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961.
Short tandem repeat (STR) markers are commonly used in basic genetic research and in human identification testing. Clinically, STRs can be used to study genetic alterations in tumors. A genetic deletion common to many types of cancer is referred to as the loss of heterozygosity (LOH). Numerous examples of LOH in cancer have been described and some have been mapped to areas located in close proximity to markers employed in human identity testing. Despite this fact, LOH has rarely been observed for STR loci commonly employed in forensic testing. Recently, for medico-legal purposes, we were asked to determine whether a tissue biopsy originated from a particular individual. For a reference source we assessed two specimens, one from normal tissue and one from cancerous tissue. When both reference specimens were used to generate DNA profiles, we observed LOH at one STR locus, D13S317. As demonstrated in other cancers only the cancerous biopsy demonstrated LOH. The forensic community should be cognizant of these unusual circumstances because, as identification of human DNA continues to be used more extensively, certain instances will arise in which reference material will not be readily available. In these situations, archived specimens may be employed as a reference source. Clinical specimens such as tissue biopsies should be used with caution if they have not been confirmed to contain normal tissue.  相似文献   
962.
Allele frequencies for six DNA polymorphisms have been studied in a population sample from Cantabria (middle north Spain) using the polymerase chain reaction. The HLA-DQA1 locus was analyzed by the reverse dot-blot technique and the other five by polyacrylamide gel electrophoresis followed by silver staining. Six alleles were found for HLA-DQA1. 15 alleles for D1S80, 6 alleles for HUMTHO1 and HUMCSF1PO, 7 for HUMTPOX and 8 alleles for HUMVWA. The 21 repeat allele in HUMVWA had not previously been reported in a Spanish population. The genotype distributions met Hardy-Weinberg expectations for all the systems and some statistical parameters of forensic interest were calculated. Comparisons with other populations revealed significant differences for HLA-DQA1, HUMVWA and HUMTHO1, with interracial differences being more pronounced than between Spanish populations. The HUMVWA system showed the highest forensic efficiency of the six polymorphisms studied.  相似文献   
963.
This report contains the results of two population studies on the X chromosome STR HumHPRTB carried out in a Northern and a Southern region of Germany. The numbers of unrelated individuals were 443 and 335, respectively. Eight alleles (alleles 9 to 16) were found. In female individuals 29 different genotypes were encountered. In German populations the HumHPRTB STR was characterized by the following data: PIC = 0.750; HET = 0.769: MEC = 0.556. Allele distribution met the Hardy-Weinberg expectations. The Northern and Southern populations did not show any significant differences.  相似文献   
964.
We report a fatal case of death due to unusual aspiration of sardine fry in an elderly Japanese man with lung cancer. The cause of death was sudden respiratory arrest while eating. Autopsy revealed peculiar materials with cell nests and pigmented particles, together with striated muscle and skin, in the ectatic bronchioles of the left lower lobe. Serial histologic sections suggested that the structures observed were the eyeballs of small animals that appeared to have been inhaled. The patient had habitually eaten sardine fry and rice gruel, which were also detected in the gastric contents. Therefore, the eyes were considered to be those of the fry, which is a popular food item in Japan. This was confirmed by histologic examination of fry that were obtained commercially.  相似文献   
965.
Drug abuse and its consequences are everyday problems encountered globally, and Scotland is no exception. During a study of drug-related deaths in the Strathclyde region of Scotland it was noted that known drug users who had recently been released from prison were at high risk of dying from a drug overdose. The majority of deaths occurred within one week of the release date and polydrug use was prevalent. Morphine was the most frequently encountered drug and this was found in combination with benzodiazepines in a significant number of cases. This paper highlights the dangers of resuming drug consumption following a period of abstinence.  相似文献   
966.
The analysis of 35,312 cannabis preparations confiscated in the USA over a period of 18 years for delta-9-tetrahydrocannabinol (delta9-THC) and other major cannabinoids is reported. Samples were identified as cannabis, hashish, or hash oil. Cannabis samples were further subdivided into marijuana (loose material, kilobricks and buds), sinsemilla, Thai sticks and ditchweed. The data showed that more than 82% of all confiscated samples were in the marijuana category for every year except 1980 (61%) and 1981 (75%). The potency (concentration of delta9-THC) of marijuana samples rose from less than 1.5% in 1980 to approximately 3.3% in 1983 and 1984, then fluctuated around 3% till 1992. Since 1992, the potency of confiscated marijuana samples has continuously risen, going from 3.1% in 1992 to 4.2% in 1997. The average concentration of delta9-THC in all cannabis samples showed a gradual rise from 3% in 1991 to 4.47% in 1997. Hashish and hash oil, on the other hand, showed no specific potency trends. Other major cannabinoids [cannabidiol (CBD), cannabinol (CBN), and cannabichromene (CBC)] showed no significant change in their concentration over the years.  相似文献   
967.
968.
969.
Anti-P1 immunoreagents with incomplete antibodies are intended for detection of antigen of different degree of manifestation in blood traces during expert evaluation of material evidences by the adsorption-elution test. These reagents can be used for detecting weakly manifest P1 antigen in liquid blood in forensic medical studies.  相似文献   
970.
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