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1.
FROM THE EDITORS     
Caplan AL 《Bioethics》1987,1(2):119-140
The shortage of organs and tissues for transplantation in infants is particularly severe. Caplan considers the moral and public policy implications of utilizing abortuses and brain dead or anencephalic infants as donors. Arguments favoring their use include the potential benefits for research, benefits to existing infants born with fatal conditions, the ethical cost of relying on primates as sources of organs, and the providing of solace to grieving parents. Arguments against their use include the potential for coercion or conflict of interest in parental decisions about donation, the possibility that abortion may be encouraged, the fact that brain death is difficult to diagnose in infants while organ procurement from anencephalics may be considered murder, and the charge that an increase in infant transplants would be too costly. Caplan concludes that the arguments for using abortuses, anencephalics, and brain dead infants as organ and tissue donors outweigh the arguments against.  相似文献   

2.
From the editors     
Kuhse H  Singer P 《Bioethics》1990,4(3):iii-iii
Kuhse and Singer, the editors of this special issue of Bioethics, introduce seven articles on conflicting concepts, public policies, and standards for the determination of cardiorespiratory and brain death and the relationship of brain death to the beginning of "brain life" and to organ donation, especially from anencephalic infants. The articles are "Consciousness, the brain and what matters," by Grant Gillett; "Brain death and the anencephalic newborn," by Robert D. Truog and John C. Fletcher; "Brain death and brain life: rethinking the connection," by Jocelyn Downie; "A plea for the heart," by Martyn Evans; "The importance of knowledge and trust in the definition of death," by Bo Andreassen Rix; "Death, democracy and public ethical choice," by Reid Cushman and Soren Holm; and "Misunderstanding death on a respirator," by Tom Tomlinson.  相似文献   

3.
Melo H  Brandao C  Rego G  Nunes R 《Bioethics》2001,15(5-6):427-442
In most western countries, there is a 'human organ shortage' with waiting lists for the performance of transplantation. In a recent report of the UNOS Ethics Committee it is stated that there are approximately 31,000 potential recipients on waiting lists, but only one fourth of potential donors gave their specific consent.
Xenotransplantation – defined as the transplantation of animal cells, tissues or organs into human beings – is associated with particular ethical dilemmas, namely the problems of efficiency and safety of this medical procedure. The objective of this study is to analyse the ethical dilemmas in xenotransplantation with the background of a personal view of moral life. Also, xenotransplantation will be evaluated as far as the legal regulation of transplantation is concerned. In particular, we will consider patients rights in accordance with existing laws on organ and tissue transplantation, animal research and clinical trials.  相似文献   

4.
Irradiation of the human body by external or internal sources leads mostly to a simultaneous exposure of several organs. However, so far no clear and consistent recommendations for the combination of organ doses and the assessment of an exposure limit under such irradiation conditions are available. Following a proposal described in ICRP-publication 14 one possible concept for the combination of organ doses is discussed in this paper. This concept is based on the assumption that at low doses the total radiation detriment to the exposed person is given by the sum of radiation detriments to the single organs. Taking into account a linear dose-risk relationship, the sum of weighted organ doses leads to the definition of an "Effective Dose". The applicability and consequences of this "Effective Dose Concept" are discussed especially with regard to the assessment of the maximum permissible intake of radionuclides into the human body and the combination of external and internal exposure.  相似文献   

5.
Iodine and thyroglobulin concentrations, as well as iodine, T3, T4 and sialic acid contents of thyroglobulin, were measured in thyroid glands collected postmortem from 42 human premature or term newborns and infants. Three groups were considered: very preterm newborns (24-32 postmenstrual weeks, < 5 days postnatal life), preterm and term newborns (34-41 postmenstrual weeks, < 5 days postnatal life) and infants (born at term, postnatal age 1-8 months). Five very preterm and seven preterm newborns received a daily dose of 10 microg/kg L-T4 for at least 3 days. Thyroid weight and sialic acid content of thyroglobulin progressed with maturation. Intrathyroidal concentrations of iodine and thyroglobulin did not increase significantly before the 42nd week of postmenstrual age. The level of thyroglobulin iodination increased during the postnatal life, except in the very preterm neonates. T4 and T3 content of thyroglobulin was directly proportional to its degree of iodination and positively related to its sialic acid content. L-T4 treatment of preterm newborns increased thyroglobulin iodination and T4-T3 content, without increasing thyroglobulin concentration in the thyroid. It was concluded that the storage of thyroglobulin and iodine in the thyroid develops around term birth. This, associated with the resulting rapid theoretical turnover of the intrathyroidal pool of T4 in Tg, could be an important factor of increased risk of neonatal hypothyroxinemia in the premature infants. The L-T4 treatment of preterm newborns does not accelerate the maturational process of the thyroid gland.  相似文献   

6.
Whereas the infant gut microbiome is the subject of intense study, relatively little is known regarding the nares microbiome in newborns and during early life. This study aimed to survey the typical composition and diversity of human anterior nare microflora for developing infants over time, and to explore how these correlate to their primary caregivers. Single nare swabs were collected at five time points over a one-year period for each subject from infant-caregiver pairs. Our study comprised of 50 infants (recruited at 2 weeks, post delivery) and their 50 primary caregivers. Applying the chaperonin-60 (cpn60) universal target (UT) amplicon as our molecular barcoding marker to census survey the microbial communities, we longitudinally surveyed infant nares microbiota at 5 time points over the course of the first year of life. The inter- and intra-subject diversity was catalogued and compared, both longitudinally and relative to their adult primary caregivers. Although within-subject variability over time and inter-subject variability were both observed, the assessment detected only one or two predominant genera for individual infant samples, belonging mainly to phyla Actinobacteria, Firmicutes, and Proteobacteria. Consistent with previously observed microbial population dynamics in other body sites, the diversity of nares microflora increased over the first year of life and infants showed differential operational taxonomic units (OTUs) relative to their matched primary caregiver. The collected evidence also support that both temporal and seasonal changes occur with respect to carriage of potentially pathogenic bacteria (PPBs), which may influence host predisposition to infection. This pilot study surveying paired infant/caregiver nare microbiomes provides novel longitudinal diversity information that is pertinent to better understanding nare microbiome development in infants.  相似文献   

7.
C-type natriuretic peptide (CNP) is assuming increasing importance in cardiovascular disease, and in adults its plasma levels are related to clinical and functional disease severity. Data are scarce regarding the reference values for CNP in infancy. Aim of this study was to assess the reference intervals for CNP in human healthy newborns and infants. Plasma CNP was measured in 121 healthy children divided into: 41 newborns (age 0-3 days), 24 newborns (4-30 days), 22 infants (1-12 months) and 32 children (1-12 years). A group of 32 healthy adult subjects (age 64 ± 1 years) was also studied. CNP was measured by a specific radioimmunoassay. Between- and within-assay variability resulted ≤ 30 and 20%, respectively and analytical sensitivity 0.77 ± 0.05 pg/tube. Plasma CNP resulted significantly higher in children than in adult subjects (13.6 ± 1.2 pg/ml vs. 7.4 ± 1.0 pg/ml, p=0.030). When the results were analyzed as a function of the age the reference intervals for plasma CNP resulted: 11.6 ± 2.1 pg/ml for newborns (0-3 days), 16.4 ± 3.7 pg/ml for newborns (4-30 days), 15.4 ± 2.7 pg/ml for infants (1-12 months), 13.6 ± 2.3 pg/ml for children (1-12 years) [p=0.01 newborns (4-30 days) vs. adults; p=0.03 infants (1-12 months) vs. adults]. CNP showed the highest concentrations after 12h of life with a peak between 4 and 5 days of life and with a progressive decline afterwards. According to these data at least five different reference intervals for CNP determinations should be used. These observations may be helpful for future clinical application of CNP in human children.  相似文献   

8.
Gangliosides from histopathologically-defined human cerebrum-resembling remnant and cerebellum from 37 and 30 gestational week-old anencephaluses were identified using mass spectrometry and high performance thin layer chromatography combined with immunochemical analysis in comparison to respective normal newborn/fetal and adult brain regions. A novel strategy of nano-electrospray ionization quadrupole time-of-flight tandem MS has been developed for identification of ganglioside components in complex mixtures. By morphoanatomical and histological investigation the anencephalic cerebral remnant was found to be aberrant, while the anencephalic cerebellum was defined as normal. Total ganglioside concentrations in the anencephalic cerebral remnant and the cerebellum were 34% and 13% lower in relation to the age-matched controls. In the cerebral remnant, GD3, GM2 and GT1b were elevated, while GD1a was decreased in the anencephalic cerebral remnant, but enriched in anencephalic cerebellum. GQ1b was reduced in both anencephalic regions. Gg4Cer, GM1b and GD1alpha, members of the alpha-series biosynthetic pathway, and neolacto-series gangliosides were found to be present in anencephalic, as well as in normal, fetal and adult brain tissues, indicating the occurrence of these biosynthetic pathways in human brain. In both cerebral and cerebellar anencephalic tissues, GM1b, GD1alpha, nLM1 and nLD1 were expressed at a higher rate in relation to normal tissue. It can be demonstrated that the anencephalic cerebral remnant, as a primitive brain structure, represents a naturally-occurring model to study the ganglioside involvement in induction of aberrant brain development.  相似文献   

9.
Since 1960, clinical organ transplantation has evolved from an experimental procedure to highly successful ‘routine’, but as technical advances have extended eligibility to more victims of end-stage organ disease, the supply of donor organs has lagged behind. Urgency of need, probability of success and ability to pay are often used to limit waiting lists; without these, as many as 124 000 transplants per year could be performed in the USA alone. Although the supply of organs from human donors may well be assisted in future by increased public education and changes in donor laws, it is unlikely that the need for organs will ever be met by generosity and calamity alone — hence the enthusiasm for other sources of organs.  相似文献   

10.
The International Institute for the Advancement of Medicine (IIAM) provides non-transplantable organs and tissues for medical and scientific research, education, and drug & device development. The benefits of using human organs and tissues for research are vast, and donating for research provides donor families with a valuable option if their loved one??s organs are unsuitable for transplantation. The use of these organs and tissues enables the faster development of more efficacious drugs with improved safety profiles, and enhanced understanding of basic disease processes that directly affect humans. Human organs and tissues offer unique advantages over the use of animal organs and tissues as it is human diseases and conditions which we seek to treat, and so logically the results can be more directly applied. The added advantage of accessing non-transplantable, human organs is that they are in superb condition, and so experiments can be conducted in a very physiologically-relevant system. Although the US is a sizeable country with a large population and individual regulations governing human tissue collection and usage for each of the 50 states comprising the US this article will discuss how IIAM succeeds in immediately linking organ donors and qualified researchers, ultimately to the great benefit of patients.  相似文献   

11.
12.
With the emergence of organ donation and donation technology, the previous indivisibility of the human body becomes divisible, and different human organs form a new life subject. With reference to specific case studies in China, a new life, consisting of donated organs from different bodies by donation, can be called “donated life.” Donated life is a win-win action between altruism and egoism, that is, to save the lives of others and to regenerate the organs of donors or their relatives. Due to the emergence of this kind of life, traditional social ethics theories based on the marriage-related family find it difficult to difficult to explain the new realities. Thus, new thinking about social ethics is necessary.  相似文献   

13.
Urinary excretion levels of N-methylhistidine derivatives and N-methylhistidine/creatinine ratios were studied in a group of 20 small for date newborns, 10 premature infants and 8 normal infants, at birth and at one week of life. All infants were fed with an adapted milk formula supplying 2.8 g protein/kg body weight. 1-methyl and 3-methylhistidine urinary excretion were increased in all groups of infants from birth to the 7th day of life. Creatinine and N-methyl derivatives/creatinine ratios were also significantly increased at one week of life. The two ratios showed a higher level in small for date and premature infants than in normal infants at birth which continued relatively increased at one week of life. 3-methyl-histidine/creatinine ratio appears as a useful indicator of the turnover rate of muscular proteins in low-birth-weight infants.  相似文献   

14.
Growth failure in the Down syndrome is common postnatally, but is thought to be less consistent in fetuses and newborns. We describe the growth of individual organs in 53 second-trimester abortuses with trisomy 21 and compare the organ weights to organ weights from 432 spontaneously aborted, but otherwise normal control specimens. Using multiple regression analysis, we found body weight to be the most significant predictor of all organ weights in normal fetuses; therefore, this variable was used to generate the regression lines to which the organ weights of trisomic specimens were compared. All trisomic fetal organs were found to be small, with an abnormal karyotype being a significant predictor of low organ weight. However, the effect on individual organs was variable, with some organs differing only minimally from the controls. Placental weights were not affected by fetal trisomy. This study demonstrates the presence of well-established, although variably severe, growth retardation in second-trimester fetuses with Down syndrome.  相似文献   

15.
Derived aspects of our human life history, such as short interbirth intervals and altricial newborns, have been attributed to male provisioning of nutrient-rich meat within monogamous relationships. However, many primatologists and anthropologists have questioned the relative importance of pair-bonding and biparental care, pointing to evidence that cooperative breeding better characterizes human reproductive and child-care relationships. We present a mathematical model with empirically-informed parameter ranges showing that natural selection favors cooperation among mothers over a wide range of conditions. In contrast, our analysis provides a far more narrow range of support for selection favoring male coalition-based monogamy over more promiscuous independent males, suggesting that provisioning within monogamous relationships may fall short of explaining the evolution of Homo life history. Rather, broader cooperative networks within and between the sexes provide the primary basis for our unique life history.  相似文献   

16.
The plasma levels of 8 steroid hormones were studied longitudinally in 20 newborns affected with either 21-hydroxylase (21-OH), 11-hydroxylase (11-OH) or 3 beta-hydroxysteroid deshydrogenase (3 beta-ol) deficiencies during the first month of life. Comparison was also made between the patterns observed according to age at first examination (n = 13 before 8 days of age) and the type of the enzymatic block. The most striking findings were the variability in hormone levels and/or evolution with age and the difficulties in making a definite positive or etiological diagnosis at first examination. In some newborns with untreated 21-OH deficiency, 17 alpha-hydroxyprogesterone levels may start off within the normal range or not so far above it. Also, levels of unconjugated dehydroepiandrosterone and other delta 5 steroids may be so high during the first week of life in all 3 forms that an erroneous diagnosis of 3 beta-ol deficiency could easily be considered. In several cases the etiological diagnosis was only ascertained by multiple steroid determination and/or dynamic tests. These discrepancies were not found in infants studied later on in life. It thus appears that a peculiar steroid pattern is observed in the immediate postnatal period in babies with various enzyme defects, which might be related to the morphological changes occurring in the adrenal cortex at this age.  相似文献   

17.
18.
Paukner A  Ferrari PF  Suomi SJ 《PloS one》2011,6(12):e28848
Human infants are capable of accurately matching facial gestures of an experimenter within a few hours after birth, a phenomenon called neonatal imitation. Recent studies have suggested that rather than being a simple reflexive-like behavior, infants exert active control over imitative responses and 'provoke' previously imitated gestures even after a delay of up to 24 h. Delayed imitation is regarded as the hallmark of a sophisticated capacity to control and flexibly engage in affective communication and has been described as an indicator of innate protoconversational readiness. However, we are not the only primates to exhibit neonatal imitation, and delayed imitation abilities may not be uniquely human. Here we report that 1-week-old infant rhesus macaques (Macaca mulatta) who show immediate imitation of a lipsmacking gesture also show delayed imitation of lipsmacking, facilitated by a tendency to refrain from lipsmacking toward a still face during baseline measurements. Individual differences in delayed imitation suggest that differentially matured cortical mechanisms may be involved, allowing some newborns macaques to actively participate in communicative exchanges from birth. Macaque infants are endowed with basic social competencies of intersubjective communication that indicate cognitive and emotional commonality between humans and macaques, which may have evolved to nurture an affective mother-infant relationship in primates.  相似文献   

19.
Phototherapy is commonly used in the treatment of hyperbilirubinemia in newborns. No serious side effects related to phototherapy have been observed, but concerns regarding its potential to damage DNA have been expressed, based on animal or cell-culture studies. The aim of this study was to investigate, in neonates with hyperbilirubinemia, the possible relation between phototherapy and DNA damage. The study included 33 full-term newborns with non-physiological jaundice and 14 healthy newborns with physiological jaundice as controls. Phototherapy was performed with an array of six fluorescent lamps producing radiation with wavelengths of 480-520 nm at 12 microW/cm(2)/nm. DNA damage in lymphocytes was determined by use of the alkaline comet assay. The DNA damage increased significantly with the duration of phototherapy, as shown by measurements at 24, 48, and 72 h (P<0.001). These findings indicate that phototherapy, widely used in neonatology units, increases DNA damage in newborns. It remains to be seen whether the genotoxic effect observed in the present study can cause any long-term health effect in phototherapy-treated infants in later life.  相似文献   

20.
Current medical transplantation confronts major problems such as the shortage of donors and geographical restrictions that inhibit efficient utilization of finite donor organs within their storage lives. To overcome these issues, expanding organ preservation time has become a major concern. We investigated whether a strategy which best preserves organ grafts can be achieved by the use of a newly developed refrigerating chamber, which is capable of establishing a supercooled and unfrozen state stably by generating an electrostatic field in its inside. When adult rat organs such as heart, liver, and kidneys were stored in the supercooled conditions, the levels of major biochemical markers leaked from the preserved organs were significantly lower than in the ordinary hypothermic storage. No apparent tissue damages were observed histologically after the supercooled preservation. Our results suggest that the use of this supercooling refrigerator improves organ preservation and may provide an innovative technique for human organ transplantation.  相似文献   

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