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1.
    
Fadel HE 《Bioethics》2012,26(3):128-135
Stem cell research is very promising. The use of human embryos has been confronted with objections based on ethical and religious positions. The recent production of reprogrammed adult (induced pluripotent) cells does not - in the opinion of scientists - reduce the need to continue human embryonic stem cell research. So the debate continues. Islam always encouraged scientific research, particularly research directed toward finding cures for human disease. Based on the expectation of potential benefits, Islamic teachings permit and support human embryonic stem cell research. The majority of Muslim scholars also support therapeutic cloning. This permissibility is conditional on the use of supernumerary early pre-embryos which are obtained during infertility treatment in vitro fertilization (IVF) clinics. The early pre-embryos are considered in Islamic jurisprudence as worthy of respect but do not have the full sanctity offered to the embryo after implantation in the uterus and especially after ensoulment. In this paper the Islamic positions regarding human embryonic stem cell research and therapeutic cloning are reviewed in some detail, whereas positions in other religious traditions are mentioned only briefly. The status of human embryonic stem cell research and therapeutic cloning in different countries, including the USA and especially in Muslim countries, is discussed.  相似文献   

2.
Stages of the evolvement and development of the major directions of molecular biology in the 1950–1980’s and its prehistory bracketing the 1920–1940’s are considered against the backgrounds of the history of the Soviet science. Short outlines of the lives and activities of the leading scientists who shaped the directions of and provided for success in studying supramolecular cell structures and molecular mechanisms of processes on a cellular level. This essay, which is far from exhaustive in describing the problems that the Soviet scientists have been dealing with, does not cover the studies of the last decade, nor does it evaluate the contributions of the living molecular biologists.  相似文献   

3.
In recent decades, nature conservation policies have increasingly considered the participation of various actors. However, the effectiveness of such efforts is often questionable, and better methods of engaging stakeholders are still being sought. In this paper, we present an analysis of a consultation program conducted in the final stage of site selection for Natura 2000 in Małopolska, a region located in southern Poland. Based on a desk study and qualitative research, we analysed the modes and degrees of participation, the normative foundations of the consultation program, and the goals and expectations that characterise participants. The results are discussed using Unnestall's and Arnstein's typologies of participation, which show the limited success of the participatory process in representing all relevant stakeholders and enabling their actual influence on final decisions. The importance of implementing the EU directives for emerging multilevel governance in the nature conservation sector in Central and Eastern Europe, including Poland, is highlighted. In the context of Poland, the consultation program analysed appeared to be a novel and innovative step forward towards the development of a meaningful participatory approach in this region of Europe.  相似文献   

4.
Current developments in biomedicine are presenting us with difficult ethical decisions and raising complex policy questions about how to regulate these new developments. Particularly vexing for governments have been issues related to human embryo experimentation. Because some of the most promising biomedical developments, such as stem cell research and nuclear somatic transfer, involve such experimentation, several international bodies have drafted documents aimed to provide guidance to governments when developing biomedical science policy. Here I focus on two such documents: the Council of Europe's Convention for the Protection of Human Rights and Dignity of the Human Being and the Additional Protocol to the Convention for the Protection of Human Rights and Dignity of the Human Being. I argue that by using human dignity as a criterion to determine the permissibility of particular human embryo research practices, these documents cannot aid in identifying research that would be contrary to human dignity. Thus, they fail to guide public policy on embryo experimentation. Their use of human dignity as a criterion makes their task of offering guidance unfeasible because the concept as used in these documents is too vague and is applied in contradictory ways. I discuss the main goals of these documents and their claims in relation to human embryo research. I then discuss how they have influenced public policy in several countries. Finally, I show that although these Council of Europe treaties attempt to serve as public policy guides in the area of embryo research, they fail to do so.  相似文献   

5.
In vivo experiments with Sprague-Dawley rats were conducted in order to explore the influence of Cu2+, Zn2+ as well as of the combinations of both on the activity of trypsin. The solutions of the trace elements were given per os, the animals were killed 30 min after the applications, and the activity of trypsin was determined in the juice of the small intestine by usingN α-benzoyl-L-arginine-p-nitroanilide (L-BAPA) as the substrate. The activity of trypsin depends on the concentration of the trace elements. When Cu2+ ions are applied, there is a minimum activity at 10−5 mol Cu2+/L and a maximum at 10−4 mol Cu2+/L. When giving Zn2+ ions, a minimum of trypsin activity is found at 10−5 mol Zn2+/L and a maximum at 5×10−6 mol Zn2+/L. On the whole, the trypsin activity is lower when the Cu2+/Zn2+ combinations are applied compared to the addition of the single trace elements. On principle, a good conformity of the in vivo results was found with in vitro results.  相似文献   

6.
The purpose of the present study was to determine whether zinc and calcium could interact at the tissue level. In the first part of the study, adult rats were injected with ZnCl2 dissolved in a physiological saline solution to determine the effects of Zn on Ca levels in various tissues. In the second part of the study, weaned rats (at day 22 postnatally) were fed a diet supplemented with Zn until day 50 and were then sacrificed. In both instances, blood, brain, heart, liver, and skeletal muscle were taken and analyzed. In the Zn-injected group, the brain, heart, and liver showed no interaction between Zn and Ca. The skeletal muscle, in contrast, showed a decrease in Ca in the homogenate, whereas Zn contents showed a significant increase at the sarcoplasmic reticulum (SR). Likewise, in the Zn-supplemented group, the Zn content of the SR vesicle of the skeletal muscle showed an increase, whereas Ca content of the pellet (14,000 g), which contains cell debris, nucleus, mitochondria, and SR vesicles of this group, showed a decrease. Current findings suggest antagonistic effects between Zn and Ca on this tissue. Zn may play a critical role in cellular function through the alteration of itnracellular distribution of Ca in skeletal muscle.  相似文献   

7.
Iron-deficiency anemia leads directly to both reduced hemoglobin levels and work performance in humans and experimental animals. In an attempt to observe a direct link between work performance and insufficient iron at the cellular level, we produced severe iron deficiency in female weanling Sprague-Dawley rats following five weeks on a low-iron diet. Deficient rats were compared with normal animals to observe major changes in hematological parameters, body weight, and growth of certain organs and tissues. The overall growth of iron-deficient animals was approximately 50% of normal. The ratio of organ weight: body weight increased in heart, liver, spleen, kidney, brain, and soleus muscle in response to iron deficiency. Further, mitochondria from heart and red muscle retained their iron more effectively under the stress of iron deficiency than mitochondria from liver and spleen. Metabolism of iron in normal and depleted tissue was measured using tracer amounts of59Fe administered orally. As expected, there was greater uptake of tracer iron by iron-deficient animals. The major organ of iron accumulation was the spleen, but significant amounts of isotope were also localized in heart and brain. In all muscle tissue examined the59Fe preferentially entered the mitochondria. Enhanced mitochondrial uptake of iron prior to any detectable change in the hemoglobin level in experimental animals may be indicative of nonhemoglobin related biochemical changes and/or decrements in work capacity.  相似文献   

8.
Much has been written about prisoner research and the controversies surrounding prisoners as human subjects. The Institute of Medicine recently released a report addressing some of these issues. This report, which generated further controversy, needs to be fully discussed in the literature and certain aspects are examined in this work. Further, in the body of literature there has been little acknowledgement of the concept of the right of prisoners to be involved in research. This needs to be pursued from an ethical perspective and eventually a legal one. This paper explores that concept and documents some facilities in which a prisoner's right to research has occurred.  相似文献   

9.
    
Cd induced changes of Zn and Cd distribution in the liver and kidneys were studied in relation to Cd metallothionein (MT) synthesis. Wistar male rats were given CdCl2 by sc injection of .8, 1.5, and 3.0 mg Cd/kg three times a week for three weeks. Cd levels of liver and kidneys increased with the increment of Cd dosage and 80–90% of Cd was found in the cytosol. The MT fractions contained 80–89% cytosolic Cd in the liver and 55–75% Cd in the kidneys. Zn concentrations in the liver increased following Cd administration, But Zn in the kidneys showed only slight increase. There was a distinct decrease of Cu concentration in the liver of the 3.0 mg group. In contrast, Cu concentrations in the kidneys increased about three times in the .8 and 1.5 mg Cd groups, but Cu in the 3.0 mg group showed only 1.5 times increase. The changes of these metal concentrations were observed mainly in the cytosol. Non-MT-Cd in the kidneys was maximum in the 1.5 mg group, but the 3.0 mg group showed significant decrease. In parallel with this decrease of Cd, Cu and Zn in the kidneys showed similar decrease. When the kidneys are injured, Zn and Cu appear to leak from this organ.  相似文献   

10.
Streams in mediterranean regions have highly seasonal discharge patterns, with predictable torrential floods and severe droughts. In contrast, discharge is less variable in temperate regions and intermittent flow conditions are uncommon. Hydroclimatic models predict that climate change would increase frequency and severity of floods and droughts across Europe, thus increasing the proportion of streams with mediterranean characteristics in actually temperate areas. Correspondingly, understanding actual ecological differences between mediterranean and temperate streams may help to anticipate large‐scale ecological impacts of climate change. Given that large‐scale factors determine local community composition, we hypothesized that climatic differences between mediterranean and temperate regions should affect the taxonomic and biological trait composition in streams. We assembled the abundance of stream macroinvertebrate genera of 265 sites each from the Mediterranean Basin and from temperate Europe and linked these abundances to published information on 61 categories of 11 biological traits reflecting the potential of resilience from and resistance to disturbances. Although regional taxonomic richness was higher in the mediterranean than in the temperate region, local taxonomic richness and diversity did not significantly differ between regions. Local trait richness and diversity were significantly higher in the mediterranean region. Both local taxonomic and trait‐community composition differed between regions, but the former varied much more than the latter, highlighting that climate change could produce large changes in the taxonomic but rather weak changes in the trait composition. The mediterranean region was characterized by macroinvertebrates with higher dispersion and colonization capabilities, suggesting that species loss in the temperate region, by extinction or northward emigration of taxa, would be compensated for by immigration of southern mediterranean taxa. Thus, climate change would likely have stronger implications for the local conservation of taxa than for the trait composition of stream macroinvertebrate communities.  相似文献   

11.
Ghaly M 《Bioethics》2012,26(3):117-127
When Muslims thought of establishing milk banks, religious reservations were raised. These reservations were based on the concept that women's milk creates 'milk kinship' believed to impede marriage in Islamic Law. This type of kinship is, however, a distinctive phenomenon of Arab tradition and relatively unknown in Western cultures. This article is a pioneer study which fathoms out the contemporary discussions of Muslim scholars on this issue. The main focus here is a religious guideline (fatwa) issued in 1983, referred to in this article as 'one text', by the Egyptian scholar Yūsuf al-Qaradāwī who saw no religious problem in establishing or using these banks. After a number of introductory remarks on the 'Western' phenomenon of milk banks and the 'Islamic' phenomenon of 'milk kinship', this article analyses the fatwa of al-Qaradāwī 'one text' and investigates the 'two contexts' in which this fatwa was discussed, namely, the context of the Muslim world and that of Muslim minorities living in the West. The first context led to rejecting the fatwa and refusing to introduce the milk banking system in the Muslim world. The second context led to accepting this system and thus allowing Muslims living in the West to donate and receive milk from these banks. Besides its relevance to specialists in the fields of Islamic studies, anthropology and medical ethics, this article will also be helpful to physicians and nurses who deal with patients of Islamic background.  相似文献   

12.
13.
    
Long distance nationalism is the dominant perspective in transnational studies. It depicts the diaspora primarily as ‘conflict-makers’ bent on advancing radical view points on homeland socio-political conflicts because of the unique decoupling of action from its consequences. Recent works have shifted the focus away from this negative image and have shown, through in-depth case studies, the constructive dimension of the transnational engagement of the diaspora. Two of these are the crucial role remittance plays in the development process in the country of origin and the peace building role of the diaspora in conflict and post conflict settings. The paper seeks to contribute to the diaspora-peace building literature through a case study of the Ethiopian Muslim diaspora in Europe and North America.  相似文献   

14.
In rats, Mg deficiency caused a moderate hearing loss, measured by means of evoked potentials at 10 and 20 kHz, which was repaired after refeeding a normal diet. Application of 700 mg/kg salicylic acid or injection of 5×100 mg/kg gentamicin also caused a reversible hearing loss in normally fed rats. Treatment of Zn-deficient rats with salicylic acid produced a stronger although reversible hearing loss than in normally fed salicylate-treated rats. Treatment of Mg-deficient rats with gentamicin induced a strong hearing loss that was nearly complete and irreversible in 9 of 25 rats.  相似文献   

15.
Extensive CoE-EU cooperation ensures coherence and complementarities between the principles of the CoE guides which can be regarded as recommendations on best practice, and the technical requirements of the EU directives which set out legally binding requirements. This means that the same standards now exist throughout European continent. Having a common set of standards facilitates cooperation between different healthcare systems, especially in cases of emergencies, and the export–import issues. Adoption of the same quality management and traceability systems helps to minimise the risks and prevent disease transmissions. It reassures patients who undergo treatments outside of their countries. The tissue establishments need to introduce technical and structural changes to adhere to the new regulations which ultimately results in saving and improving of lives of many patients.This and other EU documents on tissues and cells are also available at  相似文献   

16.
Abstract

Interactions of meso-tetra-(4-N-oxyethylpyridyl) porphyrin (TOEPyP(4)), its 3-N analog (TOEPyP(3)) and their Co, Cu, Ni, Zn metallocomplexes with duplex DNA have been investigated by uv/visible absorbance and circular dichrosim spectroscopies. Results reveal the interactions of these complexes with duplex DNA are of two types. (1) External binding of duplex DNA by metalloporphyrins containing Zn and Co, and (2) Binding of duplex DNA both externally and internally (by intercalation) by porphyrins not containing metals, and metalloporphyrins containing Cu and Ni. Results indicate that (4N-oxyethylpyridyl) porphyrins intercalate more preferably in the structure of duplex DNA and have weaker external binding than 3N-porphyrins.  相似文献   

17.
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19.
Studies performed on adult female rats over a period of 10 weeks indicated that the consumption of alcohol (20% v/v) did not appear to disturb the zinc or copper balance, nor did it adversely affect tissue zinc or copper levels, even in zinc-restricted animals. On the contrary, higher plasma zinc levels were consistently observed in animals receiving alcohol together with the experimental diets.  相似文献   

20.
Gutterman  Yitzchak  Gozlan  Sabrina 《Plant and Soil》1998,204(2):223-234
In this study we observed an important interrelationship between the ability of Hordeum spontaneum C. Koch (Poaceae) seeds to germinate after a small rainfall in winter and the dehydration tolerance of young seedlings after one, two or three weeks in dry conditions. In winter, local ecotypes of H. spontaneum started to germinate after only 10 mm of rain, when temperatures were mild, daily evaporation rates were low, and soil water content was 5.8%. In summer, however, germination was not triggered until at least 50 mm of rain was received, at higher temperatures, evaporation rates and soil water content. The point of no return is the earliest stage of germination or after germination at which dehydration will cause the death of the seedling and it depends on the duration in a dry environment, root length before desiccation and on the ecotype. Seedlings were stored in dry conditions for one, two or three weks and then rewetted. A higher percentage of seedlings which had developed roots of 5–20 mm long before desiccation, developed adventitious roots than that of seedlings with roots 1–4 or 40–50 mm long before desiccation. The strategy of regulating germination according to different amounts of rainfall, depending on the season, and seedling drought tolerance, are important survival adaptations in arid and semi-arid regions. These adaptations may enable the young seedlings to overcome drought periods between rainfalls.  相似文献   

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