‐induced shock. Administration of LPS (10 mg/kg, ip) or ZYM (500 mg/kg, ip) to male Wistar rats decreased mean arterial pressure and increased heart rate that was associated with an increase in the activities of cyclooxygenase and nitric oxide synthase, tumour necrosis factor‐α, and interleukin‐8 levels, and NF‐κB activation and nuclear translocation in sera and/or cardiovascular and renal tissues. BAY61‐3606 (3 mg/kg, ip), the selective Syk inhibitor, given 1 hour after LPS‐ or ZYM injection reversed all the above‐mentioned effects. These results suggest that Syk contributes to the LPS‐ or ZYM‐induced hypotension and inflammation associated with transactivation of NF‐κB in septic and non‐septic shock.  相似文献   
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