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991.

Purpose:

To evaluate whether perfusion fraction (PF) calculated with diffusion‐weighted magnetic resonance imaging (MRI) predicts the presence of blood supply in ovarian masses.

Materials and Methods:

PFs of 92 ovarian lesions in 53 patients administered gadolinium were retrospectively calculated with diffusion‐weighted images at b‐values of 0, 500, and 1000 sec/mm2. PFs were compared between ovarian lesions, except for fat, with (n = 21) or without contrast enhancement (n = 57), using Student's t‐test and receiver operating characteristics (ROC) curve analysis. Lesion enhancement rates of contrast‐enhanced images at 30 and 180 seconds after gadolinium injection (ER30sec and ER180sec) and PFs were compared using Pearson's correlation coefficient.

Results:

PFs of the lesions with contrast enhancement were significantly higher than those without contrast enhancement (0.22 ± 0.09 and 0.02 ± 0.08, respectively, P < 0.0001). The ROC curve identified the best cutoff point for PF at 0.135 (95.2% sensitivity and 94.7% specificity) as a predictor of the contrast enhancement effect. The area under the ROC curve was 0.984. PF correlated moderately with ER30sec (0.62, y = 0.13x + 0.04, P < 0.0001) and ER180sec (0.74, y = 0.13x + 0.03, P < 0.0001).

Conclusion:

PF calculated with diffusion‐weighted images can potentially predict blood supply in ovarian masses. J. Magn. Reson. Imaging 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
992.
We evaluated the results of proximal row carpectomy (PRC) for unreduced perilunate dislocation in 6 patients. The average period from the injury to the operation was 24 weeks. The modified Mayo wrist score was used for clinical evaluation. Radiological evaluation was based on the radius-capitate alignment. Pain disappeared in 4 cases; mild pain during activity persisted in 2 cases. The average flexion-extension are was 59% of the values on the unaffected side. The average grip strength was 72% of the unaffected side, and the average modified Mayo wrist score was 71 points. Three patients showed favourable radius-capitate alignment, while the other 3 patients showed poor radius-capitate alignment on the radiographs. The postoperative radius-capitate alignment was related to the preoperative position of the capitate on the lateral view. Those with poor radius-capitate alignment tended to obtain lower scores compared to those with favourable alignment.  相似文献   
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BackgroundMajor reasons for long-term care insurance certification in Japan are stroke, dementia, and fracture. These diseases are reported to be associated with calcium intake. This study examined the association between calcium intake and impaired activities of daily living (ADL) using the data from NIPPON DATA90, consisting of representative sample of the Japanese population.MethodsA population-based nested case-control study was performed. A baseline survey was conducted in 1990, followed by ADL surveys of individuals ≥65 years old in 2000. Individuals with impaired ADL and selected age- and sex-matched controls were then identified. We obtained 132 pairs. Calcium intake was energy-adjusted using the residual method. The association between calcium intake and impaired ADL was examined using conditional logistic regression models. To assess the accuracy of the estimates, we conducted bootstrap analyses.ResultsThe adjusted odds ratios (ORs) for impaired ADL compared with the group with a calcium intake of <476 mg/day were 0.72 (95% confidence interval [CI], 0.37–1.40) for the 476–606 mg/day group and 0.44 (95% CI, 0.21–0.94) for the ≥607 mg/day group in 2000 (P for linear trend = 0.03). After the bootstrap analyses, the inverse relationship unchanged (median OR per 100-mg rise in calcium intake, 0.87 [1,000 resamplings]; 95% CI, 0.76–0.97).ConclusionsAfter bootstrap analyses, calcium intake was inversely associated with impaired ADL 10 years after the baseline survey.Key words: bootstrap analyses, calcium intake, impaired activities of daily living, nested case-control study, NIPPON DATA90  相似文献   
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Background

Poststroke gait disorders negatively impact activities of daily living. Rehabilitation for stroke patients is aimed at improving their walking ability, balance, and quality of life. Robot-assisted gait training (RAGT) is associated with an increased number of task-specific exercises, which may benefit poststroke motor learning. We investigated the effects of RAGT using Stride Management Assist (SMA, which increases walk ratio by inducing hip-joint flexion and extension) in subacute stroke patients with hemiplegia.

Methods

We conducted a single center, open-label randomized controlled trial in hemiplegia patients who experienced a first ever stroke and were admitted to the convalescent rehabilitation ward. A total of 41 were divided into the control (20 patients) and experimental group (21 patients). A 10-day, conventional gait training program was carried out for the control group; and RAGT with SMA was used for the experimental group. The maximum walking speed and other gait parameters were compared preintervention and postintervention. The intergroup differences in the improvement ratio were compared using an intention-to-treat analysis.

Results

Ten-day intervention was completed by 36 patients. There was no difference between the 2 groups regarding gait parameters at intervention initiation. The improvement ratio of the maximum walking speed was significantly higher for the experimental group. Significant improvements were observed postintervention for maximum walking speed, paralysis-side step length, symmetry, and cadence in the experimental group. No adverse events attributable to the SMA were observed.

Conclusions

Ten days of RAGT with the SMA was effective for improving gait disorders of subacute stroke patients.  相似文献   
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