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131.
132.
IntroductionSeaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.MethodsThe aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.ResultsCadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.DiscussionNew maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury. 相似文献
133.
Crosslinking mass spectrometry captures protein structures in solution. The crosslinks reveal spatial proximities as distance restraints, but do not easily reveal which of these restraints derive from the same protein conformation. This superposition can be reduced by photo-crosslinking, and adding information from protein structure models, or quantitative crosslinking reveals conformation-specific crosslinks. As a consequence, crosslinking MS has proven useful already in the context of multiple dynamic protein systems. We foresee a breakthrough in the resolution and scale of studying protein dynamics when crosslinks are used to guide deep-learning-based protein modelling. Advances in crosslinking MS, such as photoactivatable crosslinking and in-situ crosslinking, will then reveal protein conformation dynamics in the cellular context, at a pseudo-atomic resolution, and plausibly in a time-resolved manner. 相似文献
134.
Rosamarie Frieri William Fisher Rosenberger Nancy Flournoy Zhantao Lin 《Biometrics》2023,79(3):2565-2576
When there is a predictive biomarker, enrichment can focus the clinical trial on a benefiting subpopulation. We describe a two-stage enrichment design, in which the first stage is designed to efficiently estimate a threshold and the second stage is a “phase III-like” trial on the enriched population. The goal of this paper is to explore design issues: sample size in Stages 1 and 2, and re-estimation of the Stage 2 sample size following Stage 1. By treating these as separate trials, we can gain insight into how the predictive nature of the biomarker specifically impacts the sample size. We also show that failure to adequately estimate the threshold can have disastrous consequences in the second stage. While any bivariate model could be used, we assume a continuous outcome and continuous biomarker, described by a bivariate normal model. The correlation coefficient between the outcome and biomarker is the key to understanding the behavior of the design, both for predictive and prognostic biomarkers. Through a series of simulations we illustrate the impact of model misspecification, consequences of poor threshold estimation, and requisite sample sizes that depend on the predictive nature of the biomarker. Such insight should be helpful in understanding and designing enrichment trials. 相似文献
135.
136.
David L. Musso Nariman B. Mehta Francis E. Soroko Robert M. Ferris Elizabeth B. Hollingsworth Bernard T. Kenney 《Chirality》1993,5(7):495-500
The synthesis of the enantiomers of bupropion, (rac)-2-tert-butylamino-3′-chloropropiophenone 1 (Wellbutrin®) is described. The enantiomers were compared with the racemate in both the tetrabenazine-induced sedation model and the inhibition of uptake of biogenic amine assay. No significant differences were found in their potencies to reverse tetrabenazine-induced sedation in mice or in their IC50 values as inhibitors of biogenic amine uptake into nerve endings obtained from mouse brain. © 1993 Wiley-Liss, Inc. 相似文献
137.
《Revista espa?ola de geriatría y gerontología》2023,58(6):101388
Background and objectiveMore than half of institutionalized older people need a emergency department visit annually, with high resources consumption and higher risk of adverse events, due to high complexity. Direct admission to Acute Geriatric Unit (AGU), after geriatric consultant and nursing home medical team assessment, could be a safety and effective alternative to emergency department (ED) admission.MethodsRetrospective observational study of AGU patients admitted by Nursing Home Geriatric Team between January, 1st and December, 31st, 2021. Planned admissions and SARS-CoV-2 positive patients were excluded. Medical (sociodemographic, clinical, functional and cognitive) records and outcomes data (inpatient mortality, hospital and ED lenght of stay, transfer to ED and delirium within 48 h after admission, hospital discharge location) were collected.ResultsTwo hundred and six patients directly admitted, 101 through ED (N 307). 62.5% with Barthel index <40, 65% with dementia, 56.4% with Charlson index ≥3. Inpatient mortality was 14.6% in direct admission, 20.8% in ED referral group, p = 0.14. Hospital lenght of stay was 9.61 ± 6.01 days in direct admission, 11.22 ± 5.36 days in ED group, p = 0.02. 27.7% of patients with delirium in direct admission and 36.6% in ED group; only one patient was transferred to ED, within 48 h after admission.ConclusionsDirect admission is a safety and effective alternative to ED referral in institutionalized older people after geriatric assessment, due to no increased mortality, shorter length of stay and hospital cost reduction. 相似文献
138.
Michael Norton-Griffiths 《Biodiversity and Conservation》1996,5(12):1557-1577
This paper discusses policy responses to the potential loss of biodiversity in the Mara Area of Kenya from the conversion of essentially wild and undeveloped rangeland to developed agriculture. Property rights are central to the debate, and raise two fundamental issues. First, to what extent do the Maasai, the traditional users and owners of the land, have the right to benefit from the development potential of their land to further their economic, social and political standing, even if by so doing they create domestic and global externalities through the loss of biodiversity. Second, if the state alienates their development rights in the name of conservation, then to what extent should the state compensate the Maasai for their lost economic opportunities. To the Maasai, conservation as implemented through Government policy is a publicc bad: they are denied access to resources, their costs of production are significantly increased, and development is slowed down or actively discouraged. A cost:benefit analysis suggests that it is neither supportable nor sustainable to condemn the Maasai to a poverty trap on behalf of conservation, and that it is instead socially prolitable for the Kenyan Government to meet in full their opportunity costs of forgone economic benefits. 相似文献
139.
Dog-DAT: a direct agglutination test using stabilized, freeze-dried antigen for the serodiagnosis of canine visceral leishmaniasis 总被引:2,自引:0,他引:2
Linda Oskam Rob J. Slappendel Eef G.M. Beijer Nel C.M. Kroon Cor W. van Ingen Seray Özensoy Yusuf Özbel Wiepko J. Terpstra 《FEMS immunology and medical microbiology》1996,16(3-4):235-239
Abstract We have evaluated the use of an improved direct agglutination test (DAT) based on stable, freeze-dried antigen for the detection of anti- Leishmania antibodies in canine serum samples. With a cut-off value of 1:640, the sensitivity of the DAT was shown to be 100% and the specificity of the test was 98.8%. 相似文献
140.
Jan-Erik Wallin 《Vegetation History and Archaeobotany》1996,5(4):301-312
Compared with most parts of Europe, northern Sweden is essentially a sparsely populated wilderness. There is, however, an ever increasing body of archaeological and palaeoecological information that shows that the region has a long cultural history. In this paper, results of pollen analytical investigations from four lakes with varved lake sediments, in the province of Ångermanland, are presented. These investigations have yielded evidence of continuous and sedentary agriculture from the 6th century in the region close to the Bothnian coast and near the mouth of the large river Ångermanälven. This early agriculture appears to have been based on animal husbandry and cereal, mainly barley, cultivation. During a second farming expansion phase at ca. A.D. 1200, rye cultivation became more important. The increased farming activity during this period was most pronounced at the coast and in the river valley, but more peripheral regions away from the river valley were also exploited. During the period A.D. 1600–1800, arable farming assumed greater importance. In the first decades of the 20th century, the area under cultivation declined, cereal cultivation mostly ceased and the fields were used for pasture. 相似文献