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391.

Purpose  

The aim of this study was to investigate the diagnostic role of the apparent diffusion coefficient (ADC) measurement in the diagnosis of focal parenchymal lesions and to understand the discriminating role of the ADC value for differentiating Fasciola lesions from other focal liver lesions.  相似文献   
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TNF-related apoptosis-inducing ligand level in Alzheimer’s disease   总被引:1,自引:0,他引:1  
In the present study, we determined the significance of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in Alzheimer’s disease (AD). We characterized the expression of TRAIL protein in the cerebrospinal fluid (CSF) and serum with ELISA and TRAIL mRNA in the peripheral blood mononuclear cells (PBMCs) with real-time PCR in 22 patients with AD and 20 control cases. We could not find TRAIL protein in the CSF samples. The concentration of TRAIL protein in sera from patients with AD was not different from controls. However, there was an inverse correlation between serum TRAIL levels and Mini-Mental State Examination scores in AD patients. Also we did not find significant difference in TRAIL mRNA in the PBMCs of patients with AD when compared with control group. Our data indicate that TRAIL serum level decreases in the late stage of disease.  相似文献   
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RATIONALE AND OBJECTIVES: The objective of this work was to develop a quantitative method for improving lesion detection in dynamic contrast-enhanced magnetic resonance mammography (DCEMRM). For this purpose, we segmented and analyzed suspicious regions according to their contrast enhancement dynamics, generated a normalized maximum intensity-time ratio (nMITR) projection, and explored it to extract important features, to improve accuracy and reproducibility of detection. MATERIALS AND METHODS: A novel automated method is introduced to segment and analyze lesions in three dimensions. It consists of four consecutive stages: volume of interest selection, nMITR projection generation using a voxel sampling method based on a moving 3 x 3 mask, three-dimensional lesion segmentation, and feature extraction. The nMITR projection of the detected lesion is used to extract six features: mean, maximum, standard deviation, kurtosis, skewness, and entropy, and their diagnostic significance is studied in detail. High-resolution MR images of 52 breast masses from 46 women are analyzed using the technique developed. RESULTS: Entropy, standard deviation, and the maximum and mean value features were found to have high significance (P < 0.001) and diagnostic accuracy (0.86-0.97). The kurtosis and skewness were not significant. Automated analysis of DCEMRM using nMITR was shown to be feasible. CONCLUSION: The lesion detection method described is efficient and leads to improved, accurate, reproducible diagnoses. It is reliable in terms of observer variability and may allow for a better standardization of clinical evaluations. The findings demonstrate the usefulness of nMITR based features; nMITR-entropy shows the best performance for quantitative diagnosis.  相似文献   
398.

Purpose

The purpose of this study was to evaluate the best protocol to prepare endometrium for frozen embryo replacement (FER) cycles.

Methods

This study is a systematic review and meta-analysis. Following PubMed and OvidSP search, a total of 1166 studies published after 1990 were identified following removal of duplicates. Following exclusion of studies not matching our inclusion criteria, a total of 33 studies were analyzed. Primary outcome measure was live birth. The following protocols, including true natural cycle (tNC), modified natural cycle (mNC), artificial cycle (AC) with or without suppression, and mild ovarian stimulation (OS) with gonadotropin (Gn) or aromatase inhibitor (AI), were compared.

Results

No statistically significant difference for both clinical pregnancy and live birth was noted between tNC and mNC groups. When tNC and AC without suppression groups are compared, there was a statistically significant difference in clinical pregnancy rate in favor of tNC, whereas it failed to reach statistical significance for live birth. When tNC and AC with suppression groups are compared, there was a statistically significant difference in live birth rate favoring the latter. Similar pregnancy outcome was noted among mNC versus AC with or without suppression groups. Similarly, no difference in clinical pregnancy and live birth was noted when ACs with or without suppression groups are compared.

Conclusions

There is no consistent superiority of any endometrial preparation for FER. However, mNC has several advantages (being patient-friendly; yielding at least equivalent or better pregnancy rates when compared with tNC and AC with or without suppression; may not require LPS). Mild OS with Gn or AI may be promising.
  相似文献   
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