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951.
This study examines the dynamics of potentially violent encounters between police and public. It is based on systematic observation of about 350 eight-hour tours of duty by patrol officers in three precincts of New York City during the summer of 1986. It compares the tactics and resulting outcomes found in encounters handled, respectively, by patrol officers believed by their peers to be especially skilled at minimizing violence and a cross section of all other patrol officers. Its major conclusions are (1) violence, even verbal aggression, is relatively rare in police work: (2) most conflict is dampened by the arrival of the police, leaving little scope for the use of defusing tactics: and (3) the behavior of officers judged by colleagues to be skilled in minimizing violence is measurably different from the behavior of “average” patrol officers, and in ways that suggest that colleagues may be good judges of on-street performance.  相似文献   
952.
This paper describes a modified method of simultaneous quantitative determination of histamine and polyamines (putrescine, cadaverine, spermidine and spermine) in incised skin wounds of rats using high-performance liquid chromatography (HPLC) with a strong-cation exchange column, shim-pack ISC-05/S0504P, employing a linear gradient of 0.7-2.5 M sodium chloride. There was scarcely any change in the histamine content of the vital wounds throughout the one week experimental period, although content decreased slightly in 1-h-old wounds. On the other hand, concentrations of putrescine and spermidine increased suddenly 12 h after wounding, and spermine content increased slightly in 4-day-old wounds. There was no post-mortem change in the histamine, spermidine and spermine contents of vital wounds allowed to stand at 25 degrees C up to 24 h after death. Based on these results, this HPLC method may be useful for the determination of wound age during the period of healing.  相似文献   
953.
Intoxilyzer 5000 and blood-alcohol results from drivers arrested for operating a motor vehicle while intoxicated and for related offenses were compared during a two-year period. Three hundred and ninety-five pairs of results were studied. The breath- and blood-alcohol specimens in this study were collected within 1 h of each other. The mean blood-alcohol concentration obtained was 0.180 g/dL, with a range from zero to 0.338 g/dL. By comparison, the mean Intoxilyzer 5000 result was 0.16 g/210 L with a range from zero to 0.32 g/210 L. Compared with the blood-alcohol result, Intoxilyzer 5000 results were lower by more than 0.01 g/210 L 67% of the time, within 0.01 g/210 L 31% of the time, and higher by more than 0.01 g/210 L 2% of the time.  相似文献   
954.
To examine a possible relationship between pineal function and the sudden infant death syndrome (SIDS), samples of whole blood, ventricular cerebrospinal fluid (CSF) and/or vitreous humor (VH) were obtained at autopsy from 68 infants (45 male, 23 female) whose deaths were attributed to either SIDS (n = 32, 0.5-5.0 months of age; mean +/- S.E.M., 2.6 +/- 0.2 months) or other causes (non-SIDS, n = 36, 0.3-8.0 months of age 4.3 +/- 0.3 months). The melatonin concentrations were measured by radioimmunoassay. A significant correlation was observed for melatonin levels in different body fluids from the same individual. After adjusting for age differences, CSF melatonin levels were significantly lower among the SIDS infants (91 +/- 29 pmol/l; n = 32) than among those dying of other causes (180 +/- 27; n = 35, P less than 0.05). A similar, but non-significant trend was also noted in blood (97 +/- 23, n = 30 vs. 144 +/- 22 pmol/l, n = 33) and vitreous humor (68 +/- 21, n = 10 vs. 81 +/- 17 pmol/l, n = 15). These differences do not appear to be explainable in terms of the interval between death and autopsy, gender, premortem infection or therapeutic measures instituted prior to death. Diminished melatonin production may be characteristic of SIDS and could represent an impairment in the maturation of physiologic circadian organization.  相似文献   
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