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51.
Interleukin 8 (IL-8), is a proinflammatory chemokine, has been reported to have angiogenic activity and to be responsible for tumor-associated angiogenesis in several cancers. In this study, we aimed to study the (IL-8) gene polymorphism in relation with risk development of non small cell lung cancer in Tunisian patient. Two single nucleotide polymorphisms (−251T/A [rs4073], +781C/T [rs2227306]) of the IL-8 gene were screened in 170 patients with NSCLC and 225 healthy controls by PCR–RFLP.  相似文献   
52.
This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs). The samples were successfully synthesized by the sol–gel method followed by annealing of the as-synthesized at 600, 800, 900, 1050, and 1200 °C. This approach yielded the formation of a highly crystalline structure with crystallite size ranging from 17 nm to 40 nm. X-ray diffraction (XRD), scanning electron microscopy (SEM) techniques, as well as energy disperse spectroscopy (EDS), Fourier transform infrared (FTIR) and Raman spectroscopy, were used in order to determine the structural and morphological properties of the prepared samples. Rietveld XRD refinement reveals that Ni–Zn–Al ferrite nanoparticles crystallize in inverse cubic (Fd3̄m) spinel structure. Using FTIR spectra, the elastic and thermodynamic properties were estimated. It was observed that the particle size had a pronounced effect on elastic and thermodynamic properties. Magnetic measurements were performed up to 700 K. The prepared ferrite samples present the highest Curie temperature, which decreases with increasing particle size and which is consistent with finite-size scaling. The thickness of the surface shell of about 1 nm was estimated from size-dependent magnetization measurements using the core–shell model. Besides, spin resonance, magnetostriction, temperature coefficient of resistance (TCR), and electrical resistivity properties have been scientifically studied and appear to be different according to their size. The optical properties of synthesized NZFAO nanoparticles were investigated, and the differences caused by the particle sizes are discussed on the basis of the phonon confinement effect. This effect was also inspected by the Raman analysis. Tuning of the physical properties suggests that the Ni–Zn–Al ferrite samples may be promising for multifunctional diverse applications.

This article presents the annealing effect on the structural, elastic, thermodynamic, optical, magnetic, and electric properties of Ni0.6Zn0.4Fe1.5Al0.5O4 (NZFAO) nanoparticles (NPs).  相似文献   
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55.
Pulmonary involvement in Beh?et's disease is an uncommon condition (12%). Thromboembolism of the superior vena cava and/or other mediastinal veins, aneurysms of the aorta and pulmonary arteries are the main vascular manifestations in addition to pulmonary infarct and intrathoracic hemorrhage. Despite their scarcity, respiratory symptoms may be life-threatening. The aim of this study was to assess the contribution of thoracic imaging for one of the most serious aspects of the disease: pulmonary artery aneurysm. We report five patients with pulmonary artery aneurysms (mean age: 39.5 years). Hemoptysia revealed Beh?et's disease in three. Initially explored by conventional radiography, computed tomography and angiography, pulmonary artery aneurysms are currently investigated well with helicoidal computed tomography, digital angiography, magnetic resonance imaging (MRI) and angio-MRI. These imaging techniques provide helpful information for the diagnosis of Beh?et's disease.  相似文献   
56.
A series of 1,2,4‐triazolo[1,5‐a]pyrimidine derivatives was designed, synthesized, and screened for their phosphodiesterase (PDE 4B) inhibitory activity and bronchodilation ability. Compound 7e showed 41.80% PDE 4B inhibition at 10 µM. Eight compounds were screened for their bronchodilator activity, where compounds 7f and 7e elicited promising bronchodilator activity with EC50 values of 18.6 and 57.1 µM, respectively, compared to theophylline (EC50 = 425 µM). Molecular docking at the PDE 4B active site revealed a binding mode and docking scores comparable to those of a reference ligand, consistent with their PDE 4B inhibition activity.  相似文献   
57.
To investigate the role of high-frequency ultrasonography in the diagnosis of calcium pyrophosphate dihydrate (CPPD) calcifications, in the most commonly affected joints in CPPD disease. Sixty patients with knee effusion were included in the study. All patients underwent musculoskeletal ultrasonography (on the shoulder, elbow, wrist, and knee joints), radiological examination of the sites examined by US, and synovial fluid analysis (using polarized light microscopy). Out of 60 patients with knee effusion, ultrasonographic calcifications (knees, shoulders, and wrists) were present in 38 patients (63.3%) and out of those patients; 32 had calcification characteristic of CPPD crystals deposition (hyperechoic deposits) in the knee and wrist joints. Pattern II (punctate pattern) was the most common pattern of calcification. It was present in all patients who had wrist calcification (18 patients) and in the knee in either alone (21 patients) or in association with pattern I (hyperechoic band) and/or pattern III (hyperechoic nodular or oval deposits) (9 patients). The sensitivity of ultrasonography for the detection of calcification was 84.2% while that of plain radiography was 13.2%, the specificity of both ultrasonography and plain radiography for the detection of calcification was 100%, and ultrasonography is valuable for diagnosing articular chondrocalcinosis via the detection of calcifications within the joint cartilage and fibrocartilage. Both sensitivity and specificity are high for detecting CPPD deposits.  相似文献   
58.
We compared findings from intraoperative live/real time three-dimensional transesophageal echocardiography (3DTEE) and two-dimensional transesophageal echocardiography (2DTEE) with surgery in 67 patients having aortic aneurysm and/or aortic dissection. Of these, 20 patients had aortic aneurysm without dissection, 21 aortic aneurysm and dissection, and 26 aortic dissection without aneurysm. 3DTEE diagnosed the type and location of aneurysm correctly in all patients unlike 2DTEE, which missed an aneurysm in one case. There were four cases of aortic aneurysm rupture. Three of them were diagnosed by 3DTEE but only one by 2DTEE, and one missed by both techniques. The mouth of saccular aneurysm, site of aortic aneurysm rupture, and communication sites between perfusing and nonperfusing lumens of aortic dissection could be viewed en face only with 3DTEE, enabling comprehensive measurements of their area and dimensions as well as increasing the confidence level of their diagnosis. In all patients with aortic dissection, 3DTEE enabled a more confident diagnosis of dissection because the dissection flap when viewed en face presented as a sheet of tissue rather than a linear echo seen on 2DTEE which can be confused with an artifact. 2DTEE missed dissection in one patient. In six cases the dissection flap involved the right coronary artery orifice by 3DTEE and surgery. These were missed by 2DTEE. Aortic regurgitation severity was more comprehensively assessed by 3DTEE than 2DTEE. Aneurysm size by 3DTEE correlated well with 2DTEE and surgery/computed tomography scan. In conclusion, 3DTEE provides incremental information over 2DTEE in patients with aortic aneurysm and dissection.  相似文献   
59.

Background

To determine the incidence of electrographic seizures during continuous electroencephalography (cEEG) in the medical and surgical ICU.

Methods

We retrospectively reviewed the records of all adults who underwent cEEG in our medical and surgical ICU over a 4.5 year period. Patients with acute brain injury were excluded. Our primary outcome was cEEG documentation of an electrographic seizure, defined as a rhythmic discharge or spike and wave pattern demonstrating definite evolution and lasting at least 10 s. To assess inter-rater variability in cEEG interpretation, two electrophysiologists independently reviewed all available cEEGs of subjects with electrographic seizures documented on their clinical cEEG report and those of an equal number of randomly selected subjects from the remaining cohort.

Results

Kappa analysis showed a value of 0.88, indicating excellent inter-rater agreement. Electrographic seizures were identified in 12 of 105 patients (11 %, 95 % CI 5–18 %). This rate did not change after excluding patients with a history of seizure, remote brain injury, or seizure-like events before cEEG. In an ordinal logistic regression model controlling for age, sex, and SOFA score, electrographic seizures were associated with lower odds of good outcomes on the Glasgow Outcome Scale at discharge (OR 0.3, 95 % CI 0.1–0.8).

Conclusion

In a tertiary care medical and surgical ICU, electrographic seizures were seen on 11 % of cEEGs ordered for the evaluation of encephalopathy, and were associated with worse functional outcomes at discharge. Our findings confirm the results of a prior study suggesting a substantial burden of electrographic seizures in critically ill encephalopathic patients.  相似文献   
60.
Obesity is a public health problem characterized by increased accumulation of fat into adipose tissues leading to oxidative stress, dyslipidemia, and chronic inflammatory status. We used an experimental model of high-fat diet-induced obesity to analyze the link between dyslipidemia, oxidative stress, and fat accumulation into adipose tissue of rats, as well as the involvement of intracellular mediators such as transition metals on signal transduction. We also looked at the ability of a grape seed and skin extract (GSSE) from a Tunisian cultivar to prevent fat-induced disturbances. Data showed that a high-fat diet (HFD) provoked dyslipidemia into plasma which is linked to an oxidative stress, an accumulation of transition metals such as manganese, copper, and zinc and a depletion of iron. GSSE prevented dyslipidemia by modulating lipase activity, together with increased antioxidant capacity and depletion of transition metals as well as of free radicals such as O2 ? and OH. These data indicated that GSSE has important preventive effects on HFD-induced obesity and oxidative stress whose transduction seems to involve transition metals. GSSE should be used as a safe anti-obesity agent that could find potential applications in metabolic disorders involving transition metals dyshomeostasis.  相似文献   
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