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51.
52.
Diverse taxa of cyanobacteria produce beta-N-methylamino-L-alanine, a neurotoxic amino acid 下载免费PDF全文
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
53.
Combination treatment of IFNalpha2b and ribavirin in patients with chronic hepatitis C and persistently normal ALTs 总被引:3,自引:0,他引:3
Erhardt A Behlen-Wilm U Adams O Donner A Heintges T Häussinger D 《Digestive diseases and sciences》2003,48(5):921-925
Combination therapy of interferon-2b and ribavirin was prospectively evaluated in 20 patients with chronic replicative hepatitis and persistently normal ALTs. Patients with normal ALTs on three or more occasions within 6 months received interferon-2b 3 MU three times a week with ribavirin 1000–1200 mg everyday for 12 months and had a follow-up of 6 months. HCV genotype 1 was found in 16, and HCV genotype 2 or 3 in 4 patients. No patient experienced an ALT elevation during therapy. Ten of 20 patients (50%) cleared virus at the end of treatment. In an intent-to-treat analysis, a sustained virological response (SR) was achieved in 8 of 20 patients (40%). Nonresponse occurred in 5 patients. Relapse and breakthrough were seen in 2 patients each. Treatment was discontinued in 3 patients due to side effects. Interferon (IFN) ribavirin combination therapy is effective in patients with normal ALTs and appears superior to IFN monotherapy. 相似文献
54.
Ulla A. Botha Marise Coetzee Liezl Koen Dana J.H. Niehaus 《Archives of Psychiatric Nursing》2018,32(3):384-389
Introduction
Pressure on inpatient beds often results in premature discharges, which may precipitate early readmission. This has prompted an increased interest in transitional care interventions to bridge the gap between in- and outpatient care to reduce such readmissions. Our study aimed to assess the effect of a Transitional Care Service (TCS) on readmission rates in a high pressure inpatient service which utilizes a premature discharge policy to address bed pressures.Methods
Sixty male patients identified for crisis discharge were offered a TCS for the first ninety days after discharge. Patients received a structured intervention consisting of four phone calls and one home visit, focusing on maintaining adherence, appointment reminders and psychoeducation. The TCS patients were retrospectively compared to a matched control group in terms of readmission after 90 days. Data was collected on adherence to medication, attendance of appointments and incidence of substance use.Results
There was no significant difference in readmission rates. Prevalence of substance use was very high (90%), especially methamphetamine use (48%). Adherence dropped from 45% (n = 27) at one week post-discharge to 25% (n = 15) at 90 days.Conclusion
Structured telephone-based transitional interventions have no effect on readmission rates in this setting. Prematurely discharged patients require more comprehensive support with focus on comorbid substance use. 相似文献55.
56.
Noriaki Moriyama Teemu Laakso Peter Raivio Sebastian Dahlbacka Eeva-Maija Kinnunen Tatu Juvonen Antti Valtola Annastiina Husso Maina P. Jalava Tuomas Ahvenvaara Tuomas Tauriainen Jarkko Piuhola Asta Lahtinen Matti Niemelä Timo Mäkikallio Marko Virtanen Pasi Maaranen Markku Eskola Mika Laine 《The Canadian journal of cardiology》2021,37(1):37-46
BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality. 相似文献
57.
Nico Dragano Pablo Emilio Verde Susanne Moebus Andreas Stang Axel Schmermund Ulla Roggenbuck Stefan M?hlenkamp Richard Peter Karl-Heinz J?ckel Raimund Erbel Johannes Siegrist 《European journal of cardiovascular prevention and rehabilitation》2007,14(4):568-574
BACKGROUND: Social inequalities of manifest coronary heart diseases are well documented in modern societies. Less evidence is available on subclinical atherosclerotic disease despite the opportunity to investigate processes underlying this association. Therefore, we examined the relationship between coronary artery calcification as a sign of subclinical coronary atherosclerosis, socio-economic status and established cardiovascular risk factors in a healthy population. DESIGN: Cross-sectional. METHODS: In a population-based sample of 4487 men and women coronary artery calcification was assessed by electron beam computed tomography quantified by the Agatston score. Socio-economic status was assessed by two indicators, education and income. First, we investigated associations between the social measures and calcification. Second, we assessed the influence of cardiovascular risk factors on this association. RESULTS: After adjustment for age, men with 10 and less years of formal education had a 70% increase in calcification score compared with men with high education. The respective increase for women was 80%. For income the association was weaker (among men 20% higher for the lowest compared with the highest quartile; and among women 50% higher, respectively). Consecutive adjustment for cardiovascular risk factors significantly attenuated the observed association of socio-economic status with calcification. CONCLUSIONS: Social inequalities in coronary heart diseases seem to influence signs of subclinical coronary atherosclerosis as measured by coronary artery calcification. Importantly, cumulation of major cardiovascular risk factors in lower socio-economic groups accounted for a substantial part of this association. 相似文献
58.
Kai O. Lindros Ph.D. Pentti Sipponen M.D. Pekka Pikkarainen M.D. Ulla Turunen M.D. Mikko Salaspuro M.D. 《Alcoholism, clinical and experimental research》1979,3(1):78-82
Rats chronically fed ethanol developed liver injury only if they also received low doses of the alcohol dehydrogenase inhibitor, 4-methylpyrazole, suggesting that the consistency of the influence of ethanol and its metabolism, rather than the level of acetaldehyde or the degree of the metabolic effects, contributes to the pathogenesis of alcoholic liver damage. 相似文献
59.
60.
Knut Dehnert Ulla Raab Carmelo Perez-Alvarez Thomas Steffens Gabriele Bolte Hermann Fromme 《International journal of audiology》2015,54(10):665-673
Objective: To investigate total leisure noise exposure among adolescents and to assess its association with hearing. Design: Based on self-reported time spent on 19 leisure activities and associated mean sound pressure levels reported in the literature, total leisure noise exposure was evaluated and compared to noise at work limits (> 85 dB(A) = hazardous) in a cross-sectional survey. Tympanometry and pure-tone audiometry was performed in sound isolated rooms. Study sample: The study sample consists of 2143 pupils attending grade nine in any school in a German city 2009–2011 (mean age: 15.4 years; range: 13–19 years). Audiometric data were available for 1837 (85.8%) pupils (53.9% girls). Results: 41.9% of the 2143 adolescents who had provided self-reported data on leisure activities associated with noise exposure were estimated to be hazardously exposed to leisure time noise. The interaction of gender with total leisure time noise exposure was not significant. No association between leisure time noise exposure and audiometric notches could be detected. Conclusion: While hearing loss seems seldom in this age group, a high proportion of adolescents aged 15–16 years are exposed to noise levels during leisure time bearing long-term risks of hearing loss. 相似文献