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1.
Vida Jeremic Karine Sénécal Pascal Borry Davit Chokoshvili Danya F. Vears 《Journal of bioethical inquiry》2016,13(4):525-534
Participation in healthcare decision-making is considered to be an important right of minors, and is highlighted in both international legislation and public policies. However, despite the legal recognition of children’s rights to participation, and also the benefits that children experience by their involvement, there is evidence that legislation is not always translated into healthcare practice. There are a number of factors that may impact on the ability of the child to be involved in decisions regarding their medical care. Some of these factors relate to the child, including their capacity to be actively involved in these decisions. Others relate to the family situation, sociocultural context, or the underlying beliefs and practices of the healthcare provider involved. In spite of these challenges to including children in decisions regarding their clinical care, we argue that it is an important factor in their treatment. The extent to which children should participate in this process should be determined on a case-by-case basis, taking all of the potential barriers into account. 相似文献
2.
Significance of nucleotide sequence alignments: a method for random sequence permutation that preserves dinucleotide and codon usage 总被引:10,自引:0,他引:10
The similarity of two nucleotide sequences is often expressed in terms of
evolutionary distance, a measure of the amount of change needed to
transform one sequence into the other. Given two sequences with a small
distance between them, can their similarity be explained by their base
composition alone? The nucleotide order of these sequences contributes to
their similarity if the distance is much smaller than their average
permutation distance, which is obtained by calculating the distances for
many random permutations of these sequences. To determine whether their
similarity can be explained by their dinucleotide and codon usage, random
sequences must be chosen from the set of permuted sequences that preserve
dinucleotide and codon usage. The problem of choosing random dinucleotide
and codon-preserving permutations can be expressed in the language of graph
theory as the problem of generating random Eulerian walks on a directed
multigraph. An efficient algorithm for generating such walks is described.
This algorithm can be used to choose random sequence permutations that
preserve (1) dinucleotide usage, (2) dinucleotide and trinucleotide usage,
or (3) dinucleotide and codon usage. For example, the similarity of two
60-nucleotide DNA segments from the human beta-1 interferon gene
(nucleotides 196-255 and 499-558) is not just the result of their nonrandom
dinucleotide and codon usage.
相似文献
3.
Das UN 《Experimental biology and medicine (Maywood, N.J.)》2002,227(2):88-93
Estrogen, statins, and essential fatty acids and their metabolites can prevent osteoporosis. However, it is not certain how these three structurally different agents can have the same beneficial action. It is suggested that all three, in addition to their other modes of action in the prevention of osteoporosis, have the ability to augment constitutional (or endothelial) nitric oxide generation, which is known to be beneficial in osteoporosis. If so, it will be interesting to study whether nitric oxide donors and/or nitric oxide precursors can be given together with estrogen, statins, or essential fatty acids to potentiate their benefit in osteoporosis. 相似文献
4.
This response on behalf of FRAME to the European Commission's consultation on the five chapters of the Draft Report on Alternative (Non-animal) Methods for Cosmetics Testing: Current Status and Future Prospects--2010, is via a Comment in ATLA, rather than via the template supplied by the Commission. This is principally so that a number of general points about cosmetic ingredient testing can be made. It is concluded that the five draft chapters do not provide a credible basis for the Commission's forthcoming report to the European Parliament and the European Council on the five cosmetic ingredient safety issues for which the 7th Amendment to the Cosmetic Directive's ban on animal testing was postponed until 2013. This is mainly because there is insufficient focus in the draft chapters on the specific nature of cosmetic ingredients, their uses, their local effects and metabolism at their sites of application, and, in particular, on whether their possible absorption into the body would be likely to lead to their accumulation in target sites at levels approaching Thresholds of Toxicological Concern. Meanwhile, there continues to be uncertainty about how the provisions of the Cosmetics Directive should be applied, given the requirements of the REACH system and directives concerned with the safety of other chemicals and products. 相似文献
5.
The question of fertility is a major concern for young adults successfully treated for cancer, which is why semen preservation should be proposed to all adolescent boys prior to treatment of a cancer. This proposal is part of the oncologist’s approach to prevent sequelae. To ensure that semen cryopreservation is conducted under good conditions and is accepted by the adolescent, it is important to have a good understanding of the psychopathology and behaviour of adolescents with cancer: their preoccupation with their body, their appearance, their sexuality, their relationships to their peers and to their parents, their value and narcissism, their identity. This helps the clinician to understand and overcome the various reasons for their difficulty (and to lessen the painful feeling of failure) or their reticence to perform semen cryopreservation: paralysed by the diagnosis of cancer, sexual inhibition, lack of understanding and ignorance, pessimism concerning outcome, incapacity to project into the future, poor relationship with parents, discredit of parenthood, fear of transmitting the cancer, etc. A good understanding of these elements can avoid an excessively rapid acceptance of a superficial opposition to this procedure that the patient could subsequently regret. Closer collaboration should be developed between oncology-haematology departments and CECOS units to provide suitable information material to adolescents, to improve the understanding of the specific psychology of adolescents, and to understand the parents’ positions. 相似文献
6.
Patrick Bateson 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2001,32(4):1059
Evolutionary ideas and modern biological knowledge have important roles to play in the understanding of human behaviour. Nevertheless, it is deeply misleading to regard humans as robots in the grip of their genes. A well designed brain should respond to the consequences of behaviour; if an understanding of the likely consequences can be achieved without actually performing the act, then a person who knows that they will be rewarded or punished for certain acts is bound to be influenced by that knowledge. A brain designed in that way facilitates the evolution of societies with explicit social approval of certain activities and explicit disapproval of others. The evolutionary approach to psychology does not imply that individuals do not make free choices. Individuals clearly do make a big difference to what happens in their lives through their decisions. They may be surprised by the consequences of their own actions. A well designed brain should be able to anticipate the consequences of various courses of action and choose between them on the basis of their likely costs and benefits. Planning before doing is clearly of great advantage. People do make well considered decisions and they benefit from doing so. 相似文献
7.
N. M. HANCOX 《Biological reviews of the Cambridge Philosophical Society》1949,24(4):448-471
Osteoclasts, Kölliker's universal agent of bone destruction, must still be regarded as enigmatical structures. It is likely that their life span is limited to a few days. Regarded by some as resulting from fusion of relatively immobile individuals of connective tissue type, and by others of mobile cells such as macrophages, it seems a possibility that they may form from any cell, indifferently, which has assumed the 'histiocytic state'. Osteoclasts resemble histiocytes in their reaction to supravital neutral red, in their brisk motility and in the differentiation of a superficial ecto-plasmic layer into an 'undulating membrane' in tissue culture. There is no direct evidence that osteoclasts erode bone, but their constant occurrence in zones where absorption is taking place, together with the associated histological picture and especially their striated border, suggest that their presence is more than incidental. A linear orientation of cytoplasmic ultramicrons may be reflected in the striated border, which may thus constitute a cytoplasmic zone adapted for the transfer of material into or out from the cell. There is practically no evidence upon which to base an explanation of how osteoclasts could erode bone. The cells form in response to such a wide variety of normal and experimental stimuli that at least in part a local action on the bone seems likely. Local humoral factors, emanating from the bone, may be responsible for the determination of osteoclasts, and the formation of giant cells under the influence of injected phthioic acid seems to provide a valid analogy. It may be that the factors reside in the ground substance. The process of osteoclastic absorption does not appear to be regulated by the nervous system. Further experiments should be undertaken to test the ability of osteoclasts to erode bone and to ascertain whether bone about to be absorbed differs constitutionally from normal bone. 相似文献
8.
M. J. A. Simpson 《Primates; journal of primatology》1985,26(1):57-72
Special techniques are needed to help us understand the long-term effects of infants' experiences of their relationships with
their mothers, especially when direct experimental control of the interaction between mother and young is impossible, or could
distort their relationship. A classification approach is developed to show how outcomes in individuals can be predicted from
their earlier experiences and characteristics. Four-week-old rhesus monkey infants' characteristic levels of enterprise persisted
through their first year, but could be reduced in certain individuals who had been kept off their mothers by high rates of
early maternal rejection. Correlational approaches are difficult to interpret when they fail to confirm simple effects of
experience or of individual characteristics, because they are based on groups not individuals, and because certain individuals
can affect the values of correlation coefficients in ways that cannot be specified without using a classification approach.
The possible effects on correlation coefficients of inconsistent individuals, and of being unable to specify which infants
respond in which ways to relevant variables were discussed. 相似文献
9.
Genetic variation is believed to be a prerequisite for the short-and long-term survival of the plant species in their natural habitat. It depends on many environmental factors which determine the number of alleles on various loci in the genome. Therefore, it is important to understand the genetic composition and structure of the rare and endangered plant species from their natural habitat to develop successful management strategies for their conservation. However, rare and endangered plant species have low genetic diversity due to which their survival rate is decreasing in the wilds. The evaluation of genetic diversity of such species is very important for their conservation and gene manipulation. However, plant species can be conserved by in situ and in vitro methods and each has advantages and disadvantages. DNA banking can be considered as a means of complimentary method for the conservation of plant species by preserving their genomic DNA at low temperatures. Such approach of preservation of biological information provides opportunity for researchers to search novel genes and its products. Therefore, in this review we are describing some potential biotechnological approaches for the conservation and further manipulation of these rare and endangered plant species to enhance their yield and quality traits. 相似文献
10.
William Bains 《Bioscience Hypotheses》2009,2(1):1-2
Hypotheses need not be completely right to be useful. A hypothesis that explains an important aspect of the world, but not all of the world, can stimulate new ideas and new experiments which take science forward. Phlogiston is a typical case study. While not universally accepted at the time, and subsequently proved to be wrong, the hypothesis that there was a ‘fire-giving’ substance in inflammable materials prompted the development of quantitative chemistry, and the subsequent discovery of oxygen. Hypotheses today do not have to explain all aspects of the world perfectly. But they should be honest about those aspects they do not explain, and demonstrate some humility in their limitations. It is very unlikely that a single idea explains everything in a biological system. Theorists should recognise this: if they do not, their readers will, and will discount their ideas because of their lack of awareness of their context. Humility may get you a hearing. 相似文献
11.
A Weil 《Cellular and molecular biology, including cyto-enzymology》2001,47(8):1343-1351
Whatever their own policies may be, developing countries will inevitably be affected by the development of genetically-modified organisms in industrialized countries. While maintaining a cautious attitude, most of these countries wish to keep their options open, thus protecting themselves from the risk of being deprived of future technologies that might allow them to achieve self-sufficiency in food production, to resolve certain problems confronting their most vulnerable populations and to preserve the international competitiveness of their products. Companies should see that it is in their interest to help these countries implement their own policies, notably through an open attitude to industrial property. If the value of genetic engineering is thus confirmed, then it perhaps in this manner that GMOs will earn the legitimacy required to make them acceptable to the people of Northern countries where the majority of solvent markets are located. 相似文献
12.
Unproven and disproven remedies continue to abound for illnesses for which conventional treatment is only partially effective. This is particularly true with cancer, for which up to 50% of patients may be receiving unorthodox therapy. This article examines unconventional cancer remedies, their adverse effects, their common factors and the basis for their appeal, as well as what motivates and characterizes patients who choose these treatments. Also discussed is an approach that may be used by the conventional physician for patients who are likely to seek unorthodox treatment. This approach will help patients make the best decision about their treatment and protect them from the hazards of unconventional remedies. 相似文献
13.
The methodologies of classical genetics and genetic engineering can be used for the genetic improvement of entomopathogenic nematodes (EPNs) and their symbiont bacteria. Many of the complex behavioural and physiological traits which are targets for genetic improvement are likely to be controlled polygenically, thus selective breeding for improvements to these traits would be appropriate. Much basic research needs to be carried out before researchers will be able to effect improvements to EPNs and their symbionts by genetic engineering. There is a lack of basic information on the genetics and biochemistry of the characteristics that might be altered by transgenic methods in EPNs, and their bacteria, and existing transformation protocols need to be made more effective. 相似文献
14.
Pölzl C 《Progress in biophysics and molecular biology》2011,107(3):467-472
When discussing health risks for children due to electromagnetic fields it is crucial to translate scientific knowledge both into adequate protection and precautionary measures for the general public and, more particularly into specific recommendations for children. It is often aimed at influencing health-related attitudes and behaviour by means of information about health affecting behaviour, health risk factors, and health promoting possibilities. Children have to be treated differently from adults in addressing their ability and willingness to modify behaviour and their competence to comprehend cognitively the sense of behavioural recommendations. Research has shown that adults can be motivated to adjust their own behaviour in order to protect their children or to be role models for their children. Hence one way to modify children’s behaviour is to address the parents and care persons. Generally education in the family, the social environment and in peer groups, nursery school and at school plays an important role in forming and influencing individual behaviour. The age of the target group has also to be taken into consideration.An important question is how to deal with scientific uncertainties when expressing EMF recommendations for children. Accentuating scientific uncertainties may under certain circumstances raise risk awareness. This can be an intended effect. But the expression of scientific uncertainties can also lead to unintended consequences in parent’s behaviour or even senseless dealing with the respective EMF source.The paper points out relevant aspects of risk communication regarding EMF and children and suggests how recommendations for children might be designed. 相似文献
15.
P Cugini L Di Palma A Ciamei A De Luca G Leone A Pelosio 《Biological Rhythm Research》2013,44(4):468-486
Background – This paper is a concrete example of the problems raised by the need of constructing the time-qualified reference limits (chronodesms) for blood pressure (BP), in order to clinically estimate the hemodynamic parameter in its intrinsic nychtohemeral variability. Methods – Assuming that the noninvasive ambulatory BP monitoring (ABPM) is the eligible technique for this need, it must be realized that the BP chronodems may be of two types, depending on the sample being used for their calculation. The first type may be regarded as “ a priori ” because of the fact that they are derived by a sample of normotensive subjects who are unavoidably recruited via “ causal ” sphygmomanometric measurements and reclassified as normotensive by comparing their ABPM to the fixed reference limits (monodesms) given by WHO (monodiagnosis). Therefore, the “ a priori ” BP chonodesms are by principle derived by subjects who could not be correctly classified as normotensive, their ABPM being not tested versus the time-varying physiological limits. The second type may regarded as “ a posteriori ” in virtue of the fact that they may be constructed on a sample which contemplates the previous subjects who result to be true normotensive via the reassessment of their ABPM versus the “ a priori ” BP chronodesms (chronodiagnosis). The “ a posteriori ” chronodesms may be regarded as biometrically reliable, whether the sample for their construction is additionally constituted by those subjects of the local population who have been erroneously monodiagnosed as hypertensive, while they result to be true normotensive via the chronodiagnostic comparison of their ABPM versus the “ a priori ” BP chronodesms. Results – The biometric reliability of the “ a posteriori ” BP chronodems is demonstrated by the fact that their upper limits are statistically significantly less pronounced due to the fact that they are provided by a sample which has been depured by the falsely monodiagnosed normotensives. Conclusions – The “ a posteriori ” BP upper chronodesms are the time-qualified reference limits which should be used in clinical practice for the chronodiagnosis of hypertension. 相似文献
16.
J. R. Ehleringer I. Ullmann O. L. Lange G. D. Farquhar I. R. Cowan E.-D. Schulze H. Ziegler 《Oecologia》1986,70(2):234-237
Summary Leaves from many misletoe species in Australia strongly resemble those of their hosts. This cryptic mimicry has been hypothesized to be a means of reducing the likelihood of mistletoe herbivory by vertebrates. Leaf Kjeldahl nitrogen contents (a measure of reduced nitrogen and thus amines, amino acids and protein levels) of mistletoes and their hosts were measured on 48 mimetic and nonmimetic host-parasite pairs to evaluate hypotheses concerning the significance of crysis versus noncrypsis. The hypothesis that mistletoes mimicking host leaves should have higher leaf nitrogen levels than their hosts is supported; they may be gaining a selective advantage through crypsis (reduced herbivory). The second hypothesis that mistletoes which do not mimic their hosts should have lower leaf nitrogen levels than their hosts is also supported; they may be gaining a selective advantage through noncrypsis (reduced herbivory resulting from visual advertisement of their reduced nutritional status). 相似文献
17.
The polyamines spermine and spermidine protect proteins from structural and functional damage by AGE precursors: a new role for old molecules? 总被引:1,自引:0,他引:1
Due to the importance of glycation in the genesis of diabetic complications, an intense search for synthetic new antiglycation agents is ongoing. However, a somewhat neglected avenue is the search for endogenous compounds that may inhibit the process and be a source of protodrugs. Based on their ubiquity, their polycationic nature, their essential role in growth, their relatively high concentrations in tissues, and their high concentrations in sperm, we hypothesized that polyamines inhibit glycation and that might be one of their so far elusive functions. In this study we demonstrate a potent antiglycation effect of physiological concentrations of the polyamines spermine and spermidine. We employed two approaches: in the first, we monitored structural changes on histones and ubiquitin in which polyamines inhibit glycation-induced dimer and polymer formation. In the second we monitored functional impairment of catalytic activity of antithrombin III and plasminogen. Protection is afforded against glycation by hexoses, trioses and dicarbonyls AGE precursors and is comparable to those of aminoguanidine and carnosine. 相似文献
18.
Members of the genus Campylobacter are frequently responsible for human enteric disease with occasionally very serious outcomes. Much of this disease burden is thought to arise from consumption of contaminated poultry products. More than 80% of poultry in the UK harbour Campylobacter as a part of their intestinal flora. To address this unacceptably high prevalence, various interventions have been suggested and evaluated. Among these is the novel approach of using Campylobacter-specific bacteriophages, which are natural predators of the pathogen. To optimize their use as therapeutic agents, it is important to have a comprehensive understanding of the bacteriophages that infect Campylobacter, and how they can affect their host bacteria. This review will focus on many aspects of Campylobacter-specific bacteriophages including: their first isolation in the 1960s, their use in bacteriophage typing schemes, their isolation from the different biological sources and genomic characterization. As well as their use as therapeutic agents to reduce Campylobacter in poultry their future potential, including their use in bio-sanitization of food, will be explored. The evolutionary consequences of naturally occurring bacteriophage infection that have come to light through investigations of bacteriophages in the poultry ecosystem will also be discussed. 相似文献
19.
M. Gallichan 《BMJ (Clinical research ed.)》1997,314(7085):964-967
The inappropriate use of self monitoring of glucose is wasteful of NHS resources and can cause psychological harm. Although a few patients find that self monitoring enables them to understand and take control of their diabetes, many people with diabetes are performing inaccurate or unnecessary tests. There is no convincing evidence that self monitoring improves glycaemic control, nor that blood testing is necessarily better than urine testing. It may be appropriate for some patients not to monitor their own glucose but to rely instead on regular laboratory estimations of glycaemic control. Glucose self monitoring should be performed only when it serves an identified purpose. It is widely assumed that glucose self monitoring, preferably of blood glucose concentrations, is desirable or even essential for everyone with diabetes. It is common for patients who have previously tested their urine, or have done no glucose monitoring at home, to be taught to measure their blood glucose when they are admitted to hospital. In the community too, patients are often encouraged to monitor their blood glucose, and newly diagnosed patients of all ages are usually taught to measure their blood glucose concentrations. Self monitoring can sometimes be useful, but evidence is mounting that its indiscriminate use is of questionable value. In 1995, Pounds 42.6 million was spent on home monitoring of glucose in the United Kingdom (Intercontinental Medical Statistics, personal communication). Is this enormous cost justified? Is blood testing necessarily better than urine testing? Is glucose self monitoring always necessary, or is it sometimes a waste of time and money? Are recommendations for self monitoring based on sound evidence? 相似文献
20.
Marine viruses were little studied until 1989, when they were discovered to be extremely abundant in the sea. Virology is
now a growing field of science in coral reef research, largely related to an increase in the frequency of coral bleaching
events and other coral diseases. Because viruses are obligate symbionts, they are generally perceived as parasitic and harmful
to their hosts. However, evidence that viruses confer benefits to their hosts is growing and their role as mutualists is emerging.
Here we review both the detrimental and beneficial aspects of viral infections and argue that as the field of coral virology
expands, in addition to their pathogenicity, the idea that viruses represent functionally beneficial components of the coral
holobiont be considered. 相似文献