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1.
Nager acrofacial dysostosis is a variant of mandibulofacial dysostosis with severe micrognathia, malar hypoplasia, and radial limb defects. Most cases are sporadic, but autosomal recessive inheritance has been suggested. A family is reported in which two sibs are affected by this syndrome, presenting further evidence for autosomal recessive inheritance. The recognition of this syndrome as a distinct entity has important implications. After the birth of a child with orofacial malformations suggestive of mandibulofacial dysostosis, an exact diagnosis is essential before genetic counselling can be offered.  相似文献   
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The mission of the Society for Craniofacial Genetics and Developmental Biology (SCGDB) is to promote education, research, and communication about normal and abnormal development of the tissues and organs of the head. The SCGDB welcomes as members undergraduate students, graduate students, postdoctoral researchers, medical and dental practitioners, scientists, and academicians who possess an interest in craniofacial biology. Each year our members come together to share their novel findings, build upon, and challenge current knowledge of craniofacial biology.  相似文献   
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Breast cancers that are found and confirmed because they are causing symptoms tend to be larger and are more likely to have already spread to the lymph nodes and beyond. Thus, early detection and confirmation are of paramount importance. The normalized axial–shear strain area (NASSA) feature from the axial-shear strain elastogram (ASSE) has been shown to be a feature that can identify the boundary-bonding conditions that are indicative of the presence of cancer. Recently, we investigated and reported on the potential of the NASSA feature for breast lesion classification into fibroadenomas and cancers. In this article, we investigate the size distribution of the lesions that were part of the previous study and analyze classification performance specifically on small lesions (<10 mm diameter). A total of 33 biopsy-proven malignant tumors and 30 fibroadenomas were part of the study that involved three observers blinded to the Breast Imaging Reporting and Data System (BIRADS) ultrasound scores. The observers outlined the lesions on the sonograms and the lesion size (maximum circle-equivalent diameter in millimeters) was computed from this outline. The ASSE was automatically segmented and color-overlaid on the sonogram, and the NASSA feature from ASSE was computed semi-automatically. Receiver operating characteristic curves were then generated for the subset of cases involving small lesions. Box plots were produced for the two different lesion size groups, small and large, from a logistic regression classifier that was built previously. The results of our study show that approximately 38% and 22% of the fibroadenomas and cancers, respectively, were small. Furthermore, it was found that the NASSA feature resulted in a perfect classification of the small lesions, both in the training data and in the cross-validation. For lesions <10 mm the difference in fibroadenoma and cancer mean scores was 0.73 ± 0.13 (p < 0.001), whereas lesions >10 mm had a difference of 0.52 ± 0.24 (p < 0.001). The results also showed that the small lesions actually had better classification than the larger lesions (>10 mm). These results suggest that the ASSE feature can work equally well, even on small lesions, to improve the standard ultrasound BIRADS–based breast lesion classification of fibroadenoma and malignant tumors.  相似文献   
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Porat  Daniel  Margolin  Nadia  Lavon  Ophir  Dahan  Arik 《Obesity surgery》2022,32(10):3481-3486
Obesity Surgery - Bariatric surgery modifies the anatomy and physiology of the gastrointestinal tract. Carbamazepine (CBZ) is an anticonvulsant with multiple neuropsychiatric indications. Given CBZ...  相似文献   
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Contrast agents in diagnostic ultrasound   总被引:11,自引:0,他引:11  
We review the field of contrast agents in diagnostic ultrasound. The progress in the development of various classes of contrast agents such as free and encapsulated gas bubbles, colloidal suspensions, emulsions, and aqueous solutions is described. The mechanisms for production of backscatter contrast, as well as attenuation contrast and speed of sound contrast are explained. Finally, the potential advantages and disadvantages of various classes of contrast agents are compared.  相似文献   
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Lateral resolution in elastography   总被引:2,自引:0,他引:2  
The factors that control the lateral resolution in elastography were investigated using a simulation study. The lateral resolution was estimated from the simulated axial strain elastograms as the smallest measurable distance between two equally stiff lesions embedded in a homogeneously softer background. The lesions were symmetrically positioned lateral to the center of the target, at the focus of the transducer. Ultrasound (US) systems with different transducer frequencies, bandwidths and f-numbers were simulated. The effects of the ultrasonic parameters, the lateral spacing between adjacent echo signals, the cross-correlation window length, the lesion/background elastic contrast and the lateral motion of scatterers on the estimated lateral resolution were investigated. The results show that the lateral resolution in elastography is proportional to the beam width of the US system used to acquire the data, and is on the same order as the sonographic lateral resolution.  相似文献   
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A randomized controlled trial of treatment with thymic humoral factor (THF) in 20 children with severe complicated acute measles infection, resulted in objective benefit as evidenced by improvement in the ESR and a fall in C-reactive protein, fewer complications and a reduced incidence of secondary herpes infection. An increased ratio of helper to suppressor T cells (OKT4/OKT8 ratio) and a greater lymphocyte transformation response to phytohaemagglutin was seen in those children receiving THF. We conclude that THF treatment helps to prevent the development of complications particularly secondary viral infections possibly by enhancing cell-mediated immune responses.  相似文献   
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