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141.
An accurate and simple method was developed to determine the level of toluene in urine and blood quantitatively by using the gas chromatography/mass spectrometry (GC/MS) with headspace--solid phase microextraction (HS-SPME) technique. An assembly of SPME with a replaceable extraction fiber, coated with 100 microm polydimethylsiloxane, was used. The detection limit of toluene in blood and urine with HS-SPME technique was 10 times higher than that with headspace (HS) technique. To compare the HS-SPME with HS technique for the determination of toluene in biological fluids, blood and urine samples from glue sniffers were analyzed by both methods. The level of toluene by the two techniques was highly correlated: the correlation coefficient (r2) between the two sets of values were 0.98 and 0.96 in urine and blood, respectively.  相似文献   
142.
布卢姆认知领域教育目标分类理论评析   总被引:4,自引:0,他引:4  
生物学上动植物分类学的理论为布卢姆构造其认知领域教育目标分类理论提供了借鉴。根据人的认知目标是从识记相对简单的知识到非常抽象的思维这样一个渐进过程,布卢姆把教育的认知目标分为六大主类(识记、领会、应用、分析、综合及评价)以及其它亚类。这种理论被证明“对研究和教学两方面都是相当有用的”。但由于布卢姆认知目标分类理论不是认识过程的先后层次,不是行为发展的过程,没有揭示出能力形成的内在机制,也缺乏学习理论的指导,导致了教育实践中的诸多困惑。我们应对布卢姆理论进行深刻的反思,立足本国实际,构建本土的教育目标分类理论。  相似文献   
143.
传统的发展观把经济发展作为发展的全部,从而导致对GDP的崇拜和迷信。但经济繁荣并不必然导致社会稳定。如果没有政府宏观调控和积极的社会政策干预,就会出现两极分化和其他社会问题。所以,马克思主义要求建立以人为本,促进经济社会和人的共同发展的科学发展观。  相似文献   
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Asphyxia, not an uncommon cause of sudden death, may result from numerous etiologies. Foreign-body aspiration and strangulation are 2 extrinsic causes. Airway obstruction may also be caused by laryngeal edema, asthma, infection, or anaphylaxis. Chronic causes of asphyxia include musculoskeletal diseases (eg, muscular dystrophy, amyotrophic lateral sclerosis), neurologic disorders (eg, myasthenia gravis, multiple sclerosis), respiratory disease (eg, emphysema, chronic bronchitis), or tumors. The manner of death in cases of asphyxiation may be natural, accidental, homicide, or suicide. For the death investigator, determining the cause and manner of death can often be quite challenging.We report here 2 cases of an esophageal fibrovascular polyp causing sudden asphyxial death, review of the literature, and discussion of other differential diagnoses in the case of asphyxial death.  相似文献   
147.
Hypertrophic cardiomyopathy (HCM) is a disease process which results in a large, heavy heart, with hypertrophy of the interventricular septum (IVS) and left ventricle. HCM accounts for a significant number of cases of sudden cardiac death each year, most infamously in young athletes. The prevalence of the disease has increased over the past several years due to advances in clinical diagnosis and molecular genetic studies. Over this same period, new forms of treatment also have emerged. One such treatment is alcohol septal ablation (ASA). ASA is a procedure performed by a cardiologist, via cardiac catheterization, by injecting pure ethanol into selected arteries which supply the IVS, resulting in a targeted myocardial infarction. This infarct then retracts and forms a scar, decreasing the outflow obstruction and improving the patient's clinical symptoms.The authors report 2 cases of death following ASA treatment of HCM. The first, a 56-year-old male, had his ASA procedure 10 days prior to death. The second decedent, a 76-year-old female, had her procedure only 30 hours before death. These case reports are followed by a discussion about HCM, including pathology, treatments, and treatment-related pathology, before closing with a discussion about death certification in the cases presented and therapy-related deaths in general.  相似文献   
148.
This study was designed to compare the qualitative results and concentrations of methamphetamine (MA) and its metabolite amphetamine (AP) in head hair and hair collected from different parts of the body (axillae and pubis). Hair from subjects (N = 14) suspected MA users was simultaneously collected. Hair preparation involved washing step, fine cutting, overnight extraction, derivatization by the trifluoroacetic anhydride, and gas chromatography/mass spectrometry (GC/MS) using selective ion monitoring. In this study, we found a good correlation of the qualitative results for MA between head hair and hair on other parts of the body, but there were some differences in concentrations of MA and AP. Namely, the concentrations of MA and AP were higher in axillary and pubic hair than in head hair.  相似文献   
149.
In this study, 12 Y-specific STR loci--DYS391, DYS389 I, DYS439, DYS389 II, DYS438, DYS437, DYS19, DYS392, DYS393, DYS390, DYS385a/b--were analyzed in 259 unrelated males from the southern populations in Korea using the PowerPlex Y PCR system.  相似文献   
150.
The prevalence and age distribution of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in hair samples by gas chromatography/mass spectrometry (GC/MS) were studied. The recoveries obtained from hair were 97% and 99% for MDMA and MDA, respectively. The inter- and intra-assay precision and accuracy were determined. Out of 791 hair samples, 44 (5.6 %) contained MDMA and/or MDA. Out of these 44 subjects, urinalyses from 35 were negative for both MDMA and MDA, while only 9 were positive. We also evaluated concentrations of MDMA and MDA, and the metabolite-to-parent drug ratios. This study showed that the abuse of MDMA or MDA was found principally among young adults and male abusers. We found the epidemiology of ecstasy users in Korea between March 2002 and April 2003.  相似文献   
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