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OBJECTIVE: To compare the detection and scoring of erosions in patients with rheumatoid arthritis (RA) using magnetic resonance (MR) and multidetector helical computerized tomographic (CT) scanning. METHODS: Comparative CT and MR scans of the dominant wrist were obtained from 9 patients with RA and clinical examination was performed to assess disease activity. MR and CT scans were scored for erosions and MR scans for bone edema by 2 radiologists using a validated system. Radiographs of the hands and feet were also scored for erosions using the modified Sharp score. RESULTS: In 117 of 135 (87%) sites there was concordance for erosions between MR and CT scans. At the remaining 18/135 sites (13%), erosions were identified by CT but not MR in 12/135 (9%) and by MR but not CT in 6/135 (4%). Partial volume artefacts on MR images and shifts in slice position were the most common reasons for erosion mismatch between MR and CT. The mean CT bone erosion score was significantly higher than the MR erosion score when individual bony sites were examined (p = 0.024), with the greatest difference being at the metacarpal bases. The total bone erosion score also tended to be higher on CT than MR [median scores of 20 (range 0-66) and 12 (0-51), respectively; p = 0.060]. MR and CT erosion scores correlated strongly with the total Sharp score (r = 0.93, p = 0.0002 and r = 0.94, p = 0.0002, respectively) and with the Disease Activity Score (MR: r = 0.77, p = 0.02; CT: r = 0.71, p = 0.03). CONCLUSION: Most erosions were detected using both modalities, but erosion scores were higher on CT than MR scans, especially at the metacarpal bases. It is possible that small erosions in some regions are more easily detected by CT because of its ability to clearly delineate cortical bony margins.  相似文献   
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Background

There is no established primary care solution for the rapidly increasing numbers of severely obese people with body mass index (BMI) > 40 kg/m2.

Aim

This programme aimed to generate weight losses of ≥15 kg at 12 months, within routine primary care.

Design and setting

Feasibility study in primary care.

Method

Patients with a BMI ≥40 kg/m2 commenced a micronutrient-replete 810–833 kcal/day low-energy liquid diet (LELD), delivered in primary care, for a planned 12 weeks or 20 kg weight loss (whichever was the sooner), with structured food reintroduction and then weight-loss maintenance, with optional orlistat to 12 months.

Result

Of 91 patients (74 females) entering the programme (baseline: weight 131 kg, BMI 48 kg/m2, age 46 years), 58/91(64%) completed the LELD stage, with a mean duration of 14.4 weeks (standard deviation [SD] = 6.0 weeks), and a mean weight loss of 16.9 kg (SD = 6.0 kg). Four patients commenced weight-loss maintenance omitting the food-reintroduction stage. Of the remaining 54, 37(68%) started and completed food reintroduction over a mean duration of 9.3 weeks (SD = 5.7 weeks), with a further mean weight loss of 2.1 kg (SD = 3.7 kg), before starting a long-term low-fat-diet weight-loss maintenance plan. A total of 44/91 (48%) received orlistat at some stage. At 12 months, weight was recorded for 68/91 (75%) patients, with a mean loss of 12.4 kg (SD = 11.4 kg). Of these, 30 (33% of all 91 patients starting the programme) had a documented maintained weight loss of ≥15 kg at 12 months, six (7%) had a 10–15 kg loss, and 11 (12%) had a 5–10 kg loss. The indicative cost of providing this entire programme for wider implementation would be £861 per patient entered, or £2611 per documented 15 kg loss achieved.

Conclusion

A care package within routine primary care for severe obesity, including LELD, food reintroduction, and weight-loss maintenance, was well accepted and achieved a 12-month-maintained weight loss of ≥15 kg for one-third of all patients entering the programme.  相似文献   
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ObjectiveThis study aimed to assess the effect of different storage media on the hardness and monomer elution of CAD/CAM composite blocks.MethodsFive resin-composite blocks (RCB), one polymer-infiltrated ceramic network (PICN) block (Enamic (EN)), one ceramic-filled poly ether ether ketone (PEEK) block (Dentokeep (DK)), and one feldspathic ceramic block. Microhardness was measured using a Vickers indenter tester (FM-700, Future Tech Corp., Japan). In addition 4 conventional resin-composites were investigated for monomer elution using high performance liquid chromatography (HPLC) after storage in different media for 3 months. The data were analysed by three-way ANOVA, two-way ANOVA, one-way ANOVA, Tukey’s post hoc test and the independent t-test (α = 0.05 for all tests).ResultsThe specimens stored in the water had a hardness reduction ranging from 0.9% to 24.4%. In artificial saliva, the specimens had a hardness reduction ranging from 2.8% to 23.2%. The hardness reduction percentage in 75% Ethanol/Water (E/W) ranged between 3.8% and 35.3%. All materials, except GR (resin-composite block) and DK (Polyetheretherketone (PEEK)), showed a variable extent of monomer elution into 75% E/W with significantly higher amounts eluted from conventional composites. GRA and GND (conventional resin-composites) eluted TEGDMA in artificial saliva and GRA eluted TEGDMA in water.SignificanceThe hardness of CAD/CAM composite blocks was affected by different storage media, and they were not as stable as ceramic, with PICN exhibited superior hardness stability to all of the resin-composite blocks in all the storage media and was comparable to ceramic block. The hardness reduction percentage of the CAD/CAM composite blocks was influenced by the filler loading and resin-matrix composition.Minimal or no monomer elution from CAD/CAM blocks was detected.  相似文献   
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Background. This study used Item Response Theory (IRT) to model the psychometric properties of a Theory of Mind (ToM) stories task. The study also aimed to determine whether the ability to understand states of false belief in others and the ability to understand another's intention to deceive are separable skills, and to establish which is more sensitive to the presence of paranoia.

Method. A large and diverse clinical and nonclinical sample differing in levels of depression and paranoid ideation performed a ToM stories task measuring false belief and deception at first and second order.

Results. A three-factor IRT model was found to best fit the data, consisting of first- and second-order deception factors and a single false-belief factor. The first-order deception and false-belief factors had good measurement properties at low trait levels, appropriate for samples with reduced ToM ability. First-order deception and false beliefs were both sensitive to paranoid ideation with IQ predicting performance on false belief items.

Conclusions. Separable abilities were found to underlie performance on verbal ToM tasks. However, paranoia was associated with impaired performance on both false belief and deception understanding with clear impairment at the simplest level of mental state attribution.  相似文献   
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