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排序方式: 共有234条查询结果,搜索用时 15 毫秒
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Repeated endotracheal intubation is associated with complications and additional risks for a preterm infant. The aim of this study was to determine the risk factors related to extubation failure (EF) in preterm newborns.
Materials and methods
Ninety two very preterm infants with respiratory distress syndrome (RDS), birth weight of <1500 g, mechanically ventilated, and extubated before the 7th day of life were enrolled into prospective study. Following extubation, noninvasive respiratory support was provided. Infants who required reintubation within 72 h after primary extubation constituted the main group (n = 27) while those, whose primary extubation was successful, were included into the comparison group (n = 65).Results
Infants from the main group differed by lower antenatal steroid administration rate, higher incidence of intraventricular hemorrhage, severe RDS, arterial hypotension, metabolic acidosis, and pulmonary bleeding, as well as by the need in higher initial mechanical ventilation settings. According to logistic regression analysis the risk of EF was significantly associated with severe RDS (OR – 3.82; 95% CI: 1.21–12.02), arterial hypotension (OR – 24.05; 95% CI: 1.99–290.48) or metabolic acidosis (OR – 4.62; 95% CI: 1.41–15.16) in the first 3 days of life. Antenatal steroid prophylaxis considerably decreased the probability of EF (OR – 0.2; 95% CI: 0.063–0.68).Conclusions
The risk of reintubation after primary extubation is determined by severe RDS, arterial hypotension or metabolic acidosis during the first 3 days of life. Antenatal steroid prophylaxis substantially decreases this risk. The method of non-invasive respiratory support following primary extubation does not influence the reintubation risk. 相似文献35.
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Aleksandra Przewoka Serguei Smirnov Irina Nefedova Aleksandra Krajewska Igor S. Nefedov Petr S. Demchenko Dmitry V. Zykov Valentin S. Chebotarev Dmytro B. But Kamil Stelmaszczyk Maksym Dub Dariusz Zasada Alvydas Lisauskas Joachim Oberhammer Mikhail K. Khodzitsky Wojciech Knap Dmitri Lioubtchenko 《Materials》2021,14(23)
Thin layers of silver nanowires are commonly studied for transparent electronics. However, reports of their terahertz (THz) properties are scarce. Here, we present the electrical and optical properties of thin silver nanowire layers with increasing densities at THz frequencies. We demonstrate that the absorbance, transmittance and reflectance of the metal nanowire layers in the frequency range of 0.2 THz to 1.3 THz is non-monotonic and depends on the nanowire dimensions and filling factor. We also present and validate a theoretical approach describing well the experimental results and allowing the fitting of the THz response of the nanowire layers by a Drude–Smith model of conductivity. Our results pave the way toward the application of silver nanowires as a prospective material for transparent and conductive coatings, and printable antennas operating in the terahertz range—significant for future wireless communication devices. 相似文献
37.
Maksim Storozhuk Andrii Cherninskyi Oleksandr Maximyuk Dmytro Isaev Oleg Krishtal 《Current Neuropharmacology》2021,19(9):1570
Acid-sensing ion channels (ASICs) are Na+-permeable ion channels activated by protons and predominantly expressed in the nervous system. ASICs act as pH sensors leading to neuronal excitation. At least eight different ASIC subunits (including ASIC1a, ASIC1b, ASIC2a, ASIC2b, ASIC3, ASIC4, ASIC5) are encoded by five genes (ASIC1-ASIC5). Functional ASICs assembled in the plasma membrane are homo- or heteromeric trimers. ASIC1a-containing trimers are of particular interest as, in addition to sodium ions, they also conduct calcium ions and thus can trigger or regulate multiple cellular processes. ASICs are widely but differentially expressed in the central and peripheral nervous systems. In the mammalian brain, a majority of neurons express at least one ASIC subunit. Several recent reviews have summarized findings of the role of ASICs in the peripheral nervous system, particularly in nociception and proprioception, and the structure-function relationship of ASICs. However, there is little coverage on recent findings regarding the role of ASICs in the brain. Here we review and discuss evidence regarding the roles of ASICs: (i) as postsynaptic receptors activated by protons co-released with glutamate at glutamatergic synapses; (ii) as modulators of synaptic transmission at glutamatergic synapses and GABAergic synapses; (iii) in synaptic plasticity, memory and learning; (iv) in some pathologies such as epilepsy, mood disorders and Alzheimer''s disease. 相似文献
38.
Renata yszczek Iwona Rusinek Agnieszka Ostasz Justyna Sienkiewicz-Gromiuk Dmytro Vlasyuk Marcin Groszek Agnieszka Lipke Oleksiy Pavlyuk 《Materials》2021,14(17)
Solvothermal reactions of lanthanide (III) salts with 1,2-phenylenediacetic acid in N,N′-dimethylformamide (DMF) solvent lead to the formation of the metal complexes of the general formula Ln2(1,2-pda)3(DMF)2, where Ln(III) = Pr(1), Sm(2), Eu(3), Tb(4), Dy(5), and Er(6), 1,2-pda = [C6H4(CH2COO)2]2−. The compounds were characterized by elemental analysis, powder and single-crystal X-ray diffraction methods, thermal analysis methods (TG-DSC and TG-FTIR), infrared and luminescence spectroscopy. They exhibit structural similarity in the two groups (Pr, Sm, and Eu; Tb, Dy, and Er), which was reflected in their thermal behaviours and spectroscopic properties. Single-crystal X-ray diffraction studies reveal that Sm(2) and Eu(3) complexes form 2D coordination polymers with four crystallographically independent metal centers. Every second lanthanide ion is additionally coordinated by two DMF molecules. The 1,2-phenylenediacetate linker shows different denticity being: penta- and hexadentate while carboxylate groups exhibit bidentate-bridging, bidentate-chelating, and three-dentate bridging-chelating modes. The infrared spectra reflect divergence between these two groups of complexes. The complexes of lighter lanthanides contain in the structure coordinated DMF molecules, while in the structures of heavier complexes, DMF molecules appear in the inner and outer coordination sphere. Both carboxylate groups are deprotonated and engaged in the coordination of metal centers but in different ways in such groups of complexes. In the groups, the thermal decomposition of the isostructural complexes occurs similarly. Pyrolysis of complexes takes place with the formation of such gaseous products as DMF, carbon oxides, ortho-xylene, ethers, water, carboxylic acids, and esters. The complexes of Eu and Tb exhibit characteristic luminescence in the VIS region, while the erbium complex emits NIR wavelength. 相似文献
39.
Oz M Isaev D Lorke DE Hasan M Petroianu G Shippenberg TS 《British journal of pharmacology》2012,166(1):168-176