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81.
21世纪可持续发展面临的七大挑战 总被引:6,自引:1,他引:5
陈国阶 《中国人口.资源与环境》2001,11(1):18-21
可持续发展的过程是不断迎接挑战的过程,21世纪人类将面临人地矛盾的挑战、利用冲突对人类共同目标的挑战、竞争对公平的挑战、发展不平衡对区域均衡目标的挑战、多样性两重性矛盾和突变与灾变的挑战。 相似文献
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Judith Feichtinger 《Local Environment》2013,18(3):229-242
Abstract Local Agenda 21 (LA21), which has its roots in the UN Conference on Environment and Development held in 1992 in Rio de Janeiro, aims at fostering processes of sustainable development on a local level. In this article, we compare the LA21 processes of two cities, Helsingborg in Sweden and Vienna in Austria, to seek insight into the varying implementation approaches of common international political commitments. Our focus of analysis is on the social organisation of the two processes, the way local residents are integrated into LA21 work, and especially the political images of citizens—which we call ‘imagined citizens’—that different actor groups hold. The results of the study illustrate two almost diametrically opposed organisational forms of local sustainability governance, the Swedish process relying on a more expert-led, technocratic model of implementation and the Austrian process strongly building on deliberative forms of citizen participation. 相似文献
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Kevin Spencer 《黑龙江环境通报》2002,22(3):244-246
Over the past three years approximately 12 000 women have been screened in the first trimester through our OSCAR programme, which utilizes fetal NT and maternal serum free β-hCG and PAPP-A. During this time 30 cases of Down syndrome were identified either prenatally or postnatally. Using an established procedure the accuracy of predicted risk for Down syndrome was assessed in a population of 30 cases of Down syndrome and 11 758 unaffected pregnancies. The correlation between predicted risk and prevalence of Down syndrome was very high (r=0.9995). It is concluded that risks produced by the Fetal Medicine Foundation combined risk algorithm agree very closely with Down syndrome prevalence and can be used with confidence when counselling women of their risk. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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The great majority of genetic defects underlying steroid 21-hydroxylase deficiency appear to result from intergenic recombinations between the homologous CYP21 and CYP21P genes. For a minority, novel sporadic point mutations have been detected. De novo mutations in CYP21 have also been reported, but only a few studies have systematically screened their occurrence. We here describe a population-based patient sample in order to estimate the rate of single-family (i.e. sporadic) and de novo germline mutations in the human CYP21 locus. Among 76 Finnish families were observed three single-family mutations and two de novo mutations in CYP21. The rates obtained, ∼5% and ∼2% for novel and de novo mutations, respectively, indicate that they are not rare and that their occurrence should not be ignored in genetic diagnostics of this disorder. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Kevin Spencer Adolfo W. Liao Charas Y. T. Ong Lut Geerts Kypros H. Nicolaides 《黑龙江环境通报》2001,21(6):441-444
Dimeric inhibin A was measured in maternal serum samples from 45 pregnancies affected by trisomy 21 and 493 samples from unaffected pregnancies at 10–14 weeks of gestation. Inhibin A levels in affected pregnancies were compared with levels of free β-hCG and PAPP-A in the same series. In the trisomy 21 group, the median multiple of the median (MoM) inhibin A was not significantly elevated (1.28 vs 1.00) with only 15.5% being above the 95th centile. In contrast, the median MoM free β-hCG was significantly increased (2.05 vs 1.00) with 36% above the 95th centile and PAPP-A was significantly reduced (0.49 vs 1.00) with 42% below the 5th centile. Inhibin A levels in the trisomy 21 group were significantly correlated with gestational age such that median levels rose from 1.04 at 11 weeks to 1.30 at 12 weeks and 1.67 at 13 weeks. These findings suggest that first trimester biochemical screening for trisomy 21, which is currently optimised using maternal serum free β-hCG and PAPP-A and fetal nuchal translucency, will not benefit from the inclusion of inhibin A. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献