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991.
The present paper describes an integrated diagnostic strategy to check the physical fitness of subjects, formerly users of illicit drugs, to obtain a driving license, after having quit their addiction. According to the Italian law, applicants for a driving license with a history of drug abuse must give evidence to have quit this behaviour and to show no risk of relapse in the future. To prove this, at our institute, they undergo medical examination, hair analysis and a urinalysis program on eight seriate samples, collected over about 40 days. About 700 subjects per year are investigated with this strategy. The hair samples are screened for opiates (morphine), cocaine and ecstasy, the most abused illicit substances in our region, by using commercial radioimmunoassays adopting cut-off levels of 0.1 ng/mg. All positive samples and about 10% of negatives are confirmed by high-performance liquid chromatography. Further confirmation of results can be carried out by capillary electrophoresis (and/or GC/MS or MS/MS). In 1998, the prevalence of positives for morphine, cocaine and ecstasy was 4.8, 11.3 and 2.6%, respectively. In this year, for the first time, the percentage of hair samples positive for cocaine was greater than that for opiates. The results of this integrated diagnostic strategy are presented and discussed, with particular emphasis on the comparison between hair analysis on a single sample and seriate urinalyses (on eight samples).  相似文献   
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994.
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   
995.
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   
996.
Cases of misconduct in scientific research have enforced a lively public and scientific discussion. The international scientific community has been engaged during the last years in the search for adequate responses to fraud and misconduct. Most of the new guidelines emphasize the responsibility of researchers and scientific institutions for preventive measures; the teaching of research ethics should be included in undergraduate and postgraduate academic education. At the Universities of Ulm and Marburg members of the 'Study group Ethics in Medicine' are developing a teaching program in Research Ethics. They now offer courses: teaching in small groups (7-15 participants) with structured case discussions. These courses are not mandatory. The first steps in the development of the teaching program for young scientists in medicine, biology, chemistry, and physics have been taken. The fields of conflicts in these different fields of science are very similar. We offered five case discussion sessions with mixed groups (postgraduate students, postdocs, head of departments) and the first results are very positive: high acceptance, high motivation, high demand for next courses.  相似文献   
997.
998.
999.
So long as procreation continues to remain a central driving force in a marital relationship, and the family the very core of progressive society, efforts will be undertaken to expand the period of fecundity and combat infertility. Genetic planning and eugenic programming are more rational and humane alternatives to population regulation than death by famine and war. Genetic enhancement technologies and the scientific research undertaken to advance them should be viewed as not only aiding (or, sometimes resolving) the tragedy of infertility in family planning, but as a tool for enhancing the health of a Nation's citizens by engineering man's genetic weaknesses out of the line of inheritance. Put simply, healthier and genetically sound individuals have a much better opportunity for pursuing and achieving the "good life" and making a significant contribution to society's greater well being.  相似文献   
1000.
应用40Hz听觉相关电位与听性脑干反应评估听阈   总被引:5,自引:2,他引:3  
Fan L  SUN H  ZHU G  SHEN Y 《法医学杂志》2000,16(4):193-195
对 42例 74耳(正常听力组 32耳,检案中主诉听力下降 42耳)分别进行纯音测定,声导抗测定,听性脑干反应 (Auditory Brainstem Response,ABR)及 0.5~ 2kHz范围的 40Hz听觉相关电位 (40Hertz Auditory Event- related Potential,40Hz AERP)测定,对其中 20耳进行睡眠及清醒两种状态的 40Hz AERP测定。将纯音听阈、 40Hz AERP反应阈、 ABR反应阈三者之间进行比较分析。结果表明,正常听力耳 40Hz AERP反应阈值较纯音测听阈值高,在不同频率的校正值 (差值 )不同, 0.5 kHz为 12.7± 6.4(dBnHL); 1kHz为 14.7± 6.3(dBnHL); 2 kHz为 15± 5.6(dBnHL)。 ABR阈值比行为听阈高,校正值为 8.9± 5.3(dBnHL)。睡眠状态时 40Hz AERP阈值较清醒状态阈值高,校正值为 9.7± 2.45(dBnHL)。检案中主诉听力下降者主、客观语音频率均值之间明显不相符 ,误差率为 61%。本研究表明单纯使用 ABR、纯音测听中任何一种方法估计语音频率听阈均有一定的误差。  相似文献   
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