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991.
Ali Akbar Motedayen Mohammadreza Rezaeigolestani Carole Guillaume Valrie Guillard Nathalie Gontard 《RSC advances》2019,9(19):10938
The gas (O2 and CO2) permeability of an innovative stratified PE–organoclay (LLDPE/OMMT) nano-enabled composite films was studied for the first time and related to the self-assembly process driven by hydrophobic interactions. An 84.4% and a 70% reduction (i.e. a barrier improvement factor of about 6, sufficient for food packaging applications) were observed respectively in the oxygen and carbon dioxide permeability of the 5 bilayers coated film compared to the substrate, while only incorporating 2.4 v/v% of organoclay in the composite and increasing the thickness by 17.7%. Such drastic effect with so low amount of organoclays cannot be achieved by conventional melt blending/exfoliation of the clays into the polymer matrix and is due to a geometrical blocking effect of a brick-wall and compact layer structure of the impermeable clay tactoids. Mathematical prediction of oxygen barrier performance of PE/OMMT films has revealed that 12 bilayers would be necessary to further achieve a barrier improvement factor of 10.The gas (O2 and CO2) permeability of an innovative stratified PE–organoclay (LLDPE/OMMT) nano-enabled composite films was studied for the first time and related to the self-assembly process driven by hydrophobic interactions. 相似文献
992.
Nathalie Dunkel Ilker Uçkay Wilson Belaieff Mathieu Assal Valentina Corni Alain Lacraz Şaziye Karaca 《Journal of orthopaedic science》2012,17(5):588-594
BackgroundOptimal duration of antibiotic prophylaxis following major lower limb amputation in preventing adverse stump outcomes is controversial.ObjectiveWe assess the epidemiology and risk factors of wound dehiscence and stump infection after mid-thigh to transmetatarsal amputations with regard to antibiotic administration.MethodsOur retrospective observational study at the Geneva University Hospital (January 1995–June 2010) includes a total of 289 amputations in 270 adult patients (199 males; median age 70 years).ResultsWound dehiscence and/or stump infection occurred in 47 (16.3 %) and 63 (21.8 %) patients with a median delay of 24 and 14 days, respectively. No clinical variable was significantly associated with stump infection. Diabetes and older age (>80 years) were associated with dehiscence. Importantly, transcutaneous tissue oxygen tension (TcPO2) and duration of antibiotic administration showed no association with either outcome.ConclusionThe duration of antibiotic administration before or after surgery does not change the epidemiology of stump complications. 相似文献
993.
Verhoeven JS Rommel N Prodi E Leemans A Zink I Vandewalle E Noens I Wagemans J Steyaert J Boets B Van de Winckel A De Cock P Lagae L Sunaert S 《Cerebral cortex (New York, N.Y. : 1991)》2012,22(10):2263-2271
Discussion of an overlap between specific language impairment (SLI) and autism spectrum disorder (ASD) is on going. The most intriguing overlap between both phenotypes is the similarity in the observed language deficits described in SLI and a subgroup of ASD with co-occurring linguistic impairment, ASD-LI. Examining whether a similar neuroanatomical substrate underlies this phenotypical linguistic overlap, we studied the white matter microstructural properties of the superior longitudinal fascicle (SLF) of 19 ASD-LI adolescents (mean age 13.8 ± 1.6 years) and 21 age-matched controls and compared them with 13 SLI children (mean age 10.1 ± 0.4 years) and 12 age-matched controls. A linguistic profile assessment and a diffusion tensor imaging analysis of the SLF were performed. Linguistic testing revealed a mixed receptive-expressive disorder profile in both groups, confirming their overlap at phenotypical level. At neuroanatomical level, no significant differences in mean SLF fractional anisotropy (FA) and mean SLF apparent diffusion coefficient values between ASD-LI participants and controls were seen. By contrast, the mean SLF FA was significantly reduced in the SLI children as compared with their controls. The observation of structural SLF disturbances in SLI but not in ASD-LI suggests the existence of a different neuroanatomical substrate for the language deficits in both disorders. 相似文献
994.
Recent advances in genetics and oncology have led to development of a wide array of molecular therapeutics in the management
of patients with metastatic renal cell carcinoma. These drugs have revolutionized the treatment of advanced disease by significantly
improving patient outcomes. State-of-the-art cross-sectional imaging techniques play a seminal role in the evaluation of treatment
response by providing reproducible, objective data, thereby permitting accurate quantification of tumor burden. Evolving functional
imaging techniques such as perfusion and diffusion studies continue to advance the technology beyond assessing changes in
tumor size and morphology. 相似文献
995.
997.
Significant scientific advances have been made over the last five years in the pathogenesis of hyperuricemia and understanding how monosodium urate (MSU) crystals provoke gout. New detection methods using ultrasound (US) have been evaluated and may become part of our routine diagnostic approach in a patient presenting with gout. This review will concentrate on the latest developments in the field, and discuss how these data may impact on clinical practice. Finally, a brief review of the therapeutic implications and new therapies that have become available will be presented. 相似文献
998.
Maurel DB Boisseau N Benhamou CL Jaffré C 《Joint, bone, spine : revue du rhumatisme》2012,79(5):492-499
ObjectiveWhile chronic alcohol consumption is known to decrease bone mineral content (BMC), bone mineral density (BMD), and negatively modify trabecular bone microarchitecture, the impact of alcohol on cortical microarchitecture is still unclear. The aim of this study was to investigate the effects of various doses of alcohol on bone density, trabecular and cortical parameters and bone strength in rats.MethodsForty-eight male Wistar rats were divided into four groups: control (C), alcohol 25% v/v (A25), alcohol 30% v/v (A30) and alcohol 35% v/v (A35). Rats in the alcohol groups were fed a solution composed of ethanol and water for 17 weeks while the control group drank only water. Bone quality and quantity were evaluated through the analysis of density, trabecular and cortical bone microarchitectural parameters, osteocalcin and N-Telopeptide concentrations and a 3-point bending test.ResultsBone density along with trabecular and cortical thickness were lower in alcohol groups compared to C. BMD was lower in A35 vs. A30 and cortical thickness was lower in A35 vs. A25 and A30. Pore number was increased by alcohol and the porosity was greater in A35 compared to C. N-Telopeptide concentration was decreased in alcohol groups compared to control whereas no differences were observed in osteocalcin concentrations. Maximal energy to failure was lower in A25 and A35 compared to C.ConclusionChronic ethanol consumption increases cortical bone damage in rats and may have detrimental effects on bone strength. These effects were dose-dependent, with greater negative effects proportionate to greater alcohol doses. 相似文献
999.
Nathalie Duroseau Miranda Loh Leslie Sanders Martha Arden 《Journal of pediatric and adolescent gynecology》2021,34(2):226-227
BackgroundSeveral states have deemed abortions as nonessential services, effectively calling for a halt to abortion care during the COVID-19 pandemic. In response, women might elect for self-managed abortions by obtaining abortion medications online.CaseA 15-year-old girl presented with abdominal cramping and vaginal discharge after taking misoprostol obtained from an online retailer for a self-managed abortion in her second trimester during the COVID-19 pandemic. Her exam showed products of conception protruding from the vagina. The patient was emergently evaluated for an incomplete and possible septic abortion and underwent a dilation and evacuation procedure. 相似文献
1000.