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1.
Buffered formalin solutions were added to spiked blood samples containing diazepam, phenytoin, carbon monoxide and cyanide to give formalin-whole blood solutions of 5 and 8%. Sections of liver positive for desipramine, phenobarbital and phenytoin were placed in separate 5 and 8% formalin-water solutions. The formalin-blood solutions were monitored daily for 30 days, while the fixed liver and formalin-water samples were analyzed once a week for 4 weeks. In the formalin-blood solutions losses were found for diazepam and phenytoin over the 30-day period of at least 41% and 33%, respectively. Cyanide detection was not possible immediately after the addition of formalin and the presence of carboxyhemoglobin was difficult to detect after 1 week. In the liver, losses of phenobarbital and desipramine were greater than 60% while phenytoin showed little change. This study has revealed that the drugs examined at toxic concentrations can be detected, with variable recoveries, for up to 30 days after fixation with formalin. However, quantitative analysis for cyanide and carboxyhemoglobin may be significantly impaired in the presence of formaldehyde.  相似文献   

2.
This paper describes the spectrophotometric determination of carboxyhemoglobin (CO-Hb) in blood on the basis of double wavelength spectrophotometry of absorbance difference. Absorbance measurements are made in the 500–600 nm region at a blood dilution of 100–200-fold. Blood is diluted with a solution containing Na2S2O4 to provide two components of CO-Hb and deoxyhemoglobin (deoxy-Hb). Absorbance difference at the two wavelengths at which deoxy-Hb has the same absorbance reflects only the CO-Hb component because the opposite component is nulled out of the mixture. After measurement of the absorbance difference, the measuring solution is saturated with CO gas to make all Hb derivative CO-Hb and remeasured at the same wavelengths. The percent of CO-Hb is considered the absorbance difference ratio. Results obtained by the present method was in satisfactory agreement with gas chromatographic data in blood not containing methemoglobin (Met-Hb). Comparative experiments using the gas chromatographic method and the present method were performed with samples containing Met-Hb. However, while there is a deficiency in the gas chromatographic method when the samples contain Met-Hb, the results of the present method were in close agreement with theoretical values when samples are mixed with CO-Hb, O2-Hb and Met-Hb. Advantages of this method are that it is simple and accurate, standard curve or equation for calculation and accurate dilution are not necessary.  相似文献   

3.
After self-administration of 0.05g of methamphetamine hydrochloride intravenously on three occasions at intervals of 3h, a 25-year-old female methamphetamine abuser ingested approximately 1.5 g of methamphetamine hydrochloride, and was found dead 3–4 h later. Complete rigor mortis was observed 1–2 h after death and the rectal temperature was 38.4°C 3–4 h after death.Distribution of methamphetamine and amphetamine in the body was analyzed by chemical ionization mass fragmentography. Amphetamine/methamphetamine concentrations (μ mol/100 g) were 0.2628.8 in blood, 0.6468.2 in brain, 0.96117.1 in liver, 0.5350.6 in kidney, and 1.491045 in stomach contents. Total amount of methamphetamine hydrochloride in stomach contents was 11.6mg.Amphetamine in tissues was a metabolite of methamphetamine, and amphetamine in stomach contents resulted from excretion into saliva and gastric mucous excretion. With rectal temperature at death estimated at more than 41°C, it would seem that hyperpyrexia played an important role in causing death from methamphetamine poisoning.  相似文献   

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A mathematical model to determine the maximum range of pellets fired from a shotgun has been suggested. It has been assumed that the air resistance experienced by a pellet is proportional to the square of its velocity (?μV2) where μ = AC with
C=0.061 86N13
and
A=1[17 696+2N+10 000(0.2?d)]
N is the number of pellets/ounce and d is the diameter of the pellets in inches. A method for calculating the maximum range has been suggested, and the values obtained for Buck 00, size 8 and size 9 American pellets are very close to the reported experimental observations. The maximum ranges for other sizes of pellets have also been calculated. The angle of projection decreases with increase in velocity and increases with increase in the weight of the pellet. It varies between 26° to 32° for common sizes of pellets and standard shotgun velocity. The maximum range in air is only 1 – 3% of the range attained by a pellet in vacuum.  相似文献   

6.
A 22-year-old male methamphetamine abuser was put under police protection owing to his abnormal state of excitation, but died 1 h later. Distribution of methamphetamine and amphetamine in the body was analyzed by the chemical ionization mass fragmentographic method. Amphetamine/methamphetamine concentrations (μmol/100 g) were 0.245.59 in blood, 0.419.43 in liver, 0.4110.02 in brain, 0.379.80 in kidney, 0.184.57 in muscle, 0.020.63 in subcutaneous fat and 1.871464 in gastric contents. Total amount of methamphetamine hydrochloride in stomach contents was about 54 mg. Amphetamine concentrations in tissues ranged from 3.2% to 4.3% of methamphetamine, and was 0.1% in stomach contents. Amphetamine in tissues seems to be a metabolite of methamphetamine, and amphetamine in gastric contents is presumed to result from gastric mucous excretion. The blood concentration of methamphetamine was at a fatal level, and the total amount of the drug in gastric contents indicates that fatal poisoning occurred by ingestion.  相似文献   

7.
This article details the stability of Delta(9)-tetrahydrocannabinol (THC) in oral fluid during collection, extraction and storage. Oral fluid is being increasingly used as the specimen of choice for the detection of drug use in various applications. Studies to determine the extraction efficiency of THC from the collection buffer and stability under various laboratory storage conditions were carried out. THC was extracted from the collection pad and buffer with an average efficiency over 80% and was stable in Quantisal oral fluid extraction buffer when stored at refrigerated temperatures. Fluorescent lighting caused THC losses of over 50%, however the presence of the pad reduced the loss. In the dark, the loss of THC at room temperature was approximately 20% over 14 days. When stored with the serum separators in place, THC losses were significant. After 3 days, THC concentration was reduced by almost 30%, and after 14 days, 60% of the drug was lost and the losses were not concentration dependent.  相似文献   

8.
There is a paucity of data available on the effect of storage on blood alcohol concentration (BAC) at elevated temperatures. Changes in serum alcohol concentration (SAC) and BAC were studied. Serum samples spiked with alcohol in the presence or absence of preservative were stored at 26.7 °, 32.2 ° or 37.8 °C respectively. Serum alcohol concentrations were determined daily on days 1 through 14, and on days 21 and 35. Under these controlled conditions, no significant change in SAC was observed at the aforementioned temperatures. Whole blood samples submitted from outside agencies were initially analyzed (day 1), then stored for 35 days at different elevated temperatures before a second analysis. The average loss in BAC was 19.20 ± 15.6, 9.95 ± 5.7, and 15.60 ± 6.9% when the samples were stored at 26.7, 32.2 and 37.8 °C, respectively. The alcohol loss from whole blood samples may be attributed to chemical oxidation rather than to elevated temperatures. It is, therefore, concluded that a whole blood sample obtained from a living individual and stored in a locker, glove compartment or other environment where the temperature is elevated, may lose 10–19% of its alcohol content over 35 days of storage. On the other hand, when a serum or plasma sample is exposed to the same environment, no significant change in SAC was observed. The utility of this information is significant to the forensic toxicologist. The results of this study suggest that a whole blood sample analyzed after exposure to elevated temperature may have had, originally, a higher BAC.  相似文献   

9.
The efficiency of a typing program for paternity testing concerns three specific aspects: first, what is the percentage of non-fathers that cannot be excluded from paternity; second, what is the percentage of true fathers that cannot be recognized as probable fathers, and third, what is the percentage of non-fathers that will be assigned as probale fathers. When extensive materials for observation with any specific typing program are not directly available, only the chance of non-exclusion of non-fathers can be calculated in a relatively simple way.The aim of the present study was to find a relationship between this and the other two criteria. It was found that the variance of the distribution of natural logarithms of paternity index values is approximated rather well by the formula var. I = 0.65 × (n(ln 1ne3)2) (n = the number of genetic systems of the typing program and ne = the chance of non-exclusion of non-fathers). This allows the estimation of the two other critical percentages: the percentage of true fathers that cannot be assigned, and the percentages: the percentage of true fathers that cannot be assigned, and the percentage of non-fathers that will be assigned as probably true fathers.  相似文献   

10.
For the determination of total hemoglobin (Hb) in blood containing elevated carboxyhemoglobin (COHb), a newly developed reagent containing a 100-fold concentration of ferricyanide (20 g/l) and a 2-fold concentration of Sterox SE was compared with a standard reagent (0.2 g/l ferricyanide), the reagent of van Kampen and Zijlstra, using forensic blood samples and experimentally heated blood samples. There were no significant differences between the spectra of hemiglobincyanide (HiCN) solution produced with our reagent and the van Kampen and Zijlstra reagent using experimentally heated blood samples. Although the spectra of HiCN changed gradually with increased heating time and with the passage of time after mixing, the absorbance at 540 nm (A540) did not change until at least 120 min for both the reagents. When forensic blood samples containing elevated COHb were mixed with the van Kampen and Zijlstra reagent, total-Hb concentrations determined 5 min after mixing were 10-20% higher than those determined after 180 min. The overestimates of total Hb determined after 5 min resulted in comparable underestimates of percentage saturation of COHb (COHb%) when COHb% was obtained from the ratio of COHb content, determined by gas chromatogrpahy, to total-Hb concentration in blood. However, there was an extremely good correlation between the values of total Hb in forensic blood samples determined with the van Kampen and Zijlstra reagent after 180 min and those determined with our reagent after 5 min. From the results obtained, our reagent proved to be suitable for the determination of total Hb in forensic science practice.  相似文献   

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An Alcolmeter Pocket Model breath alcohol device, based on an electrochemical (fuel cell) oxidation principle for ethanol analysis, has been evaluated under in vitro conditions. The result of a test is displayed on an analogue meter within 20 – 30 seconds after sampling; replicate tests may be made within 3 – 5 minutes. The electrochemical detector used was found to respond to acetaldehyde, methanol, isopropanol and n-propanol vapours besides ethanol, but it was insensitive to acetone vapour. The Alcolmeter response with a 0 – 2.0 mg/ml scale was linearly related to ethanol vapour concentration up to 1.0 mg/ml blood alcohol equivalent concentration; above this level the response was curvilinear, the Alcolmeter reading being too low. The standard deviation of an ethanol vapour determination in vitro was ±0.0175 mg/ml at a mean concentration of 0.902 mg/ml. The accuracy of the device expressed as percent recovery at 0.50, 1.0 and 1.4 mg/ml blood alcohol concentrations was 96.8%, 98.3%, and 88.3%, respectively. When the Alcolmeter was calibrated at 0.50 mg/ml and used occasionally each day over an 18-day period, the drop in initial calibration was 0.01 mg/ml per week.  相似文献   

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15.
The introduction of a standardized paternity index (PI) for the statistical evaluation of blood group findings in cases of disputed paternity is proposed and explained. By using the PI XY as parameter, it is not necessary to give the information of the probability of paternity in percent. The PI includes the full information of the blood group findings. In addition to that, by using the suggested standardization based on the probabilities of error according to Schulte Mönting and Walter the test volume is also taken into account. The interpretation of the mathematical result is given by verbal predicates, the limitations of which are orientated by the verbal predicates for the probabilities of error according to Schulte Mönting and Walter, published by us elsewhere. Besides the essential fact that the test volume is taken into account, the most important advantage of this procedure is that the mathematical result is involved in the court decision only by the PI (which is free of any valuation) and its verbal predicate and not by sometimes relatively high percentages, which may be misunderstood by laymen.  相似文献   

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A novel application of visible wavelength hyperspectral image analysis has been applied to determine the age of blood stains up to 30 days old. Reflectance spectra from selected locations within the hyperspectral image, obtained from a portable instrument, were subjected to spectral pre-processing. This was followed by the application of a linear discriminant classification model, making estimations possible with an average error of ± 0.27 days for the first 7 days and an overall average error of ± 1.17 days up to 30 days. This is also the first reported study of the determination of the age of fresh blood stains (less than one day old) with an error of ± 0.09 h. The studies have been made under controlled conditions and represent, at this stage, proof of concept results but also are the most accurate age estimation results for measurements between 0 and 30 days reported to date. The results are consistent with well-established kinetic processes suggesting that the pre-processing stages described are revealing spectroscopic changes which are reliably following the time dependent oxidation of HbO2. The potential for parameterisation of environmental factors to make the method generally applicable at crime scenes is discussed, along with the developments required to further improve classification and to make the instrument genuinely portable.  相似文献   

19.
Plasma leucine aminopeptidase (LAP) levels and respiration rates of isolated liver mitochondria were studied in carbon monoxide (CO)-poisoned rats sampled at respiratory arrest. An increase in LAP levels paralleled a decrease in the respiratory control ratio and the ADPO ratio. The results suggest that the damage to mitochondria closely correlates with the liver damage in rats during acute CO poisoning.  相似文献   

20.
A forensic application is reported for the sex determination of subjects whose dried bloodstains are analyzed by radioimmunoassay for testosterone and progesterone. Blood specimens of ten males and 15 females were collected, prepared as bloodstains, and then assayed at four-different time intervals for testosterone (T) and progesterone (P) contents up to 3 months later. The ratio of the two hormone contents (PT) was used to establish the sex origin of the dried blood specimens.  相似文献   

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