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排序方式: 共有4510条查询结果,搜索用时 15 毫秒
81.
Antonio Bayés de Luna MD PhD Wojciech Zareba MD PhD Miquel Fiol MD PhD Kjell Nikus MD PhD Yochai Birnbaum MD PhD Rafael Baranowski MD PhD Diego Goldwasser MD Paul Kligfield MD PhD Ryszard Piotrowicz MD PhD Günter Breithardt MD PhD Hein Wellens MD PhD 《Annals of noninvasive electrocardiology》2014,19(5):426-441
82.
Yochai Birnbaum Miguel Fiol Kjell Nikus Javier Garcia Niebla Ljuba Bacharova Sergio Dubner Wojciech Zareba Peter W. Macfarlane Antonio Luiz Ribeiro Iwona Cygankiewicz Antoni Bayes de Luna 《Annals of noninvasive electrocardiology》2020,25(5)
The Fourth Universal Definition of Myocardial Infarction (FUDMI) focuses on the distinction between nonischemic myocardial injury and myocardial infarction (MI), along with the role of cardiovascular magnetic resonance, in order to define the etiology of myocardial injury. As a consequence, there is less emphasis on updating the parts of the definition concerning the electrocardiographic (ECG) changes related to MI. Evidence of myocardial ischemia is a prerequisite for the diagnosis of MI, and the ECG is the main available tool for (a) detecting acute ischemia, (b) triage, and (c) risk stratification upon presentation. This review focuses on multiple aspects of ECG interpretation that we firmly believe should be considered for incorporation in any future update to the Universal Definition of MI. 相似文献
83.
Agnieszka Nielepkowicz-Goździńska Wojciech Fendler Ewa Robak Lilianna Kulczycka-Siennicka Paweł Górski Tadeusz Pietras Ewa Brzeziańska Adam Antczak 《Archivum immunologiae et therapiae experimentalis》2014,62(3):231-238
The purpose of this study is to evaluate the relationship between the concentration of interleukin-8 (IL-8) in exhaled breath condensate (EBC) and bronchoalveolar lavage fluid (BALF) with the disease activity score and pulmonary function of systemic lupus erythematosus (SLE) patients with and without pulmonary fibrosis. Thirty-four SLE patients and 31 healthy controls were enrolled and evaluated using high-resolution computed tomography (HRCT), pulmonary function tests, systemic lupus activity measure (SLAM), assessing BALF and EBC. IL-8 levels in BALF and EBC samples were measured with an enzyme-immunosorbent assay kit. The mean (±SEM) IL-8 concentrations in BALF and EBC were higher in SLE patients compared to healthy controls (34.84 ± 95.0 vs. 7.65 ± 21.22 pg/ml, p < 0.001; 3.82 ± 0.52 pg/m vs. 1.7 ± 1.7 pg/ml, p < 0.001, respectively). SLE patients had increased percentage of neutrophils in BALF when compared with control group (1.00 ± 5.99 vs. 0.00 ± 0.56 %, p = 0.0003). Pulmonary fibrosis in HRCT was found in 50 % of SLE patients. The disease activity scored by SLAM was significantly higher and total lung capacity was significantly lower in SLE patients with pulmonary fibrosis (8.00 ± 3.17 vs. 6.00 ± 2.31, p = 0.01; 88.00 ± 28.29 vs. 112.00 ± 21.08 % predicted, p = 0.01, respectively). In SLE patients with pulmonary fibrosis, correlations were found between SLAM and IL-8 concentration in BALF, forced expiratory volume in 1 s and forced vital capacity (r = 0.65, p = 0.006; r = ?0.53, p = 0.035; r = ?0.67, p = 0.006, respectively). Our results indicate that IL-8 plays an important role in the pathogenesis of SLE. An increased concentration of IL-8 according to BALF could be considered as a useful biomarker of SLE activity and pulmonary fibrosis in SLE. 相似文献
84.
Kai Liu Dong Chen Alessio Marcozzi Lifei Zheng Juanjuan Su Diego Pesce Wojciech Zajaczkowski Anke Kolbe Wojciech Pisula Klaus Müllen Noel A. Clark Andreas Herrmann 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(52):18596-18600
Complexation of biomacromolecules (e.g., nucleic acids, proteins, or viruses) with surfactants containing flexible alkyl tails, followed by dehydration, is shown to be a simple generic method for the production of thermotropic liquid crystals. The anhydrous smectic phases that result exhibit biomacromolecular sublayers intercalated between aliphatic hydrocarbon sublayers at or near room temperature. Both this and low transition temperatures to other phases enable the study and application of thermotropic liquid crystal phase behavior without thermal degradation of the biomolecular components.Liquid crystals (LCs) play an important role in biology because their essential characteristic, the combination of order and mobility, is a basic requirement for self-organization and structure formation in living systems (1–3). Thus, it is not surprising that the study of LCs emerged as a scientific discipline in part from biology and from the study of myelin figures, lipids, and cell membranes (4). These and the LC phases formed from many other biomolecules, including nucleic acids (5, 6), proteins (7, 8), and viruses (9, 10), are classified as lyotropic, the general term applied to LC structures formed in water and stabilized by the distinctly biological theme of amphiphilic partitioning of hydrophilic and hydrophobic molecular components into separate domains. However, the principal thrust and achievement of the study of LCs has been in the science and application of thermotropic materials, structures, and phases in which molecules that are only weakly amphiphilic exhibit LC ordering by virtue of their steric molecular shape, flexibility, and/or weak intermolecular interactions [e.g., van der Waals and dipolar forces (11)]. These characteristics enable thermotropic LCs (TLCs) to adopt a wide variety of exotic phases and to exhibit dramatic and useful responses to external forces, including, for example, the electro-optic effects that have led to LC displays and the portable computing revolution. This general distinction between lyotropic LCs and TLCs suggests there may be interesting possibilities in the development of biomolecular or bioinspired LC systems in which the importance of amphiphilicity is reduced and the LC phases obtained are more thermotropic in nature. Such biological TLC materials are very appealing for several reasons. Most biomacromolecules were extensively characterized in aqueous environments, but in TLC phases, their solvent-free properties and functions could be investigated in a state in which no or only traces of water are present. Water exhibits a high dielectric constant and has the ability to form hydrogen bonds, greatly influencing the structure and functions of biomacromolecules or compromising electronic properties such as charge transport (12–15). Indeed, anhydrous TLC systems containing glycolipids (16–19), ferritin (20), and polylysine have been reported (21–23). However, a general approach to fabricating TLCs based on nucleic acids, polypeptides, proteins, and protein assemblies of large molecular weights such as virus particles remains elusive.Here we propose that the combination of biomaterials with suitably chosen surfactants, followed by dehydration, can be effectively applied as a simple generic scheme for producing biomacromolecular-based TLCs. We demonstrate that biological TLCs can be made from a remarkable range of biomolecules and bio-inspired molecules, including nucleic acids, polypeptides, fusion proteins, and viruses. TLC materials typically combine rigid or semirigid anisometric units, which introduce orientational anisotropy, with flexible alkyl chains, which suppress crystallization (24). In the present experiments, negatively charged biomolecules and bio-inspired molecules act as rigid parts, and cationic surfactants make up the flexible units to produce TLC phases with remarkably low LC-isotropic clearing temperatures, which is another TLC signature. Electrostatic interactions couple these rigid and flexible components into hybrid assemblies, which then order into lamellar phases of alternating rigid and flexible layers (Fig. 1) stabilized by the tendency in TLCs for rigid and flexible to spatially segregate (25).Open in a separate windowFig. 1.Proposed structures of TLCs formed by the biological building blocks complexed with surfactants, showing sketches of various lamellar phases and the corresponding phase transition temperatures (°C). The lamellar bilayer structures are made of, alternately, a sublayer of the biomacromolecules and an interdigitated sublayer of the surfactants, where the negatively charged parts of the biomolecules (e.g., phosphate groups of ssDNA and ssRNA, glutamate residues of supercharged ELPs, and N-terminal glutamate and aspartate residues of pVIII protein in phages) electrostatically interact with the cationic head groups of the surfactants. For the ssDNA–DOAB and ssRNA–DOAB smectic TLCs, the oligonucleotides are randomly orientated in the DNA (RNA) sublayers. For the ELP–DDAB complexes, in addition to the bilayer smectic phase, a modulated smectic (Smmod) phase is observed at lower temperature. For the phage–DOAB–DDAB lamellar structures, rodlike virus particles are embedded in a sublayer between interdigitated surfactants with additional in-plane orientational order. 相似文献
85.
Michał Kowalczyk Małgorzata Guz Estera Okoń Witold Jeleniewicz Luiza Grzycka-Kowalczyk Michał Kiełbus Jarosław Dudka Wojciech Suseł Wojciech Dąbrowski Andrzej Stepulak 《Pharmacological reports : PR》2019,71(3):528-534
BackgroundThere is debate regarding whether inhaled sevoflurane or intravenous propofol used during anesthesia achieves the best outcome. Propofol has been shown to affect expression of matrix metalloproteinases (MMPs). MMPs are enzymes that play a role in extracellular matrix remodeling, with activity balance disturbances during surgery. The goal of this study was to compare MMP-2/9 concentrations, activity, and tissue inhibitors of metalloproteinases (TIMPs) 1/2 concentrations in blood of who had undergone 2 types of anesthesia: based on volatile sevoflurane and intravenous propofol during non-oncological, non-vascular surgery.Methods39 patients were enrolled into analysis, 20 anesthetized with total intravenous anesthesia with propofol (P), 19 with volatile induction/maintenance of anesthesia with sevoflurane (S). Plasma samples collected before and 24 h after surgery were analyzed for MMP-2/9, and TIMP-1/2 concentrations using ELISAs. Additionally, MMP-2/9 activities were assessed by gelatin zymography.ResultsStudy revealed increased MMP-9 concentration (ELISA) (P:p = 0.011; S:p = 0.001) and activity (zymography) (P:p = 0.004; S:p = 0.008) in both groups 24 h after surgery. We noticed decreased (both groups) MMP-2 concentration (P:p = 0.044; S:p = 0.027) with MMP-2 activity increase (P:p = 0.002; S:p = 0.006) 24 h after surgery. We observed decreased TIMP-1 plasma concentrations (P:p = 0.002; S:p = 0.000) 24 h after procedures, while TIMP-2 plasma levels remain unchanged (P:p = 0.097; S:p = 0.172). There were no differences between concentration and activity of MMPs and TIMPs in regard to anesthetic used. Meperidine administration correlated with lower MMP-9 activity (R=-0.430; p = 0.006).ConclusionsConcluding, neither sevoflurane nor propofol used as anesthetics modulate MMP-2 and MMP-9 concentrations and activities during non-oncological, non-vascular elective surgery. Meperidine seems to decrease MMP-9 activity. 相似文献
86.
87.
Hrynkiewicz-Szymańska A Kuch M Demkow M Barczewska M Braksator W Konka M Dłużniewski M 《Kardiologia polska》2012,70(1):55-57
Patent foramen ovale (PFO) is the most common cause of right-to-left shunt which carries a significant risk for stroke when associated with venous thrombosis, coagulation abnormalities or other conditions. We present a young male in whom diving was associated with stroke in a subject with otherwise clinically silent PFO. 相似文献
88.
We present the case of a 60 year-old woman with a stage III fallopian tube cancer submitted to hysterectomy and bilateral salpingo-oophorectomy with partial omenectomy, followed by six courses of chemotherapy and revision surgery. After each course of chemotherapy (paclitaxel + carboplatin) preceded by premedication with dexamethasone, she suffered from side- -effects, of which the most unpleasant was severe dizziness appearing on the third, fourth and fifth day following the listed combination of drugs. It was revealed that dizziness with concomitant sweating and rapid pulse, noted in the standing position, was combined with marked postural hypotension. Considering the possibility of a temporary pituitary-adrenal axis suppression caused by premedication with a very large dose of dexamethasone, during those three days she was supplemented with small doses of hydrocortisone, which caused almost complete disappearance of the mentioned symptoms. Our conclusion is that postural hypotension causing severe dizziness initially linked with chemotherapeutic drugs can be eliminated or markedly reduced by three days supplementation with hydrocortisone applied after the expected wash out of the dexamethasone. 相似文献
89.
90.