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71.
One of the areas of concern raised by cross-border reproductive travel regards the treatment of women who are solicited to provide their ova or surrogacy services to foreign consumers. This is particularly troublesome in the context of developing countries where endemic poverty and low standards for both medical care and informed consent may place these women at risk of exploitation and harm. We explore two contrasting proposals for policy development regarding the industry, both of which seek to promote ethical outcomes and social justice: While one proposal advocates efforts to minimize cross-border demand for female reproductive resources through the pursuit of national self-sufficiency, the other defends cross-border trade as a means for meeting the needs of vulnerable groups. Despite the conflicting objectives of the proposed strategies, the paper identifies common values and points of agreement between the two, including the importance of regulations to safeguard those providing ova or surrogacy services.  相似文献   
72.
强化生物除磷系统的微生物种群及其表征技术   总被引:9,自引:0,他引:9  
详细介绍了强化生物除磷系统(enhanced biological phosphate removal,简称EBPR)中的微生物种群及其表征技术,提出了研究EBPR中微生物种群及其表征技术的发展方向。  相似文献   
73.
We accept that we are responsible for the quality of life of animals in our care. We accept that the activities of man affect all the living things with which we share this planet. But we are slow to realize that as a result we have a duty of care for all living things. That duty extends to the breeding of animals for which we are responsible. When animals are bred by man for a purpose, the aim should be to meet certain goals: to improve the precision with which breeding outcomes can be predicted; to avoid the introduction and advance of characteristics deleterious to well-being; and to manage genetic resources and diversity between and within populations as set out in the Convention on Biological Diversity. These goals are summed up in the phrase precision animal breeding. They should apply whether animals are bred as sources of usable products or services for medical or scientific research, for aesthetic or cultural considerations, or as pets. Modern molecular and quantitative genetics and advances in reproductive physiology provide the tools with which these goals can be met.  相似文献   
74.
The diffusion of innovations model has been used by social scientists for decades to understand the adoption of new agricultural technologies, but its applicability to environmental as opposed to commercial technologies has been the source of much debate. The “classic” model's ability to account for the diffusion of environmental innovations is hampered by its social–psychological roots and voluntarist assumptions. A model more appropriate to the adoption of environmental technologies in a developing country setting should take into account institutional factors, including the mode of interaction between farmers and extension agencies. This paper examines patterns of adoption of a set of environmental farm technologies in the humid tropics of Costa Rica, paying particular attention to the role of a local agricultural engineering university's outreach activities. Our findings indicate that overall patterns of adoption remain low; that farm size is the only structural variable significantly related to adoption; and that of the various extension activities analyzed, farmer attendance at a university meeting or workshop is by far the strongest predictor.  相似文献   
75.
76.
The purpose of this review is to survey current, emerging and predicted future biotechnologies which are impacting, or are likely to impact in the future on the life sciences, with a projection for the coming 20 years. This review is intended to discuss current and future technical strategies, and to explore areas of potential growth during the foreseeable future. Information technology approaches have been employed to gather and collate data. Twelve broad categories of biotechnology have been identified which are currently impacting the life sciences and will continue to do so. In some cases, technology areas are being pushed forward by the requirement to deal with contemporary questions such as the need to address the emergence of anti-microbial resistance. In other cases, the biotechnology application is made feasible by advances in allied fields in biophysics (e.g. biosensing) and biochemistry (e.g. bio-imaging). In all cases, the biotechnologies are underpinned by the rapidly advancing fields of information systems, electronic communications and the World Wide Web together with developments in computing power and the capacity to handle extensive biological data. A rationale and narrative is given for the identification of each technology as a growth area. These technologies have been categorized by major applications, and are discussed further. This review highlights:
  • Biotechnology has far-reaching applications which impinge on every aspect of human existence.

  • The applications of biotechnology are currently wide ranging and will become even more diverse in the future.

  • Access to supercomputing facilities and the ability to manipulate large, complex biological datasets, will significantly enhance knowledge and biotechnological development.

  相似文献   
77.
Allotetraploid oilseed rape (Brassica napus L.) is an agriculturally important crop. Cultivation and breeding of B. napus by humans has resulted in numerous genetically diverse morphotypes with optimized agronomic traits and ecophysiological adaptation. To further understand the genetic basis of diversification and adaptation, we report a draft genome of an Asian semi‐winter oilseed rape cultivar ‘ZS11’ and its comprehensive genomic comparison with the genomes of the winter‐type cultivar ‘Darmor‐bzh’ as well as two progenitors. The integrated BAC‐to‐BAC and whole‐genome shotgun sequencing strategies were effective in the assembly of repetitive regions (especially young long terminal repeats) and resulted in a high‐quality genome assembly of B. napus ‘ZS11’. Within a short evolutionary period (~6700 years ago), semi‐winter‐type ‘ZS11’ and the winter‐type ‘Darmor‐bzh’ maintained highly genomic collinearity. Even so, certain genetic differences were also detected in two morphotypes. Relative to ‘Darmor‐bzh’, both two subgenomes of ‘ZS11’ are closely related to its progenitors, and the ‘ZS11’ genome harbored several specific segmental homoeologous exchanges (HEs). Furthermore, the semi‐winter‐type ‘ZS11’ underwent potential genomic introgressions with B. rapa (Ar). Some of these genetic differences were associated with key agronomic traits. A key gene of A03.FLC3 regulating vernalization‐responsive flowering time in ‘ZS11’ was first experienced HE, and then underwent genomic introgression event with Ar, which potentially has led to genetic differences in controlling vernalization in the semi‐winter types. Our observations improved our understanding of the genetic diversity of different B. napus morphotypes and the cultivation history of semi‐winter oilseed rape in Asia.  相似文献   
78.
赵跃  张宏  夏雪山 《遗传》2015,37(7):635-644
遗传性心肌病(Inherited cardiomyopathy, ICM)是一种常见的遗传性心脏疾病,主要由基因突变所致,是青少年和年轻运动员猝死的最主要原因之一。到目前为止,已经发现约100个基因和其致病有关,这些基因相关的变异位点具有不同的致病机制。随着临床遗传检测在遗传疾病诊断中的应用,对遗传性心肌病的分子遗传学特性及其致病机制进行深入了解,是对该病遗传诊断的关键。下一代半导体测序仪在2010年底由美国Life Technologies公司发布,其以布满微孔的高密度半导体芯片为测序基础,具有快速、经济、灵敏性好、准确率高等特点,已经应用于遗传疾病的突变筛查。文章主要对遗传性心肌病的分子遗传学特性和下一代半导体测序技术在遗传性心肌病遗传检测中的应用以及面临的挑战进行了概括总结,有助于遗传性心肌病的诊断、预防和治疗。  相似文献   
79.
The effects of fluff deposit on benthic biota,NH4 + fluxes and nitrification was studied in thelaboratory using waterlogged and reflooded intertidal sediments fromMarennes-Oléron Bay, France. The fluff deposit was enriched inNH4 + compared to underlying sediments, and promotedchanges of the sediment pH, Eh, C:N ratio, C:chla ratio and the NH4 + efflux tooverlying water. Statistical analysis showed that pore waterNH4 + concentrations were strongly influenced byinteractions between fluff, drying, depth and bioturbation. The fluff depositresulted in anoxia in the top sediments and moved the nitrification zone tosurface layers in fluff. However, the NH4 + enrichment influff did not significantly change actual nitrification rates (range 0–1mmol m–2 d–1) or potentialnitrification rates (range 3–11 mmolNO3 m–2d–1).  相似文献   
80.
真空干燥球孢白僵菌纯孢粉的活孢率、毒力与贮存期   总被引:3,自引:0,他引:3  
采用真空冷冻干燥法 (冻干 )和真空室温干燥法 (抽干 )对球孢白僵菌 (Beauveriabassiana)原菌粉进行了干燥工艺的比较。在固体产孢基质上生产的新鲜纯孢粉 (原菌粉 )含水量达 5 8 65 % ,经 36h冻干或抽干 ,孢子粉的含水量分别降至 3 97%和 4 2 6% ,含孢量分别为 1 2 9× 1 0 1 1 孢子 /g和 1 2 5× 1 0 1 1 孢子 /g ,活孢率分别为 99 0 %和 97 9%。冻干粉和抽干粉之间的活孢率无显著差异 ,但萌发速度不同。原菌粉、抽干粉及冻干粉对桃蚜(Myzuspersicae)在接种后第 7d的LC50 分别为 1 1 5 ,5 89和 2 95× 1 0 4 个孢子 /mL ;在 1 0 6 个孢子 /mL的剂量下对桃蚜的LT50 分别为 3 6d、 4 4d和 3 9d。从生产成本低得多 ,抽干法比冻干法在白僵菌纯孢粉的生产中更有应用前景 ,尽管冻干粉的质量略优于抽干粉。在4℃和 2 0℃下贮存冻干粉并进行为期一年的孢子萌发率和毒力检测。结果显示 ,冻干粉在2 0℃下贮存至 2 5 5d时完全失活而丧失染虫能力 ,而在 4℃下贮存一年后的活孢率仍达90 2 % ,LT50 仅从初始的 3 9d延长至 4 7d。这说明仅通过降低含水量以延长白僵菌孢子粉在常温下的贮存期仍是不可能的。  相似文献   
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