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21.
M. M. Schurink T. L. Braber N. H. J. Prakken P. A. F. M. Doevendans F. J. G. Backx D. E. Grobbee R. Rienks H. M. Nathoe M. L. Bots B. K. Velthuis A. Mosterd 《Netherlands heart journal》2017,25(4):271-277
Background
Psychological distress caused by cardiovascular pre-participation screening (PPS) may be a reason not to implement a PPS program. We assessed the psychological impact of PPS, including cardiac computed tomography (CT), in 318 asymptomatic sportsmen aged ≥45 years.Methods
Coronary artery disease (CAD) was defined as a coronary artery calcium score ≥100 Agatson units and/or ≥50% luminal stenosis on contrast-enhanced cardiac CT. Psychological impact was measured with the Impact of Event Scale (IES) (seven items) on a six-point scale (grade 0–5). A sum score ≥19 indicates clinically relevant psychological distress. A Likert scale was used to assess overall experiences and impact on sports and lifestyle.Results
A total of 275 participants (86.5% response rate, 95% CI 83–90%) with a mean age of 54.5 ± 6.4 years completed the questionnaires, 48 (17.5%, 95% CI 13–22%) of whom had CAD. The median IES score was 1 (IQR 0–2, [0–23]). IES was slightly higher in those with CAD (mean rank 175 vs. 130, p < 0.001). One participant (with CAD) experienced clinically relevant psychological distress (IES = 23). Participants reported numerous benefits, including feeling safer exercising (58.6%, 95% CI 53–65%) and positive lifestyle changes, especially in those with CAD (17.2 vs. 52.1%, p < 0.001). The majority were satisfied with their participation (93.8%, 95% CI 91–97%).Conclusion
Cardiovascular PPS, including cardiac CT, causes no relevant psychological distress in older sportsmen. Psychological distress should not be a reason to forego screening in sportsmen.22.
Eric Struyf Wiktor Kotowski Sander Jacobs Stefan Van Damme Kris Bal Wout Opdekamp Hans Backx Dimitri Van Pelt Patrick Meire 《Hydrobiologia》2011,674(1):41-50
Despite the growing concern about the importance of silicon (Si) in controlling ecological processes in aquatic ecosystems,
little is known about its processing in riparian vegetation, especially compared to nitrogen (N) and phosphorus (P). We present
experimental evidence that relative plant uptake of N and P compared to Si in riparian vegetation is dependent on mowing practices,
water-logging and species composition. Results are obtained from a controlled and replicated mesocosm experiment, with a full-factorial
design of soil water logging and mowing management. In our experiments, the Si excluding species Plantago lanceolata was dominant in the mown and non-waterlogged treatments, while Si accumulating meadow grasses and Phalaris arundinacea dominated the waterlogged treatments. Although species composition, management and soil moisture interacted strongly in their
effect on relative Si:N and Si:P uptake ratios, the uptake of N to P remained virtually unchanged over the different treatments.
Our study sheds new light on the impact of riparian wetland ecosystems on nutrient transport to rivers. It indicates that
it is essential to include Si in future studies of the impact of riparian vegetation on nutrient transport, as these are often
implemented as a measure to moderate excessive N and P inputs. 相似文献
23.
A. J. Pérez Matos R. N. Planken B. J. Bouma M. Groenink A. P. C. M. Backx R. J. de Winter D. R. Koolbergen B. J. M. Mulder S. M. Boekholdt 《Netherlands heart journal》2014,22(5):240-245
Patients with congenital heart disease corrected in early childhood may later in life present with cardiac symptoms caused by other associated congenital anomalies that were initially not diagnosed. Nowadays, several noninvasive imaging modalities are available for the visualisation of cardiac anatomy in great detail. We describe two patients with an unroofed coronary sinus, a rare congenital anomaly which could be diagnosed using a combination of modalities including echocardiography, cardiac CT and cardiac MRI. 相似文献
24.
Bryce, J. H. and ap Rees, T. 1985. Comparison of the respiratorymetabolism of Plantago lanceolata L. and Plantago major L.J.exp. Bot. 36 15591565. The aim of this work was to discover if the respiratory metabolismof the roots of Plantago lanceolata L. differed from that ofthe roots of Plantago major L. Measurements of oxygen uptakeand dry weight of excised root systems during growth of seedlingsprovided evidence that the two species differed in the amountof respiration needed to support a given increase in dry weight.Excised root systems were given a 6-h pulse in [U-14C]sucrosefollowed by a 16.5-h chase in sucrose. The detailed distributionof 14C amongst the major components of the roots at the endof the pulse and the chase revealed no significant differencebetween the two species. Patterns of 14CO2 production from [1-14C],[2-14C], [3,4-14C], and [6-14C]glucose of excised root systemsfrom plants of three ages were similar for the two species.It is suggested that there is no conclusive evidence for anysignificant inherent difference in the respiratory metabolismof the roots of the two species. Key words: 14C sugar metabolism, respiration, roots, Plantago 相似文献
25.
Rapid recycling of triose phosphates in oak stem tissue 总被引:10,自引:3,他引:7
S. A. HILL J. S. WATERHOUSE E. M. FIELD V. R. SWITSUR T. AP REES 《Plant, cell & environment》1995,18(8):931-936
We report the carbon-13 and oxygen-18 isotope ratios in cellulose from the early and late wood of pedunculate oak (Quercus robur L.). The δ13 C value of the early wood correlates best with that of the late wood of the previous year. The δ18O value of the early wood correlates best with that of the late wood of the same year. We suggest that a biochemical explanation of these data is that there is a rapid cycle between hexose monophosphates and triose phosphates in oak stem tissue during cellulose synthesis. Evidence in support of this explanation is provided by the intramolecular distribution of 14C in labelled fructose extracted from cores of wood that had been supplied with [1?14C]- and [6-14C]glucose. 相似文献
26.
CM Ward AP Wilkinson S Bramham HA Lee HW-S Chan GW Butcher A Hutchings MRA Morgan 《Mycotoxin Research》1990,6(2):73-83
From a single aflatoxin B1 oxime — bovine serum albumin conjugate, polyclonal and monoclonal antibody preparations were produced. The four rabbit polyclonal antisera were specific for aflatoxin Bi in a microtitration plate enzyme — linked immunosorbent assay. The monoclonal antibodies showed a wide range of differing specificities, recognizing, for example, aflatoxins B1, B2, G1 and G2; B1 and B2; B1 and G1; and G1 alone. No antibody preparations reacted with aflatoxin M1. The significance of these results to the strategy of anti-aflatoxin antibody production for use in quantitative enzyme immunoassays is discussed. 相似文献
27.
X Wu J Yin J Simpson KH Kim S Gu JH Hong P Bayliss PH Backx BG Neel T Araki 《Molecular and cellular biology》2012,32(19):3872-3890
Noonan syndrome (NS) is a relatively common autosomal dominant disorder characterized by congenital heart defects, short stature, and facial dysmorphia. NS is caused by germ line mutations in several components of the RAS-RAF-MEK-extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathway, including both kinase-activating and kinase-impaired alleles of RAF1 (~3 to 5%), which encodes a serine-threonine kinase for MEK1/2. To investigate how kinase-impaired RAF1 mutants cause NS, we generated knock-in mice expressing Raf1(D486N). Raf1(D486N/+) (here D486N/+) female mice exhibited a mild growth defect. Male and female D486N/D486N mice developed concentric cardiac hypertrophy and incompletely penetrant, but severe, growth defects. Remarkably, Mek/Erk activation was enhanced in Raf1(D486N)-expressing cells compared with controls. RAF1(D486N), as well as other kinase-impaired RAF1 mutants, showed increased heterodimerization with BRAF, which was necessary and sufficient to promote increased MEK/ERK activation. Furthermore, kinase-activating RAF1 mutants also required heterodimerization to enhance MEK/ERK activation. Our results suggest that an increased heterodimerization ability is the common pathogenic mechanism for NS-associated RAF1 mutations. 相似文献
28.
29.
Rafael AP Guércio Anna Shevchenko Andrej Shevchenko Jorge L López-Lozano Jaime Paba Marcelo V Sousa Carlos AO Ricart 《Proteome science》2006,4(1):11-14
Background
Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Previous studies have demonstrated that the biological and pharmacological activities of B. atrox venom alter with the age of the animal. Here, we present a comparative proteome analysis of B. atrox venom collected from specimens of three different stages of maturation: juveniles, sub-adults and adults. 相似文献30.
Gramacho KP Gonçalves LS Stort AC Noronha AB 《Genetics and molecular research : GMR》2003,2(3):309-316
Hygienic behavior is a desirable trait in honey bees (Apis mellifera L.), as hygienic bees quickly remove diseased brood, interrupting the infectious cycle. Hygienic lines of honey bees appear to be more sensitive to the odors of dead and diseased honey bee brood, and Africanized honey bees are generally more hygienic than are European honey bees. We compared the number of sensilla placodea, antennal sensory structures involved in the perception of odor, in 10 bees from each of six hygienic and four non-hygienic colonies of Africanized honey bees. The sensilla placodea of three of the terminal segments (flagellomeres) of the right antenna of each bee were counted with a scanning electron microscope. There were no significant differences in the mean numbers of sensilla placodea between the hygienic and non-hygienic bees, though the variance was higher in the hygienic group. Flagellomere 4 had significantly more sensilla placodea than flagellomeres 6 and 8. However, there was no significant difference between the other two flagellomeres. As hygienic bees are capable of identifying dead, injured, or infested brood inside a capped brood cell, sensilla placodea probably have an important role in enabling worker bees to sense sick brood. However, we did not find greater numbers of this sensory structure in the antennae of hygienic, compared to non-hygienic Africanized honey bees. 相似文献