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Conflict Between Doctor and Patient   总被引:1,自引:0,他引:1  
"The belief that doctors can act on behalf of patients denies the existence of inevitable conflict." Jay Katz1  相似文献   
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The Scent Transfer Unit (STU-100) is a portable vacuum that uses airflow through a sterile gauze pad to capture a volatiles profile over evidentiary items for subsequent canine presentation to assist law enforcement personnel. This device was evaluated to determine its ability to trap and release organic compounds at ambient temperature under controlled laboratory conditions. Gas chromatography-mass spectrometry (GC-MS) analyses using a five-component volatiles mixture in methanol injected directly into a capture pad indicated that compound release could be detected initially and 3 days after the time of collection. Additionally, 15 compounds of a 39-component toxic organic gaseous mixture (10-1000 parts per billion by volume [p.p.b.(v)]) were trapped, released, and detected in the headspace of a volatiles capture pad after being exposed to this mixture using the STU-100 with analysis via GC-MS. Component release efficiencies at ambient temperature varied with the analyte; however, typical values of c. 10% were obtained. Desorption at elevated temperatures of reported human odor/scent chemicals and colognes trapped by the STU-100 pads was measured and indicated that the STU-100 has a significant trapping efficiency at ambient temperature. Multivariate statistical analysis of subsequent mass spectral patterns was also performed.  相似文献   
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The study investigates the presence of tetrahydrocannabinols in the head hair and the pubic and axillary hair. The hair samples were obtained from hashish smokers. The concentrations were determined by radioimmunoassay and reflect total tetrahydrocannabinols and metabolites. The values found ranged from 0.4 ng/mg hair up to 3.8 ng/mg hair. The presence of the drug in the hair samples was also demonstrated by GC/MS.  相似文献   
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A solid-phase microextraction-gas chromatographic-mass spectrometric (SPME-GC-MS) method has been developed and validated for measuring four club drugs in human urine. These drugs include gamma-hydroxybutyrate (GHB), ketamine (KET), methamphetamine (MAMP), and methylenedioxymethamphetamine (MDMA). These drugs are referred to as 'club drugs' because of their prevalence at parties and raves. Deuterium labeled internal standards for each of the four drugs was included in the assay to aid in quantitation. The drugs were spiked into human urine and derivatized using pyridine and hexylchloroformate to make them suitable for GC-MS analysis. The SPME conditions of extraction time/temperature and desorption time/temperature were optimized to yield the highest peak area for each of the four drugs. The final SPME parameters included a 90 degrees C extraction for 20min with a 1min desorption in the GC injector at 225 degrees C using a splitless injection. All SPME work was done using a 100microm PDMS fiber by Supelco. The ratio of pyridine to hexylchloroformate for derivatization was also optimized. The GC separation was carried out on a VF-5ht column by Varian (30m, 0.25mm i.d., 0.10microm film thickness) using a temperature program of 150-270 degrees C at 10 degrees C/min. The instrument used was a ThermoFinnigan Trace GC-Polaris Q interfaced with a LEAP CombiPal autosampler. The data was collected by using extracted ion chromatograms of marker m/z values for each drug from the total ion chromatograms (TIC) (full scan mode). Calibration curves with R(2)>0.99 were generated each day using the peak area ratios (peak area drug/peak area internal standard) versus concentration. The validated method resulted in intra-day and inter-day precision (% R.S.D.) of less than 15% and a % error of less than 15% for four concentrations in the range of 0.05-20microg/mL (MAMP) and 0.10-20microg/mL (GHB, KET, and MDMA). This method has the advantage of an easy sample preparation with acceptable accuracy and precision for the simultaneous quantification of these four drugs of abuse and shows no interference from the urine matrix.  相似文献   
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Mara Salvatrucha (MS‐13), founded in 1980s Los Angeles by Salvadoran immigrant youth, is today one of the largest street gangs in North and Central America. In recent years the group has acquired a reputation for extreme brutality and has ostensibly mutated into a fast‐expanding, transnational organized crime network with possible ties to international terrorists. Drawing on key concepts in gang research and multiple methodological tools, this article seeks to sharpen understanding of MS‐13's structure and activities. While the group is active in many countries, it is transnational only in a symbolic manner, not in its configuration or span of authority. Impelled largely by Central American gang‐suppression policies, MS‐13 has evolved from a traditional street gang into a group with organized crime characteristics, but it remains a social phenomenon rooted in urban marginality. Ultimately, a more nuanced picture of Mara Salvatrucha can inform the search for more effective gang policies.  相似文献   
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