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Diamond-like carbon (DLC) films have received much attention recently owing to their properties, which are similar to diamond: hardness, thermal conductivity, corrosion resistance against chemicals, abrasion resistance, good biocompatibility, and uniform flat surface. Furthermore, DLC films can be deposited easily on many substrates for wide area coat at room temperature. DLC films were developed for applications as biomedical materials in blood contacting-devices (e.g., rotary blood pump) and showed good biocompatibility for these applications. In this study, we investigated the surface roughness by Atomic Force Microscopy (AFM) and Hi-vision camera, SEM for surface imaging. The DLC films were produced by radio frequency glow discharge plasma decomposed of hydrocarbon gas at room temperature and low pressure (53 Pa) on several kinds of polycarbonate substrates. For the evaluation of the relation between deposition rate and platelet adhesion that we investigated in a previous study, DLC films were deposited at the same methane pressure for several deposition times, and film thickness was investigated. In addition, the deposition rate of DLC films on polymeric substrates is similar to the deposition rate of those deposited on Si substrates. There were no significant differences in substrates' surface roughness that were coated by DLC films in different deposition rates (16-40 nm). The surface energy and the contact angle of the DLC films were investigated. The chemical bond of DLC films also was evaluated. The evaluation of surface properties by many methods and measurements and the relationship between the platelet adhesion and film thickness is discussed. Finally, the presented DLC films appear to be promising candidates for biomedical applications and merit investigation.  相似文献   
3.
葛根素的心血管系统药理作用及机理研究   总被引:27,自引:1,他引:27  
纵观近年来对葛根素在心血管系统药理作用及机理研究方面的进展发现,葛根素对心血管系统具有抗心律失常、降血压、扩张冠状动脉、抗心肌缺血、抗过氧化、抗缺血-再灌注损伤、影响血液动力学和血小板聚集、保护血管等作用。其临床应用前景良好,其药效机制研究及临床应用有待更深一步的探究。  相似文献   
4.
This study assesses the retreatability of TotalFill bioceramic (TFBC) and AH Plus (AHP) sealers and their impact on retreatment force and torque. Twenty-six premolar teeth with single oval canals were instrumented, obturated using the matched gutta-percha cone technique with one of the tested sealers, and then temporized. After a 6-month incubation at 37 °C and 100% humidity, the canals were retreated with the XP Shaper system. During retreatment, the generated force and torque were measured. Micro-CT scanning was run before and after the retreatment procedure to analyze the remaining obturating materials in the canals. The apically directed maximum force in AHP was higher than that in TFBC. The coronally directed maximum force and the maximum torque were comparable between the groups. A higher amount of remaining obturating materials was found in the AHP compared to that in the TFBC. Based on these findings, endodontic sealer had an influence on retreatability, and the TFBC showed less remaining obturating materials and lower retreatment forces in the apical direction compared to the AHP in extracted teeth with oval canals.  相似文献   
5.
BackgroundAn aberrant expression of long non‐coding RNA PVT1 has been associated with apoptosis in various cancer types. We aimed to explore the PVT1 and four apoptosis‐related proteins (p53, Bcl2, and PD‐1/PD‐L1) signature in thyroid cancer (TC).MethodsThe PVT1 expression level was measured in 64 FFPE TC paired samples by real‐time quantitative PCR. Overall and stratified analyses by different clinicopathological features were done. The apoptotic proteins were evaluated by immunohistochemistry staining.ResultsOverall analysis showed significant PVT1upregulation in TC tissues (p < 0.001). Similarly, subgroup analysis by BRAF V600E mutation showed consistent results. Lower expression of p53 was associated with mortality (p = 0.001). Bcl2 overexpression was associated with greater tumor size (p = 0.005). At the same time, HCV‐positive cases were associated with repressed Bcl2 expression levels (54.3% in HCV‐negative vs. 6.9% in HCV‐positive cases, p = 0.011). PD‐1 expression was associated with lymph node metastasis (p = 0.004). Enhanced PD‐L1 expression in the tumor was associated with a higher tumor stage, lymphovascular invasion, and mortality risk. Kaplan–Meier curves for overall survival showed that low p53 and high PD‐L1 expressions were associated with lower survival time. The p53‐positive staining is associated with a 90% decreased mortality risk (HR = 0.10, 95%CI = 0.02–0.47, p = 0.001), while patients with high PD‐L1 were five times more likely to die (HR = 4.74, 95%CI = 1.2–18.7, p = 0.027).ConclusionOur results confirm the upregulation of PVT1 in TC. The apoptosis‐related proteins (p53, Bcl2, and PD‐1/PD‐L1) showed different prognostic utility in TC patients; in particular, low p53 and high PD‐L1 expressions associated with low survival times. Further large‐scale and mechanistic studies are warranted.  相似文献   
6.
ObjectiveThis study investigated the role of objective olfactory dysfunction (OD) and gustatory dysfunction (GD) testing among patients with suspected coronavirus disease 2019 (COVID-19) who presented with respiratory symptoms.MethodsA prospective, blinded, observational study was conducted in the emergency units of two tertiary hospitals. Participants were asked to identify scents in the pocket smell test (PST) and flavors in four different solutions in the gustatory dysfunction test (GDT). We assessed the level of agreement between objective findings and self-reported symptoms. We evaluated the diagnostic accuracy of chemosensory dysfunction for diagnosing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.ResultsOf 250 participants, 74 (29.6%) were SARS-CoV-2-positive. There was slight agreement between self-reported symptoms and objective findings (kappa = 0.13 and 0.10 for OD and GD, respectively). OD assessed by the PST was independently associated with COVID-19 (adjusted odds ratio = 1.89, 95% confidence interval, 1.04–3.46). This association was stronger when OD was combined with objective GD, cough, and fever (adjusted odds ratio = 7.33, 95% confidence interval, 1.17–45.84).ConclusionsNeither the PST nor GDT alone are useful screening tools for COVID-19. However, a diagnostic scale based on objective OD, GD, fever, and cough may help triage patients with suspected COVID-19.  相似文献   
7.
Plackett–Burman randomization method is a conventional tool for variables randomization aiming at optimization. Bacterial Ghosts (BGs) preparation has been recently established using methods other than the E lysis gene. The protocol has been based mainly on using critical concentrations from chemical compounds able to convert viable cells to BGs. The Minimum Inhibition Concentration (MIC) and the Minimum Growth Concentration (MGC) were the main guide for the BGs preparation. In this study, Escherichia coli JM109 DEC has been used to produce the BGs following the original protocol. The study contained a detail protocol for BGs preparation that could be used as a guide.  相似文献   
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Conjugation of cholesterol moiety to active compounds for either cancer treatment or diagnosis is an attractive approach. Cholesterol derivatives are widely studied as cancer diagnostic agents and as anticancer derivatives either in vitro or in vivo using animal models. In largely growing studies, anticancer agents have been chemically conjugated to cholesterol molecules, to enhance their pharmacokinetic behavior, cellular uptake, target specificity, and safety. To efficiently deliver anticancer agents to the target cells and tissues, many different cholesterol–anticancer conjugates were synthesized and characterized, and their anticancer efficiencies were tested in vitro and in vivo.  相似文献   
10.
Metabolic syndrome (MetS) is a cluster of cardiovascular risk factors including obesity, hypertension, dyslipidemia and hyperuricemia. Here, we report a 43-year-old man with obesity, hypertension, hypercholesterolemia, hyperuricemia and mild liver dysfunctions. Lupid (Lupineus luteus) and therapeutic lifestyle change (TLC) were suggested as therapeutic intervention for the present case for 6 months. The body weight, body mass index (BMI), blood pressure, total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), triacylglycerol (TAG), uric acid (UA) and alanine transaminase (ALT) were markedly decreased by 26.85%, 26.95%, 13%, 53.84%, 57.84%, 36.14%, 47.58% and 61.62% respectively, compared to those at baselines. However, high density lipoprotein cholesterol (HDL-C) value was markedly increased by 30.77%. The present results concluded that administration of lupin with TLC is good intervention for prevention and treatment of MetS.  相似文献   
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