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991.
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Influence of Oxynitrided Surface in the Production of a Less Susceptible Titanium Surface to Skin‐Borne Bacterial Adhesion 下载免费PDF全文
Michelle de Medeiros Aires Janine Treter Danilo Cavalcante Braz Cristiano Krug Alexandre José Macedo Clodomiro Alves Júnior 《Artificial organs》2016,40(5):521-526
There is a growing quest for an ideal biomaterial that shows appropriate cellular response and is not susceptible to microbial adhesion. In this study, commercial grade II titanium was submitted to RF/DC plasma surface modification at 2.2 mbar, using gas mixtures of argon, nitrogen, and oxygen at proportions 4:1:2 and 4:1:3. The surfaces were physically and chemically characterized. In order to evaluate bacterial response, the surfaces were exposed to Staphylococcus epidermidis. Oxynitrided samples, although having a higher roughness as compared with untreated samples, exhibited lower bacterial growth. This observation is probably due to the formation of different crystalline phases of nitrides and oxides caused by plasma treatment. The surface with highest contact angle and highest surface tension showed lower bacterial adhesion. These results were confirmed by scanning electron microscopy. The role of nitrogen in reducing bacterial adhesion is clear when this material is compared with untreated titanium, on which only an oxide film is present. 相似文献
994.
The health care industry, in particular the hospital industry, is under an increasing degree of pressure, by an ageing population, advancing expensive medical technology a shrinking labor. The pressure on hospitals is further increased by the planned budget cuts in public spending by many current administrations as a result of the economic and financial crises. However, productivity increases may alleviate these problems. Therefore we study whether productivity in the hospital sector is growing, and whether this productivity growth can be influenced by government policy. Using an econometric time series analysis of the hospital sector in the Netherlands, productivity is estimated for the period 1972–2010. Then, productivity is linked to the different regulation regimes during that period, ranging from output funding in the 1970s to the current liberalized hospital market. The results indicate that the average productivity of the hospital sector in different periods differs and that these differences are related to the structure of regulation in those periods. 相似文献
995.
Ana Camba Elena Lendoiro Cristina Cordeiro Isabel Martínez-Silva María S. Rodríguez-Calvo Duarte N. Vieira José I. Muñoz-Barús 《Forensic science, medicine, and pathology》2014,10(4):627-633
In the field of legal medicine the correct determination of the time of death is of great importance because an error in calculating the post-mortem interval (PMI) could be crucial in a criminal investigation. The quantification of hypoxanthine (Hx) concentration in the vitreous humor (VH) as a means to estimate PMI is useful when dealing with a recent time interval of death and has several advantages over other biological matrices. However, due to its viscous nature, VH has to be liquefied prior to its analysis, and the different procedures to liquefy it may cause alterations in Hx concentration, and hence in estimation of PMI. The aim of this study was to determine differences in Hx concentration after applying several pre-analytical treatments to different aliquots of the same VH sample. Enzymatic digestion, sonication, centrifugation and heat were the liquefying methods applied to reduce the viscosity of 105 VH samples. Analysis was performed using solid phase extraction and liquid chromatography in tandem with mass spectrometry. Statistically significant differences in the measured Hx concentrations were found between enzymatic digestion and the other three methods analyzed (sonication, centrifugation, and heat). Additionally, high data dispersion was found under heat treatment but was not observed for centrifugation or sonication, where similar and more moderate results were found. We conclude that high variations in Hx determination are observed when enzymatic digestion or heat treatment is used and we therefore recommend sonication or centrifugation to quantify Hx concentration in the VH. 相似文献
996.
Rita Cabral Vera Teixeira Ana Brinca Barbara Fernandes José Pedro Reis 《Anais brasileiros de dermatologia》2014,89(1):167-168
Pemphigoid gestationis is a rare, autoimmune blistering dermatosis of pregnancy. No
increase in fetal or maternal mortality has been demonstrated, but a greater
prevalence of premature and small-for-gestationalage babies has been reported.
Topical and systemic corticosteroids and antihistamines are the manstay of treatment.
The authors report a case of a 27-year-old woman at 28-weeks gestation with sudden
onset of pruriginous vesicles and blisters in the abdomen and limbs. Systemic
corticosteroids were introduced and maintained throughout gestation to prevent flares
and tapered after the birth of a healthy child. 相似文献
997.
Cristiano V. M. Araújo Matilde Moreira-Santos José P. Sousa Valeria Ochoa-Herrera Andrea C. Encalada Rui Ribeiro 《Ecotoxicology (London, England)》2014,23(7):1254-1259
Several oil spills due to ruptures in the pipeline oil systems have occurred at the Andean paramo. A sample of this crude oil was mixed with water from a nearby Andean lagoon and the toxicity of the soluble fraction was assessed through lethal and avoidance assays with a locally occurring copepod (Boeckella occidentalis intermedia). The integration of mortality and avoidance aimed at predicting the immediate decline of copepod populations facing an oil leakage. The 24-h median lethal PAH concentration was 42.7 (26.4–91.6) µg L?1. In the 12-h avoidance assay, 30 % avoidance was recorded at the highest PAH concentration (19.4 µg L?1). The mortality at this PAH concentration would be of 25 % and, thus, the population immediate decline would be of 55 %. The inclusion of non-forced exposure testing with the quantification of the avoidance response in environmental risk assessments is, therefore, supported due to underestimation of the lethal assays. 相似文献
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999.
José I Quetglas Juan Dubrot Jaione Bezunartea Miguel F Sanmamed Sandra Hervas-Stubbs Cristian Smerdou Ignacio Melero 《Molecular therapy》2012,20(9):1664-1675
Intratumoral injection of Semliki Forest virus encoding interleukin-12 (SFV-IL-12) combines acute expression of IL-12 and stressful apoptosis of infected malignant cells. Agonist antibodies directed to costimulatory receptor CD137 (4-1BB) strongly amplify pre-existing cellular immune responses toward weak tumor antigens. In this study, we provide evidence for powerful synergistic effects of a combined strategy consisting of intratumoral injection of SFV-IL-12 and systemic delivery of agonist anti-CD137 monoclonal antibodies (mAbs), which was substantiated against poorly immunogenic B16 melanomas (B16-OVA and B16.F10) and TC-1 lung carcinomas. Effector CD8β+ T cells were sufficient to mediate complete tumor eradications. Accordingly, there was an intensely synergistic in vivo enhancement of cytotoxic T lymphocytes (CTL)-mediated immunity against the tumor antigens OVA and tyrosine-related protein-2 (TRP-2). This train of phenomena led to long-lasting tumor-specific immunity against rechallenge, attained transient control of the progression of concomitant tumor lesions that were not directly treated with SFV-IL-12 and caused autoimmune vitiligo. Importantly, we found that SFV-IL-12 intratumoral injection induces bright expression of CD137 on most tumor-infiltrating CD8+ T lymphocytes, thereby providing more abundant targets for the action of the agonist antibody. This efficacious combinatorial immunotherapy strategy offers feasibility for clinical translation since anti-CD137 mAbs are already undergoing clinical trials and development of clinical-grade SFV-IL-12 vectors is in progress. 相似文献
1000.