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11.
The effects of carbon monoxide and cyanide on the hepatic redox state and energy charge were investigated. Rats were used for the experiment under pentobarbital anesthesia. Immediately after laparotomy, a rat was placed in an animal chamber made of a transparent plastic box and exposed to a test gas for 3 min. Every test gas was produced in a gas chamber connected to the animal chamber with a flexible tube. HCN was produced from NaCN and H2SO4. In the CO inhalation experiment, various amounts of CO were introduced into the gas chamber. Immediately after an exposure, about 2 g liver was frozen in situ with a precooled clamp. Oozed blood from the wound surface was sampled. Concentrations of ATP, ADP, AMP, acetoacetate, and beta-hydroxybutyrate in hepatic mitochondria were determined, and the redox state and the energy charge were calculated. For cyanide as well as CO, significant negative correlations were found between the concentration in the blood and the redox state. The same held true for the energy charge. The redox state showed a slight increase at low concentrations of both gases; however, thereafter it began to decrease sharply with increases in concentrations. When concentrations of the toxicant in the blood reached certain levels, a kind of turning point, beyond which the redox state does not decrease any more, was observed. It was about 40% for HbCO and about 2.0 micrograms/ml for cyanide, and the points seemed to be related to the concentrations, beyond which cells are irreversibly damaged. On the other hand, the energy charge did not change at low concentrations. With an increase in toxicant concentrations, the energy charge decreased drastically. The rate of decrease in the energy charge became higher when blood concentrations exceeded certain levels. It was about 40% for HbCO and 2.0 micrograms/ml for cyanide. The presence of low levels of blood cyanide did not affect the relationship between the energy charge and the HbCO concentration.  相似文献   
12.
The purpose of this paper is to see how economic factors determine prices in the previously communist countries undergoing privatization. This does not concern the auctions of big state enterprises where the prices are found to be rigged. In this paper we estimate hedonic price functions based on a unique data set on auction prices of apartments in Moscow. We collected the data ourselves by attending the auctions and gathered data on the characteristics. We estimated the hedonic equations using a disequilibrium approach because no equilibrium prices were observed for large number of apartments that were withdrawn from the auction. We found that, as the privatization of residential housing was carried out, the hedonic price equations fit the data remarkably well.  相似文献   
13.
ABSTRACT

Few studies examine the role of friends in victims’ decisions to seek help from health professionals. This study used a sample of college students (N = 637) to examine the factors that may influence whether students would advise a friend to seek help from health professionals. After providing an open-ended response to a vignette, students answered a series of questions about formal support providers, attitudes toward women and rape victims, and their background. Findings suggest a gender divide on the advice given, and more students who responded to an acquaintance-rape scenario recommended that a victim contact health professionals in comparison to those whose scenario depicted an intimate partner rape. Implications are discussed, focusing on the role of friends and campus policy in minimizing the impacts of victimization.  相似文献   
14.
The measurement of the sound by the shock wave and the analysis of the natural frequencies were carried out for the authentic and five kinds of counterfeit 500-yen coins for the purpose of the quick and simple discrimination. Four peaks of natural frequencies were observed in the range of 5–20 kHz for authentic coins. On the other hand, only three peaks were observed for some kinds of the counterfeit coins. Four peaks were observed for other counterfeit coins, however the peaks were slightly shifted compared to those for authentic coins. These results show that the discrimination of the counterfeit coins from authentic ones can be realized by the examination of the natural frequencies. This method is quite useful for the simple screening of authentic and counterfeit coins.  相似文献   
15.
Diquat can be extracted with 1-butanol from high pH solution in the presence of several moderate reductants. The red colored reduced compound of diquat in water turns to a purple compound in 1-butanol. The absorption of the purple compound is 0.105 at 383 nm and 0.119 at 520 nm in 1 microgram diquat/ml 1-butanol. The latter value is a little higher than that of the red compound at 495 nm in water. The purple compound is much more stable than the red compound in water. More than 80% of 10 ppm diquat added can be extracted from serum, blood, tissues, urine and some drinks. The extraction with 1-butanol is useful for concentration of diquat contained in large volume. The lower limit of detection is 0.1 microgram/ml 1-butanol. Paraquat is insoluble in 1-butanol under the same condition. Therefore, this method is applicable for the determination of diquat when paraquat is also contained in the solution.  相似文献   
16.
A simple and rapid method for isolation of five butyrophenones with Sep-Pak C18 cartridges from human samples, and their wide-bore capillary gas chromatography (GC), are presented. The GC was made by both flame ionization and electron capture detections. The drugs contained in alkaline samples were directly applied to the cartridges and eluted with chloroform/isopropanol (9:1). The recoveries with use of the cartridges were excellent for most drugs in both urine and plasma samples. We can recommend the Sep-Pak C18 cartridges for isolation of butyrophenones because of simplicity and rapidity, and also wide-bore capillary GC because of high sensitivity and low decomposition of drugs during passage through the column.  相似文献   
17.
An infant fatality following accidental ingestion of ajmaline is described. Ajmaline was determined by thin-layer chromatography and infrared spectrophotometry, and quantitated by high performance liquid chromatography. The ajmaline concentration in blood was 5.5 micrograms/mL. The toxicological data relevant to the interpretation of case findings are presented.  相似文献   
18.
A simple and rapid method, for the isolation of eight triazine herbicides from human serum and urine, using Sep-Pak C18 cartridges is presented. After mixing with distilled water, serum and urine samples containing the herbicides, were loaded on Sep-Pak C18 cartridges and eluted with either chloroform only or chloroform/methanol (9:1). The herbicides were detected by capillary gas chromatography with both flame ionization detection (FID) and nitrogen-phosphorus detection (NPD). Separation of eight triazine herbicides from each other and from impurities was generally satisfactory with the use of a non-polar DB-1 capillary column. Recovery of most compounds was excellent for both chloroform and chloroform/methanol (9:1) as elution solvents. Backgrounds were cleaner and evaporation time was shorter for the chloroform only than for the chloroform/methanol (9:1). The NPD gave sensitivity more than 10-20 times higher than that of FID.  相似文献   
19.
Seven salivary polymorphic systems were studied using whole and parotid saliva from random Japanese individuals. The gene frequencies obtained were: Pa+ = 0.212, Pb1 = 1.000, Pb2 = 0, Pr1 = 0.763, Pr2 = 0.237, Db+ = 0.051, Pm+ = 0.409, Ph+ = 0.026 and Amy1v = 0.013, respectively. Based on these gene frequencies, the chances for exclusion of falsely alleged fathers were calculated. The chance of exclusion on the basis of five salivary polymorphic systems was 0.305. The combined chance of exclusion utilizing only blood, serum and red-cell enzyme polymorphic systems among the Japanese population was 0.919; however, by applying salivary polymorphic systems to the calculation, the total exclusion rose to 0.944.  相似文献   
20.
The genetic polymorphism of serum orosomucoid (ORM) was studied in 168 unrelated German individuals using isoelectric focusing followed by immunoprinting. Two new alleles, tentatively designated ORM1*14 and ORM2*13, were identified. The method was successfully applied to demonstrate ORM1 types in dried bloodstains. Each type of ORM1 was also correctly determined in bloodstains heated at 130 degrees C for 30 min. The results indicated that ORM1 is a new powerful genetic marker system for the grouping of bloodstains.  相似文献   
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