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31.
Diagnosis of fetal isolated mild ventriculomegaly (IMVM) is the most common brain abnormality on prenatal ultrasound. We have set to identify potential alterations in brain development specific to IMVM in tissue volume and cortical and ventricular local surface curvature derived from in utero magnetic resonance imaging (MRI). Multislice 2D T2-weighted MRI were acquired from 32 fetuses (16 IMVM, 16 controls) between 22 and 25.5 gestational weeks. The images were motion-corrected and reconstructed into 3D volumes for volumetric and curvature analyses. The brain images were automatically segmented into cortical plate, cerebral mantle, deep gray nuclei, and ventricles. Volumes were compared between IMVM and control subjects. Surfaces were extracted from the segmentations for local mean surface curvature measurement on the inner cortical plate and the ventricles. Linear models were estimated for age-related and ventricular volume-associated changes in local curvature in both the inner cortical plate and ventricles. While ventricular volume was enlarged in IMVM, all other tissue volumes were not different from the control group. Ventricles increased in curvature with age along the atrium and anterior body. Increasing ventricular volume was associated with reduced curvature over most of the ventricular surface. The cortical plate changed in curvature with age at multiple sites of primary sulcal formation. Reduced cortical folding was detected near the parieto-occipital sulcus in IMVM subjects. While tissue volume appears to be preserved in brains with IMVM, cortical folding may be affected in regions where ventricles are dilated.  相似文献   
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A healthy diet and good eating behaviors are essential components of long-term success in weight maintenance after bariatric surgery. Although rates of revised bariatric surgery have increased, data on subsequent behavioral outcomes are sparse. The aim of our study was to investigate behavioral outcomes following revised laparoscopic sleeve gastrectomy (R-LSG) that was indicated for failed laparoscopic adjustable gastric banding and compare with outcomes following primary laparoscopic sleeve gastrectomy (P-LSG). Twelve patients who underwent R-LSG and 25 patients who underwent P-LSG between 2007 and 2009 in our medical center completed a questionnaire that assessed weight loss, eating behaviors, physical activity, food tolerance, and satisfaction. The average time elapsed since the operation was 18 months for both groups. In the R-LSG group, more patients reported non-normative eating patterns and less healthy food selection than in the P-LSG group. Food tolerance and satisfaction were also lower after R-LSG. Engagement in regular physical activity increased from 0 to 16.7 % in the R-LSG group and from 8 to 33 % in the P-LSG group. After R-LSG, 58 % reported eating at scheduled times, compared with 85 % after P-LSG. Levels of healthy food selection, food tolerance, normative eating patterns, and physical activity were lower in the R-LSG group than in the P-LSG group. This study highlights the need to develop pre- and post-surgery treatment that would promote better behavioral outcomes in the growing number of individuals undergoing repeat bariatric surgery.  相似文献   
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ObjectivesTo determine the effect of prostate volume on the diagnostic yield of prostate biopsies.Materials and methods155 consecutive patients underwent 12-core transrectal ultrasound guided needle biopsies. Data were collected prospectively on age, serum PSA, digital rectal examination (DRE), previous prostate biopsies, prostate volume and pathologic result. Univariate and multivariate logistic regressions were undertaken to determine the effect of prostate volume on the risk for a positive biopsy.Results45 patients (29%) were diagnosed with cancer. The median patient age was 63 (range 48–82) years, the median PSA level was 6.7 ng/ml (0.5–156 ng/ml), and the median prostate volume was 57 ml (16–273 ml). 42 patients (27%) had an abnormal DRE and 51 (33%) had undergone previous prostate biopsies. Positive biopsy rates were 39%, 33%, and 14% for prostate volume below 46 ml, between 45 and 73 ml, and above 72 ml, respectively. Univariate analysis showed that age, serum PSA, DRE and prostate volume were all associated with a positive biopsy. Multivariate analysis adjusted for age, PSA and DRE showed a significant risk increase for a positive biopsy in smaller prostates. (OR = 5.6 95% CI 1.75–17.89; and 8.86 95% CI 2.72–28.82, for prostate volume between 45 and 72 ml and below 45 ml, respectively).ConclusionThe diagnostic yield of prostate biopsies is significantly lower in large prostates. As the result the standard 12-core biopsy may be insufficient for the diagnosis of cancer in large prostates.  相似文献   
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Considering the multi-etiological character of Alzheimer's disease (AD), the current pharmacological approaches using drugs oriented towards a single molecular target possess limited ability to modify the course of the disease and thus, offer a partial benefit to the patient. In line with this concept, novel strategies include the use of a cocktail of several drugs and/or the development of a single molecule, possessing two or more active neuroprotective-neurorescue moieties that simultaneously manipulate multiple targets involved in AD pathology. A consistent observation in AD is a dysregulation of metal ions (Fe2+, Cu2+ and Zn2+) homeostasis and consequential induction of oxidative stress, associated with beta-amyloid aggregation and neurite plaque formation. In particular, iron has been demonstrated to modulate the Alzheimer's amyloid precursor holo-protein expression by a pathway similar to that of ferritin L-and H-mRNA translation through iron-responsive elements in their 5′UTRs. This review will discuss two separate scenarios concerning multiple therapy targets in AD, sharing in common the implementation of iron chelation activity: (i) novel multimodal brain-permeable iron chelating drugs, possessing neuroprotective-neurorescue and amyloid precursor protein-processing regulatory activities; (ii) natural plant polyphenols (flavonoids), such as green tea epigallocatechin gallate (EGCG) and curcumin, reported to have access to the brain and to possess multifunctional activities, such as metal chelation-radical scavenging, anti-inflammation and neuroprotection.  相似文献   
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Background: Service-learning (SL) is commonly used in Occupational Therapy (OT) programs worldwide as a community placement educational strategy. However, most SL models are not clearly defined in terms of both methodology and learning outcomes.

Objectives: This longitudinal study explores a structured model of Service-Learning (Interpersonal Social Responsibility-Service Learning: ISR-SL) aimed towards the development of professional identity among OT students. Based on OT students experiences from the end of the course through later stages as mature students and professionals.

Material and methods: A qualitative research design was used to explore the perceptions and experiences of 150 first, second, and third-year OT students and graduates who have participated in ISR-SL during their first academic year.

Results: Our findings suggest that the structured, long-term relationship with a person with a disability in the natural environment, which is the core of the ISR-SL, allowed students to develop a professional identity based on seeing the person as a whole and recognizing his/her centrality in the therapeutic relationship.

Conclusions and significance: This study suggests ISR-SL as future direction or next step for implementing SL in OT and other healthcare disciplines programs.  相似文献   

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AIM: To evaluate the relationship among alveolar bone loss (ABL), bone status and calcium-regulating hormones in liver transplantees. PATIENTS AND METHODS: Twenty-one liver transplantees underwent a full oral examination. The correlations among bone densitometry, bone metabolic status and drug treatment were examined. RESULTS: Twelve patients had osteopenia, and six were osteoporotic. ABL was 4.33+/-2.32 mm (range 0.67-9.92). Parathyroid hormone (PTH) levels ranged from 14 to 106 (mean 55.2+/-26.4). The mean 25(OH)D(3) was 11.68+/-4.7, range 3.5-21.1 ng/ml. Nine patients were vitamin D deficient (<10 ng/ml); none of the patients had 25(OH)D(3) levels > or =30 ng/ml. No correlation was found between ABL and current or total glucocorticoids dose, although there was an inverse relation with the duration of treatment (r =-0.474, p=0.03). A positive correlation was found between ABL, PTH (r =0.419, p=0.059) and hip bone mineral density (BMD) (r=0.482, p=0.027). ABL correlated closely with age, PTH, glucocorticoid treatment (duration) and hip BMD (r =0.810, p=0.004). CONCLUSIONS: The majority of liver transplant patients had insufficient 25(OH)D(3) serum levels. Changes in calcium-regulating hormones and hip BMD were correlated with ABL. Therefore, therapeutic intervention aimed at treating vitamin D deficiency and secondary hyperparathyroidism should be considered in these patients. The benefits of vitamin D treatment in the management of secondary hyperparathyroidism and possible decrease in ABL deserve further evaluation in controlled trials.  相似文献   
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The aims of this study were to investigate whether introducing an interphase interval (IPI) to biphasic pulses during stimulation of the dorsiflexor muscles would affect force production and to determine whether the IPI effect is dependent on electrode position. Twelve healthy volunteers participated in the study. Each subject participated in one session during which electrically induced contraction (EIC) forces of the ankle dorsiflexors were measured with five different IPI settings ranging from 0 to 400 μs. Forces of EICs were assessed with the electrodes placed either with the proximal electrode positioned over the common peroneal nerve and the second electrode over the dorsiflexor muscles or with both electrodes located over the dorsiflexor muscles. The order of electrode placements and of the different IPI settings was randomized across subjects. The results indicated that the introduction of a 100‐μs‐long IPI may enhance force production when one electrode is located over the common peroneal nerve. However, increasing the duration of the IPI beyond 100 μs did not result in further increase in force production. In contrast, the introduction of an IPI did not increase force production when both electrodes were located over the dorsiflexor muscles. These findings may help to optimize stimulation settings during functional electrical stimulation to prevent foot‐drop.  相似文献   
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