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991.
992.

Purpose

This study aimed to evaluate whether histogram analysis of the apparent diffusion coefficient (ADC) of a solid tumor component could distinguish borderline ovarian tumors from ovarian carcinoma.

Materials and methods

Sixteen pathologically proven borderline tumors and 21 carcinomas were retrospectively examined. Magnetic resonance (1.5-T) image data sets were coregistered, and the solid components of each tumor were semiautomatically segmented. ADC histograms of the solid components were extracted; modes, minimums, means, and 10th, 25th, 50th, 75th, and 90th percentiles of the histograms were compared between the two tumor types, and receiver-operating characteristic (ROC) analysis was performed.

Results

The mode, minimum, mean, 10th, 25th, 50th, and 75th percentile ADC values of solid components of borderline tumors were significantly larger than those of carcinomas. Among these, the 10th percentile values had the lowest p value (p = 0.0003). At ROC analysis, the area under the curve (AUC) in the 10th percentile was the greatest (0.854), and the best cutoff value in the 10th percentile provided the highest specificity (93.8 %).

Conclusions

ADC histograms of solid tumor components facilitated the distinction between borderline ovarian tumors and carcinoma. The 10th percentile ADC values had the best diagnostic performance.
  相似文献   
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Hidden harm     
Suzuki M  Konno C  Takahashi S  Uchiyama M 《Lancet》2011,377(9768):874
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997.
The intestinal epithelial cells(IECs) form a selective permeability barrier separating luminal content from underlying tissues.Upon injury,the intestinal epithelium undergoes a wound healing process.Intestinal wound healing is dependent on the balance of three cellular events;restitution,proliferation,and differentiation of epithelial cells adjacent to the wounded area.Previous studies have shown that various regulatory peptides,including growth factors and cytokines,modulate intestinal epithelial wound hea...  相似文献   
998.
Corticothalamic projection neurons in the cerebral cortex constitute an important component of the thalamocortical reciprocal circuit, an essential input/output organization for cortical information processing. However, the spatial organization of local excitatory connections to corticothalamic neurons is only partially understood. In the present study, we first developed an adenovirus vector expressing somatodendritic membrane-targeted green fluorescent protein. After injection of the adenovirus vector into the ventrobasal thalamic complex, a band of layer (L) 6 corticothalamic neurons in the rat barrel cortex were retrogradely labeled. In addition to their cell bodies, fine dendritic spines of corticothalamic neurons were well visualized without the labeling of their axon collaterals or thalamocortical axons. In cortical slices containing retrogradely labeled L6 corticothalamic neurons, we intracellularly stained single pyramidal/spiny neurons of L2-6. We examined the spatial distribution of contact sites between the local axon collaterals of each pyramidal neuron and the dendrites of corticothalamic neurons. We found that corticothalamic neurons received strong and focused connections from L4 neurons just above them, and that the most numerous nearby and distant sources of local excitatory connections to corticothalamic neurons were corticothalamic neurons themselves and L6 putative corticocortical neurons, respectively. These results suggest that L4 neurons may serve as an important source of local excitatory inputs in shaping the cortical modulation of thalamic activity.  相似文献   
999.
We aimed to study whether either [123l] myocardial meta-iodobenzylguanidine (MIBG) myocardial scintigraphy or the odor stick identification test for Japanese (OSIT-J) is effective in differentiating Parkinson’s disease (PD) from multiple system atrophy (MSA). We compared the MIBG accumulation and olfactory score between 42 PD and 42 MSA (19 MSA-P and 23 MSA-C) patients in the early stages. [123l] MIBG myocardial scintigraphy showed higher sensitivity and the olfactory test higher specificity in differentiating PD from MSA. There were significant differences between PD and MSA-C (p = 0.0019) instead of MSA-P (p > 0.05) in the MIBG accumulation, while there were significant differences between PD and MSA-P (p = 0.0003) or MSA-C (p = 0.0003) in the OSIT-J score. Our data suggest that the olfactory test can be useful as a clinical tool with its higher specificity in differentiating PD from MSA in the early stages and, moreover, support the discrimination of PD from MSA-P.  相似文献   
1000.
We recently developed a telemetry system for recording neural activity in the brains of unrestrained pigs. To test the fidelity of waveform reproduction, we compared local field potentials in the temporal hippocampus of six pigs by simultaneous recording with a cable system. We analyzed differences between the telemetry and cabled data filtered through a low-cut filter at 1, 4, or 30 Hz. Analysis of 10,000 data recorded while pigs were lying down showed a higher correlation with low-cut filtering at 4 or 30 Hz than at 1 Hz. Over 97% of differences in amplitude between the telemetry and cable data lay within the 95% confidence interval. Measurements were reproducible. A box plot of the differences clearly showed increased data symmetry and reduced skewness by low-cut filtering at 4 or 30 Hz. Almost the same results were obtained in two animals during feeding. Thus, the local field potentials in the temporal hippocampus were telemetered with almost the same accuracy as by cable measurement during both resting and feeding. However, artifacts in the first 100 ms (low-cut filtering at 1 or 4 Hz) or 5 ms (30 Hz) of measurements had to be removed for analysis.  相似文献   
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