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排序方式: 共有6815条查询结果,搜索用时 15 毫秒
71.
Jose R. Gonzalez‐Porras Fernando Escalante Emilia Pardal Magdalena Sierra Luis J. Garcia‐Frade Santiago Redondo Maryam Arefi Carlos Aguilar Fernando Ortega Erik de Cabo Rosa M. Fisac Oscar Sanz Carmen Esteban Ignacio Alberca Mercedes Sanchez‐Barba Maria T. Santos Abel Fernandez Tomas J. Gonzalez‐Lopez representing the Grupo de Trombosis y Hemostasia de Castilla y León 《European journal of haematology》2013,91(3):236-241
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Krzysztof Szwed Wojciech Pawliszak Magdalena Szwed Marta Tomaszewska Lech Anisimowicz Alina Borkowska 《The Journal of thoracic and cardiovascular surgery》2021,161(4):1275-1282.e4
BackgroundNeuropsychiatric complications of surgical coronary revascularization are inconspicuous but frequent and clinically relevant. So far, attempts to reduce their occurrence, such as the introduction of off-pump coronary artery bypass (OPCAB) grafting method, have not brought the desired results. The aim of this trial was to determine whether using any of the 2 selected modifications of OPCAB could decrease the incidence of these undesired sequelae.MethodsIn this single-center, assessor- and patient-blinded, superiority, randomized controlled trial, 192 patients scheduled for elective isolated OPCAB were randomized to 3 parallel arms. The control arm underwent “conventional” OPCAB with vein grafts. The first study arm underwent anaortic OPCAB (ANA) with total arterial revascularization. The second study arm underwent OPCAB with vein grafts using carbon dioxide surgical field flooding (CO2FF). Outcomes included the incidence of postoperative delirium (PD) and early postoperative cognitive dysfunction (ePOCD).ResultsThe incidence of PD was 35.9% in the control (OPCAB) arm, 32.8% in the CO2FF arm, and 12.5% in the ANA arm (χ2 [2, N = 191] = 10.17; P = .006). Post hoc tests revealed that the incidence of PD in the ANA arm differed from that in the OPCAB arm (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.09-0.68; P = .002). The incidence of ePOCD was 34.4% in the OPCAB arm, 28.1% in the CO2FF arm, and 9.5% in the ANA arm (χ2 [2, N = 191] = 11.58; P = .003). Post hoc tests revealed that the incidence of ePOCD differed between the ANA and OPCAB arms (OR, 0.20; 95% CI, 0.06-0.58; P < .001).ConclusionsPerforming ANA significantly decreases the incidence of PD and ePOCD compared with “conventional” OPCAB with vein grafts, whereas CO2FF is inconsequential in this regard. These results, which probably reflect decreased delivery of embolic load to the brain in ANA, may have practical applicability in daily practice to improve clinical outcomes. 相似文献
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Meike Stumpp Marian Y. Hu Frank Melzner Magdalena A. Gutowska Narimane Dorey Nina Himmerkus Wiebke C. Holtmann Sam T. Dupont Michael C. Thorndyke Markus Bleich 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(44):18192-18197
Calcifying echinoid larvae respond to changes in seawater carbonate chemistry with reduced growth and developmental delay. To date, no information exists on how ocean acidification acts on pH homeostasis in echinoderm larvae. Understanding acid–base regulatory capacities is important because intracellular formation and maintenance of the calcium carbonate skeleton is dependent on pH homeostasis. Using H+-selective microelectrodes and the pH-sensitive fluorescent dye BCECF, we conducted in vivo measurements of extracellular and intracellular pH (pHe and pHi) in echinoderm larvae. We exposed pluteus larvae to a range of seawater CO2 conditions and demonstrated that the extracellular compartment surrounding the calcifying primary mesenchyme cells (PMCs) conforms to the surrounding seawater with respect to pH during exposure to elevated seawater pCO2. Using FITC dextran conjugates, we demonstrate that sea urchin larvae have a leaky integument. PMCs and spicules are therefore directly exposed to strong changes in pHe whenever seawater pH changes. However, measurements of pHi demonstrated that PMCs are able to fully compensate an induced intracellular acidosis. This was highly dependent on Na+ and HCO3−, suggesting a bicarbonate buffer mechanism involving secondary active Na+-dependent membrane transport proteins. We suggest that, under ocean acidification, maintained pHi enables calcification to proceed despite decreased pHe. However, this probably causes enhanced costs. Increased costs for calcification or cellular homeostasis can be one of the main factors leading to modifications in energy partitioning, which then impacts growth and, ultimately, results in increased mortality of echinoid larvae during the pelagic life stage. 相似文献
76.
Venkatesh Pilla Reddy Magdalena Kozielska Rik de Greef An Vermeulen Johannes H. Proost 《Journal of pharmacokinetics and pharmacodynamics》2013,40(3):377-388
High and variable placebo effect (PE) within and among clinical trials can substantially affect conclusions about the efficacy of new drugs in the treatment of schizophrenia and other neuropsychiatric disorders. In recent years, it has become increasingly difficult to prove drug efficacy against placebo, and one of the reasons is that the placebo response has increased over recent years. The increased placebo response over the years is partly explained by unidentified parallel interventions, patient factors, issues with trial designs, and regional variability or demographic differences. In addition, a nocebo effect, which is undesirable effects a subject manifests after receiving placebo, e.g. extrapyramidal side effects, in placebo arms of antipsychotic trials could also influence the PE and clinical trial outcomes. Placebo effects (PEs) are a natural phenomenon and cannot be avoided completely in clinical trials. However, accounting for the PE via mixed effects modelling approaches could reduce bias in quantifying the overall effect size of the drug treatment. This review article focuses on the PE and its impact on schizophrenia clinical trial outcomes. The authors briefly describe the factors that lead to high and variable PE. Next, pharmacometric approaches to account for the PE and dropouts in schizophrenia clinical trials are described. Finally, some points are provided that could be considered while designing and optimizing antipsychotic trials via simulation approaches. 相似文献
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Magdalena Groblewska Barbara Mroczko Mariusz Gryko Anna Pryczynicz Katarzyna Guzińska-Ustymowicz Bogusław Kędra Andrzej Kemona Maciej Szmitkowski 《Tumour biology》2014,35(4):3793-3802
The objective of the study was the assessment of serum levels and tissue expression of matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of matrix metalloproteinases 2 (TIMP-2) in patients with colorectal cancer (CRC). The study included 72 CRC patients and 68 healthy subjects. The serum levels of MMP-2 and TIMP-2 were measured using enzyme-linked immunosorbent assay (ELISA) method, whereas tissue expression of MMP-2 and TIMP-2 in cancer cells, interstitial inflammatory cells, and adjacent normal colorectal mucosa were examined by immunohistochemical staining of tumor samples. The serum levels of MMP-2 and TIMP-2 in cancer patients were significantly lower than those in control group, but the percentage of positive immunoreactivity of these proteins were higher in malignant and inflammatory cells as compared to normal tissue. There was a significant correlation between MMP-2 immunoreactivity in inflammatory cells and the presence of distant metastases and between TIMP-2 expression in inflammatory cells and tumor size, nodal involvement, and distant metastases. Area under receiver operating characteristic (ROC) curve (AUC) for serum MMP-2 was higher than for serum TIMP-2. Moreover, positive tissue expression of MMP-2 was a significant prognostic factor for CRC patients’ survival. Our findings suggest that MMP-2 and TIMP-2 might play a role in the process of colorectal cancer invasion and metastasis, but the significance of their interactions with tumor stroma and interstitial inflammatory infiltration in colorectal neoplasia require further elucidation. 相似文献
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