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A new method for diatom detection is described. It includes an ultrasonic irradiation procedure with the use of a tissue solubilizer. The method is easy to carry out and is less time-consuming than previous techniques. 相似文献
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Methamphetamine in urine samples from abusers was detected by the latex agglutination inhibition reaction test with latex-antibody (Latex-Ab) and latex-methamphetamine (Latex-MA) reagents. Anti-methamphetamine antibody was produced in rabbits by immunization with bovine serum albumin (BSA)-methamphetamine conjugate. Latex particles were coated with antibodies or with rabbit serum albumin (RSA)-methamphetamine conjugate to obtain Latex-Ab and Latex-MA reagents, respectively. The results are read at 4-5 min after mixing the latex reagents. The sensitivity of this method for methamphetamine was 0.4 micrograms/ml urine. Methamphetamine analogs (methylephedrine, amphetamine, phentermine, methoxyphenamine, ephedrine, beta-phenylethylamine, OH-methamphetamine, OH-amphetamine, and OH-ephedrine) all cross-react in varying degrees, while glucosiurea and albuminurea give false positive results in the tests. Though attention must be paid to these effects this simple and rapid test is suitable for the mass screening of urine samples. 相似文献
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Ohtani S Yamada Y Yamamoto T Arany S Gonmori K Yoshioka N 《Journal of forensic sciences》2004,49(3):441-445
Aspartic acid (Asp) is generally used for estimation of age by measuring the degree of racemization. For other amino acids, however, there are few reports regarding the usefulness of the degree of racemization for the estimation of age. Accordingly, in this study using the femur (obtained from 21 cadavers) as the specimen, we measured the degree of racemization of glutamic acid (Glu) and alanine (Ala) along with Asp in the total amino acid (TAA) fraction as well as in acid-insoluble collagen-rich (IC) and acid-soluble peptide (SP) sub-fractions. We compared the degrees of racemization of each amino acid and the accuracy of the ages estimated from them. The degree of racemization and the reaction rate of racemization were ranked in the order of Asp > Glu > Ala in the TAA and IC fractions, but Asp > Ala > Glu in the SP fraction. It is noteworthy that the degrees of racemization differed between the three amino acids depending on the fraction tested. The correlation coefficient (r) between the degree of racemization and the chronological age was higher in the SP than in the TAA or IC fraction. Among three amino acids, Asp showed the highest correlation coefficient as predicted. The present study confirmed that Asp from the SP fraction is the best indicator for age estimation using racemization rates. 相似文献
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Characterization and haplotype analysis of 10 novel Y-STR loci in Chinese Han population 总被引:3,自引:0,他引:3
Dai HL Wang XD Li YB Wu J Zhang J Zhang HJ Dong JG Hou YP 《Forensic science international》2004,145(1):47-55
In this study, we analyzed allelic sequences of 10 novel Y-specific STR loci, DYS454, DYS510, DYS513, DYS520, DYS542, DYS544, DYS552, DYS561, DYS587 and DYS593, surveyed the distribution of haplotypes in a Chinese Han population. Extracted DNA was amplified with PCR, followed by a horizontal non-denaturing polyacrylamide gel electrophoresis with discontinuous buffer system. Purified alleles were sequenced on DNA sequencer (ABI Model 377) to verify the number of motif repeats. The number of alleles observed at each locus ranged from 3 to 8, yielding 102 haplotypes in 103 unrelated males samples. The allele diversity values for each locus ranged from 0.2099 (DYS544) to 0.7523 (DYS552). The haplotype diversity using all these loci was 0.9998. Our study revealed that they were valuable Y-specific markers for forensic applications. 相似文献