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861.
862.
Intramyocardial small vessel abnormalities are not commonly recognized. The best known abnormality is fibromuscular dysplasia involving the sinoatrial or atrioventricular nodal arteries. Small vessel disease has been reported as an isolated cardiac anomaly in individuals with sudden death, and may also be associated with other cardiac conditions including hypertrophic cardiomyopathy and mitral valve prolapse. The nature of the association is unknown, and the mechanism causing sudden death is sometimes obscure. We describe pathological changes of the intramyocardial small vessels of three individuals with sudden death. Abnormalities involved small vessels at different levels. In all the cases, the abnormalities were thought to have caused or contributed to the individual's death. The possible mechanisms of this are discussed.  相似文献   
863.
864.
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.  相似文献   
865.
866.
867.
A growing body of research has linked exposure to violence to violent behavior, but few studies have examined the impact of the timing of exposure to violence on violent behavior among inner city, minority youth. Theoretical insights derived from developmental psychology and psychopathology (DPP) and Agnew’s general strain theory (GST) give contrasting accounts of whether exposure to violence has a short term or long term impact on violent behavior. Five waves of data collected from African American youth living in twelve high poverty inner city neighborhoods was used to examine how the timing of exposure to violence over a four year time period impacts year five violent behavior. Multivariate results support GST’s contention that more proximal exposure to violence has a larger impact on violent behavior. The theoretical and practical implications of the findings for adolescent development in high poverty settings are discussed.
Richard SpanoEmail:
  相似文献   
868.
869.
Cole  Richard L.; Kincaid  John 《Publius》2006,36(3):443-459
A 2006 trend survey found that Americans most often select localgovernment as giving them the most for their money, followedby the federal and state governments. African Americans aremost supportive of the federal government as giving them themost for their money; Hispanics are most supportive of localgovernment. As in many previous years, the local property taxwas viewed as the worst tax, followed by the federal incometax, state sales tax, and state income tax. Americans displayedreduced trust and confidence in the federal government; however,trust in all three spheres of government—federal, state,and local—dropped between 2004 and 2006, possibly reflectiveof the poor response of all governments to Hurricane Katrina.Analysis of surveys since 1972 reveals that there has been along-term decline in the public's support for the federal governmentand a corresponding increase in support of state and especiallylocal governments.  相似文献   
870.
In this paper, the authors use the Bush administration's management grades from the Program Assessment Rating Tool (PART) to evaluate performance budgeting in the federal government—in particular, the role of merit and political considerations in formulating recommendations for 234 programs in the president's fiscal year 2004 budget. PART scores and political support were found to influence budget choices in expected ways, and the impact of management scores on budget decisions diminished as the political component was taken into account. The Bush administration's management scores were positively correlated with proposed budgets for programs housed in traditionally Democratic departments but not in other departments. The federal government's most ambitious effort to use performance budgeting to date shows both the promise and the problems of this endeavor.  相似文献   
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