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1.
Brain pathology is a perfect application field for nanotechnologies supporting the concept of nanomedicine. It implies the use of nanosized tools for diagnosis and therapy and finally the switch to nanosized disease. A good illustration is the synergistic association of functional neurosurgery to micro/nanotechnologies. The developments around electrostimulation are a good example of the lower invasivity and better therapeutical efficacy that can be achieved. Nanolevel disease detection and therapy dramatically modifies medical philosophy as well as practice. The demonstration of the validity of the concept of nanomedicine has to be done carefully and this period of validation is a precious time to solve ethical problems. Ethical issues include the problem of disease detection in “healthy patients”; the non medical use of nanotechnologies, and the acceptance of what could be a potentially uncontrollable major modification of the human body. All these items are used against nanotechnologies, thus it will be crucial to inform the public about the state of the art in nanomedicine and about the existing regulations. National and European regulations should be adequate for nanomedicine, provided there is progressive integration instead of a conservative attitude blocking experiments and progress. The European research community has a good opportunity to do that.  相似文献   

2.
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   

3.
Measurements of a large series of skulls of the Arctic wolf, Canis lupus arctos . have shown that since 1930 there has been an overall reduction in the size of the skulls, together with widening of the cranium, shortening of the facial region, and reduction in size of the teeth. This suggests that hybridization and subsequent introgression occurred with huskies ( Canis familiaris ) during the 1930s, which is consistent with historical accounts. Since 1950 there has been a reversion in skull morphology to a more 'wolf-like' form, suggesting that hybridization is no longer occurring.
The skull of a wolf/dog hybrid is intermediate in size between the skulls of wolves and huskies but its shape is allometrically dissimilar. Skulls of wolves from the period 1930–50 are moi-e similar to the skull of this hybrid than in the other time periods.
The skull of a male canid from a carcass collected on Ellesmere Island and presented to the Natural History Museum. London, in 1986 was at first thought to be from a wolf/dog hybrid but analyses of the measurements show that it is more likely to be from an Arctic wolf with severe abnormalities to the jaws.  相似文献   

4.
Modern whaling in Britain and the north-east Atlantic Ocean   总被引:1,自引:0,他引:1  
Modern whaling, using an explosive harpoon fired from a steam catcher-boat to kill the fast-swimming rorquals, began from shore whaling stations in northern Norway in the 1860s. It spread to Iceland, the Faeroe Islands and Spitsbergen, before reaching the British Isles in 1903.
Whaling took place from four stations in the Shetland Islands, one in the Outer Hebrides, and two in Ireland, before the First World War. Fin whales were the main species caught but Blue, Humpback, Sei, Right, Sperm and Bottle-nosed whales were also taken. Four stations re-opened in 1920, but from 1923 onwards only two continued to operate and whaling ceased in 1929, though the Hebridean station worked again for two seasons in 1950–1951.
The species composition of catches at the Hebridean and Irish stations was very similar and different from that of the stations in the Shetland Islands where few Blue whales and Right whales were taken. There is evidence that Fin whales were being overfished on the Shetland Islands whaling grounds at an early date, and that Blue whales and Right whales, but not Fin whales, declined in numbers on the Hebridean grounds.
The history of modern whaling in the north-east North Atlantic region as a whole indicates that the stocks of Blue, Humpback and Right whales were not large enough to support continuous whaling on the scale which took place there. The development of whaling since 1945 supports the view that there are separate populations of Fin whales in the region. The numbers of this species have declined on the whaling grounds of the Faeroe Islands and western Norway, and possibly also of north Norway, but not on the Icelandic grounds where there is no evidence of overfishing.  相似文献   

5.
6.
Nanotechnology as an enabling technology for many future medical applications touches on issues such as sensitivity of genetic information, the gap between diagnosis and therapy, health care resources and tensions between holistic and functional medicine. On the other hand nanotechnology will add a new dimension to the bio (human) and non-bio (machine) interface such as brain chips or implants, which eventually might raise new ethical issues specific to NanoMedicine. This requires careful analysis of ethical aspect in view of existing standards and regulations by ethics committees at the European scale. At the same time new nanomedical inventions have to be evaluated for new ethical aspects by Ethical, Legal and Social Aspects — specialists. The most crucial point in this regard is an early proactive analysis of new technological developments to identify and discuss possible issues as soon as possible. This requires a close collaboration and co-learning of technology developers and ethics specialists assisted by communication experts to ensure open and efficient information of the public about ethical aspects (old or new) related to nanomedicine. This co-evolution will ensure a socially and ethically accepted development of innovative diagnostic and therapeutic tools in NanoMedicine.  相似文献   

7.
Going to the roots of the stem cell controversy   总被引:3,自引:0,他引:3  
Holm S 《Bioethics》2002,16(6):493-507
The purpose of this paper is to describe the scientific background to the current ethical and legislative debates about the generation and use of human stem cells, and to give an overview of the ethical issues underlying these debates.
The ethical issues discussed are 1) stem cells and the status of the embryo, 2) women as the sources of ova for stem cell production, 3) the use of ova from other species, 4) slippery slopes towards reproductive cloning, 5) the public presentation of stem cell research and 6) the evaluation of scientific uncertainty and its implications for public policy.  相似文献   

8.
The article aims to illuminate the recent debate in Germany about the legitimacy of circumcision for religious reasons. The aim is both to evaluate the new German law allowing religious circumcision, and to outline the resulting conflict between the surrounding ethical and legal issues. We first elucidate the diversity of legal and medical views on religious circumcision in Germany. Next we examine to what extent invasive and irreversible physical interventions on infant boys unable to given their consent should be carried out for non‐medical reasons. To this end, the potential benefits and harms of circumcision for non‐medical reasons are compared. We argue that circumcision does not provide any benefits for the ‘child as a child’ and poses only risks to boys. We then set out to clarify and analyse political (rather than ethical) justifications of the new circumcision law. We demonstrate through this analysis how the circumcision debate in Germany has been transformed from a legal and ethical problem into a political issue, due at least in part to Germany's unique historical context. Although such a particular political sensibility is entirely comprehensible, it raises particular problems when it comes to framing and responding to medical ethical issues – as in the case of religious circumcision.  相似文献   

9.
Apart from ciliates, there are other protozoans which can form an important element in the herbivorous zooplankton of lakes.
The protozoans discussed in this paper feed on colonial algae. They can greatly reduce the numbers of certain Chlorophyta in Windermere, Esthwaite Water and Blelham Tarn, lakes in the English Lake District.
A very short period, often 7–14 days, can suffice for the destruction of more than 99% of an algal population.
Experiments with a species of Pseudospora showed that it would only ingest one out of six green algal species, although, in nature, Pseudosporae which are morphologically similar to this species have been observed in all these algae.
The importance of such protozoans, and of parasitic fungi, has been underrated or neglected in studies of the quantitative relationships between primary and secondary production in the plankton.  相似文献   

10.
SYNOPSIS. Colpoda elliotti n. sp., found in an enrichment culture from deer droppings, is a small (15–28 by 7.5–17 μ) member of the genus with prominent, rigid, tooth-like processes set between the kineties in the posterior 2/3 of the body. These "teeth" give it a distinctive outline even when viewed at low magnifications. The usual number of kineties is 12; the number of keel notches is 4. Multiplication occurs in reproductive cysts yielding typically 4 tomites. Thick-walled, resting cysts are also formed.
The nuclear apparatus includes a single, crescentic ***micronucleus and a broadly elliptical macronucleus. The latter contains Feulgen-positive material in a few large masses, but no central nucleolus.
The possibility that this species along with other members of the genas is perhaps more closely related to the Hymenostomatida than to the Trichostomatida as now defined is discussed.  相似文献   

11.
The discovery of the genes and cellular pathways that play fundamental roles in several diseases, and the understanding of many diseases at a molecular level due to the advances in the field of genomics, have revolutionized the diagnosis, therapy and prevention of human diseases. Application of genetic testing in numerous medical fields, including pharmacogenomics and oncogenomics, raised numerous ethical questions and introduced legal instruments that are aimed at ensuring the appropriate protection of human research participants. For the effective development of human genomics and translation of novel, validated biomarkers into potentially useful clinical applications in personalized medicine, there is a need for clear ethical standards and principles in all phases of clinical research.  相似文献   

12.
An electron microscopic study has been made of the three respiratory organs of climbing perch. The gill structure is similar to that of the other telcosts but the thickness of the water/blood barrier is much greater, being as great as 20 μm in some specimens. The increased thickness is due to a multilayered epithelium which is thinner (3.5–7 μm) over the marginal channel of the secondary lamellae. The other two main layers, basement membrane and pillar cell flange, are relatively thin (about 1 μm).
The pillar cells have a typical structure, but in certain regions they are contiguous with one another and line well-defined blood channels. Some of the columns of basement membrane material in such regions may be common to adjacent pillar cells.
The air-breathing organs are (a) the lining of the suprabranchial chambers , and (b) the labyrinthine plates attached to the dorsal region of branchial arches. Electron microscopy showed that their structure is well adapted for gas exchange, the air/blood barriers being only 0.12–0.3 μm, comprising an epithelial layer, basement membrane, and thin capillary endothelium. The many parallel blood channels of the respiratory islets of both organs are separated by pillar-like structures which differ from the pillar cells of the secondary lamellae. Thus the hypothesis that the air-breathing organs represent modified gills is not supported by this study.
The fine structure of the non-respiratory region of the air-breathing organs is similar to that of the skin, and includes chemoreceptor-like cells. Evidence concerning the possible homology of pillar cells with plain muscle cells is discussed.  相似文献   

13.
A study of eel catches from Lesina (444 specimens) and Varano lagoons (325 specimens), in southern Adriatic, Italy, was made. Male silver eels in Lesina ranged from 33.4–51.5 cm in length, with a mean of 42.6 cm; from 50–240 g in weight, with a mean of 141 g and were 1.5–6.5 years old with a mean of 2.5 years. The average length of male silver eels in Varano lagoon was 40.5 cm (range 31–48.5 cm); the average weight was 122 g (range 80–220 g)and a mean age of 2.6 years (range 1.5–7.5 years).
The females are bigger, heavier and older than the males with, in Lesina, a mean length of 61 cm (range 50.9–74.3 cm), a mean weight of 438 g (range 240–730 g) and a mean age of 3.4 years (range 1.5–6.5). The average length of Varano female silver eels was 58 cm (range 50.8–72.5 cm), and the average weight was 383 g (range 225–840 g). They were 1.5–7.5 years old, with an average of 3.8 years. Female silver eels were only 20% of the population at Lesina and 10% at Varano.
In comparison with the silver eel populations of the North Adriatic lagoons, the North Sea or the Atlantic Ocean, the silver eels of Lesina and Varano show a greater growth rate, are younger and have a sex ratio in favour of the males.
The water temperature, higher than in other countries, could be an important factor affecting the differences in age and growth rates between Lesina and Varano silver eels and those of other waters.  相似文献   

14.
胡晋红  黄瑾 《生命科学》2012,(11):1250-1257
创新技术的开展和转化医学的注重给医学的发展注入了新的活力,但同时,也带来了一系列社会伦理问题和法律问题。生命医学伦理学的兴起和发展催生了医学研究伦理学分支学科形成,目的在于推进解决涉及人体的医学研究的伦理问题。当前,面临的最突出的伦理问题在于,对医学研究合法性、先进性及伦理性的把握,对医学研究伦理审查必要性的认知,对医学研究方案设计与伦理道德的匹配,对医学研究知情同意的告知,对医学研究风险与受益的平衡。逐步与国际接轨,加强伦理委员会制度建设;提高伦理审查能力建设,形成高水平的伦理审查队伍;学术组织和团体共同努力,推进医学研究伦理学的发展,这将助推医学研究伦理学的发展。  相似文献   

15.
The age, density, distribution and reproductive capacity of Scots pine Pinus sylvestris L. were investigated along an altitudinal gradient through the only undisturbed tree-line remaining in the Cairngorm Mountains. Saplings at 300–410 m a.s.l. were unlikely to develop to reproductive maturity because of repeated browsing by red deer Cervus elaphus L. By contrast, pines were regenerating successfully in scrub at 531–590 m, where the population included individuals of all ages up to 300 yr. Above 590 m, there grew only saplings aged less than 30 yr and these declined in density with increasing altitude up to 730 m.
The climate at 531–590 m was not so severe as to prevent pines from growing to reproductive maturity. However, it may have been severe enough to restrict the activities of large herbivores and so the pine saplings there escaped the heavy browsing suffered by plants at lower altitude. Presumably zones of successfully regenerating pine scrub might occur more widely in the Cairngorms but for a shortage of seed-bearing trees.  相似文献   

16.
Sofaer N  Strech D 《Bioethics》2012,26(6):315-328
There are many ethical decisions in the practice of health research and care, and in the creation of policy and guidelines. We argue that those charged with making such decisions need a new genre of review. The new genre is an application of the systematic review, which was developed over decades to inform medical decision-makers about what the totality of studies that investigate links between smoking and cancer, for example, implies about whether smoking causes cancer. We argue that there is a need for similarly inclusive and rigorous reviews of reason-based bioethics, which uses reasoning to address ethical questions. After presenting a brief history of the systematic review, we reject the only existing model for writing a systematic review of reason-based bioethics, which holds that such a review should address an ethical question. We argue that such a systematic review may mislead decision-makers when a literature is incomplete, or when there are mutually incompatible but individually reasonable answers to the ethical question. Furthermore, such a review can be written without identifying all the reasons given when the ethical questions are discussed, their alleged implications for the ethical question, and the attitudes taken to the reasons. The reviews we propose address instead the empirical question of which reasons have been given when addressing a specified ethical question, and present such detailed information on the reasons. We argue that this information is likely to improve decision-making, both directly and indirectly, and also the academic literature. We explain the limitations of our alternative model for systematic reviews.  相似文献   

17.
My professional lifetime has seen progress in the biomedical sciences that beggars belief. This has lead to astonishing advances in the ability to prevent and treat disease and, in the developed world at least, people live longer and healthier lives than ever before. Paradoxically, this has gone hand in hand with the growth of a vocal and influential anti-science lobby that not only rejects much modern science but is also deeply suspicious of new medical interventions. The prospect of cell therapy in the near or middle future is their current target especially where the use of embryonic stem cells or of cell nuclear transfer techniques is concerned. The prospect of cell therapy is welcomed with enthusiasm by patients with genetic and degenerative diseases who hope to benefit from them. On the other hand the whole idea is regarded as repugnant by the anti-science lobby. While some of this opposition is essentially luddite in nature, there are some more persuasive arguments raised particularly to any research than uses embryonic or foetal materials. These arguments will be examined critically. The moral problems of denying the sick the hope of effective treatments have to be weighed against those seen in the development of such treatments. (This article is closely based on an already published paper. P. Lachmann, Stem cell research: why is it regarded as a threat? An investigation of the economic and ethical arguments made against research with human embryonic stem cells. EMBO Rep. 2 (3) (2001) 165–168.)  相似文献   

18.
M. P. Kahl 《Ibis》1967,109(1):25-32
Hamerkops were studied in Uganda, mainly in the vicinity of Kampala, during January-August 1964. Behavioural observations were made of nest-building pairs, as well as of non-breeding birds.
Locomotion and feeding behaviour are described. Diving take-offs and landings, essential for entering or leaving a completed nest, are sometimes seen in other situations as well. Birds sometimes forage while on the wing, in addition to the more usual method while wading.
The most frequently seen comfort movements and maintenance activities are described. Hamerkops do not excrete onto their legs when over-heated as do the storks. The resting posture of sitting completely down on horizontal branches, which is common among Hamerkops, apparently is not known in any of the herons or storks.
Primarily hostile (Upright and Forward Threat) and primarily sexual ("Yip-purr", Nodding and False Mounting) social displays are described. During False Mounting, birds mount their partners repeatedly without making any attempt at copulation; reverse mountings, in which the other partner assumes the top position, are frequent.
The large, hollow nest and its construction are briefly described. During the 6–7 week building period at one nest, at least 8000 loads of material were added to the structure. Both members have an equal role in nest-building, and generally work independently of each other. They showed no stick-exchange displays as do herons and storks.
When all known aspects of the Hamerkop's behaviour are considered, there appears to be little similarity with either the herons or the storks. In fact, present behavioural evidence does not seem to indicate a particularly close relationship with any other birds so far studied.  相似文献   

19.
L. Schifferli 《Ibis》1973,115(4):549-558
Eggs of known fresh weight were removed from Great Tit nests shortly before hatching and artificially incubated. Four to eight chicks were returned to each nest-box on their hatching day and reared by foster parents. The effect of egg weight on subsequent growth was studied for 81 nestlings (13 broods), 50 of them (8 broods) up to the 17th day.
Hatching success of 275 eggs in the incubator was 67·6% and was not correlated with egg weight.
Egg weight had a significant effect on nestling weight up to the 14th day. Young hatched from lighter eggs grew more slowly at the beginning, but recovered before fledging. Mortality after fledging seemed not to be influenced by egg weight.
Maximum weight (mean 19 g) was attained between the 12th and the 17th day and was positively correlated with egg weight.
The effect of brood-size (small in the experiments) on growth increased significantly with age. The range of egg weight for a nest had a significant effect on growth at the beginning, but a small and not significant effect after the 10th day.
The growth of each brood on any particular day was expressed as a deviation from mean growth. These growth deviations, plotted against date, were similar in all nests and were not correlated with any weather data.
The fledging success of 260 early broods was independent of egg weight, but it was positively correlated with egg weight in 78 late broods (data from 1965–71).
The ecological importance of egg weight at different times of the breeding season is discussed.  相似文献   

20.
The authors co-organized (Snyder and Crooks) and gave a keynote presentation at (Turner) a conference on ethical issues in medical tourism. Medical tourism involves travel across international borders with the intention of receiving medical care. This care is typically paid for out-of-pocket and is motivated by an interest in cost savings and/or avoiding wait times for care in the patient’s home country. This practice raises numerous ethical concerns, including potentially exacerbating health inequities in destination and source countries and disrupting continuity of care for patients. In this report, we synthesize conference presentations and present three lessons from the conference: 1) Medical tourism research has the potential for cross- or inter-disciplinarity but must bridge the gap between researchers trained in ethical theory and scholars unfamiliar with normative frameworks; 2) Medical tourism research must engage with empirical research from a variety of disciplines; and 3) Ethical analyses of medical tourism must incorporate both individual and population-level perspectives. While these lessons are presented in the context of research on medical tourism, we argue that they are applicable in other areas of research where global practices, such as human subject research and health worker migration, are occurring in the face of limited regulatory oversight.  相似文献   

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