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Scintigraphy in 3 patients with chondroblastoma showed that the tumors were hyperemic and avidly accumulated the radionuclide. These changes were also present in adjacent normal bone, but to a lesser degree. This suggest that radionuclide uptake in chondroblastoma is a function of the blood supply to the tumor rather than primary matrix extraction. 相似文献
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The authors report a case of a hepatic artery aneurysm that simulated a mass in the head of the pancreas. The correct diagnosis was made preoperatively based on several findings: curvilinear calcification within the mass on CT, a well-defined cystic collection on ultrasound, absence of biliary duct dilatation or jaundice, and presence of other aneurysms. 相似文献
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Brandon DL. Marshall Evan Wood Jean A. Shoveller Jane A. Buxton Julio SG. Montaner Thomas Kerr 《Prevention science》2011,12(2):173-180
The purpose of this study was to determine the incidence and predictors of initiating methamphetamine injection among a cohort
of injection drug users (IDU). We conducted a longitudinal analysis of IDU participating in a prospective study between June
2001 and May 2008 in Vancouver, Canada. IDU who had never reported injecting methamphetamine at the study’s commencement were
eligible. We used Cox proportional hazards models to identify the predictors of initiating methamphetamine injection. The
outcome was time to first report of methamphetamine injection. Time-updated independent variables of interest included sociodemographic
characteristics, drug use patterns, and social, economic and environmental factors. Of 1317 eligible individuals, the median
age was 39.9 and 522 (39.6%) were female. At the study’s conclusion, 200 (15.2%) participants had initiated injecting methamphetamine
(incidence density: 4.3 per 100 person-years). In multivariate analysis, age (adjusted hazard ratio [aHR]: 0.96 per year older,
95%CI: 0.95–0.98), female sex (aHR: 0.58, 95%CI: 0.41–0.82), sexual abuse (aHR: 1.63, 95%CI: 1.18–2.23), using drugs in Vancouver’s
drug scene epicentre (aHR: 2.15 95%CI: 1.49–3.10), homelessness (aHR: 1.43, 95%CI: 1.01–2.04), non-injection crack cocaine
use (aHR: 2.06, 95%CI: 1.36–3.14), and non-injection methamphetamine use (aHR: 3.69, 95%CI: 2.03–6.70) were associated with
initiating methamphetamine injection. We observed a high incidence of methamphetamine initiation, particularly among young
IDU, stimulant users, homeless individuals, and those involved in the city’s open drug scene. These data should be useful
for the development of a broad set of interventions aimed at reducing initiation into methamphetamine injection among IDU. 相似文献
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Indoleamine 2,3-dioxygenase (IDO), a flavin-dependent enzyme that catalyzes the conversion of tryptophan to kynurenine, is induced in peripheral blood mononuclear cells by interferon-gamma (IFN gamma). Interleukin-4 (IL-4) is a cytokine that modulates the functional properties of monocytes/macrophages, and we investigated the effects of IL-4 on IDO. We showed that IL-4 inhibited the induction of IDO mRNA and IDO activity by IFN gamma in human monocytes. The inhibitory effect was evident with as little as 2 U/mL of IL-4. These results provide the first evidence that a cytokine can provide a negative signal for IDO expression and that IL-4 can influence the catabolism of tryptophan. 相似文献