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1.
植物RAPD标记的可靠性研究   总被引:71,自引:0,他引:71  
随着RAPD技术应用范围越来越广,RAPD的优缺点也不断反映出来。相左实验结果的出现,对RAPD标记可靠性提出了置疑。本文从重复性、序列同源性和系统学价值三个方面,就RAPD标记的可靠性研究的现状进行了综述。并就怎样提高RAPD标记的可靠性进行了探讨  相似文献   

2.
Zoogeography of Vietnamese primates   总被引:1,自引:0,他引:1  
Based on geographic complementarity of congeneric taxa, the 22 species or well-defined subspecies of primates that inhabit Vietnam may be allocated to nine zoogeographic groups (lorises, two; macaques, three; langurs, three; gibbons, one). Analysis of group distributions reveals two major patterns: (1) four of the six non-macaque groups are essentially restricted to the eastern part of the Indochinese Peninsula, east of the Mekong River; and (2) species and subspecies in seven of the nine groups reach their northern or southern limits of distribution in central Vietnam, at 14–17‡N. The first pattern suggests that the Mekong River has been an important barrier to westward dispersal of nonmacaque primates in continental Southeast Asia. The second pattern suggests that a Zoogeographic barrier formerly extended east and west across Vietnam at ca. 14–17‡N.  相似文献   

3.
Bats account for 30% of mammal diversity in SE Asia and are potential bioindicators of wider biodiversity impacts resulting from habitat loss and climate change.As existing sampling techniques in the region typically fail to record bats that habitually fly in open areas and at higher altitudes,current inventory efforts are less than comprehensive.Acoustic sampling with bat detectors may help to overcome these limitations for insectivorous bats,but has yet to be tested in mainland SE Asia.To do so,we sampled...  相似文献   

4.
Stewart Muir 《Ethnos》2014,79(4):473-495
For many alternative spiritualists, it is axiomatic that indigenous peoples offer a radical alternative to Western materialism and alienation. Such a vision served some of the Australian alternative spiritualists in this research as both an auto-critique of modernity and a profound truth that could serve a range of personal and political projects. In practice, however, faith in this vision had to be reaffirmed in the face of Australian Aboriginal people who did not match the ideal. Maintaining faith in a useable Aboriginal alterity thus required negotiating the tensions between competing constructions of the genuine as either personal authenticity, adherence to tradition, or genealogical essence. Indeed, it was the movement between these different iterations of authenticity that ensured that the search for the real maintained its value as a framework for self-making at the same time as it tied Aboriginal people to a restrictive notion of culture and personhood.  相似文献   

5.
Cyril Schafer 《Ethnos》2016,81(5):759-791
Current thanatology discourse details a new ethos of openness transforming death-related practices, accentuating a shift to personalised rituals, authenticity and expressive grief. Drawing on ethnographic interviews with mourners and funeral professionals, this article explores these putative post-mortem changes and critically assesses the claims and counterclaims concerning funerary arrangements in New Zealand. While underscoring the complexity of mortuary practices, this study explicates the varying notions of authenticity that pervade the funeral discourse. Although funeral professionals emphasised the significance of grief and bereavement processes characterised by a need for honesty and transparency, bereaved participants proffered an alternative interpretation of authenticity that privileged biographical coherence and the need to confer transcendence to the dead. These findings not only emphasise the inadequacies of the aforementioned representations of post-mortem change, but elucidate the context-specific conceptualisations of authenticity and the continuing relationships between the living and the dead in Aotearoa/New Zealand.  相似文献   

6.
This study is a pioneering effort to quantify the materials stocked in the road network of a developing country, Vietnam, and analyze its relationships to the country's recent economic development. National road networks function as capital and infrastructure investments that are necessary catalysts for countries’ development, while requiring the extraction of vast amounts of construction materials for expansion and maintenance causing environmental impacts. However, there has so far been little research on the subject, especially in developing countries. We compile material stock and flow accounts for Vietnam's roads from 2003 to 2013 on the national and provincial levels, finding that approximately 40% of the domestic consumption of construction materials is for expanding and maintaining the road network, and the materials stocked in the road network doubled from 1,321 million metric tons in 2003 to 2,660 million metric tons in 2012. Material stock growth rates closely resembled those of gross domestic product (GDP) in this period, suggesting a codependency of physical infrastructure development and economic development. On the provincial level, our results show local disparities in the stock and its capacity to support the transportation of passengers and freight, especially considering the surging growth of vehicles in urban centers. By showcasing the challenges of conducting a material flow and stock analysis in a developing country, this study not only sheds light on Vietnam's transportation material stock and its policy implications, but also serves as a case study for further work in similar countries.  相似文献   

7.
The expansion of intensive livestock production systems in developing countries has increased the introduction of highly productive exotic breeds facilitating indiscriminate crossbreeding with local breeds. In this study, we set out to investigate the genetic status of the Vietnamese Black H'mong pig breed by evaluating (1) genetic diversity and (2) introgression from exotic breeds. Two exotic breeds, namely Landrace and Yorkshire used for crossbreeding, and the H'mong pig population from Ha Giang (HG) province were investigated using microsatellite markers. Within the province, three phenotypes were observed: a White, a Spotted and a Black phenotype. Genetic differentiation between phenotypes was low (0.5-6.1%). The White phenotypes showed intermediate admixture values between exotic breeds and the Black HG population (0.53), indicating a crossbreed status. Management practices were used to predict the rate of private diversity loss due to exotic gene introgressions. After 60 generations, 100% of Black private alleles will be lost. This loss is accelerated if the admixture rate is increased but can be slowed down if the mortality rate (e.g., recruitment rate) is decreased. Our study showed that a large number of markers are needed for accurately identifying hybrid classes for closely related populations. While our estimate of admixture still seems underestimated, genetic erosion can occur very fast even through indiscriminate crossbreeding.  相似文献   

8.
By employing an intergenerational perspective, this article examines the ways in which memories about the war between Vietnam and the USA are engraved in the social and individual body in a northern Vietnamese rural community. Throughout the 1990s, Vietnam and the USA attempted to improve their postwar relationship. The current atmosphere of coming to terms with a past of war through coexistence and reconciliation fosters ambivalences and ambiguities in young postwar generations. On the one hand, they have to reconcile themselves to the pain and bitterness caused by the war. On the other, they have to bridge the gap between themselves and their parents and grandparents concerning the extent to which they are able to ‘forget the past and look toward the future’, as one national postwar strategy recommends. The article thus highlights the complex ways in which war and postwar generations in local Vietnam attempt to remember and/or forget brutality, sorrow and anger, in order to come to terms with what in Vietnam is referred to as the American War.  相似文献   

9.
10.
This paper examines the concept of biopiracy, which initially emerged to challenge various aspects of the regime for intellectual property rights (IPR) in living organisms, as well as related aspects pertaining to the ownership and apportioning of benefits from 'genetic resources' derived from the world's biodiversity. This paper proposes that we take the allegation of biopiracy seriously due to the impact it has as an intervention which indexes a number of different, yet interrelated, problematizations of biodiversity, biotechnology and IPR. Using the neem tree case as an example, it describes activists' use of the term as one that involves a deliberate simplification of science and IPR. Additionally, it argues that in so doing, biopiracy is positioned as a touchstone that mobilizes actors and problems, and ultimately generates 'solutions' to the very challenges it creates. The paper will also encourage a view of biopiracy claims that does not always treat them simply as claims of theft, or as a misallocation of benefits, but rather as claims that are designed to raise broader questions about the IPR system itself. It concludes by advocating that, in order to properly understand how to address biopiracy, we must be prepared to move beyond the current narrow readings to develop a more complete picture of the term's influence in challenging how, and by whom, the decisions about what is natural and what is invented come to be made.  相似文献   

11.
This study was aimed at assessing the serum levels of vitamin A, copper, zinc, selenium, and iron among adult Vietnamese with and without iron-deficiency anemia. Blood was collected from adult Vietnamese living in the midland of northern Vietnam. One hundred twenty-three subjects in the age range 20–60 yr were included in the study. Anemia, where the concentration of hemoglobin in whole blood is less than 120 g/L in females and 130 g/L in males, was found in 30% (37/123) of the study population. The levels of vitamin A and selenium in the sera of anemic subjects (n=37) were significantly lower than that in nonanemic group (n=86). On the other hand, no significant differences were observed in the concentrations of copper and zinc between the two groups. This study was the first to show serum levels of trace elements in adult Vietnamese, providing useful baseline information for further studies.  相似文献   

12.
13.
A new decenoic acid derivative, gelliodesinic acid, and a naturally new alkaloid, together with three known furanoterpenoids and two known indole alkaloids, were isolated from the MeOH extract of the marine sponge Gelliodes sp. collected in Vietnam. The chemical structures of the isolated compounds were determined by analyses of 1D‐ and 2D‐NMR and MS data and by comparisons of the data with those reported in the literature. The cytotoxicity assay against HeLa, MCF‐7, and A549 cancer cell lines revealed that the three known furanoterpenes exhibited cytotoxic activities with IC50 values ranging from 23.6 to 75.5 μM against the three cell lines, and that 1H‐indole‐3‐carboxylic acid showed cytotoxicity with an IC50 value of 89.2 μM against A549 cancer cell lines.  相似文献   

14.
The investigation of the Vietnamese marine sponge Spongia sp. led to the isolation of three new sesquiterpene phenols, langconols A–C (13), and one new sesquiterpene hydroxyquinone, langcoquinone C (4), together with two known meroterpenoids (5 and 6). Their structures were determined on the basis of spectroscopic analyses and comparisons with published data. Furthermore, the antibacterial assays of the isolates 16 suggested that 4 and 6 had significant antibacterial activities against Bacillus subtilis and Staphylococcus aureus, with MICs ranging from 6.25 to 25.0 µM, while 1 and 3 possessed significant antibacterial activities against B. subtilis with MICs of 12.5 and 25.0 µM, respectively. In contrast, cytotoxic assays of the isolated compounds 16, as well as compounds 715 previously isolated from this sponge, indicated that 1 and the previously reported anti-B. subtilis and anti-S. aureus sesquiterpene phenol 9 lacked cytotoxic activities against three human cancer cell lines (A549, lung cancer; MCF7, breast cancer; HeLa, cervix cancer) and a human normal cell line (WI-38 fibroblast).  相似文献   

15.
Drawing on ethnographic research on Vietnamese migrant workers in Taiwan, I seek to engage with and contribute to the scholarship on migrant networks and social capital. My research demonstrates that migrant networks are central to the social life of Vietnamese workers, offering not only a vital source of material and psychological support but also a platform where relationships are developed, sustained and contested. It reveals both productive and destructive potentials of social capital in situations where the migrant labourer becomes a disenfranchized underclass and their radius of trust is unsettled by physical displacement. Through this research I highlight the complexities and subjectivities in individual experiences of social capital and offer important insights into the various ways in which social networks are reinterpreted and reconfigured at the intersection of mobility, class and ethnicity within the context of Asia.  相似文献   

16.
A comparative investigation on aquatic insect diversity was conducted in a tropical stream in Southeast Asia (the Dak Pri stream in southern Vietnam; stream orders II–V, two sites per stream order) with a reference temperate stream in Northeast Asia (the Gapyeong stream in central Korea) in March 2001 and April 2000, respectively. The numbers of aquatic insect taxa in Dak Pri stream (268 species, mostly undescribed, 230 genera, 91 families, and 9 orders; 110.5 ± 17.1 species per site) were about twice those in Gapyeong stream (133 species, 98 genera, 51 families, and 8 orders; 60.3 ± 8.5 species per site). Coleoptera, Trichoptera, Ephemeroptera, and Diptera were the major aquatic insect orders with high taxonomic richness, and Coleoptera, Odonata, and Hemiptera contributed to the higher degree of aquatic insect diversity in Dak Pri stream. The species diversity indices of Dak Pri stream (4.37 ± 0.19) were higher than those of Gapyeong stream (3.73 ± 0.42), whereas the dominance indices of Dak Pri stream (0.195 ± 0.046) were lower than those of Gapyeong stream (0.346 ± 0.113). Collector-gatherers were predominant in both streams; shredders were more abundant in Dak Pri stream while scrapers were more abundant in Gapyeong stream. Factors affecting the higher degree of aquatic insect diversity in Dak Pri stream are discussed.  相似文献   

17.
Vietnamese coffee beans were investigated for the presence of ochratoxigenic Aspergilli. Ninety-three percent of the coffee samples studied were positive for A. niger. No other ochratoxigenic species were present. HPLC analysis determined that 8.7% of the A. niger strains were positive for ochratoxin A (OA) production. There was no significant difference in the level of contamination or incidence of toxigenic strains in samples that had been rejected by manual sorting and those that were destined for human consumption. No OA-producing fungi were uncovered in a fresh coffee bean sample analysed, suggesting that the OA problem most likely occurs post-harvest.  相似文献   

18.
公立医院产权改革既要考虑到不同省份、地区之间的经济、社会、科技和开放程度的不同,又要考虑到今后区域内经济发展的协调一致性。在欠发达与落后区域,农村公立医院产权改革应先从增量改革开始,从体制外开始,从培育整体医疗市场开始。而民间资本进入医疗市场,可以增加供给,对医疗市场的竞争产生积极影响。此类区域的城市公立医院的产权改革也适宜先从增量开始,鼓励民营医院公平、公正地参与竞争。  相似文献   

19.
While compulsory licensing (CL) is described in the TRIPS agreement as flexibility to protect public health by improving access to medicines in developing countries, a recent literature contends adversely that CL may harm public health. Therefore, this article intends to evaluate the usefulness of CL in the South through the prism of obligations and goals entrusted to patent holders (the effective and non‐abusive exploitation of patents in order to achieve industrial and health developments) and in light of experiences in Thailand and Brazil regarding access to antiretroviral drugs. In this way, it shows that the obligations assigned to patent holders were better served by the recipients of CL and brought significant health and industrial benefits in the two high middle‐income countries. In particular, CL allowed the scaling‐up of free and universal access to antiretroviral drugs by assuring the financial sustainability of these public health programs endangered by monopolistic practices from patent holders.  相似文献   

20.
Since the adoption of the WTO‐TRIPS Agreement in 1994, there has been significant controversy over the impact of pharmaceutical patent protection on the access to medicines in the developing world. In addition to the market exclusivity provided by patents, the pharmaceutical industry has also sought to further extend their monopolies by advocating the need for additional ‘regulatory’ protection for new medicines, known as data exclusivity. Data exclusivity limits the use of clinical trial data that need to be submitted to the regulatory authorities before a new drug can enter the market. For a specified period, generic competitors cannot apply for regulatory approval for equivalent drugs relying on the originator's data. As a consequence, data exclusivity lengthens the monopoly for the original drug, impairing the availability of generic drugs. This article illustrates how the pharmaceutical industry has convinced the US and the EU to impose data exclusivity on their trade partners, many of them developing countries. The key arguments formulated by the pharmaceutical industry in favor of adopting data exclusivity and their underlying ethical assumptions are described in this article, analyzed, and found to be unconvincing. Contrary to industry's arguments, it is unlikely that data exclusivity will promote innovation, especially in developing countries. Moreover, the industry's appeal to a property rights claim over clinical test data and the idea that data exclusivity can prevent the generic competitors from ‘free‐riding’ encounters some important problems: Neither legitimize excluding all others.  相似文献   

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