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991.
The increased use of the automated external defibrillator (AED) contributes to the rising survival rate after sudden cardiac arrest in the Netherlands. When used, the AED records the unconscious person’s medical data (heart rhythm and information about cardiopulmonary resuscitation), which may be important for further diagnosis and treatment. In practice, ethical and legal questions arise about what can and should be done with these ‘AED data’. In this article, the authors advocate the development of national guidelines on the handling of AED data. These guidelines should serve two purposes: (1) to safeguard that data are handled carefully in accordance with data protection principles and the rules of medical confidentiality; and (2) to ensure nationwide availability of data for care of patients who survive resuscitation, as well as for quality monitoring of this care and for related scientific research. Given the medical ethical duties of beneficence and fairness, existing (sometimes lifesaving) information about AED use ought to be made available to clinicians and researchers on a structural basis. Creating a national AED data infrastructure, however, requires overcoming practical and organisational barriers. In addition, further legal study is warranted.  相似文献   
992.
Industry has an increasing interest in the use of enzymes as environmentally friendly, highly efficient, and specific bio-catalysts. Enzymes have primarily evolved to function in aqueous environments at ambient temperature and pressure. These conditions however do not always correspond with industrial processes or applications, and only a small portion of all known enzymes are therefore suitable for industrial use. Protein engineering can sometimes be applied to convey more desirable properties to enzymes, such as increased stability, but is limited to the 20 naturally occurring amino acids or homologs thereof. Using post-production modification, which has the potential to combine desirable properties from the enzyme and the conjugated compounds, enzymes can be modified with both natural and synthetic molecules. This offers access to a myriad of possibilities for tuning the properties of enzymes. At this moment, however, the effects of post-production modification cannot yet be reliably predicted. The increasing number of applications will improve this so that the potential of this technology can be fully exploited. This review will focus on post-production modification of enzymes and its use and opportunities in industry.  相似文献   
993.
The bindinf of unmodified low density lipoproteins to the plasma membrane of fibroblasts was studied at the ultrastructural level. The bound low density lipoprotein was visualized by an indirect immunoperoxidase technique, with the use of an antiserum against apoprotein B. Immunoreactive regions representing bound apoprotein B were found on the plasma membrane, in indented regions with a diameter of 0.15--0.30 micrometer and a fuzzy coat on the cytoplasmic side. Fibroblasts from a patient homozygous for hyperlipoproteinaemia type IIa showed no immunoreactive material in the indented regions. The specific 125I-labelled low density lipoprotein binding to these homozygous fibroblasts was 7% compared to control fibroblasts.  相似文献   
994.
Inshore massive corals often display bright luminescent lines that have been linked to river flood plumes into coastal catchments and hence have the potential to provide a long-term record of hinterland precipitation. Coral luminescence is thought to result from the incorporation of soil-derived humic acids transported to the reef during major flood events. Corals far from terrestrial sources generally only exhibit dull relatively broad luminescence bands, which are attributed to seasonal changes in coral density. We therefore tested the hypothesis that spectral ratios rather than conventional luminescence intensity provide a quantitative proxy record of river runoff without the confounding effects of seasonal density changes. For this purpose, we have developed a new, rapid spectral luminescence scanning (SLS) technique that splits emission intensities into red, green and blue domains (RGB) for entire cores with an unprecedented linear resolution of 71.4 μm. Since humic acids have longer emission wavelength than the coral aragonite, normalisation of spectral emissions should yield a sensitive optical humic acid/aragonite ratio for humic acid runoff, i.e., G/B ratio. Indeed, G/B ratios rather than intensities are well correlated with Ba/Ca, a geochemical coral proxy for sediment runoff, and with rainfall data, as exemplified for coral records from Madagascar. Coral cores also display recent declining trends in luminescence intensity, which are also reported in corals elsewhere. Such trends appear to be associated with a modern decline in skeletal densities. By contrast, G/B spectral ratios not only mark the impact of individual cyclones but also imply that humic acid runoff increased in Madagascar over the past few decades while coral skeletal densities decreased. Consequently, the SLS technique deconvolves the long-term interplay between humic acid incorporation and coral density that have confounded earlier attempts to use luminescence intensities as a proxy for river runoff.  相似文献   
995.
Fibroblasts from patients with the adult, juvenile, and infantile form of glycogenosis type II (Pompe disease) were cultured under standardized conditions, and the activity of acid alpha-glucosidase (E.C.3.2.1.20) towards glycogen, maltose, and 4-methylumbelliferyl-alpha-D-glucopyranoside was measured. Glycogen levels in muscle biopsies and in cultured fibroblasts from patients were determined. Residual enzyme activities varying from 7%-22% were detected in fibroblasts from patients with the adult form but not from patients with the infantile form of glycogenosis II. An inverse correlation was found between the severity of the clinical manifestation and the degree of residual enzyme activity in the fibroblasts. The kinetic and electrophoretic properties of acid alpha-glucosidase in fibroblasts from the adult patients and from control individuals were similar. Immunological studies suggested that the decrease of acid alpha-glucosidase activity is caused by a mutation that affects the production or degradation of the enzyme rather than its catalytic activity. Complementation studies were carried out by fusing fibroblasts from patients with the adult, juvenile, and infantile form of glycogenosis II, but neither conventional assays on multikaryons nor enzyme assays on single binuclear heterokaryons gave any evidence for genetic heterogeneity among these forms.  相似文献   
996.
An infant-oriented parental repertoire contributes to an infant''s development and well-being. The role of oxytocin (OT) in promoting affiliative bonds and parenting has been established in numerous animal and human studies. Recently, acute administration of OT to a parent was found to enhance the carer''s, but at the same time also the infant''s, physiological and behavioural readiness for dyadic social engagement. Yet, the exact cues that are involved in this affiliative transmission process remain unclear. The existing literature suggests that motion and vocalization are key social signals for the offspring that facilitates social participation, and that distance and motion perception are modulated by OT in humans. Here, we employed a computational method on video vignettes of human parent–infant interaction including 32 fathers that were administered OT or a placebo in a crossover experimental design. Results indicate that OT modulates parental proximity to the infant, as well as the father''s head speed and head acceleration but not the father''s vocalization during dyadic interaction. Similarly, the infant''s OT reactivity is positively correlated with father''s head acceleration. The current findings are the first to report a relationship between the OT system and parental motion characteristics, further suggesting that the cross-generation transmission of parenting in humans might be underlaid by nuanced, infant-oriented, gestures relating to the carer''s proximity, speed and acceleration within the dyadic context.  相似文献   
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Martijn Koster 《Ethnos》2014,79(2):215-237
In Brazil, citizenship rights and the institutionalisation of citizen participation have advanced significantly under the democratic regime. However, many of the urban poor are still alienated from the state and its legal system. This article argues that, to understand the citizenship of these ‘half-citizens’, it is necessary to take account of an unofficial realm of practices. I show how residents of a slum in Recife interpret and deal with the state project of registered citizenship, which finds its material expression in the compulsory carrying of identity cards. Carrying these cards is surrounded by fear of violent police control. However, obtaining identity cards through informal procedures is associated with a longing for personalised relationships with the police and other state representatives. The relationship of these residents with their identity cards is thus both fearful and affectionate, which allows us to understand their citizenship as a confluence of fear and intimacy.  相似文献   
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