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排序方式: 共有537条查询结果,搜索用时 15 毫秒
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The constitutional gain-of-function variant p.Glu1099Lys in NSD2 is associated with a novel syndrome
Bernt Popp Melanie Brugger Sibylle Poschmann Tobias Bartolomaeus Maximilian Radtke Julia Hentschel Nataliya Di Donato Andreas Rump Janina Gburek-Augustat Elisabeth Graf Matias Wagner Ina Sorge Johannes R Lemke Thomas Meitinger Rami Abou Jamra Vincent Strehlow Theresa Brunet 《Clinical genetics》2023,103(2):226-230
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Background
Phosphoinositides mediate one of the intracellular signal transduction pathways and produce a class of second messengers that are involved in the action of hormones and neurotransmitters on target cells. Thyroid hormones are well known regulators of lipid metabolism and modulators of signal transduction in cells. However, little is known about phosphoinositides cycle regulation by thyroid hormones. The present paper deals with phosphoinositides synthesis de novo and acylation in liver at different thyroid status of rats. 相似文献4.
Silicon carbide nanotubes (SiCNTs) have generated significant research interest due to their potential use in the fabrication of electronic and optoelectronic nanodevices and biosensors. The exceptional chemical, electrical and thermal properties of SiCNTs are beneficial for their application in high-temperature and harsh-environments. In view of the limited thermal stability of carbon nanotubes, they can be replaced by silicon carbide nanotubes in reinforced composites, developed for operations at high temperatures. However, fundamentally theoretical studies of the mechanical properties of the silicon carbide nanotubes are at an early stage and their results are still insufficient for designing and exploiting appropriate nanodevices based on SiCNTs and reinforced composites. In this context, the present study deals with the determination of Young’s and shear moduli of non-chiral single-walled silicon carbide nanotubes, using a three-dimensional finite element model. 相似文献
5.
Brian Walls Oisín Murtagh Sergey I. Bozhko Andrei Ionov Andrey A. Mazilkin Daragh Mullarkey Ainur Zhussupbekova Dmitry A. Shulyatev Kuanysh Zhussupbekov Nikolai Andreev Nataliya Tabachkova Igor V. Shvets 《Materials》2022,15(21)
The strongly correlated electron material, vanadium dioxide (VO), has seen considerable attention and research application in metal-oxide electronics due to its metal-to-insulator transition close to room temperature. Vacuum annealing a VO(010) single crystal results in Wadsley phases (VO, n > 1) and VO. The resistance changes by a factor of 20 at 342 K, corresponding to the metal-to-insulator phase transition of VO. Macroscopic voltage-current measurements with a probe separation on the millimetre scale result in Joule heating-induced resistive switching at extremely low voltages of under a volt. This can reduce the hysteresis and facilitate low temperature operation of VO devices, of potential benefit for switching speed and device stability. This is correlated to the low resistance of the system at temperatures below the transition. High-resolution transmission electron microscopy measurements reveal a complex structural relationship between VO, VO and VO crystallites. Percolation paths incorporating both VO and metallic VO are revealed, which can reduce the resistance below the transition and result in exceptionally low voltage resistive switching. 相似文献
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Roman Vasiliev Darya Kurtina Nataliya Udalova Vadim Platonov Abulkosim Nasriddinov Tatyana Shatalova Roman Novotortsev Xiaogan Li Marina Rumyantseva 《Materials》2022,15(22)
Two-dimensional nanosheets of semiconductor metal oxides are considered as promising for use in gas sensors, because of the combination of a large surface-area, high thermal stability and high sensitivity, due to the chemisorption mechanism of gas detection. In this work, 2D SnO2 nanosheets were synthesized via the oxidation of template SnS2 nanosheets obtained by surfactant-assisted one-pot solution synthesis. The 2D SnO2 was characterized using transmission and scanning electron microscopy (TEM, SEM), X-ray diffraction (XRD), low-temperature nitrogen adsorption, X-ray photoelectron spectroscopy (XPS) and IR spectroscopy. The sensor characteristics were studied when detecting model gases CO and NH3 in dry (RH25 = 0%) and humid (RH25 = 30%) air. The combination of high specific-surface-area and increased surface acidity caused by the presence of residual sulfate anions provides a high 2D SnO2 sensor’s signal towards NH3 at a low temperature of 200 °C in dry air, but at the same time causes an inversion of the sensor response when detecting NH3 in a humid atmosphere. To reveal the processes responsible for sensor-response inversion, the interaction of 2D SnO2 with ammonia was investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) in dry and humid air at temperatures corresponding to the maximum “positive” and maximum “negative” sensor response. 相似文献
7.
Yuriy Y Kulyabin Alexey V Voitov Nataliya R Nichay Ilya A Soynov Alexey V Zubritskiy Alexander V Bogachev-Prokophiev 《Interactive Cardiovascular and Thoracic Surgery》2022,35(2)
Open in a separate window OBJECTIVESThe appropriate approach for surgical repair of coarctation of the aorta with a ventricular septal defect (VSD) remains controversial. This study evaluated the outcomes of primary repair of VSDs with periventricular device closure without cardiopulmonary bypass through a left thoracotomy in patients without arch hypoplasia.METHODSWe selected 21 patients aged <1 year, including 7 neonates, who underwent repair of coarctation of the aorta with periventricular device closure of a VSD.RESULTSThe median occluder size was 6 (range, 5–8) mm. The median mechanical ventilation time was 14 (range, 2–68) h, and the median duration of hospital stay was 11 (range, 7–16) days. No reoperations were required to correct VSD shunting, and the median residual shunt size was 1 (range, 1–2) mm. The median follow-up period was 13 (range, 4–31) months. No late deaths were reported, and no haemodynamically significant pressure gradient at the anastomotic site was observed. The median distal aortic arch z-score was 0.39 (range, −0.1–to 0.9). Only 1 patient had a permanent pacemaker implanted towards the end of the follow-up period.CONCLUSIONSPeriventricular device closure can be used safely for closure of VSD in children with coarctation of the aorta without a hypoplastic aortic arch, even in neonates, to reduce the risk of prolonged cardiopulmonary bypass. This hybrid approach can be performed with a low incidence of rhythm disturbances and residual shunting. However, a meticulous assessment of the VSD anatomy is essential to avoid any unfavourable events. 相似文献
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9.
We report a case of acquired thrombotic thrombocytopenic purpura (TTP) in a 34-year old patient with a prior diagnosis of
systemic lupus erythematosis (SLE) who was recently started on hydroxychloroquine. Presenting symptoms included fevers, sore
throat and productive cough with progressive weakness, dyspnea on exertion, hemoptysis and dark urine. Initial laboratory
abnormalities were consistent with an acute microangiopathic hemolytic anemia and severe thrombocytopenia. At the time of
admission, the patient’s lupus was highly active as evident by his high SLE Disease Activity Index (SLEDAI) score. He was
later also found to have severely reduced ADAMTS-13 levels and a positive antibody assay. This case highlights the occasional
difficulty in pinpointing the exact etiology of TTP as well as establishes a possible novel drug association between hydroxychloroquine
and TTP development. 相似文献
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