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61.
PURPOSE: The use of gefitinib, the first drug approved to inhibit the epidermal growth factor receptor tyrosine kinase, is indicated in patients with non-small-cell lung cancer with tumors progressive after chemotherapy. The unique mechanism of action of this agent leads to distinctive patterns of response and toxicity in persons with lung cancer. Many of the principles of management relevant to gefitinib are distinct from those with conventional cytotoxic drugs. To meet this need, we present practical guidelines on the use of gefitinib in patients with non-small-cell lung cancer. METHODS: This article reviews gefitinib's indications, dosing, response phenomena, and patterns of relapse in individuals with radiographic response. RESULTS: We present our recommendations for the management of rash and diarrhea caused by this agent. CONCLUSION: This information can guide practitioners and help them inform their patients about what to expect when they receive gefitinib.  相似文献   
62.
Associations between street connectivity and active transportation   总被引:1,自引:0,他引:1  

Background  

Past studies of associations between measures of the built environment, particularly street connectivity, and active transportation (AT) or leisure walking/bicycling have largely failed to account for spatial autocorrelation of connectivity variables and have seldom examined both the propensity for AT and its duration in a coherent fashion. Such efforts could improve our understanding of the spatial and behavioral aspects of AT. We analyzed spatially identified data from Los Angeles and San Diego Counties collected as part of the 2001 California Health Interview Survey.  相似文献   
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Background  

Exercise has been recommended for improving global-well being in adults with fibromyalgia. However, no meta-analysis has determined the effects of exercise on global well-being using a single instrument and when analyzed separately according to intention-to-treat and per-protocol analyses. The purpose of this study was to fill that gap.  相似文献   
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PURPOSE: Videofluorography (VF) and endoscopy are commonly used for dynamic imaging (DI) of pharyngeal swallowing but do not offer transverse plane (TP) information. The aim of the present study was to evaluate helical computerized tomography (HCT) to measure the DI capability pharyngeal swallowing in the TP. METHODS: The HCT scan technique used was a single-slice cine mode with scan times of 100 ms. All 15 subjects were studied supine during dry swallow, swallowing of barium sulphate jelly and 3, 10, 15 or 20 ml of a 40% barium sulphate solution. Nine subjects repeated the test twice at more than 1 week's interval to determine the test-retest reliability. RESULTS: Swallowing leads to closure of the vocal folds, pharyngeal constriction and narrowing of the piriform sinuses allowing jelly passage between the sinuses. Laryngeal elevation then occurs with the opening of the pharyngoesophageal segment (PES). Swallowing a bolus of 20 ml produced the maximum anteroposterior and transverse diameters as well as the maximum opening area of the PES. The test-retest intraclass correlation coefficients with liquid deglutition ranged from 0.86 to 0.98. CONCLUSIONS: This study shows that HCT enables visualization of TP of PES complementing VF or endoscopic swallowing studies.  相似文献   
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BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD.  相似文献   
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