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181.
为了以可持续方式确保世界食品保障,必须解决许多与安全性、流通及其它因素有关的问题.然而,不应当忘记,生产足够的食品是至关重要的.与食品有关的世界贸易问题(包括涉及生物技术应用的问题)应当成为各国之间和各公司之间不断对话的课题.以共同商定的风险评价程序为基础的、国际和谐的质量和安全性标准,是此类讨论的最合理依据.  相似文献   
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Traditionally, in Spain bullfighting represents an ancient and well-respected tradition and a combined brand of sport, art and national identity. However, bullfighting has received considerable criticism from various segments of society, with the concomitant rise of the animal rights movement. The paper reports a survey of the Spanish citizens using a face-to-face survey during January 2016 with a total sample of 2522 citizens (1256 men and 1266 women). The survey asked about degree of liking and approving; culture, art and national identity; socio-economic aspects; emotional perception and animal welfare. The hypothesis proposed that the perception of bullfights may be affected by gender, age, occupation, origin and nationality of the persons surveyed. The hypothesis was confirmed. The majority of citizens surveyed do not like bullfights and great majorities do not attend or watch such events. Two extreme clusters were described: one representing favorable attitude towards bullfighting and other against bullfighting. The proportion of indifferent persons was important. Women and young people showed a more favorable attitude towards animal welfare issues associated with these events. Rural people were more accepting bullfights than urban people. Students were more anti-bullfight than those in other occupations. Additionally, technical economic factors made people favor more bullfights. The growth of claim against bullfights establishes an element of a far more multifaceted phenomenon that animal cruelty per se and support of a new paradigm called social change in countries as Spain.  相似文献   
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A polymerase chain reaction (PCR) assay has been developed for the detection of Toxoplasma gondii. The target sequence (88 bp) is part of a rDNA repetitive gene. A signal can be observed with only one parasite. It is directly and rapidly detected by electrophoresis and ethidium bromide staining. We report a prospective study of 80 documented cases of toxoplasmic seroconversions during pregnancy. The PCR assay of the amniotic fluids was compared with the current standard methods for diagnosis of fetal infection. Seventy specimens gave no PCR signal, and were negative according to prenatal tests and postnatal examinations. The presence of T. gondii was detected in ten specimens by PCR analysis. Four were confirmed by isolation of the parasite from the amniotic fluid; four by biological study of the fetal blood. For the remaining two, infection was diagnosed after birth. Together with ultrasonographic and biological data, this technique permits prenatal diagnosis within 1 day.  相似文献   
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ABSTRACT: Federal planners, in proposing the massive main stem Missouri River water developments in Montana and North Dakota, promised economic and social benefits to the local residents. Five main stem dams, Fort Peck, Garrison, Oahe, Big Bend and Fort Randall, were evaluated for community and rural development effectiveness. Thirty-seven development factors were examined and improvements noted. Only small differences were noted between areas with water developments and the control area. Further analysis revealed that water development benefits moved downstream and to existing urban areas. The Missouri River's rural areas and small communities were not developed significantly by the water projects. Several problems associated with water development policy were illustrated by the study. Cultural differences between planners and the population impacted were ignored. Second, the allocation of social costs was not considered and related to this, serious geographic maldistribution of benefits and costs resulted. The differences between pre-development promises and development performance was dramatic. While the large dams remain as landmarks to engineering prowess, the projects need to be evaluated for their success in meeting humanistic development objectives. Major redevelopment may be warranted by such an ex-post evaluation.  相似文献   
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Prenatal diagnosis of fetal trisomy 21 is usually performed by cytogenetic analysis. This requires lengthy laboratory procedures, high costs and is unsuitable for large-scale screening of pregnant women. Today, trisomy 21 can be rapidly diagnosed within 24 h by molecular analysis of uncultured fetal cells using the semi-quantification of fluorescent PCR products from short tandem repeat (STR) polymorphic markers. The aim of our study was to test a chromosome quantification method on the basis of the analysis of fluorescent PCR products derived from non-polymorphic target genes. Co-amplification of a portion of DSCR1 (Down syndrome Critical Region 1) and the reference gene, CFTR (cystic fibrosis transmembrane regulator) enabled molecular detection of trisomy 21. Our method was successfully tested on a total of 154 amniotic fluids in a blind prospective study. Calculation of the DSCR1/CFTR ratio allowed us to distinguish between 152 normal amniotic fluids (mean ratio 0.99) and 2 amniotic fluids presenting a trisomy 21 status (DSCR1/CFTR ratio of 1.53 and 1.61, respectively). The results obtained by conventional cytogenetic analysis and our quantitative PCR method were concordant in every case. Our gene-based fluorescent PCR approach represents an alternative molecular method for rapid and reliable detection of trisomy 21, which can be helpful in the prenatal diagnosis of women at high risk of fetal trisomy 21. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Duchenne and Becker muscular dystrophy (D/BMD) are usually problematical when trying to determine the carrier status of at-risk women, which usually has to be based on haplotype or dosage analysis on Southern blots. Using multiplex polymerase chain reaction (PCR) analysis, we have detected deletions in 20 out of 44 D/BMD families with living affected members (45·5 per cent), more often in sporadic cases of DMD (14/22 with detectable deletion) than in familial ones (4/15), the majority (15/20) occurring in the distal region of the D/BMD gene. Four highly informative short tandem repeat polymorphisms (STRPs), which lie within the distal deletion hot spot of the D/BMD gene, can show loss of heterozygosity in carrier females, providing direct evidence of their carrier status. These STRPs greatly improve informativity, with a combined heterozygosity of 100 per cent and with the majority of families informative for three of the four STRPs. In 14/15 (93 per cent) of the families with distal deletions, the STRPs provided direct information on carrier status, and in some cases, they provide valuable information on recombination breakpoints and non-paternity.  相似文献   
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