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961.
Mitchell E Krous HF Donald T Byard RW 《The American journal of forensic medicine and pathology》2000,21(4):395-400
Retrospective analysis of autopsy findings in 60 infants who had been found unexpectedly dead in their cribs or beds in South Australia from 1994 to 1998 was undertaken to determine the diagnostic usefulness of individual stages in the postmortem investigation. Positive findings occurred in 2 of 43 scene examinations (3%), 2 of 60 external examinations (3%), 2 of 11 radiologic examinations (18%), 8 of 60 internal examinations (13%), 7 of 60 histologic examinations (12%), and 3 of 58 microbiologic examinations (5%). No positive findings were detected on toxicologic screening. Not every case underwent each diagnostic step. This gave alternative diagnoses to sudden infant death syndrome (SIDS) in 15 cases (25%). This study demonstrates an increase in the percentage of cases of unexpected infant death due to causes other than SIDS; it also shows the diagnostic yield of individual stages in the postmortem evaluation of such cases. Negative findings were important in giving validity to the diagnosis in the 45 cases that were ultimately designated as SIDS. 相似文献
962.
963.
This study was aimed at measuring the approximate amount of petrol transferred on to the clothing and shoes of a person during the action of pouring petrol around a room. Two different heights of pouring and two different types of floor surface (carpet and concrete) were investigated. Results show that for all the combinations examined petrol was always transferred to the shoes and often transferred to the upper and lower clothing. This information illustrates the necessity of analysing the clothing and particularly the shoes of any suspected arsonists for the presence of hydrocarbon fuels. 相似文献
964.
A Portuguese Caucasian population of 146 unrelated individuals was studied. DNA samples were amplified by multiplex PCR for D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820 using the AmpFlSTR Profiler Plus PCR Amplification Kit (Perkin-Elmer). All loci met Hardy-Weinberg expectations. Forensic statistical parameters were according to those obtained by other authors. Statistical differences were observed concerning three loci when comparing the Portuguese Caucasian population and an Italian Caucasian population, although these differences mainly concern the less frequent alleles. Eighty-three paternity investigation cases were analysed. Exclusions in between three and nine loci were observed in all the 23 exclusion cases obtained. Most of the non-exclusion cases had probability of paternity > 99.9%. Two cases with an isolated genetic incompatibility between the alleged father and the child were detected, which may indicate probable mutation cases. These results demonstrate that the AmpFlSTR Profiler Plus is a suitable multiplex for paternity investigation in the Portuguese population. 相似文献
965.
Lantz PM Richardson LC Sever LE Macklem DJ Hare ML Orians CE Henson R 《Journal of health politics, policy and law》2000,25(3):451-471
Funding for many mass screening programs for low-income and uninsured populations provides resources for screening tests, yet only rarely does it provide coverage for necessary follow-up diagnostic and treatment services. The National Breast and Cervical Cancer Early Detection Program (NBCCEDP), a federally funded initiative that provides cancer screening to low-income uninsured and underinsured women, covers some diagnostic follow-up tests and no treatment services. We conducted in-depth case studies of seven state programs participating in the NBCCEDP to investigate the strategies and approaches being used to secure diagnostic and treatment services. The results suggest that the program relies on a patchwork of resources--at state and local levels--to provide diagnostic and treatment services. This includes a number of components of local safety nets, all of which are unstable and have uncertain futures. Public health disease-screening initiatives need to reconsider the feasibility of continued reliance on case-by-case appeals to the local safety net for diagnostic follow-up and treatment services. 相似文献
966.
967.
Screening and determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry 总被引:4,自引:0,他引:4
Benzodiazepines are one of the most widely prescribed drugs for the treatment of a wide spectrum of clinical disorders. They are used as anticonvulsants, anxiolytics, hypnotics or muscle relaxants with different duration of action. In this paper, a simple and sensitive method for the determination of benzodiazepines in whole blood using solid-phase extraction and gas chromatography/mass spectrometry (GC/MS) is described. The drugs spiked in whole blood were extracted with an Oasis HLB solid-phase extraction cartridge (Waters), which contains a copolymer designed to have a hydrophilic-lipophilic balance. GC/MS analysis was performed using a Shimadzu QP-5000 equipped with a BPX5 capillary column (15 mx0.32 mm I.D., film thickness 0.25 microm, SGE). Nineteen benzodiazepines and two thienodiazepines were well separated from each other on their SIM chromatograms and also on the TIC with the exception of oxazolam to cloxazolam separation. The blank extract from whole blood gave no peaks that interfered with all benzodiazepines and thienodiazepines on the chromatogram. The calibration curves for selected benzodiazepines with fludiazepam as an internal standard showed excellent linearity over the concentration range 5-500 ng/ml blood with a correlation coefficients of >0.995. The detection limits ranged from 0.2 to 20 ng/ml blood. The method is simple and sensitive for the determination of benzodiazepines in whole blood and seems to be useful in the practice of forensic science. 相似文献
968.
Weinmann W Vogt S Goerke R Müller C Bromberger A 《Forensic science international》2000,113(1-3):381-387
A fast method using liquid-liquid extraction and HPLC/tandem-mass spectrometry (LC/MS/MS) was developed for the simultaneous detection of 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid beta-glucuronide (THC-COOH-glucuronide) and 11-Nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. This highly specific method, which combines chromatographic separation and MS/MS analysis, can be used for the confirmation of positive immunoassay results even without hydrolysis of the sample or derivatisation of extracts. Liquid-liquid extraction was optimised: with ethylacetate/diethylether (1:1, v/v) THC-COOH-glucuronide and THC-COOH could be extracted in one step. Molecular ions of the glucuronide (MH(+), m/z 521) and THC-COOH (MH(+), m/z 345) were generated using a PE/SCIEX turboionspray source in positive ionisation mode; specific fragmentation was performed in the collision cell of an API 365 triple-quadrupole mass spectrometer and yielded major fragments at m/z 345 (for THC-COOH-glucuronide) and m/z 327 as well as m/z 299 for both cannabinoids. Chromatographic separation was performed using a reversed-phase C8 column and gradient elution with 0.1% formic acid/1 mM ammonium formate and acetonitrile/0.1% formic acid. Retention times were 22.2 min for the glucuronide and 26.8 min for THC-COOH. After enzymatic hydrolysis of urine samples with beta-glucuronidase/arylsulfatase (37 degrees C, 5 h), THC-COOH-glucuronide was no longer detectable by LC/MS/MS in urine samples. However, the THC-COOH concentration was increased. For quantitation of THC-COOH, THC-COOH-D(3) was added to the urine samples as internal standard prior to analysis. From the difference of THC-COOH in the native urine and urine after enzymatic hydrolysis, molar concentration ratios of THC-COOH-glucuronide/THC-COOH in urine samples of cannabis users were determined and found to be between 1.3 and 4.5. 相似文献
969.
Pontocerebellar hypoplasia (PCH) is a very rare congenital (autosomal recessive) condition with fetal onset. Only a few cases have been published on the basis of both clinical data (symptoms/neuroradiological imaging) and autopsy results. This paper reports on such a case involving a 1.5-year-old male infant. The child suffered from severe psychomotor delay, extrapyramidal dyskinesia and epileptic seizures, but did not exhibit signs of spinal muscular atrophy as related to PCH type 1. Magnetic resonance imaging (MRI) at the age of 6 months demonstrated olivo-pontine and bilateral cerebellar hypoplasia. The boy was unexpectedly found dead. Autopsy disclosed a severe aspiration of gastric contents as the final cause of death. The neuropathological examination confirmed PCH type 2 (according to Barth [Brain Dev., 15 (1993) 411-422]) with marked microcephaly and olivopontocerebellar hypoplasia. Histologically, decreased density of olivo-pontine neurons, reduction of granular and Purkinje's cell layers of the cerebellum, slight astroglial proliferation and fragmented appearance of the dentate nuclei were observed. The immunohistochemical expression pattern was determined using antibodies against glial fibrillary acidic protein, synaptophysin and neurofilament protein. Summarizing, typical features of PCH type 2 were present and proved by clinical course, MRI and autopsy. Despite severe symptoms due to a natural disease this rare neurogenetic entity can become of forensic interest, when sudden unexpected death occurs. 相似文献
970.
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