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To date, the number of cases reported after exposure to mifepristone alone in early pregnancy is limited. In 24 cases, only 1 observation of fetal malformation associated with mifepristone has previously been reported. We report a case of amniotic band syndrome with limb amputation after exposure to mifepristone in early pregnancy. This association raises the question of a possible causal relationship.  相似文献   
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BackgroundWest Nile virus (WNV) and Usutu virus (USUV), two closely related flaviviruses, mainly follow an enzootic cycle involving mosquitoes and birds, but also infect humans and other mammals. Since 2010, their epidemiological situation may have shifted from irregular epidemics to endemicity in several European regions; this requires confirmation, as it could have implications for risk assessment and surveillance strategies.AimTo explore the seroprevalence in animals and humans and potential endemicity of WNV and USUV in Southern France, given a long history of WNV outbreaks and the only severe human USUV case in France in this region.MethodsWe evaluated the prevalence of WNV and USUV in a repeated cross-sectional study by serological and molecular analyses of human, dog, horse, bird and mosquito samples in the Camargue area, including the city of Montpellier, between 2016 and 2020.ResultsWe observed the active transmission of both viruses and higher USUV prevalence in humans, dogs, birds and mosquitoes, while WNV prevalence was higher in horses. In 500 human samples, 15 were positive for USUV and 6 for WNV. Genetic data showed that the same lineages, WNV lineage 1a and USUV lineage Africa 3, were found in mosquitoes in 2015, 2018 and 2020.ConclusionThese findings support existing literature suggesting endemisation in the study region and contribute to a better understanding of USUV and WNV circulation in Southern France. Our study underlines the importance of a One Health approach for the surveillance of these viruses.  相似文献   
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Mussels have been proposed as biomonitors of metal pollution based on the determination of metallothionein (MT) concentrations as a biomarker, but a comprehensive study taking into account both intersite and long-term temporal variations in MT and metal concentrations in different organs is lacking. Thus, the present study was designed to examine the concentrations of cytosolic and insoluble Cd, Cu, Zn, and MT in gills and digestive gland of mussels (Mytilus edulis) of homogeneous size and age obtained from aquaculture and kept on a reference site or translocated to a metal-rich site throughout their reproductive season (March-October 1997). Relatively significant binding of metals to the insoluble fraction was observed in both tissues. In the digestive gland, monthly MT concentrations were strongly correlated to cytosolic metal levels. Moreover, despite significant temporal variations, the grand mean MT concentration based on all individual determinations in the digestive gland (reference, n=54; transplants, n=50) was significantly higher in mussels from the metal-rich site. On the other hand, gill MT concentrations did not reflect metal contamination as reliably.  相似文献   
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High-Pressure (HP) technology allows new possibilities of processing by Spark Plasma Synthesis (SPS). This process is mainly involved in the sintering process and for bonding, growing and reaction. High-Pressure tools combined with SPS is applied for processing polycrystalline diamond without binder (binderless PCD) in this current work. Our described innovative Ultra High Pressure Spark Plasma Sintering (UHP-SPS) equipment shows the combination of our high-pressure apparatus (Belt-type) with conventional pulse electric current generator (Fuji). Our UHP-SPS equipment allows the processing up to 6 GPa, higher pressure than HP-SPS equipment, based on a conventional SPS equipment in which a non-graphite mold (metals, ceramics, composite and hybrid) with better mechanical properties (capable of 1 GPa) than graphite. The equipment of UHP-SPS and HP-SPS elements (pistons + die) conductivity of the non-graphite mold define a Hot-Pressing process. This study presents the results showing the ability of sintering diamond powder without additives at 4–5 GPa and 1300–1400 °C for duration between 5 and 30 min. Our described UHP-SPS innovative cell design allows the consolidation of diamond particles validated by the formation of grain boundaries on two different grain size powders, i.e., 0.75–1.25 μm and 8–12 μm. The phenomena explanation is proposed by comparison with the High Pressure High Temperature (HP-HT) (Belt, toroidal-Bridgman, multi-anvils (cubic)) process conventionally used for processing binderless polycrystalline diamond (binderless PCD). It is shown that using UHP-SPS, binderless diamond can be sintered at very unexpected P-T conditions, typically ~10 GPa and 500–1000 °C lower in typical HP-HT setups. This makes UHP-SPS a promising tool for the sintering of other high-pressure materials at non-equilibrium conditions and a potential industrial transfer with low environmental fingerprints could be considered.  相似文献   
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BACKGROUND: The renal reabsorption of natural nucleosides and a variety of nucleoside-derived drugs relies on the function of the apically located, Na(+)-dependent, concentrative nucleoside transporters CNT1, CNT2, and CNT3 (SLC28A1, SLC28A2, and SLC28A3). The aims of this study were to determine the segmental localization of the three SLC28 family members and to establish whether streptozotocin-induced diabetes alters their expression. METHODS: SLC28 expression was measured by real-time polymerase chain reaction (PCR) on microdissected sections of rat nephrons. Diabetes was induced by streptozotocin treatment and the biochemical profiles of control, diabetic, and insulin-treated rats were established. The effect of diabetes on SLC28 expression was assessed in those segments that significantly express SLC28 genes. RESULTS: CNT1-3 mRNAs were expressed in the proximal tubule and glomerulus. In addition, CNT2 and CNT3 mRNAs were expressed in the outer medullary and cortical collecting duct, respectively. Diabetes reduced expression of the three CNTs in almost all nephron segments, and this effect was not prevented by an insulin treatment that normalized all blood and urine parameters. Diabetes increased CNT1 and CNT3 expression in the glomerulus and insulin treatment decreased it. CONCLUSION: The relative distribution of SLC28 gene expression suggests a role for the proximal tubule in renal nucleoside clearance and an accessory role for CNT2 and CNT3, in adenosine-mediated regulation of collecting duct functions. Diabetes probably may impair nucleoside clearance independently of insulin.  相似文献   
128.
目的:利用计算机辅助新药设计(Computer Aided Drug Design,CADD)技术中的受体图像法,对不同类型降血脂药物的化学结构及甘草次酸类的降血脂药效结构进行模型化研究,并初步探讨甘草次酸类的降血脂药理作用机制。方法:利用计算机程序EMO(分子力学程序)和GEOMOS(量子力学)以及Semi-empirical PM3方法,对4种不同类型的32个具有降血脂活性的分子进行分析。通过分子能量的降低和空间结构的优化处理,测定和计算这些分子的有关几何性、电性和能量参数。然后对优化后分子进行类型内重叠和有关参数的类型间对比观察,预测各类分子的共同药效结构和功能基团。分子重叠的可行性用参数RMS(Root Meam Square)进行判断。结果:分别获得32个降血脂活性分子的4种不同特征的药效基本结构图像,并发现甘草酸类(如18β-甘草次酸)与苯氧乙酸类(fibrates)分子的优化空间构型中,存在类似的特定结构片段,相应原子和原子团的电荷密度分布(net charges)、3个电荷中心分布及其相间距离具有可观的相似性。说明在甘草酸类的优化空间结构上可能具有与苯氧乙酸类药物类似的药效结构片段存在,甘草次酸及18-脱氢甘草次酸的铵盐降低71%的甘油三酯和51%胆固醇浓度。结论:甘草次酸类可能具有与苯氧乙酸类类似的降血脂作用机理,同时与苯氧乙酸类的作用特点类似。  相似文献   
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目的人们对膳食模式、代谢紊乱与左心室功能的关系研究报道不多,本研究旨在探讨膳食模式和左心室功能之间的关系以及代谢紊乱与动脉粥样硬化的关系。方法膳食模式采用降秩回归(reduced rankregression,RRR)方法构建;左室重量、心搏量和左室射血分数采用磁共振成像测量;膳食模式和左室指数之间的关系采用横断面分析法。结果选用4601例45~84岁、无临床心血管疾病受试者,RRR膳食模式得分数与高血糖指数、高脂肉类、奶酪、加工食品的摄人量呈正相关,而与蔬菜、大豆、水果、绿茶、黑茶、低脂甜点、种子、坚果和鱼肉的低摄入量呈负相关。多变量分析显示,RRR膳食模式得分增加1个单位,左室重量/体表面积就增加0.32g/ ㎡,心博量减少0.43mL/㎡,左室射血分数则减少0.21%。调整代谢综合征组分后,RRR膳食模式得分与左室重量和心搏指数之间的相关性减低,变为差异有统计学意义(P%0.05)。结论RRR膳食模式、代谢紊乱与左室功能紊乱有关。本研究属于横断面研究,结果的可靠性有待前瞻性研究进一步证实。  相似文献   
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