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排序方式: 共有4713条查询结果,搜索用时 15 毫秒
41.
Aleksandr Kolchin Dmitrii Shuleiko Mikhail Martyshov Aleksandra Efimova Leonid Golovan Denis Presnov Tatiana Kunkel Victoriia Glukhenkaya Petr Lazarenko Pavel Kashkarov Stanislav Zabotnov Sergey Kozyukhin 《Materials》2022,15(10)
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density. 相似文献
42.
Sandra Lepak-Kuc Katarzyna Wasilewska Daniel Janczak Tatiana Nowicka Magorzata Jakubowska 《Materials》2022,15(10)
In this study, the extremely important and difficult topic of flexographic printing on a heat-shrinkable substrate was taken up. Six commercially available, electrically conductive inks based on silver, copper and graphite nanoparticles were selected and tested upon their applicability for printing on the temperature-sensitive PET material. As a printing substrate, the one-direction heat-shrinkable PET film, with a maximum shrinkage of 78%, was selected. All of the examined inks were subjected to the printing process throughout three different anilox line screens. The tested inks, along with the electric paths printed with them, were subjected to various tests. The main parameters were evaluated, such as printability combined with the rheology tests and ink adhesion to the examined PET substrate together with the electrical conductivity before and after the shrinkage. 相似文献
43.
Daria Matyushkina Varvara Shokina Polina Tikhonova Valentin Manuvera Dmitry Shirokov Daria Kharlampieva Vasily Lazarev Anna Varizhuk Tatiana Vedekhina Alexander Pavlenko Leonid Penkin Georgij Arapidi Konstantin Pavlov Dmitry Pushkar Konstantin Kolontarev Alexander Rumyantsev Sergey Rumyantsev Lyubov Rychkova Vadim Govorun 《Viruses》2022,14(6)
COVID-19 caused by SARS-CoV-2 is continuing to spread around the world and drastically affect our daily life. New strains appear, and the severity of the course of the disease itself seems to be decreasing, but even people who have been ill on an outpatient basis suffer post-COVID consequences. Partly, it is associated with the autoimmune reactions, so debates about the development of new vaccines and the need for vaccination/revaccination continue. In this study we performed an analysis of the antibody response of patients with COVID-19 to linear and conformational epitopes of viral proteins using ELISA, chip array and western blot with analysis of correlations between antibody titer, disease severity, and complications. We have shown that the presence of IgG antibodies to the nucleoprotein can deteriorate the course of the disease, induce multiple direct COVID-19 symptoms, and contribute to long-term post-covid symptoms. We analyzed the cross reactivity of antibodies to SARS-CoV-2 with own human proteins and showed that antibodies to the nucleocapsid protein can bind to human proteins. In accordance with the possibility of HLA presentation, the main possible targets of the autoantibodies were identified. People with HLA alleles A01:01; A26:01; B39:01; B15:01 are most susceptible to the development of autoimmune processes after COVID-19. 相似文献
44.
Alexandre de Matos Soeiro Bruno Biselli Tatiana C.A.T. Leal Aline Siqueira Bossa Maria Cristina Csar Srgio Jallad Priscila Gherardi Goldstein Patrícia Oliveira Guimares Carlos Vicente Serrano Jr Cesar Higa Nomura Dbora Nakamura Carlos Eduardo Rochitte Paulo Rogrio Soares Múcio Tavares de Oliveira Jr. 《Arquivos brasileiros de cardiologia》2022,118(5):894
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events. 相似文献
45.
Robert M. Levy Alexander Khokhlov Sergey Kopenkin Boris Bart Tatiana Ermolova Raiasa Kantemirova Vadim Mazurov Marjorie Bell Paul Caldron Lakshmi Pillai Bruce P. Burnett 《Advances in therapy》2010,27(10):731-742
Introduction
Flavocoxid is a novel flavonoid-based “dual inhibitor” of the 5-lipoxygenase (5-LOX) enzyme and the cyclooxygenase (COX) enzymes. This study was designed to compare the effectiveness and safety of flavocoxid to naproxen in subjects with moderate to severe osteoarthritis (OA) of the knee.Methods
In this randomized, multicenter, double-blind study, 220 subjects were assigned to receive either flavocoxid (500 mg twice daily) or naproxen (500 mg twice daily) for 12 weeks. The trial was structured to show noninferiority of flavocoxid to naproxen. Primary outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and subscales and a timed walk.Results
More than 90% of the subjects in both groups noted significant reduction in the signs and symptoms of knee OA. There were no statistically significant differences in efficacy between the flavocoxid and naproxen groups when the entire intent-to-treat population was analyzed. The flavocoxid group had significantly fewer upper gastrointestinal (UGI) and renal (edema) adverse events (AEs) as well as a strong trend toward fewer respiratory AEs.Conclusion
Flavocoxid, a first-in-class flavonoid-based therapeutic that inhibits COX-1 and COX-2 as well as 5-LOX, was as effective as naproxen in managing the signs and symptoms of OA of the knee. Flavocoxid demonstrated better UGI, renal (edema), and respiratory safety profiles than naproxen. 相似文献46.
In a previous study we showed that prediction tools are useful to select single-nucleotide polymorphisms (SNPs) which potentially affect phenotype and therefore guide genotyping in association studies, thus saving time and money. Here we use the recently available RNA cross-link immunoprecipitation data to analyze several genes involved in psychiatric disorders and show which disease-associated SNPs can affect the splicing process by altering splicing factor binding sites. We point out the importance of using cross-link immunoprecipitation data in psychiatry to refine the SNP selection methods, to explain the association found and to plan molecular investigations. 相似文献
47.
Tatiana M. Sakamoto Andreia A. Canalli Fabiola Traina Carla F. Franco-Penteado Sheley Gambero Sara T.O. Saad Nicola Conran Fernando F. Costa 《Clinical biochemistry》2013
Objectives
Intravascular hemolysis may have important pathophysiological consequences, such as the induction of cellular adhesion and vasculopathy. We compared the adhesive properties of red cells (RBC) and platelets in hereditary spherocytosis (HS), paroxysmal nocturnal hemoglobinuria (PNH) and sickle cell disease (SCD) patients.Design and methods
The adhesion of RBC and platelets, from patients and healthy subjects, was determined using static adhesion assays. RBC surface markers were characterized by flow cytometry and lactate dehydrogenase (LDH), plasma hemoglobin (pHb) and TNF-α were assayed in serum/plasma samples.Results
pHb levels were elevated in all three hemolytic diseases, indicating the incidence of intravascular hemolysis. RBC adhesion and TNF-α were augmented in HS and SCD, but not in PNH. Reticulocyte counts were raised in the three diseases, but were higher in HS and SCD than in PNH; high expressions of CD71, CD36 and CD49d were observed on SCD RBC, while CD71 alone was increased on HS and PNH RBC. Splenectomy was associated with reversals of increased pHb, RBC adhesion, reticulocytes, RBC marker expression and inflammation in HS. In contrast, platelet adhesion was elevated in SCD and PNH, but not HS. Platelet adhesion correlated significantly with serum LDH, but not pHb, in the hemolytic disease cohort; interestingly, LDH did not correlate with reticulocytes or pHb levels.Conclusions
Results indicate that extravascular, rather than intravascular, hemolysis (and ensuing RBC production) may contribute to elevations in RBC adhesive properties in HS and SCD, while mechanisms peculiar to each disease may augment platelet adhesion in SCD and PNH. 相似文献48.
49.
Christophe Cassinotto Anthony Dohan Benoît Gallix Eve Simoneau Louis-Martin Boucher Peter Metrakos Tatiana Cabrera Carlos Torres Karl Muchantef David A. Valenti 《Journal of vascular and interventional radiology : JVIR》2017,28(7):963-970
Purpose
To assess frequency of adverse events, efficacy, and clinical outcomes of percutaneous portal vein embolization (PVE) in patients with bilobar colorectal liver metastases undergoing staged hepatectomy with preservation of segment IV ± I only.Materials and Methods
Retrospective analysis was performed of 40 consecutive patients who underwent right PVE after successful left lobectomy between 2005 and 2013. Rates of adverse events, future liver remnant (FLR) > 30% compared with baseline liver volume, clinical success (completion of staged hepatectomy with clearance of liver metastases), and overall survival were analyzed.Results
PVE was performed using polyvinyl alcohol particles (n = 7; 17.5%), particles plus coils (n = 23; 57.5%), and N-butyl cyanoacrylate glue plus ethiodized oil (n = 10; 25%). Technical success was 100%. After PVE, 20% (n = 8) of patients exhibited portal venous thrombosis, ranging from isolated intrahepatic portal branch thrombosis to massive thrombosis of the main portal vein (n = 3) and responsible for periportal cavernoma and portal hypertension in 5 patients. Of patients, 23 (57.5%) had FLR ≥ 30%, and 21 (52.5%) had clinical success. Six patients had significant stenosis or occlusion of the left portal vein or biliary system after original left lobectomy, which was independently associated with FLR < 30% (R2 = 0.24). Clinical success was the only independent variable associated with survival (R2 = 0.25).Conclusions
PVE for staged hepatectomy with preservation of segment IV ± I only is technically feasible, leading to adequate hypertrophy and clinical success rates in these patients with poor oncologic prognosis. Portal venous thrombosis is greater after the procedure than in the setting of standard PVE. 相似文献50.
Abrosimov A Saenko V Meirmanov S Nakashima M Rogounovitch T Shkurko O Lushnikov E Mitsutake N Namba H Yamashita S 《Endocrine pathology》2007,18(2):68-75
This study addressed the immunohistochemical expression of MUC1 in papillary thyroid carcinoma (PTC) of different histotypes,
sizes, and morphological features of aggressiveness, and its correlation with the overexpression of cyclin D1, a target molecule
of the Wnt pathway. MUC1 expression was examined in a total of 209 PTCs. Cytoplasmic MUC1 expression was elevated in the tall,
columnar cell and oncocytic variants (100%), Warthin-like (78%), and conventional PTCs (61%), and in papillary microcarcinoma
(PMC) with the conventional growth pattern (52%). On the contrary, it was low in the follicular variant (27%) of PTC and PMCs
with follicular architecture (13%). Cytoplasmic MUC1 accumulation did not associate with any clinicopathological features
except peritumoral lymphoid infiltration in PTCs and in PMCs with the conventional growth pattern. MUC1 staining correlated
with cyclin D1 overexpression in conventional PTCs and PMCs and PMCs with follicular architecture. The results demonstrate
that MUC1 expression varies broadly in different histological variants of PTC, being the lowest in tumors with follicular
structure. In general, it does not prove to be a prognosticator of PTC aggressiveness. A high correlation between MUC1 and
cyclin D1 implies MUC1 involvement in the Wnt cascade functioning in a large subset of human PTCs and PMCs. 相似文献