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91.
《Substance use & misuse》2013,48(14):2065-2086
This paper examines the relationship between drug use and violence among representative samples of students in the United States and Ontario, Canada. Canada has significantly lower levels of violent crime than the United States, but students report similar rates of drug use. Using logistic regression analysis, we find a similar relationship between drug use and violence among adolescents in the two countries. All the drugs considered—cannabis, cocaine, and alcohol binge drinking—are significantly related to violent behavior; whether the perpetrator or the victim. The most noteworthy difference may be that in Ontario, drug use appears to be even more highly correlated with violence than in the United States.  相似文献   
92.
Our understanding of the function of vitellogenin (Vg) in reproduction has undergone a transformation over the past decade in parallel with new insights into the role of Vg in immunity. However, the time when Vg was endowed with immunological activities during animal evolution remains elusive. Here we demonstrate for the first time that the recombinant proteins rVitellogenin_N, rDUF1943, and rVWD from Vg of the basal metazoan coral Euphyllia ancora not only interact with Gram-positive and negative bacteria as well as their conserved surface components LTA and LPS but also enhance phagocytosis of bacteria by macrophages. Moreover, challenge with LPS results in a marked up-regulation of vg in the coral E. ancora. These data suggest that E. ancora Vg, like that described in the bilaterian oviparous animals fish and amphioxus, is a molecule related to antibacterial defense, indicating that the timing of the emergence of immune role of Vg predates the divergence of the cnidarian (non-bilaterian) and bilaterian lineages.  相似文献   
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目的 为了初步了解广藿香酮抗金黄色葡萄球菌(Staphylococcus aureus)的分子机制。方法 本研究用琼脂稀释法测定广藿香酮的药物敏感性,通过对金黄色葡萄球菌ATCC25923在1倍最低抑菌浓度(minimum inhibitory concentration, MIC)广藿香酮药物浓度作用1h时进行转录组的高通量测序然后对数据进行KEGG(kyoto encyclopedia of genes and genomes)和GO(gene ontology)差异基因表达以及热图聚类分析。结果 药敏实验发现广藿香酮对金黄色葡萄球菌有抑制活性,经广藿香酮处理后,筛选出225个差异表达的基因,发现广藿香酮使金黄色葡萄球菌膜蛋白的表达、蛋白质的合成发生变化,并且使葡萄糖以及多糖的转运和合成受到控制。结论 广藿香酮可能与金黄色葡萄球菌的细胞膜蛋白相互作用从而抑制细菌生长,为进一步的实验提供数据支持。  相似文献   
96.
《Acta oto-laryngologica》2012,132(5):569-579
This paper reviews the medical literature of the last decade to ascertain the criteria used to assess mandibular invasion by cancer of the oral cavity and to suggest how best to evaluate the mandible with a view to surgical management. It is generally agreed that patients with mandibular invasion should be treated surgically, but the extent of mandibular resection required remains a controversial matter and the accurate preoperative determination of neoplastic invasion of the mandible remains a challenge for head and neck surgeons. The relative reliability of preoperative orthopantomography, (OPG) bone scanning, computed tomography (CT) and magnetic resonance imaging (MRI), and of peroperative periosteal stripping and direct inspection in clinical assessment for mandibular surgery, is discussed. The histological patterns of tumor invasion and the most common routes of tumor entry in the mandible are described and the influence of variables such as prior radiotherapy and an edentulous vs a dentate state in relation to perineural invasion are also discussed. Finally, a comparison is drawn between the reported outcome of marginal vs segmental resection procedures and a decision-making algorithm is proposed. In selected cases, marginal mandibulectomy can ensure satisfactory tumor control, with a favorable effect on the morbidity associated with mandibular surgery.  相似文献   
97.
《Acta oto-laryngologica》2012,132(1):25-27
Conclusion. Our technique can decrease the formation of retraction pockets and improve hearing function. The wheel-shaped cartilage-perichondrium composite graft (Wheel CPCG) can be considered a good material for a drum graft, and it is easy to insert a ventilation tube, in case of initial drum retraction. Objective. The purpose of this study was to introduce the novel surgical technique of a Wheel CPCG with one-stage ossiculoplasty to prevent a retraction pocket and subsequent cholesteatoma after intact canal wall tympanomastoidectomy. Patients and methods. A total of 47 patients were reviewed; 43 cases were selected for audiologic testing. The results of operations were evaluated by comparing preoperative and postoperative hearing results and postoperative drum findings. Results. A retraction pocket was observed in three cases (6.7%). Slight protrusion of partial ossicular replacement prosthesis (PORP) and lateral healing of drum was observed in one case each, and there were two cases of postoperative infection. The number of cases with an air–bone gap (ABG)<20 dB increased from 9 (23%) cases before operation, to 20 cases (51%) after operation. The ABG average statistically decreased from 30.0 dB to 24.0 dB, and the mean air conduction thresholds decreased from a preoperative level of 47.3 dB to a level of 35.7 dB.  相似文献   
98.
《Acta oto-laryngologica》2012,132(8):957-962
Non-steroidal anti-inflammatory drugs (NSAIDs) can inhibit tumorigenesis in colorectal cancer due to the induction of apoptosis. Disturbances of cellular pathways ultimately leading to apoptosis may contribute to the process of neoplastic transformation and immortalization. In this study we wanted to determine the influence of different NSAIDs (indomethacin, ibuprofen and sodium salicylate) and hydrocortisone on Bcl-2 expression and the apoptotic behavior of head and neck tumor cell lines and normal oral keratinocytes. Bcl-2 expression was determined by monoclonal antibody staining and fluorescence-activated cell-sorting measurement. Apoptotic cells were visualized with a epifluorescence microscope after staining with CytoDeath M30 antibody. Indomethacin (1 mM) and ibuprofen (1 mM) significantly reduced Bcl-2 expression in the cancer cell lines tested and might be thought responsible for the observed increase in apoptosis. At all concentrations tested the influence of sodium salicylate and hydrocortisone on Bcl-2 expression was not significant. In contrast, the NSAIDs tested had only a minor influence on normal oral keratinocytes. Our results demonstrate a significant reduction in growth and an increase in apoptosis, possibly due to a reduction in Bcl-2 expression, after exposure to indomethacin and ibuprofen in the head and neck cancer cell lines tested.  相似文献   
99.
For effective antibacterial therapy, physicians require qualitative test results using susceptibility breakpoints provided by clinical microbiology laboratories. This article summarizes the key components used to establish the Clinical Laboratory Standards Institute (CLSI) breakpoints for tedizolid. First, in vitro studies using recent surveillance and clinical trial isolates ascertained minimal inhibitory concentration (MIC) distributions against pertinent organisms, including staphylococci, streptococci, and enterococci. Studies in animal models of infection determined rates of antibacterial efficacy and survival following administration of tedizolid phosphate at doses equivalent to those in humans. Pharmacokinetic and pharmacodynamic analyses examined the relationship between plasma concentrations and MICs against the target organism. Finally, clinical trials assessed clinical and microbiologic outcomes by MIC. All these data were evaluated and combined to obtain the ratified CLSI susceptibility criteria for tedizolid of ≤0.5 μg/mL for Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, and Enterococcus faecalis and ≤0.25 μg/mL for Streptococcus anginosus group.  相似文献   
100.
《Dental materials》2019,35(8):1155-1165
ObjectiveThe aim of this study was to formulate and evaluate experimental orthodontic adhesives with different concentrations of 1-n-butyl-3-methylimidazoilium bis(trifluoromethanesulfonyl)imide (BMIM.NTf2).MethodsThe experimental orthodontic adhesives were formulated with methacrylate monomers, photoinitiators and silica colloidal. The ionic liquid BMIM.NTf2 was synthesized and characterized. BMIM.NTf2 was added at 5 (G5%), 10 (G10%) and 15 (G15%) wt.%. One group contained no BMIM.NTf2 to function as control (GCtrl). The adhesives were evaluated for polymerization kinetics, degree of conversion (DC), Knoop hardness and softening in solvent, ultimate tensile strength (UTS), shear bond strength (SBS), thermogravimetric analysis (TGA), antibacterial activity and cytotoxicity.ResultsBMI.NTf2 showed the characteristic chemical peaks. The polymerization kinetics were different among the groups. G10% and G15% showed higher DC (p < 0.05). G5% and GCtrl had no differences for softening in solvent (p > 0.05). There were no differences for UTS (p > 0.05) and SBS (p > 0.05). TGA showed one different peak for G15%. All groups with BMIM.NTf2 showed antibacterial activity compared to GCtrl (p < 0.05) without cytotoxicity (p > 0.05).SignificanceTo reduce biofilm formation around brackets and to prevent demineralization at susceptible sites, materials have been developed with antibacterial properties. In this study, a new experimental orthodontic adhesive was formulated with an imidazolium ionic liquid (BMIM.NTf2) as antibacterial agent. The incorporation of 5 wt.% of ionic liquid decreased biofilm formation without affecting the physico-chemical properties and cytotoxicity of an experimental orthodontic resin.  相似文献   
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