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871.
A total of 36 ancient human remains from 12 individuals (three tooth/bone samples each) and one sample each of three individuals from the newest time was typed in a blind study using the amelogenin sex test. Prior to this molecular sex determination the sex of the individual was determined morphologically. The success rate of the amelogenin amplifications was >90%. For every individual an unambiguous molecular sex typing result was obtained. Furthermore, the morphological and molecular sex determinations were in accordance with each other, giving evidence for the authenticity and ancient origin of the polymerase chain reaction (PCR) amplifications. 相似文献
872.
A number of DNA polymorphisms have been found to be associated with the pathophysiology of some common disease. If the LDLR polymorphism is directly or indirectly related to some fatal disease, the distribution of the polymorphism may vary with age. We therefore investigated the aging-associated distribution of the LDLR polymorphism. Blood samples were collected from Japanese cadavers (aged 0-91) at autopsy. The LDLR polymorphism was detected using a AmpliType PM PCR Typing kit. When the LDLR genotype was examined in cadavers divided according to age into 0-29 year group, 30-59 year group, and 60-91 year group, there were significant differences in genotype among the three age groups and between the 0-29 year group and 60-91 year group. The LDLR-A genotype tended to be lower in the older cadavers. The present study revealed that there were aging-dependent differences in the distribution of the LDLR polymorphism in autopsy samples, suggesting that a common mutation involved in the occurrence of fatal diseases may be present near the LDLR-A polymorphism locus. 相似文献
873.
Papillary fibroelastoma is a rare benign tumor, occasionally causing angina or sudden death. We report an autopsy case of an aortic valve papillary fibroelastoma with coronary artery embolism. The patient was a 68-year-old Japanese man who had collapsed suddenly in his house. He was a heavy drinker and had a history of liver disease but no notable cardiac event. The autopsy revealed extensive transmural infarction of the inferior wall of the left and right cardiac ventricles. The distal portion of the right coronary artery (segment 4, NYHA) was completely occluded by tumor emboli of the fibroelastoma. At the site of closure of the aortic non-coronary cusp, there was a typical papillary fibroelastoma, which was considered to have originated the coronary embolization. 相似文献
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875.
3,4-methylenedioxyamphetamine (MDA) derivatives are increasingly abused central nervous system stimulants with neurotoxic properties. In recent years a number of controlled substance analogs (designer drugs) with high structural variety reached the illegal market making their identification an arduous task. The underivatized compounds give very similar or even virtually identical electron impact mass spectra containing mainly intense C(n)H(2n+2)N(+) immonium ions. Using tandem mass spectrometry (MS-MS) the additional structural information contained in the collision induced dissoziation (CID) mass spectra of molecular ions using electron impact (EI) and especially chemical ionization (CI) allowed an unequivocal differentiation of 18 studied regioisomeric 1-(methylenedioxyphenyl)-2-propanamines and 1-(methylenedioxyphenyl)-2-butanamines.Further synthetic methods are presented for 1-(3,4-methylenedioxyphenyl)-N-propyl-2-butanamine, N-isopropyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and four 1-(2, 3-methylenedioxyphenyl)-2-butanamines. N-alkylated 1-(3, 4-methylenedioxyphenyl)-2-butanamine compounds (e.g. MBDB) are also known to be abused psychoactive agents (entactogenes) without the sympatomimetic effects of the 3,4-methylenedioxyamphetamines. 相似文献
876.
The binding of charged substances from external aqueous media to hair has been investigated through the use of fluorescence microscopy. Eleven hair samples, reflecting various ethnic groups and cosmetic treatments, were tested. Rhodamine 6G, a cationic dye representative of drugs such as cocaine and opiates, showed incorporation throughout the hair of all samples except one. In contrast, fluorescein, an anionic dye representative of drugs such as THC carboxylic acid, was not readily incorporated. The incorporation of rhodamine 6G was faster for chemically 'straightened' and bleached African-American female hair than for untreated hair. Incorporation of rhodamine 6G followed a pH dependence, but an ionic strength dependence could not be established. These studies support three postulates: (1) electrostatic interactions explain the preferential binding of cationic drugs of abuse to hair; (2) the hair matrix, or the non-helical portion of hair, is accessible to external solutions and thus subject to contamination; and (3) cosmetic treatments may alter the helical portion of hair thereby increasing its accessibility to external contamination. 相似文献
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