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61.
Digit ratio (2D:4D) does not correlate with daily 17β‐estradiol and progesterone concentrations in healthy women of reproductive age 下载免费PDF全文
62.
Tomasz Cytlak Monika Skibiska Patrycja Kaczmarek Marcin Ka
mierczak Magdalena Rapp Maciej Kubicki Henryk Koroniak 《RSC advances》2018,8(22):11957
Direct conversion of the α-hydroxyl group by para-toluenesulfonamide to yield α-(N-tosyl)aminophosphonates is reported. α-Aminophosphonates 23a,b–37a,b were obtained from the corresponding α-hydroxyphosphonates 6a,b–21a,b in the presence of K2CO3, via the retro-Abramov reaction of the appropriate aldehydes, 1–5. The subsequent formation of imines with simultaneous addition of diethyl phosphite provided access to the α-sulfonamide phosphonates 23a,b–37a,b with better diastereoselectivity than in the case of the Pudovik reaction. The mechanism for this transformation is proposed herein. When Cbz N-protected aziridine 9a,b and phenylalanine analogue 12a,b were exploited, intramolecular substitution was observed, leading to the corresponding epoxide 38 as the sole product, or oxazolidin-2-one 39 as a minor product. Analogous substitution was not observed in the case of proline 18a,b and serine 21a,b derivatives.The reaction mechanism and diastereoselectivity of the direct transformation of α-hydroxyphosphonates 6a,b–21a,b by para-toluenesulfonamide, yielding α-(N-tosyl)aminophosphonates 23a,b–37a,b under K2CO3 conditions are presented. 相似文献
63.
Teresa Trenkwalder Anna Lena Lahmann Magdalena Nowicka Costanza Pellegrini Tobias Rheude N. Patrick Mayr Stephanie Voss Sabine Bleiziffer Rüdiger Lange Michael Joner Albert M. Kasel Adnan Kastrati Heribert Schunkert Oliver Husser Martin Hadamitzky Christian Hengstenberg 《The international journal of cardiovascular imaging》2018,34(6):985-992
Multislice computed tomography (MSCT) has emerged as the mainstay in patients planned for transcatheter aortic valve implantation (TAVI). Incidental findings (IF) in MSCT are common. However, the exact incidence, clinical relevance and further consequences of IF are unclear and it is controversial whether IF adversely affect patients’ outcome. We analyzed MSCT data of 1050 patients screened for TAVI between January 2011 and December 2014. Median follow-up of patients was 20 months. In total, 3194 IF were identified, which were classified into clinically non-relevant IF (2872, 90%) and clinically relevant IF (322, 10%). In 25% of patients (258/1050) at least one clinically relevant IF was present. Age (80?±?7 vs. 80?±?7 years; p?=?0.198) and EuroSCORE II (3.6% [2.1–5.7] vs. 3.6% [2.1–5.9]; p?=?0.874) was similar between patients with and without a clinically relevant IF. TAVI was performed less frequently in patients with a clinically relevant IF (76% vs. 85%; p?<?0.001), with more patients receiving surgical aortic valve replacement in that group (14% vs. 11%; p?=?0.042), possibly due to the high rate of incidental aneurysms of the ascending aorta (n?=?48). If TAVI was performed mortality did not differ (30-days: 4% vs. 3%; p?=?0.339, 1-year: 11% vs. 14%; p?=?0.226) between patients with and without a clinically relevant IF. Our study is the largest study to analyze prevalence, clinical relevance and therapeutic consequences of IF during screening for TAVI. IF in pre-procedural MSCT are common and clinically relevant in one-quarter of patients. However, these findings had no impact on overall mortality. 相似文献
64.
65.
Van Thiel DH George M Brems J Holt D Zhu Q Edelstein S Amiral J Tarasuk G Leone N 《The American journal of gastroenterology》2003,98(2):460-465
OBJECTIVE: The aim of this study was to determine whether liver transplantation of patients with antiphospholipid antibodies (APA) is 1) adversely affected with vascular thrombosis and 2) whether such antibodies persist post transplantation. METHODS: Twelve patients with APA awaiting transplant were identified and characterized biochemically and immunologically. Each had the level of APA determined using commercially available enzyme-linked immunoassay kits before, during, and after liver transplantation. RESULTS: No patient in this series experienced a transplant-related vascular thrombosis. The titer of APA fell to levels at or below those present in normals and remained low in two of 12 or undetectable in 10 of 12 patients 1 yr after liver transplantation. CONCLUSIONS: We reached the following conclusions: 1) Antiphospholipid positivity does not identify patients at high risk for post-transplant vascular thrombosis. 2) The levels of antiphospholipid present in sera pretransplant fell during transplantation and remained low or undetectable 1 month and 1 yr post transplantation. 相似文献
66.
Cornelia Speth Gerhard Blum Magdalena Hagleitner Caroline Hörtnagl Kristian Pfaller Beate Posch Helmut Werner Ott Reinhard Würzner Cornelia Lass-Flörl Günter Rambach 《Medical microbiology and immunology》2013,202(5):379-389
Aspergillus terreus-induced invasive infections exhibit high lethality, partly due to the intrinsic resistance for amphotericin B (AmB). We compared the virulence and pathogenesis of an AmB-resistant isolate of A. terreus (ATR) with that of a rare variant showing enhanced sensitivity for AMB (ATS). The modifications that result in enhanced AmB sensitivity of isolates are not associated with reduced virulence in vivo; instead, the ATS-infected mice died even faster than the ATR-infected animals. Since A. terreus enters the blood stream in most patients and frequently induces thrombosis, we studied a putative correlation between virulence of the two A. terreus isolates and their effect on thrombocytes. Those mice infected with the more virulent ATS isolate had lower thrombocyte numbers and more phosphatidylserine exposure on platelets than ATR-infected mice. In vitro experiments confirmed that ATS and ATR differ in their effect on thrombocytes. Conidia, aleurioconidia and hyphae of ATS were more potent than ATR to trigger thrombocyte stimulation, and thrombocytes adhered better to ATS than to ATR fungal structures. Furthermore, ATS secreted more soluble factors that triggered platelet stimulation than ATR. Thus, it might be suggested that the capacity of a fungal isolate to modulate thrombocyte parameters contributes to its virulence in vivo. 相似文献
67.
Loukia Katsouri Marcela P. Vizcaychipi Simon McArthur Ian Harrison Marc Suárez-Calvet Alberto Lleo Dafydd G. Lloyd Daqing Ma Magdalena Sastre 《Neurobiology of aging》2013
Noradrenergic deficits have been described in the hippocampus and the frontal cortex of Alzheimer's disease brains, which are secondary to locus coeruleus degeneration. Locus coeruleus is the brain stem nucleus responsible for synthesis of noradrenaline and from where all noradrenergic neurons project. In addition, it has been suggested that noradrenaline might play a role in modulating inflammatory responses in Alzheimer's disease. In this study we aimed to investigate the effect of various agonists and antagonists for adrenergic receptors on amyloid precursor protein processing. Among them, we found that prazosin, an α1-adrenoceptor antagonist, was able to reduce the generation of amyloid β in N2a cells. Treatment of transgenic APP23 mice with prazosin prevented memory deficits over time. Although prazosin did not influence amyloid plaque load, it induced astrocytic proliferation and increased the release of apolipoprotein E and anti-inflammatory cytokines. These findings suggest that chronic treatment with prazosin leads to an anti-inflammatory response with potential beneficial effects on cognitive performance. 相似文献
68.
69.
Aboma Merdasa Josefine Bunke Magdalena Naumovska John Albinsson Tobias Erlv Magnus Cinthio Nina Reistad Rafi Sheikh Malin Malmsj 《Biomedical optics express》2021,12(4):2484
Photoacoustic imaging (PAI) is a novel hybrid imaging technique that combines the advantages of optical and ultrasound imaging to produce hyperspectral images of the tissue. The feasibility of measuring oxygen saturation (sO2) with PAI has been demonstrated pre-clinically, but has limited use in humans under conditions of ischemia and reperfusion. As an important step towards making PAI clinically available, we present a study in which PAI was used to estimate the spatial distribution of sO2 in vivo during and after occlusion of the finger of eight healthy volunteers. The results were compared with a commercial oxygen saturation monitor based on diffuse reflectance spectroscopy. We here describe the capability of PAI to provide spatially resolved picture of the evolution of sO2 during ischemia following vascular occlusion of a finger, demonstrating the clinical viability of PAI as a non-invasive diagnostic tool for diseases indicated by impaired microvascularization. 相似文献
70.
Ecotoxicological characteristics and ecological risk assessment of trace elements in the bottom sediments of the Rożnów reservoir (Poland) 总被引:1,自引:0,他引:1
Szara Magdalena Baran Agnieszka Klimkowicz-Pawlas Agnieszka Tarnawski Marek 《Ecotoxicology (London, England)》2020,29(1):45-57
Ecotoxicology - The bottom sediments in catchment areas behind dams play a significant role in water ecosystems. On the other hand, the structure of sediments makes them a natural geosorbent, in... 相似文献