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1.
Purified cyanobacterial lipopolysaccharide (LPS) was not acutely toxic to three aquatic invertebrates (Artemia salina, Daphnia magna and Daphnia galeata) in immersion trials. However, pre-exposure (24 h) to 2 ng mL−1 LPS increased the LC50 of microcystin-LR significantly in all 3 species. Similar results were observed with A. salina pre-treated with the same concentration of cyanobacterial LPS and subsequently exposed to cylindrospermopsin, increasing the LC50 by 8. The findings indicate the need to include exposures to defined combinations of cyanotoxins, and in defined sequences, to understand the contributions of individual cyanotoxins in accounting for cyanobacterial toxicity to invertebrates in natural aquatic environments. 相似文献
2.
C. J. McKenna M. B. Codd H. A. McCann D. D. Sugrue 《Irish journal of medical science》1996,165(3):157-158
To establish current national clinical practice in the care of patients with acute myocardial infarction (AMI), a questionnaire survey of 50 consultant physicians currently working in the Republic of Ireland was carried out. There were 45 (90%) respondants. 32/45 (71%) give thrombolysis in CCU only; 13/45 (29%) give thrombolysis in casualty also. Streptokinase (Stk) is the first choice thrombolytic agent for the majority. 14/45 (31%) use tPA for anterior AMI in patients under 60 years. Angiotensin converting enzyme (ACE) inhibitors are given by 34/45 (76%) to patients with evidence of left ventricular dysfunction. ACE inhibitors are neither used routinely nor are they prescribed in the first three days after the AMI by the majority of the physicians surveyed. Serum magnesium is checked routinely by 5/45 (11%) and intravenous magnesium is given routinely by 5/45 (11%). The percentage of AMI patients considered for angiography varied from 10–50%. Despite reports from randomised, controlled trials showing reduced mortality in patients given tPA (versus Stk), routine early ACE inhibition and intravenous magnesium post-AMI, most clinicians in Ireland use streptokinase, selective late ACE inhibition and no magnesium. The reasons for the dichotomy between the favourable results of randomised clinical trials and routine practice are speculative. 相似文献
3.
Because of complexities in platelet serotonin uptake dynamics, we studied the influence of the time of day and year as well as the subject's age on uptake parameters. While the assay itself was quite reproducible, and the kinetic parameters of 5 HT uptake were stable over a few days, at a given time, within an individual, the variance was quite large when samples from different times of the day or year or from different individuals were compared. An inverse relationship between V
max (moles/cell number/time) and platelet number was found in data from a group of individuals, suggesting regulation of V
max not at the level of uptake capacity per cell, but in a manner that somehow takes into consideration the number of platelets in the subject's plasma. Indeed, expressing V
max in a new way (called total V
max), not based on V
max per cell or per 107 cells but for the total number of platelets in the volume of PRP used, greatly reduced the scatter in the between-individuals and across-time data. While V
max (moles/cell number/time) exhibited only a trend toward reduction with age, for example, the decline in total V
max with subject age was statistically significant. It is suggested that total V
max (moles/time) may be a more physiologically relevant expression for an uptake function than V
max (moles/time/cell number). 相似文献
4.
Twenty-five patients were treated for retained, recurrent, or primary common duct stones by permanent drainage of the biliary tract with external choledochoduodenostomy. Twenty-one patients had common duct stones which became evident two to fifty years after the initial biliary tract procedure and which may represent stones formed in the common duct. Three recent patients had a clinical history of primary common duct stones, had stones which were soluble in chloroform-methanol solution, and had hepatic bile which was lithogenic as determined by evaluating the molar percentage of cholesterol, phospholipid, and bile salt in bile samples obtained at the time of choledochoduodenostomy. These data suggest that further stone formation is possible and that permanent bypass of the sphincter of Oddi is indicated to prevent recurrent bile duct obstruction. Long-term evaluation of the results of external choledochoduodenostomy indicates that the procedure is safe and effective in the prevention of recurrent biliary tract calculi. 相似文献
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Diverse taxa of cyanobacteria produce beta-N-methylamino-L-alanine, a neurotoxic amino acid
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Cox PA Banack SA Murch SJ Rasmussen U Tien G Bidigare RR Metcalf JS Morrison LF Codd GA Bergman B 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(14):5074-5078
Cyanobacteria can generate molecules hazardous to human health, but production of the known cyanotoxins is taxonomically sporadic. For example, members of a few genera produce hepatotoxic microcystins, whereas production of hepatotoxic nodularins appears to be limited to a single genus. Production of known neurotoxins has also been considered phylogenetically unpredictable. We report here that a single neurotoxin, beta-N-methylamino-L-alanine, may be produced by all known groups of cyanobacteria, including cyanobacterial symbionts and free-living cyanobacteria. The ubiquity of cyanobacteria in terrestrial, as well as freshwater, brackish, and marine environments, suggests a potential for wide-spread human exposure. 相似文献
9.
Linda Broer Veryan Codd Dale R Nyholt Joris Deelen Massimo Mangino Gonneke Willemsen Eva Albrecht Najaf Amin Marian Beekman Eco J C de Geus Anjali Henders Christopher P Nelson Claire J Steves Margie J Wright Anton J M de Craen Aaron Isaacs Mary Matthews Alireza Moayyeri Grant W Montgomery Ben A Oostra Jacqueline M Vink Tim D Spector P Eline Slagboom Nicholas G Martin Nilesh J Samani Cornelia M van Duijn Dorret I Boomsma 《European journal of human genetics : EJHG》2013,21(10):1163-1168
Telomere length (TL) has been associated with aging and mortality, but individual differences are also influenced by genetic factors, with previous studies reporting heritability estimates ranging from 34 to 82%. Here we investigate the heritability, mode of inheritance and the influence of parental age at birth on TL in six large, independent cohort studies with a total of 19 713 participants. The meta-analysis estimate of TL heritability was 0.70 (95% CI 0.64–0.76) and is based on a pattern of results that is highly similar for twins and other family members. We observed a stronger mother–offspring (r=0.42; P-value=3.60 × 10−61) than father–offspring correlation (r=0.33; P-value=7.01 × 10−5), and a significant positive association with paternal age at offspring birth (β=0.005; P-value=7.01 × 10−5). Interestingly, a significant and quite substantial correlation in TL between spouses (r=0.25; P-value=2.82 × 10−30) was seen, which appeared stronger in older spouse pairs (mean age ≥55 years; r=0.31; P-value=4.27 × 10−23) than in younger pairs (mean age<55 years; r=0.20; P-value=3.24 × 10−10). In summary, we find a high and very consistent heritability estimate for TL, evidence for a maternal inheritance component and a positive association with paternal age. 相似文献
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