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61.
Paolo Spirito Camillo Autore Francesco Formisano Gabriele Egidy Assenza Elena Biagini Tammy S. Haas Sergio Bongioanni Christopher Semsarian Emmanuela Devoto Beatrice Musumeci Francesco Lai Laura Yeates Maria Rosa Conte Claudio Rapezzi Luca Boni Barry J. Maron 《The American journal of cardiology》2014
62.
Elena Biagini Iacopo Olivotto Maria Iascone Maria I. Parodi Francesca Girolami Giulia Frisso Camillo Autore Giuseppe Limongelli Massimiliano Cecconi Barry J. Maron Martin S. Maron Stefania Rosmini Francesco Formisano Beatrice Musumeci Franco Cecchi Attilio Iacovoni Tammy S. Haas Maria L. Bacchi Reggiani Paolo Ferrazzi Francesco Salvatore Paolo Spirito Claudio Rapezzi 《The American journal of cardiology》2014
63.
Joel L. Pederson Melissa S. Chapot Steven R. Simms Reza Sohbati Tammy M. Rittenour Andrew S. Murray Gary Cox 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(36):12986-12991
Rock art compels interest from both researchers and a broader public, inspiring many
hypotheses about its cultural origin and meaning, but it is notoriously difficult to
date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are
among the most debated examples; hypotheses about its age span the entire Holocene
epoch and previous attempts at direct radiocarbon dating have failed. We provide
multiple age constraints through the use of cross-cutting relations and new and
broadly applicable approaches in optically stimulated luminescence dating at the
Great Gallery panel, the type section of BCS art in Canyonlands National Park,
southeastern Utah. Alluvial chronostratigraphy constrains the burial and exhumation
of the alcove containing the panel, and limits are also set by our related research
dating both a rockfall that removed some figures and the rock’s exposure
duration before that time. Results provide a maximum possible age, a minimum age, and
an exposure time window for the creation of the Great Gallery panel, respectively.
The only prior hypothesis not disproven is a late Archaic origin for BCS rock art,
although our age result of A.D. ∼1–1100 coincides better with the
transition to and rise of the subsequent Fremont culture. This chronology is for the
type locality only, and variability in the age of other sites is likely.
Nevertheless, results suggest that BCS rock art represents an artistic tradition that
spanned cultures and the transition from foraging to farming in the region.Archaeology is focused upon material records, contextualized in
time. Rock art is a record with the potential to provide unique insight into the dynamics
and evolution of culture, but it generally lacks stratigraphic or chronologic context.
Interpretation of the origin and meaning of rock art is indirect at best, or simply
speculative. In the case of some pictographs, pigments may include or have enough accessory
carbon for accelerator mass spectrometry (AMS) radiocarbon dating (1–4). In other special situations, such as
caves, minimum age constraints have been obtained by various techniques of dating material
that overlies or entombs rock art (5–7). However,
most rock art remains undatable and researchers rely upon stylistic comparison and indirect
associations with artifacts at nearby sites (8, 9). The case in point for this study is arguably the
most compelling and debated rock art in the United States—the Barrier Canyon style
(BCS) of the Colorado Plateau. Previous attempts to derive an absolute chronology have
failed and its age remains unknown, with widely ranging hypotheses that have remained
untested until now.The continued development of dating techniques offers new possibilities for hypothesis
testing. The optically stimulated luminescence (OSL) signals from mineral grains make it
possible to date the deposition of most sediment that is exposed to a few seconds of full
sunlight before burial, and its use in the earth and cultural sciences has greatly
increased (10, 11). Among the latest applications of OSL are techniques dating the outer
surfaces of rock clasts that have become shielded from light, including those with
archaeological context (12–15). Recent work has furthermore used the “bleaching” profile of
decreasing luminescence signal toward the surface of rock to estimate exposure time to
sunlight (16, 17). Using these dating tools, we can constrain the age of rock art and gain new
insight into past cultures and landscapes.Here, we synthesize results from three approaches to dating the type section of BCS art,
the Great Gallery in Canyonlands National Park of southeastern Utah. Through dating the
full alluvial stratigraphy and a rockfall event that both have incontrovertible
cross-cutting relations with the rock art, and then by determining the exposure duration of
a painted rock surface, we greatly narrow the window of time when the rock art was created.
These approaches do not require direct sampling of rock art and have strong potential for
application to other archaeological and surface processes research. Although our results
are only for the type section of BCS art, and chronological variability should be expected
for the style across the region, they suggest that BCS art coincides with the transition to
agriculture in the northern Colorado Plateau and may not have been limited to a specific
archaeological culture. 相似文献
64.
Systemic lupus erythematosus (SLE) is a chronic, relapsing autoimmune connective tissue disease, primarily affecting the skin, joints, kidneys, heart, lungs, nervous system, blood elements, and serosal membranes. SLE is characterized by cytokine dysregulation, polyclonal B-cell activation, autoantibody production, and increased immune complex formation due to aberrations involving hyperactive B cells, T cells, and cells of the monocytic lineage. The symptoms of SLE are often diverse and nonspecific, and timely identification of SLE and associated comorbidities in patients is critical as aggressive monitoring and therapy may be warranted, especially in patients with poor prognoses. Based on the up-to-date understanding of the pathophysiology of SLE, the first targeted biological agent belimumab has been approved by the US Food and Drug Administration (FDA) in more than 50 years, and many targeted agents are being evaluated in late-stage clinical trials. There is a clear need to discuss how and when to incorporate new and emerging biological agents in managing patients with SLE. Additionally, the potential for increased risk of infections is a factor that heavily influences the rheumatologist?s decision to use biological agents in managing patients with SLE. Hence, in this roundtable educational activity, expert faculty will review and discuss the strategies for timely diagnosis of SLE and associated comorbidities. They will also discuss the current understanding of the pathophysiology of SLE and how new and emerging biological agents help address the underlying pathophysiological aberrations in patients with SLE. The faculty will also review strategies to minimize the risk of infections and other toxicities in patients with SLE. 相似文献
65.
Dean S. Picone Raj Padwal Norm R. C. Campbell Pierre Boutouyrie Tammy M. Brady Michael Hecht Olsen Christian Delles Cintia Lombardi Azra Mahmud Yaxing Meng Gontse G. Mokwatsi Pedro Ordunez Hoang T. Phan Giacomo Pucci Aletta E. Schutte KiChul Sung XinHua Zhang James E. Sharman for the Accuracy in Measurement of Blood Pressure Collaborative 《Journal of clinical hypertension (Greenwich, Conn.)》2020,22(12):2167
Hypertension guidelines recommend that blood pressure (BP) should be measured using a monitor that has passed validation testing for accuracy. BP monitors that have not undergone rigorous validation testing can still be cleared by regulatory authorities for marketing and sale. This is the situation for most BP monitors worldwide. Thus, consumers (patients, health professionals, procurement officers, and general public) may unwittingly purchase BP monitors that are non‐validated and more likely to be inaccurate. Without prior knowledge of these issues, it is extremely difficult for consumers to distinguish validated from non‐validated BP monitors. For the above reasons, the aim of this paper is to provide consumers guidance on how to check whether a BP monitor has been properly validated for accuracy. The process involves making an online search of listings of BP monitors that have been assessed for validation status. Only those monitors that have been properly validated are recommended for BP measurement. There are numerous different online listings of BP monitors, several are country‐specific and two are general (international) listings. Because monitors can be marketed using alternative model names in different countries, if a monitor is not found on one listing, it may be worthwhile cross‐checking with a different listing. This information is widely relevant to anyone seeking to purchase a home, clinic, or ambulatory BP monitor, including individual consumers for use personally or policy makers and those procuring monitors for use in healthcare systems, and retailers looking to stock only validated BP monitors. 相似文献
66.
67.
Michelle Berresheim Jodi Wilkie Kara A. Nerenberg Quazi Ibrahim Tammy J. Bungard 《Thrombosis research》2014
Introduction
Pregnancy is a thrombogenic state, increasing the risk for venous thromboembolism (VTE), and the risk of valve thrombosis amongst women with mechanical heart valves (MHV). While low molecular weight heparins (LMWH) are generally dosed based on weight (i.e., enoxaparin 1 mg/kg every 12 hours), data in pregnant women have shown that weight-based dosing does not consistently achieve target anti-Xa levels. In women with MHV, our practice includes titrating LMWH doses to target both trough and peak anti-Xa levels, while for those with VTE peak anti-Xa levels guide dosing.Materials/Methods
This retrospective case series included pregnant women requiring LMWH treatment doses with at least 3 peak (+/− trough) anti-Xa levels. Our primary objective was to describe the actual LMWH dose required to achieve targeted anti-Xa levels relative to weight-based dosing in patients with MHV. Secondarily, we compared the same for VTE patients; compared actual dosing between those with MHV and VTE; and examined maternal and fetal outcomes.Results/Conclusion
Women with MHV (N = 4) required greater than weight-based dosing of enoxaparin (1.35 mg/kg Q12H) to achieve targeted anti-Xa levels. Importantly, achieving target peak anti-Xa levels did not always ensure maintenance of minimum trough levels. VTE patients (N = 12) did not require more enoxaparin (0.96 mg/kg Q12H) than weight based dosing. MHV patients received more enoxaparin compared to VTE patients (P < 0.001). No bleeding or clotting complications were associated with LMWH administration. In pregnant women with MHV at high risk of thromboembolism, LMWH dosing guided by trough and peak anti-Xa levels should be considered. 相似文献68.
Wang F Kohan AB Kindel TL Corbin KL Nunemaker CS Obici S Woods SC Davidson WS Tso P 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(24):9641-9646
Apolipoprotein A-IV (apoA-IV) is secreted by the small intestine in response to fat absorption. Here we demonstrate a potential role for apoA-IV in regulating glucose homeostasis. ApoA-IV-treated isolated pancreatic islets had enhanced insulin secretion under conditions of high glucose but not of low glucose, suggesting a direct effect of apoA-IV to enhance glucose-stimulated insulin release. This enhancement involves cAMP at a level distal to Ca(2+) influx into the β cells. Knockout of apoA-IV results in compromised insulin secretion and impaired glucose tolerance compared with WT mice. Challenging apoA-IV(-/-) mice with a high-fat diet led to fasting hyperglycemia and more severe glucose intolerance associated with defective insulin secretion than occurred in WT mice. Administration of exogenous apoA-IV to apoA-IV(-/-) mice improved glucose tolerance by enhancing insulin secretion in mice fed either chow or a high-fat diet. Finally, we demonstrate that exogenous apoA-IV injection decreases blood glucose levels and stimulates a transient increase in insulin secretion in KKAy diabetic mice. These results suggest that apoA-IV may provide a therapeutic target for the regulation of glucose-stimulated insulin secretion and treatment of diabetes. 相似文献
69.
70.