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991.
992.
Empirical studies have found that policies aimed at reducing youth access to tobacco have been successful at increasing retail compliance, but their effects on actual tobacco use are mixed. This article presents a model of youth access policies that helps explain the apparently conflicting results in the extant literature, provides a framework for future empirical studies, and suggests implications for public policy. Our model highlights the interaction of components in a well-designed policy, including sufficient compliance checks, penalties, and community involvement. It also illustrates why it will be difficult to eliminate all of youth supply. Nonretail sources, such as borrowing or stealing from parents and siblings and purchasing from older peers through black markets, are an important component of youth supply and become more important as retail access is reduced. The analysis is limited to policies that affect the retail supply of cigarettes but suggests the need for other policies that affect the demand for cigarettes, such as taxes and cessation policies, in order to further reduce youth smoking rates.  相似文献   
993.
Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure.  相似文献   
994.
Several lectins were used to study the localization of glycoconjugates in brain of elderly people and patients with Alzheimer type dementia (ATD) and Down's syndrome (DS). Five kinds of degenerated or deposited materials stained clearly by lectins specific to GalNAC, Gal, Fuc, and/or Man were recognized much in ATD and DS, less in elderly peoples, in addition to the binding of the lectins to neurons. (i) Round shape deposits called corpora amylacea (CA) which consisted of various sizes of round material, existed mainly on the surface of cerebral cortex and some in white matter of the brain. They were colored by Alcian blue (AB), Aldehyde fucsin (AF) and periodic acid shiff (PAS) and weakly by Hematoxylin (H), but not by Eosin (B). They showed clear reactivity with lectins specific to GalNAC, Gal, Fuc and Gal-GalNAC. (ii) Amorphous and variform amyloid deposits existed around blood vessels in the white matter were stained by thioflavin and lectins specific to GalNAC, Gal and Fuc, but not with Man specific lectins and PAS, AB, AF and HE. (iii) Another kind of amyloid deposits which showed a similar characteristic to the previous one and were recognized mainly in white matter and independent blood vessels. These deposits were stained by thioflavin but not by PAS, AB, AF and HE and showed good reactivity with lectins specific to GalNAC, Gal, Fuc, Gal-GalNAC, Gal-GIcNAc and Man. The reactivity with lectins specific to Gal, Fuc, and Man was seen in senile plaques (iv) and neurofibrillary tangles (v). Although at present we are unable to explain the origin of these deposits, it is clear from this study that the glycoconjugates form an integral part of the degeneration in the brain. The lectin staining with GS-I is useful in the forensic pathology to diagnose brain disorders at postmortem examination, since these lectin were able to detect five types of degeneration changes and/or deposits.  相似文献   
995.
The determination of sex from bones or bone fragments considerably contributes to identifying unknown bodies or skeletal remains. Due to temporal change and regional differences anthropometric standards have to be constantly renewed. The present study provides measurements of femoral dimensions in a contemporary German population and analyses sexual dimorphism by discriminant analysis. Maximum length (male: 46.4+/-2.4 cm, female: 43.4+/-2.4 cm), maximum midshaft diameter (male: 3.1+/-0.2 cm, female: 2.8+/-0.2 cm), condylar width (male: 8.4+/-1.0 cm, female: 7.7+/-0.5 cm), vertical head diameter (male: 4.9+/-0.3 cm, female: 4.4+/-0.3 cm), head circumference (male: 15.7+/-0.8 cm, female: 13.8+/-1.0 cm) and transverse head diameter (male: 4.9+/-0.3 cm, female: 4.3+/-0.3 cm) were measured in 170 femora, 100 from male (age: 16-92 years, mean: 60.8 years; body height: 153-190 cm, mean: 171 cm) and 70 from female (age: 20-96 years, mean: 72 years; body height: 146-175 cm, mean: 161 cm) individuals. In the discriminant analysis (leave-one-out-method) 67.7% of cases could be grouped correctly with the maximum length alone, 72.4% with the maximum midshaft diameter, 81.4% with the condylar width, 86.8% with the vertical head diameter, 87.7% with the head circumference and 89.6% with the transverse head diameter. The stepwise procedure with all head measurements showed that the results for the transverse head diameter could not be improved. With all measurements subjected to stepwise procedure 91.7% of cases could be classified correctly combining midshaft diameter and head circumference (D=3.012xmidshaft diameter in cm+0.780xhead circumference in cm 20.569).  相似文献   
996.
Fentanyl is a very strong opioid with analgesic properties that are approximately 80 times stronger than those of morphine and therefore is used in major surgery and treatment of pain in tumor patients. Cases of fentanyl abuse by intravenous injection, inhalation, oral or nasal application have been reported especially in the USA. Therapeutic levels of fentanyl are as low as 1 ng/ml of serum and therefore a screening test must have a detection limit below that concentration. Recently three non-radioactive enzyme immunoassays (EIAs) have become commercially available from COZART, STC and DIAGNOSTIX, all of them supplied by MAHSAN Diagnostika for evaluation with serum samples from forensic and clinical cases. A calibration curve is obtained with samples that contain 0, 0.1, 0.5, 1 and 5 ng fentanyl per ml of negative serum. The calibration curve of COZART is especially in the low range, steeper than those of STC and DIAGNOSTIX. The cut-off for all these EIAs, however, can be set at 0.5 ng/ml. After the administration of therapeutic doses, fentanyl concentrations were between 3 and more than 5 ng/ml as determined with the EIAs. The presence of the typical drugs of abuse, e.g. heroin, methadone, cocaine, cannabinoids and amphetamines including the derivatives of methylenedioxyamphetamine, don't generate false-positive results. No cross-reactivity was also observed at toxic levels of benzodiazepines and paracetamol and therapeutic levels of barbiturates, phenothiazines, antidepressants and analgesics. The EIAs tested so far appear to be suitable for the detection of fentanyl at therapeutic levels. False-positive results or cross-reactivity towards other compounds have not been observed.  相似文献   
997.
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   
998.
To outline the recent features of methamphetamine-related fatalities from the medico-legal point of view, a retrospective investigation of forensic autopsy cases involving methamphetamine during a 5-year period (1994-1998) in the southern half of Osaka city and surrounding areas (about 1.57 million population) was undertaken. Among 646 autopsy cases, methamphetamine was detected in 15 victims (nine males, six females; 16-71 years of age; most frequently in males in their thirties). Primary scenes of fatal events were concentrated in the middle of the city. About half of them were transferred from emergency medical centers (survival time, up to 30 h). The cause and manner of death were: methamphetamine poisoning (n=4), homicide (n=4), accidental falls and aspiration from drug abuse (n=4), fire death (n=1), myocardial infarction (n=1), and cerebral hemorrhage (n=1) under drug influence. Usually injection scars and fresh puncture sites were found. Blood methamphetamine concentrations were 2.29-17.05 micromol/dl in the fatal poisoning, 0. 44-3.80 micromol/dl in deaths from other extrinsic causes (trauma), and 1.35-2.17 micromol/dl in cardio- and cerebrovascular strokes. Common complications were cardiomyopathy, cerebral perivasculitis and liver cirrhosis/interstitial hepatitis. Fatal and nonfatal methamphetamine poisonings are separately dealt with by the administrative medical examiner's office and in emergency medical centers. Tightly cooperative approaches of clinical and medico-legal experts are required for the effective social and medical management of drug abuse.  相似文献   
999.
In four forensic cases of unidentified skeletal remains investigated in the last year, we were able to attach three to missing persons. In one case we could show that the discovered bone sample did not fit to a missing child. The method for mitochondrial DNA analysis for the routine identification of skeletal remains was established in our institute by typing bone samples of defined age obtained from Frankfurt's cemetery. Reproducible results were obtained for bones up to 75 years old. For analysis the bone samples were pulverised to fine powder, decalcified and DNA was extracted. From the DNA we amplified a 404-bp fragment from HV-1 and a 379-bp fragment from HV-2 of the mtDNA control region. After sequencing of the PCR products, the results were compared to the Anderson reference sequence and to putative maternal relatives.  相似文献   
1000.
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   
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