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991.
992.

Objective

To evaluate the surface and wettability characteristics and the microbial biofilm interaction of graphene coating on titanium.

Methods

Graphene was deposited on titanium (Control) via a liquid-free technique. The transfer was performed once (TiGS), repeated two (TiGD) and five times (TiGV) and characterized by AFM (n = 10), Raman spectroscopy (n = 10), contact angle and SFE (n = 5). Biofilm formation (n = 3) to Streptococcus mutans, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans was evaluated after 24 h by CV assay, CFU, XTT and confocal microscopy. Statistics were performed by one-way Anova, Tukey’s tests and Pearson’s correlation analysis at a pre-set significance level of 5 %.

Results

Raman mappings revealed coverage yield of 82 % for TiGS and ≥99 % for TiGD and TiGV. Both TiGD and TiGV presented FWHM > 44 cm?1 and ID/IG ratio < 0.12, indicating multiple graphene layers and occlusion of defects. The contact angle was significantly higher for TiGD and TiGV (110° and 117°) comparing to the Control (70°). The SFE was lower for TiGD (13.8 mN/m) and TiGV (12.1 mN/m) comparing to Control (38.3 mN/m). TiGD was selected for biofilm assays and exhibited significant reduction in biofilm formation for all microorganisms compared to Control. There were statistical correlations between the high contact angle and low SFE of TiGD and decreased biofilm formation.

Significance

TiGD presented high quality and coverage and decreased biofilm formation for all species. The increased hydrophobicity of graphene films was correlated with the decreased biofilm formation for various species.  相似文献   
993.
994.
995.
996.

Purpose

The purpose of our study was to test a new staging algorithm, combining clinical TNM staging (cTNM) with whole-body metabolic active tumor volume (MATV-WB), with the goal of improving prognostic ability and stratification power.

Methods

Initial staging [18F]FDG PET/CT of 278 non-small cell lung cancer (NSCLC) patients, performed between January/2011 and April/2016, 74(26.6%) women, 204(73.4%) men; aged 34-88 years (mean ± SD:66 ± 10), was retrospectively evaluated, and MATV-WB was quantified. Each patient’s follow-up time was recorded: 0.7-83.6 months (mean ± SD:25.1 ± 20.3).

Results

MATV-WB was an independent and statistically-significant predictor of overall survival (p < 0.001). The overall survival predictive ability of MATV-WB (C index: mean ± SD = 0.7071 ± 0.0009) was not worse than cTNM (C index: mean ± SD = 0.7031 ± 0.007) (Z = ?0.143, p = 0.773). Estimated mean survival times of 56.3 ± 3.0 (95%CI:50.40-62.23) and 21.7 ± 2.2 months (95%CI:17.34-25.98) (Log-Rank = 77.48, p < 0.001), one-year survival rate of 86.8% and of 52.8%, and five-year survival rate of 53.6% and no survivors, were determined, respectively, for patients with MATV-WB < 49.5 and MATV-WB ≥ 49.5. Patients with MATV-WB ≥ 49.5 had a mortality risk 2.9-5.8 times higher than those with MATV-WB < 49.5 (HR = 4.12, p < 0.001). MATV-WB cutoff points were also determined for each cTNM stage: 23.7(I), 49.5(II), 52(III), 48.8(IV) (p = 0.029, p = 0.227, p = 0.025 and p = 0.001, respectively). At stages I, III and IV there was a statistically-significant difference in the estimated mean overall survival time between groups of patients defined by the cutoff points (p = 0.007, p = 0.004 and p < 0.001, respectively). At stage II (p = 0.365), there was a clinically-significant difference of about 12 months between the groups. In all cTNM stages, patients with MATV-WB ≥ cutoff points had lower survival rates. Combined clinical TNM-PET staging (cTNM-P) was then tested: Stage I < 23.7; Stage I ≥ 23.7; Stage II < 49.5; Stage II ≥ 49.5; Stage III < 52; Stage III ≥ 52; Stage IV < 48.8; Stage IV ≥ 48.8. cTNM-P staging presented a superior overall survival predictive ability (C index = 0.730) compared with conventional cTNM staging (C index = 0.699) (Z = ?4.49, p < 0.001).

Conclusion

cTNM-P staging has superior prognostic value compared with conventional cTNM staging, and allows better stratification of NSCLC patients.
  相似文献   
997.
Presentation of a cerebral aneurysm can be incidental, discovered at imaging obtained for unrelated causes, can occur in the occasion of imaging obtained for symptoms possibly or likely related to the presence of an unruptured aneurysm, or can occur with signs and symptoms at the time of aneurismal rupture.  相似文献   
998.
BACKGROUND: The aim of this study is to analyze the effects of dobutamine (DBT) on pulmonary and systemic hemodynamics and oxygenation in lung transplant candidates. METHODS: Forty-five patients (21M, 24F) to be introduced in waiting list for lung transplantation were studied (14 pulmonary fibrosis, 15 COPD, and 16 cystic fibrosis). They were studied awake, while spontaneously breathing in two different phases: baseline--O2 100%; DBT phase--O2 100% after 10 minutes of DBT continuous infusion (10 mcg/Kg/min). Blood gas samples and hemodynamic data were collected during right heart catheterization. Data were statistically analyzed with Student's "t" test and values for p < 0.05 were considered as significant. RESULTS: During DBT phase, a significant increase of cardiac output with a decreasing in systemic and pulmonary vascular resistance was observed. Since the fall in pulmonary vascular resistance (PVRI) was not proportional to the increase of cardiac output, mean pulmonary artery pressure and transpulmonary gradient increased. The prevalent role of vascular recruitment as mechanism in PVRI reduction during DBT is supported by the concomitant fall in PaO2/FiO2. This strongly suggests a worsening of regional Va/Qc due to an increased perfusion of poorly ventilated areas. CONCLUSIONS: DBT reduces PVRI through a recruitment of vessels due to an increase of pulmonary flow. Dobutamine has a favorable hemodynamic effect in mild-to-moderate pulmonary hypertension in lung transplant candidates.  相似文献   
999.
Hyperacute rejection (HAR) remains a critical immunologic hurdle in the development of xenogeneic organs for human transplantation. Strategies that simultaneously eliminate both natural antibody reactivity and complement activation on the xenogeneic cell surface may be the best approach to achieve clinical application of xenogeneic vascularized organ transplantation. We have developed multiple lines of genetically manipulated mice to evaluate the combination of different genetic approaches aimed at inhibiting antibody and complement-mediated cell lysis. We utilized transgenic mice expressing the human complement inhibitor, CD59, the human 1,2-fucosyltransferase (H-transferase, HT) and the α1,3-galactosyltransferase (α1,3-GT) knock-out mouse line (Gal KO). Our data show that expression of hCD59 in combination with HT expression or the null phenotype of α1,3-GT are equally effective at preventing human serum-mediated cytolysis. Interestingly, the triple combination affords no additional protective effect. Therefore, coexpression of HT and a complement inhibitor is the most immediate strategy to genetically engineer transgenic pigs to be used as xenogeneic donors.  相似文献   
1000.
Bone Mineral Density and Androgen Levels in Elderly Males   总被引:4,自引:0,他引:4  
To clarify the relationship of sex male hormones and bone in men, we studied in 140 healthy elderly men (aged 55–90 years) the relation between serum levels of androgens and related sex hormones, bone mineral density (BMD) at different sites, and other parameters related to bone metabolism. Our results show a slight decrease of serum-free testosterone with age, with an increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in a third of the elderly subjects studied. BMD decreased significantly with age in all regions studied, except in the lumbar spine. We found a positive correlation between body mass index (BMI) and BMD at the lumbar spine and femoral neck (P < 0.001). No relationship was found (uni- and multivariate regression analysis) between serum androgens or sex hormone-binding globulin (SHBG) and BMD. We found a positive correlation of vitamin D binding protein (DBP) and osteocalcin with lumbar spine BMD and with BMI, DBP, IGF-1, and PTH with femoral neck BMD. In conclusion, there is a slight decline in free testosterone and BMD in the healthy elderly males. However, sex male hormones are not correlated to the decrease in hip BMD. Other age-related factors must be associated with bone loss in elderly males. Received: 29 April 1997 / Accepted: 9 November 1997  相似文献   
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