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991.
Summary The results of HLA-DQ typing from 42 routine forensic cases using the polymerase chain reaction (PCR) were analyzed regarding the reliability, discrimination efficiency and informative value of this system in a given case. The cases included stain typing from a variety of different substrates, i.e. blood and semen stains, mixed body fluids, single hairs, cigarette butts, material from fingernail scratches, as well as identification and paternity cases on postmortem and fixed tissue. A total of 125 individual stain and tissue samples were included. PCR amplification was achieved in 70% of these samples. In cases with mixed body fluids, e.g. sperm and vaginal cells from rape cases, DQ typing was always carried out successfully. However, only approx. 42% of all samples that could be typed were relevant regarding the inclusion or exclusion of a suspect. This was mostly due to the limited number of alleles that can be typed at the HLA-DQ locus or to the fact that the stain or hair samples did not originate from the perpetrator, but from the victim or from other persons not related to the crime.  相似文献   
992.
The abdominal left ventricular assist device (ALVAD) is an order of magnitude more effective than conventional intra-aortic balloon pumping (IABP) in unloading and providing circulatory support to the failing left ventricle. This is a report of a unique case which demonstrates that in the absence of pulmonary vascular obstruction or constriction, the ALVAD can substitute for both left and right heart function. A 21-year-old patient with a congenital bicuspid aortic valve developed acute valvular endocarditis which rapidly progressed to congestive heart failure. An operation was undertaken, the mitral and aortic valves were excised and replaced by porcine heterografts, and a fistula from the right sinus of Valsalva to the right ventricle was closed. When coronary circulation was restored, irreversible ischemic contracture of the left ventricle, or "stone heart" syndrome, developed and emergency ALVAD or partial artificial heart implantation was effected. This device functioned as a total artificial heart for nearly six days, while a donor heart was sought. The patient then underwent removal of the ALVAD and cardiac and renal allografting. The transplanted heart functioned well, but the patient expired fifteen days later from gram-negative sepsis.  相似文献   
993.
A genetic analysis of amphetamine-induced hyperthermia was conducted in inbred mice of the strains Balb/c and C3H and in their F1F2 and backcross generations. The results of biometric analysis indicate that the effect of amphetamine on body temperature is genetically determined. The mode of inheritance characterized by a partial dominance (Balb/C over C3H strain). However, a possible matermal effect of C3H can overcome the dominant effect in male progenies and inhibit amphetamine hyperthermic effect.  相似文献   
994.
This article replicates for Kinsey's male sample the decade-of-birth analyses provided in the Kinsey female volume. Five generations of male respondents are compared in terms of total frequency of sexual activity, and frequency and incidence of nine specific categories of sexual behavior. In general, unmarried males born after 1900 experienced more frequent sexual outlet than did nineteenth-century males. Additionally, the proportion of total outlet devoted to various specific activities varied by birth decade. Solitary masturbation rose somewhat spectacularly in significance with the passing decades, while nocturnal emissions and animal contacts declined. Orgasms provided by heterosexual activities increased slightly for the early twentieth-century generations, but then declined to a point below their nineteenth-century levels. Although homosexual contacts accounted for a constant percentage of total outlet for unmarried males over the five generations, more males in each succeeding generation were actively engaging in homosexual activity, at least on a casual basis. Similarly, although heterosexual contacts accounted for a smaller percentage of all activity among the unmarried in later generations, more of the later-born males had engaged in such activity at least once. For married males, on the other hand, frequency of total outlet was unaffected by generation. A large and stable proportion of this outlet was provided by marital coitus. Although more males in later generations had experienced extramarital contacts, such activities accounted for a small and reasonably stable proportion of total outlet, when frequency of occurrence was considered. Masturbation gained in significance, while nocturnal emissions and homosexual contacts declined, and animal contacts among the married were almost nonexistent in all generations.  相似文献   
995.
Three hallucinogens (d-lysergicacid diethylamide (LSD), mescaline, psilocybin) and two cannabinoid derivatives (tetrahydrocannabinol (THC), synhexyl) were tested for their long-term effects on the EEG of the cat. The drug-induced alterations in the EEG frequency spectrum were "drug-specific" in the sense that they would be statistically unlikely to occur during sleep-waking behavior. The two classes of compounds produced distinctly different EEG effects which were remarkably similar within each class. The duration of activity and relative potencies were consistent with those obtained by other measures, both in cats and in other species including man.  相似文献   
996.
Summary A gas chromatographic method for analyzing the urinary metabolites of n-hexane (2-hexanol, 2,5-hexanedione, 2,5-dimethylfuran and -valerolactone), of 2-methylpentane (2-methyl-2-pentanol), of 3-methylpentane (3-methyl-2-pentanol), and of cyclohexane (cyclohexanol) was developed. Processing of urine and the gas chromatographic conditions are described. The recovery rate of all hexane metabolites, except 2,5-dimethylfuran, ranged between 92 and 100%. The variation coefficient of metabolites determination was between 1.5 and 5%, apart from 2,5-dimethylfuran determination for which the variation coefficient was 15%. The detection limits ranged between 0.2 and 0.7 mg/1 and between 0.05 and 0.1 mg/1 when a packed or capillary column was used. Results obtained from a packed and capillary column are discussed.  相似文献   
997.
EEG power spectral analysis was studied from 14 (alumina-gel) chronically epileptic, undrugged monkeys during an EEG operant conditioning experiment. The composite profile of the average epileptic monkey shows the majority of power to be below 10 Hz. Because of the large variance in the data, no significant changes in the EEG power spectra could be detected as a function of conditioning. The possible reasons for this large variance are discussed. Hypothesis from previous human "biofeedback" studies would allow the prediction that those frequencies corresponding to the mu and sensory-motor-rhythm should negatively covary with seizure frequency. Data from this study did not support such assertions. The method of using spectral analysis for quantifying changes in the EEG which covary with operant conditioning is evaluated.  相似文献   
998.
The role of microcomputers in the analytical laboratory is growing rapidly as applications software becomes more generally available. In this survey, the impact of microcomputers on the practice of analysis in pharmaceutical and biomedical areas is examined in the context of available hardware. The advent of 16-bit microcomputers and the implications of computer access to networked data bases are also discussed.  相似文献   
999.
Summary The activities of three plasma lysosomal hydrolases, -galactosidase, -glucuronidase and -N-acetylglucosaminidase, were studied in 20 workers exposed to metallic mercury vapor in a chlorine alkali plant and in 10 nonexposed referents. The urinary excretion and blood levels of mercury were determined on the day of study, and the history of mercury exposure was reviewed from the records of mercury concentrations in urine and blood over periods of up to 133 months. The average levels of -N-acetylglucosaminidase and -glucuronidase were higher in the plasma of exposed workers, but the difference was not significant. No significant positive correlation was seen between lyosomal enzyme activities and cumulative long-term exposure to mercury. It is concluded that measurement of plasma lysosomal hydrolase-activities is not of great value in the biological monitoring of workers exposed to low concentrations of metallic mercury vapor.In line with published data, the concentration of mercury showed a clearcut diurnal variation in nonexposed persons, persons currently exposed and persons with a history of past exposure. The excretion rate of mercury remained constant throughout the day.  相似文献   
1000.
Summary Due to a technical rule for dangerous agents (TRGS 410), issued by the Ministry of Labor in the Federal Republic of Germany in 1979, toxicological analyses in biological materials must be carried out under conditions of statistical quality control. This quality-control scheme provides internal and external control programmes. For internal quality control, the results of many years of experience with five commercially available control specimens and one home-made control have been evaluated. The control samples showed good, comparable results over a long period. Except in a few cases, there was good agreement between our results and the assigned values. Since 1982, the German Society of Occupational Medicine has offered eight intercomparison programmes for external quality. In samples from 80–90 laboratories, 6 metals in blood and around 20 inorganic and organic parameters in urine in 2 concentration adjustments have been analysed. Successful participation was certified if both results obtained for one parameter were within the tolerance range (assigned] value ± 3 SD). The average success rate was around 60%.  相似文献   
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