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排序方式: 共有1094条查询结果,搜索用时 43 毫秒
1.
2.
Carotid baroreflex function ceases
during vasovagal syncope 总被引:2,自引:0,他引:2
Shigehiko Ogoh PhD Stefanos Volianitis PhD Peter B. Raven PhD Niels H. Secher MD 《Clinical autonomic research》2004,14(1):30-33
Abstract. Despite the arterial baroreflex control of heart rate and
blood pressure, vasovagal syncope is a common cause of loss of
consciousness in people exposed to stimuli that reduce the
central blood volume, such as head-up tilt. Carotid baroreflex
function was evaluated using a rapid pulse train of neck
pressure and neck suction in three conscious volunteers who
developed a vasovagal episode during head-up tilt. The maximal
gain of the carotid-heart rate and carotid-blood pressure
baroreflex function curves were identified as measures of
carotid baroreceptor responsiveness. When presyncopal symptoms
developed, one further baroreflex assessment was obtained before
the subjects were returned to the supine position. The
bradycardia and hypotension exhibited during pre-syncope and
syncope reflected a leftward and downward relocation of both the
cardiac and vasomotor stimulusresponse curves. In addition,
during the vasovagal syncope, baroreflex control was suppressed
as blood pressure remained low during neck pressure stimuli. In
conclusion, arterial baroreflex function ceases during vasovagal
syncope. 相似文献
3.
Prognostic significance of declining ankle-brachial index values in patients with suspected or known peripheral arterial disease. 总被引:2,自引:1,他引:1
H H H Feringa S E Karagiannis O Schouten R Vidakovic V H van Waning E Boersma G Welten J J Bax D Poldermans 《European journal of vascular and endovascular surgery》2007,34(2):206-213
BACKGROUND: Peripheral arterial disease (PAD) is a risk factor for cardiovascular events. This study assessed the prognostic significance of repeated ankle-brachial index (ABI) measurements at rest and after exercise in patients with PAD receiving conservative treatment. METHODS: In a cohort study of 606 patients (mean age 62+/-12 years, 68% male), ABI at rest and after exercise was measured at baseline and after 1 year. Patients with reductions in ABI were divided into three equally-sized groups (minor, intermediate and major reductions) and were compared to patients without reductions. During a mean follow-up of 5+/-3 years, all-cause mortality, cardiac events, stroke and progression to kidney failure were noted. RESULTS: Death was recorded in 83 patients (14%) of which 49% were due to cardiac causes. Non-fatal myocardial infarction occurred in 38 patients (6%), stroke in 46 (8%) and progression to kidney failure in 35 (6%). By multivariate analysis, patients with major declines in resting (>20%) and post-exercise (>30%) ABI were at increased risk of all-cause mortality (HR: 3.3, 95% CI: 1.5-7.2, HR: 3.0, 95% CI: 1.4-6.4, respectively), cardiac events (HR: 3.1, 95% CI: 1.3-7.2, HR: 2.4, 95% CI: 1.1-5.6, respectively), stroke (HR: 4.2, 95% CI: 1.6-10.4, HR: 3.9, 95% CI: 1.4-10.2, respectively) and kidney failure (HR: 2.7, 95% CI: 1.1-7.5, HR: 6.9, 95% CI: 1.5-31.5, respectively), compared to patients with no declines in ABI. CONCLUSIONS: This study shows that major 1-year declines in resting and post-exercise ABI are associated with all-cause mortality, cardiac events, stroke and kidney failure in patients with PAD. 相似文献
4.
Ara G. Hovanessian Eliane Meurs Odile Aujean Catherine Vaquero Simon Stefanos Ernesto Falcoff 《Virology》1980,106(1):195-204
Treatment of mouse L929 cells with immune T (type II) interferon resulted in the induction of two double-stranded (ds) RNA-dependent enzymes which have been described previously in viral (type I) interferon-treated cells: pppA(2′p5′A)n synthetase and protein kinase(s). The induction of these enzymes by T interferon was blocked by anti-T but not by antiviral interferon serum. The kinetics of the development of the antiviral state along with a comparison of the levels of pppA(2′p5′A)n synthetase and protein kinase in T and viral interferon-treated cells were investigated. In addition, [35S]methionine-labeled extracts from control, T, and viral inteferon-treated cells were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional gel electrophoresis. Extracts from cells treated with either type of interferon were found to contain several identical proteins, of estimated molecular weights 60,000, 88,000, and 120,000, which were absent or found at much lower levels in preparations from control cells. The newly synthesized proteins can be partially purified by chromatography on columns of poly(I)·poly(C)-Sepharose, thus providing a convenient method for their further characterization. These results show that treatment of cells with T interferon results in the induction of intracellular events identical to those observed in viral interferon-treated cells. 相似文献
5.
Athanasios Zahariou Maria Karamouti George Karagiannis Polyanthi Papaioannou 《Journal of neurology》1995,242(Z2):S61-S62
Poster Session 1
Child neurology 相似文献6.
Christopher J. Coroneos Yu-Li Lin Chris Sidey-Gibbons Malke Asaad Brian Chin Stefanos Boukovalas Margaret S. Roubaud Makesha Miggins Donald P. Baumann Anaeze C. Offodile 《Journal of the American College of Surgeons》2021,232(3):253-263
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7.
Sara Ariotti Maarten van Leeuwen Salvatore Brugaletta Sergio Leonardi K. Martijn Akkerhuis Stefano F. Rimoldi Gladys N. Janssens Luis Ortega-Paz Umberto Gianni Jan C. van den Berge Alexios Karagiannis Stephan Windecker Marco Valgimigli 《Journal of the American College of Cardiology》2018,71(11):1289-1291
8.
9.
Stefanos Tyrovolas MSc PhD cand. George Pounis MSc Vassiliki Bountziouka MSc PhD cand. Evangelos Polychronopoulos MD PhD 《Journal of nutrition in gerontology and geriatrics》2013,32(3):311-324
The aim of the present work was to evaluate the repeatability and the validity of a short food frequency questionnaire (FFQ) that could be used for older people living in Mediterranean areas. The semi-quantitative FFQ included questions regarding the frequency of consumption of the main food groups and beverages typically consumed in the Mediterranean areas as well as some questions regarding eating habits of older persons. During 2006–2007, for the repeatability assessment (within 10–30 days), 150 individuals (51 ± 17 yrs, 40% males) were studied, while another 190 individuals (74 ± 9 yrs, 52% males) were enrolled for the validation purposes. Agreement of the FFQ with the 3-day food records was evaluated using the Bland–Altman method and the Kendall's tau-b coefficient. Repeatability was tested using the Cohen's kappa coefficient. Between 3-day food records and the FFQ, good agreement for alcohol (tau-b = 0.64, p < 0.001) was found, while moderate agreement for food and beverage groups of greens (tau-b = 0.32, p < 0.001), fruits (tau-b = 0.35, p < 0.001), cereals (tau-b = 0.61, p < 0.001), sweets (tau-b = 0.51, p < 0.001), and coffee (tau-b = 0.58, p < 0.001) was observed. Low, but still significant, agreement for fish (tau-b = 0.21, p = 0.001), legumes (tau-b = 0.23, p < 0.001), vegetables (tau-b = 0.23, p < 0.001), pasta (tau-b = 0.25, p < 0.001), potatoes (tau-b = 0.17, p = 0.006) and meat consumption (tau-b = 0.14, p < 0.001) were also found. The FFQ was also valid regarding the estimation of macronutrients and energy intake. Sensitivity analyses by sex, age category (≤ or > 75 yrs), and education status showed similar validity of the FFQ in each subgroup, except for elders older than 75 years. The repeatability of the FFQ was fair in all foods tested (Cohen's kappa coefficients varied between 0.15–0.39, p-values < 0.05). The suggested FFQ seems to be a reasonably valid and repeatable measure of dietary intake and can be used in older persons living in the Mediterranean areas. 相似文献
10.