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91.
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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TD Verstynen AM Weinstein WW Schneider JM Jakicic DL Rofey KI Erickson 《Psychosomatic medicine》2012,74(7):682-690
Objective Obesity and decreased physical health are linked to deficits in several cognitive domains. The broad range of cognitive problems linked to obesity suggests a global mechanism that may interfere with multiple neural systems. We examined how variation in body mass index (BMI) is associated with the microstructural integrity of fiber connections in the human brain. Methods White matter structure was measured using diffusion tensor imaging in 28 participants (mean age = 30 years) with BMI scores ranging from normal weight to obese (19.5-45.7 kg/m(2)) based on standard BMI criteria. Results Using a whole-brain voxelwise analysis, we found that, across participants, the fractional anisotropy of white matter voxels parametrically decreased with increasing BMI (63% of white matter voxels). Midbrain and brainstem tracts were among the pathways most strongly associated with obesity (r = -0.18 to -0.33, df = 27, all p values < .05). We also observed a weaker overall diffusion signal in individuals with higher BMI than controls with normal weight (r = -0.14 to -0.71, df = 27, for 67% of fiber pathways tested, all p values < .05). After controlling for this decrease in general diffusivity, we found that decreases in fractional anisotropy stemmed from both a decrease in axial diffusivity (p < .05) and an increase in radial diffusivity (p < .05). Conclusions Our results show that increased BMI is globally associated with a reduction in white matter integrity throughout the brain, elucidating a potential mechanism by which changes in physical health may influence cognitive health. 相似文献
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BackgroundRheumatoid arthritis is the most common chronic inflammatory disease in the UK. Serological status such as rheumatoid factor (RF) and anti-citrullinated peptide antibody (ACPA) positivity predict poor outcomes. Early intensive treatment regimens targeting remission reduce disease activity, structural damage, and long-term disability. However, we do not know whether all patients with active disease should have such intensive treatment regimens. Can serological status be used to predict the need for intensive therapy?MethodsWe analysed samples from a published randomised controlled trial which compared four treatment regimens in patients with early active rheumatoid arthritis (disease duration <2 years): methotrexate monotherapy, double therapy (methotrexate plus either ciclosporin or prednisolone), and triple therapy (methotrexate plus ciclosporin plus prednisolone). The trial randomised 467 patients (68% female, median age 54 years [IQR 46–63]). Disease activity was assessed with the disease activity score of 28 joints (DAS28). Remission was defined as DAS28 less than 2·6 at 24 months. RF isotypes (IgM and IgA) and ACPA levels were measured with commercial ELISA kits. Statistical analysis used Pearson's chi-squared test.Findings402 (86%) patients were positive for IgM RF, 346 (74%) for IgA RF, and 346 (74%) for ACPA. 98 (21%) patients achieved remission at 24 months. In RF IgM negative cases (n=65) the proportion of patients achieving remission at 24 months was similar in all treatment groups (25%, 22%, and 30% for monotherapy, double therapy, and triple therapy, respectively). In RF IgM positive cases, significantly fewer patients achieved remission with monotherapy (13/65, 17%) and double therapy (24/157, 15%) than with triple therapy (27/80, 34%) (p=0·001). There were similar, consistent findings with IgA RF and ACPA, with significantly more seropositive patients achieving remission with triple therapy than with monotherapy.InterpretationContemporary treatment of rheumatoid arthritis emphasises the use of intensive therapy to achieve remission. However, we have shown that not all patients require such an aggressive approach to therapy. Given the heterogeneity of the diease, treatment should be personalised to the individual, which would minimise costs of treatment as well as potentially toxic side-effects. Our study shows that only seropositive patients with rheumatoid arthritis should be given more intensive therapies.FundingNational Institute for Health Research. 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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