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Gc subtypes were determined by isoelectrofocusing and immunofixation on 342 blood samples from an Arab Moslem population in Israel. Observed allele frequencies were: Gc1F 0.2120, Gc1S 0.6023, and Gc2 0.1857. Those are similar to formerly reported frequency data for other Middle Eastern populations. A discriminant analysis, performed on data from 35 populations, resulted in a satisfactory classification of population groups related through geographic and racial origin.  相似文献   

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Biomedical research in international settings is undergoing expansive growth and may potentially result in far-reaching benefits, such as direction of research resources toward solving basic health care needs of world populations. However, key ethical concerns surround this expansion and must be carefully considered by international researchers. International research is impacted by differences in language, culture, regulatory structures, financial resources, and possibly ethical standards. Local community leadership involvement in the planning stages of research is imperative. Especially in resource-poor countries, the research agenda must be designed to address local needs and provide local benefit. Capacity strengthening efforts, aimed at improving institutional support for ethical conduct of human subjects research, must continue to be supported by wealthier nations.  相似文献   

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In a typical comparative clinical trial the randomization scheme is fixed at the beginning of the study, and maintained throughout the course of the trial. A number of researchers have championed a randomized trial design referred to as ‘outcome‐adaptive randomization.’ In this type of trial, the likelihood of a patient being enrolled to a particular arm of the study increases or decreases as preliminary information becomes available suggesting that treatment may be superior or inferior. While the design merits of outcome‐adaptive trials have been debated, little attention has been paid to significant ethical concerns that arise in the conduct of such studies. These include loss of equipoise, lack of processes for adequate informed consent, and inequalities inherent in the research design which could lead to perceptions of injustice that may have negative implications for patients and the research enterprise. This article examines the ethical difficulties inherent in outcome‐adaptive trials.  相似文献   

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Here, we present a study of the population genetic architecture and microevolution of the Egyptian fruit bat (Rousettus aegyptiacus) at the environmental margins in the Middle East using mitochondrial sequences and nuclear microsatellites. In contrast to the rather homogenous population structure typical of cave‐dwelling bats in climax tropical ecosystems, a relatively pronounced isolation by distance and population diversification was observed. The evolution of this pattern could be ascribed to the complicated demographic history at higher latitudes related to the range margin fragmentation and complex geomorphology of the studied area. Lineages from East Africa and Arabia show divergent positions. Within the northwestern unit, the most marked pattern of the microsatellite data set is connected with insularity, as demonstrated by the separate status of populations from Saharan oases and Cyprus. These demes also exhibit a reduction in genetic variability, which is presumably connected with founder effects, drift and other potential factors related to island evolution as site‐specific selection. Genetic clustering indicates a semipermeability of the desert barriers in the Sahara and Arabian Peninsula and a corridor role of the Nile Valley. The results emphasize the role of the island environment in restricting the gene flow in megabats, which is also corroborated by biogeographic patterns within the family, and suggests the possibility of nascent island speciation on Cyprus. Demographic analyses suggest that the colonization of the region was connected to the spread of agricultural plants; therefore, the peripatric processes described above might be because of or strengthened by anthropogenic changes in the environment.  相似文献   

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目的:探讨胎儿大脑中动脉(Middle cerebral artery,MCA)与脐动脉(umbilical artery,UmA)和孕妇子宫动脉(uterine artery,UtA)测量诊断胎儿宫内窘迫的临床价值。方法:将我院自2017年1月至2019年1月间收治的孕晚期发生胎儿宫内窘迫的孕妇80例作为研究组,选择同期入院各项指标正常的健康孕妇78例作为对照组,对比观察两组胎儿MCA与UmA和孕妇UtA预测胎儿窘迫的价值及胎儿MCA与UmA与新生儿Apgar评分的相关性。结果:研究组孕妇UtA血流参数脐血流搏动指数(pulsatility index,PI)、脐血流阻力指数(resistance index,RI)和收缩/舒张比(systole/diastole ratios,S/D)指标水平均明显高于对照组,研究组胎儿MCA血流参数PI、S/D均明显低于对照组,研究组患儿UmA的血流参数PI和S/D高于对照组(P<0.05),RI比较差异无统计学意义(P>0.05);研究组新生儿Apgar评分≤7分的比例为40.00%,明显高于对照组15.38%。研究组UmA-PI、UmA-RI和UmA-S/D随着Apgar评分的降低呈现升高的趋势,MCA-PI、MCA-S/D和MCA-S/D随着Apgar评分的降低呈现逐渐减低的趋势。UtA血流参数联合MCA血流参数诊断胎儿宫内窘迫的敏感度为97.50%,特异性为96.25%,均明显高于各项参数单独诊断在的敏感度和特异性(P<0.05)。结论:临床可利用孕晚期孕妇UtA、胎儿UmA和MCA的血流动力学参数改变来预测胎儿宫内窘迫发生的几率,根据胎儿UmA和MCA的血流指标随着Apgar评分的变化趋势,可指导临床早期干预,降低胎儿出生缺陷和死亡率,临床价值较高,可推广使用。  相似文献   

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This article examines the phenomenon of minoritarian regimes in the Middle East, focusing on Bahrain, Syria and Israel/Palestine. It considers, in each, how minority rule was established, the mechanisms through which it is maintained, and the means through which it is legitimated. Although these regimes are not typically analyzed as a category, they have important features in common. In all three, the state's political and security institutions are controlled by members of an ethnic/religious group that is a numerical minority in the country, at the expense of a majority group with a competing claim to indigeneity. While the legal and political mechanisms that these regimes use to restrict access to power vary, they employ similar strategies for legitimating minority rule, presenting democracy as a threat not only to the regime's survival, but also to the security of the group whose interests it claims to represent.  相似文献   

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This article examines issues relating to ethics decision‐making in clinical trials. The overriding concern is to ensure that the well being and the interests of human subjects are adequately safeguarded. In this respect, this article will embark on a critical analysis of the ICH‐GCP Guideline. The purpose of such an undertaking is to highlight areas of concern and the shortcomings of the existing ICH‐GCP Guideline. Particular emphasis is made on how ethics committees perform their duties and responsibilities in line with the principles outlined in the ICH‐GCP Guideline. This article will draw attention to the need for a new approach to addressing the weaknesses of the ICH‐GCP Guideline in its present form.  相似文献   

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Existing ethics guidelines, influential literature and policies on ethical research generally focus on real‐time data collection from humans. They enforce individual rights and liberties, thereby lowering need for aggregate protections. Although dependable, emerging public health research paradigms like research using public health data (RUPD) raise new challenges to their application. Unlike traditional research, RUPD is population‐based, aligned to public health activities, and often reliant on pre‐collected longitudinal data. These characteristics, when considered in relation to the generally lower protective ethico‐legal frameworks of the Global South, including Africa, highlight ethical gaps. Health and demographic surveillance systems are examples of public health programs that accommodate RUPD in these contexts. We set out to explore the perspectives of professionals with a working knowledge of these systems to determine practical ways of appropriating the foundational principles of health research to advance the ever growing opportunities in RUPD. We present their perspectives and in relation to the literature and our ethical analysis, make context relevant recommendations. We further argue for the development of a framework founded on the discussions and recommendations as a minimum base for achieving optimal ethics for optimal RUPD in the Global South.  相似文献   

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The transition from the Lower to the Middle Paleolithic in the Levant is a crucial event in human evolution, since it may involve the arrival of a new human population. In the current study, we present thermoluminescence (TL) dates obtained from 32 burnt flints retrieved from the late Lower Paleolithic (Acheulo-Yabrudian) and Early Middle Paleolithic (Mousterian) layers of Misliya Cave, Mount Carmel, Israel. Early Middle Paleolithic industries rich in Levallois and laminar products were assigned mean ages ranging from ∼250 to ∼160 ka (thousands of years ago), suggesting a production of this industry during MIS 7 and the early part of MIS 6. The mean ages obtained for the samples associated with the Acheulo-Yabrudian (strengthened by an isochron analysis) indicate a production of this cultural complex ∼250 ka ago, at the end of MIS 8. According to the Misliya TL dates, the transition from the Lower to the Middle Paleolithic in the site took place at the limit MIS 8/7 or during the early part of MIS 7. The dates, together with the pronounced differences in lithic technology strongly suggest the arrival of a new population during this period.  相似文献   

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This special issue explores the prospects for what Jacob Mundy calls ‘transformative minority politics’ in the Middle East and North Africa (MENA) region – that is, a form of minority politics that strengthens democratic reform in the region, and that helps deepen a culture of human rights and democratic citizenship. The cases examined in the special issue include the Amazigh in North Africa, the Copts in Egypt, the Kurds in Iraq, the Palestinians in Israel, the ‘minoritarian’ regimes in Syria and Bahrain, and the various ethnic minorities in Iran. In this introduction, we try to situate this debate in a larger historical and international context, identifying some of the factors that might help support a new transformative minority politics in the region, while also emphasizing the factors that have inhibited it in the past, and why they remain powerful.  相似文献   

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The Middle Stone Age (MSA) sediments of Porc-Epic Cave near Dire Dawa, Ethiopia, have produced a large assemblage of archaeofaunal remains dating to the later periods of the Late Pleistocene. As one of the few MSA faunal assemblages from East Africa subject to detailed analysis, it provides rare insight into the foraging behavior of the early modern humans in this region. The MSA fauna include taxa that were not historically present in the area, with the occurrence of reduncines and alcelaphines indicating widespread grasslands and proximity to a perennial source of water. The faunal analysis examined several lines of evidence, including breakage patterns, surface modification, and skeletal-element representation. By incorporating comparisons with multiple actualistic data sets, the analysis of the assemblage demonstrates that, while the influence of carnivores and other biotic agents was evident, the faunal remains were accumulated primarily by hominid activity. The skeletal-element representation at Porc-Epic includes an abundance of high utility bones, in contrast to the predominance of "head-and-foot" elements documented at other MSA and Middle Paleolithic (MP) sites. The MSA occupants of Porc-Epic effectively exploited a wide range of prey with more emphasis on small- and medium-sized mammals.  相似文献   

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Our knowledge of the origins of olive tree domestication in the Middle East and on the processes governing its extension and persistence in different vegetation types from prehistory through antiquity to modern times derives from diverse sources, spanning the biological sciences to the humanities. Nonetheless, it lacks a robust overview that may lead to floating interpretations. This is especially true in the Middle East, considered as the cradle of agriculture, and where the evolutionary history of this emblematic tree is intertwined with that of civilizations. Olive fruit, oil and wood have been, since Prehistoric times, characteristic products of the lands bordering the Mediterranean Sea. In the domestic economy of these countries, the olive tree gradually became a traditional tree crop since the first oil extraction, through the emergence of regional commerce that accompanied the rise and fall of early Near-Middle Eastern urbanism, until the development of modern trade, with an oil production estimated at circa 3000000 tons per year. The rising importance of the olive tree in human life has turned the tree into an endless source of fascination in the Aegean and Eastern Mediterranean, a symbol and a sacred tree, widely cited in the Bibles, the Koran, and in ancient literature. Here we argue that advances in radiocarbon chronology, palaeobotany, genetics, and archaeology-history have profoundly refined the history of olive trees in the Middle East. This review shows that the heartland of primary olive domestication must be enlarged to the Levant and not only focus on the Jordan Valley. The domestication of the olive tree is a long and ongoing process, linked to the early production of oil and the development of the olive trade. We also suggest that the olive tree became a particular icon, a sacred tree, during the Biblical period in the Levant.  相似文献   

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Tulips: An Ornamental Crop in the Andalusian Middle Ages. The authors are working on the project “Crop Flora of al-Andalus,” which aims to recover the crop diversity of the Middle Ages in western Europe during the Islamic period. The documental sources of this study are all the agricultural treatises written in this territory and culture between the 10th and 14th centuries. Al-Andalus was the territory occupied by Islam between the 8th and 15th centuries, varying over time on varying regions on the Iberian Peninsula. In this period, a genuine agricultural revolution took place, as well as the incorporation into the Western world of many Eastern agricultural species. When we focused on the study of ornamental species used in gardens, courtyards, and houses, tulips could be identified in several texts, the main one being the ‘Umda, a botanical work written at the end of the 11th century or beginning of the 12th, probably by the agronomist Abu l-Jayr. Tulips are mentioned in this text 500 years before the first known references to their introduction into Europe, traditionally asserted to be from the Ottoman Empire to Holland via Austria, always in the 16th century. Thus the route of these ornamental bulbs in their passage from East to West must be modified.  相似文献   

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New discoveries show that very small theropod tracks (cf. Wildeichnus) are abundant in the upper part of the Moab Member, recently assigned to the Curtis Formation (formerly considered part of the Entrada Formation) in the Mid-?Late Jurassic of eastern Utah. The tracks represent a distinct small-theropod ichnofacies associated with eolian dune deposits that is easily differentiated from the water-lain beds of the overlying Megalosauripus-Therangospodus ichnofacies, which comprises the single-surface Moab megatracksite. Pterosaur track assemblages, representing the Pteriachnus ichnofacies, are found a few meters above the megatracksite surface in the upper tongue of the Summerville Formation.

The small theropod ichnofacies is reminiscent of other early Mesozoic dune facies ichnofaunas from the Wingate and Navajo formations (Late Triassic and Early Jurassic) where small theropod tracks occur in association with other small tetrapod footprints. All such examples evidently represent a recurrent dune facies ecosystem dominated by diminutive vertebrates. Because the small theropod ichnofacies is one of three ichnofacies found in a thin stratigraphic sequence (<20 m) that contains no body fossils, it is clear that vertebrate tracks play an important role in providing insight into the paleoecology of units previously considered devoid of any useful fossil evidence. The three successive ichnofacies represent a transgressive transition from sand dunes, through sandy shoreline to shallow marine environments, each with its quite distinct vertebrate fauna.  相似文献   

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The Campanian Ignimbrite (CI) eruption, dated by 40Ar/39Ar and various stratigraphic methods to ca. 39,000 cal BP, generated a massive ash plume from its source in southern Italy across Southeastern and Eastern Europe. At the Kostenki-Borshchevo open-air sites on the Middle Don River in Russia, Upper Paleolithic artifact assemblages are buried below, within, and above the CI tephra (which is redeposited by slope action at most sites) on the second terrace. Luminescence and radiocarbon dating, paleomagnetism, and soil and pollen stratigraphy provide further basis for correlation with the Greenland and North Atlantic climate stratigraphy. The oldest Upper Paleolithic occupation layers at Kostenki-Borshchevo may be broadly correlated with warm intervals that preceded the CI event and Heinrich Event 4 (HE4; Greenland Interstadial: GI 12-GI 9) dating to ca. 45,000-41,000 cal BP. These layers contain an industry not currently recognized in other parts of Europe. Early Upper Paleolithic layers above the CI tephra are correlated with HE4 and warm intervals that occurred during 38,000-30,000 cal BP (GI 8-GI 5), and include an assemblage that is assigned to the Aurigancian industry, associated with skeletal remains of modern humans.  相似文献   

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