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DNA size polymorphisms were utilized in a study of 24 natural populations of Ceratitis capitata Wiedemann (Diptera: Tephritidae) from Argentina. The first intron of alcohol dehydrogenase 1 gene (Adh1) was amplified using exon priming intron crossing‐polymerase chain reaction. Three size variants were detected among the 307 samples analyzed. To better differentiate the size variants, further digestion of PCR products with the EcoRI restriction enzyme was carried out. Complete nucleotide sequences of the three‐allele variants were obtained and single changes, insertions, deletions, and EcoRI recognition sites were located. Population allele frequencies were analyzed and a global mean heterozygosity (He) of 0.33 was obtained. In most populations, observed allelic frequencies conformed to Hardy–Weinberg expectations. Significant differences between provinces and sampling sites within these provinces, and among some populations were found. The average number of insects exchanged among populations (Nm) was estimated and high values were observed between Argentina and populations from two African countries (Morocco and Kenya), Australia, and Hawaii (Kauai). Pest introduction sources and dispersion patterns in Argentina are discussed based on these results as well as on available bibliographical data.  相似文献   
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Background  

Determination of clot lysis times on whole blood, diluted whole blood, plasma or plasma fraction has been used for many years to assess the overall activity of the fibrinolytic system. We designed a completely computerised semi-automatic 8-channel device for measurement and determination of fibrin clot lysis. The lysis time is evaluated by a mathematical analysis of the lysis curve and the results are expressed in minute (range: 5 to 9999). We have used this new device for Euglobulin Clot Lysis Time (ECLT) determination, which is the most common test used in laboratories to estimate plasma fibrinolytic capacity.  相似文献   
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Huret  J. L.  Benz  Elisabeth  Guilhot  F.  Brizard  A.  Tanzer  J. 《Human genetics》1986,72(1):98-100
Summary Fixed metaphase chromosomes of different species and genera of Primates (five species of Macaca genus and Callithrix acchus) have been studied after Alu I restriction enzyme digestion and DA-DAPI counterstaining, in the attempt to determine some qualitative characteristics of their DNAs and specifically of the DNA localized in the heterochromatic components of the karyotypes. The results have been discussed in the light of those already published on humans, confirming the potentiality of this approach in the study of the phyloevolutive relationships in Primates.  相似文献   
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