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Choong Nam Shim Hyunsoo Chung Jun Chul Park Hyuk Lee Sung Kwan Shin Sang Kil Lee Yong Chan Lee 《Surgical endoscopy》2015,29(7):1787-1794
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Effects of aging on left atrial reservoir, conduit, and booster pump function: a multi-institution acoustic quantification study 总被引:12,自引:0,他引:12
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![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Spencer KT Mor-Avi V Gorcsan J DeMaria AN Kimball TR Monaghan MJ Perez JE Weinert L Bednarz J Edelman K Kwan OL Glascock B Hancock J Baumann C Lang RM 《Heart (British Cardiac Society)》2001,85(3):272-277
OBJECTIVE—To assess the feasibility of measuring left atrial (LA) function with acoustic quantification (AQ) and then assess the effects of age and sex on LA reservoir, conduit, and booster pump function.
PATIENTS AND SETTING—165 subjects without cardiovascular disease, 3-79 years old, were enrolled by six tertiary hospital centres.
INTERVENTIONS—Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line.
MAIN OUTCOME MEASURES—Parameters of LA performance according to age and sex.
RESULTS—Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function.
CONCLUSIONS—LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.
Keywords: aging; atrium; echocardiography 相似文献
PATIENTS AND SETTING—165 subjects without cardiovascular disease, 3-79 years old, were enrolled by six tertiary hospital centres.
INTERVENTIONS—Continuous LA AQ area data were acquired and signal averaged to form composite waveforms which were analysed off-line.
MAIN OUTCOME MEASURES—Parameters of LA performance according to age and sex.
RESULTS—Signal averaged LA waveforms were sufficiently stable and detailed to allow automated analysis in all cases. An age related increase in LA area was noted. LA reservoir function did not vary with age or sex. All parameters of LA passive and active emptying revealed a significant age dependency. Overall, the passive emptying phase accounted for 66% of total LA emptying ranging from 76% in the youngest to 44% in the oldest decade. LA contraction accounted for 34% of atrial emptying in all subjects combined with the older subjects being more dependent on atrial booster pump function. When adjusted for atrial size, there were no sex related differences in LA function.
CONCLUSIONS—LA reservoir, conduit, and booster pump function can be assessed with automated analysis of signal averaged LA area waveforms. As LA performance varies with age, establishment of normal values should enhance the evaluation of pathologic states in which LA function is important.
Keywords: aging; atrium; echocardiography 相似文献
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IL‐17 Deficiency Attenuates Allograft Injury and Prolongs Survival in a Murine Model of Fully MHC‐Mismatched Renal Allograft Transplantation
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T. Kwan S. J. Chadban J. Ma S. Bao S. I. Alexander H. Wu 《American journal of transplantation》2015,15(6):1555-1567
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Murtaugh LC Stanger BZ Kwan KM Melton DA 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(25):14920-14925
Multiple cell types of the pancreas appear asynchronously during embryogenesis, which requires that pancreatic progenitor cell potential changes over time. Loss-of-function studies have shown that Notch signaling modulates the differentiation of these progenitors, but it remains unclear how and when the Notch pathway acts. We established a modular transgenic system to heritably activate mouse Notch1 in multiple types of progenitors and differentiated cells. We find that misexpression of activated Notch in Pdx1-expressing progenitor cells prevents differentiation of both exocrine and endocrine lineages. Progenitors remain trapped in an undifferentiated state even if Notch activation occurs long after the pancreas has been specified. Furthermore, endocrine differentiation is associated with escape from this activity, because Ngn3-expressing endocrine precursors are susceptible to Notch inhibition, whereas fully differentiated endocrine cells are resistant. 相似文献