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排序方式: 共有5621条查询结果,搜索用时 46 毫秒
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Annemarie Weissenbacher Honglei Huang Tomas Surik Maria L. Lo Faro Rutger J. Ploeg Constantin C. Coussios Peter J. Friend Benedikt M. Kessler 《American journal of transplantation》2021,21(5):1740-1753
We describe a proteomics analysis to determine the molecular differences between normothermically perfused (normothermic machine perfusion, NMP) human kidneys with urine recirculation (URC) and urine replacement (UR). Proteins were extracted from 16 kidney biopsies with URC (n = 8 donors after brain death [DBD], n = 8 donors after circulatory death [DCD]) and three with UR (n = 2 DBD, n = 1 DCD), followed by quantitative analysis by mass spectrometry. Damage-associated molecular patterns (DAMPs) were decreased in kidney tissue after 6 hours NMP with URC, suggesting reduced inflammation. Vasoconstriction was also attenuated in kidneys with URC as angiotensinogen levels were reduced. Strikingly, kidneys became metabolically active during NMP, which could be enhanced and prolonged by URC. For instance, mitochondrial succinate dehydrogenase enzyme levels as well as carbonic anhydrase were enhanced with URC, contributing to pH stabilization. Levels of cytosolic and the mitochondrial phosphoenolpyruvate carboxykinase were elevated after 24 hours of NMP, more prevalent in DCD than DBD tissue. Key enzymes involved in glucose metabolism were also increased after 12 and 24 hours of NMP with URC, including mitochondrial malate dehydrogenase and glutamic-oxaloacetic transaminase, predominantly in DCD tissue. We conclude that NMP with URC permits prolonged preservation and revitalizes metabolism to possibly better cope with ischemia reperfusion injury in discarded kidneys. 相似文献
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Laurent Gueudré Tomas Binder Christian Chmelik Florian Hibbe Douglas M. Ruthven J?rg K?rger 《Materials》2012,5(4):721-740
Because of the small particle size, orientation-dependent diffusion measurements in microporous materials remains a challenging task. We highlight here the potential of micro-imaging by interference microscopy in a case study with MFI-type crystals in which, although with different accuracies, transient concentration profiles in all three directions can be observed. The measurements, which were performed with “rounded-boat” shaped crystals, reproduce the evolution patterns of the guest profiles recorded in previous studies with the more common “coffin-shaped” MFI crystals. The uptake and release patterns through the four principal faces (which in the coffin-shaped crystals extend in the longitudinal direction) are essentially coincident and there is no perceptible mass transfer in the direction of the long axis. The surface resistances of the four crystal faces through which mass transfer occurs are relatively small and have only a minor effect on the mass transfer rate. As a result of the pore structure, diffusion in the crystallographic c direction (which corresponds to the direction of the long axis) is expected to be much slower than in the transverse directions. This could explain the very low rate of mass transfer observed in the direction of the long axis, but it is also possible that the small end faces of the crystal may have high surface resistance. It is not possible to distinguish unequivocally between these two possibilities. All guest molecules studied (methyl-butane, benzene and 4-methyl-2-pentyne) show the same orientation dependence of mass transfer. The long 4-methyl-2-pentyne molecules would be expected to propagate at very different rates through the straight and sinusoidal channels. The coinciding patterns for uptake through the mutually perpendicular crystal faces therefore provide clear evidence that both the coffin shaped crystals and the rounded-boat-shaped crystals considered in this study, must be intergrowths rather than pure single crystals. 相似文献
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Tomas Magnusson Inger Egermark-Eriksson Gunnar E. Carlsson 《Cranio : the journal of craniomandibular practice》2013,31(4):338-344
A longitudinal study covering five years of clinical signs and subjective symptoms of mandibular dysfunction was performed in 119 adolescents, 15 years old at the first examination and 20 years old at the follow-up. Sixty-two percent had clinical signs of mandibular dysfunction, but the signs were in most cases mild, while moderate and severe signs were found in 17%. No change in clinical signs between the two examinations were noted in nearly half of the individuals, and improvement and impairment had occurred at an almost equal rate.At the follow-up, 31% of the participants reported that they sometimes had TMJ sound, tiredness in the jaws, or difficulties in mouth opening, and another 8% suffered from one or more of these symptoms frequently. The frequency of subjective symptoms as well as reports of bruxism had increased statistically significantly compared with five years previously.A statistically significant correlation was found between the subjective symptoms and the clinical dysfunction index used. No single subjective or clinical variable or combination of variables seemed to have any significant influence on the positive or negative changes of the clinical dysfunction index between the two examinations. The explanation suggested is that the development of clinical signs of mandibular dysfunction is very complex, including numerous variables, some of which were not recorded in the present investigation. 相似文献
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Early and late diastolic strain rate vs global longitudinal strain at rest and during dobutamine stress for the assessment of significant coronary artery stenosis in patients with a moderate and high probability of coronary artery disease
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Egle Rumbinaite M.D. Diana Zaliaduonyte‐Peksiene M.D. Ph.D. Tomas Lapinskas M.D. Ruta Zvirblyte M.D. Arnas Karuzas Ieva Jonauskiene Mindaugas Viezelis M.D. Indre Ceponiene M.D. Olivija Gustiene M.D. Ph.D. Rimvydas Slapikas M.D. Ph.D. Jolanta Justina Vaskelyte M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(10):1512-1522
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HIV-positive gay men may experience multiple sources of adversity and stress, related both to their HIV diagnosis and sexual identity. Most of these men, however, do not experience mental health problems. Little is known about factors that help them achieve resilience in the face of life challenges. This study examined psychosocial factors associated with resilience in a national community-based sample of 357 Australian HIV-positive gay men. Resilience was measured using the Connor–Davidson Resilience Scale. Higher levels of resilience were linked with experiencing low or no internalized HIV-related stigma, having no previous history of mental health problems, and a number of socioeconomic indicators. In addition to providing a more complete picture of the mental health of HIV-positive gay men, findings from this study can be used to inform strength-based approaches to mental health prevention and support. 相似文献