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61.
D. Han J. H. Sohn Y. J. Cho Y. C. Jeon H. J. Kim K. N. Park S. J. Chang 《Journal of Korean medical science》1997,12(5):465-468
A flat depressed early colon cancer (FDEC) is characterized by non-polypoid growth pattern, no association of adenomatous tissues and a tendency of even small lesions toward submucosal invasion and lymph node metastasis. It supports de novo carcinogenesis of colorectal cancer, although most colorectal cancers arise in pre-existing adenoma (adenoma-carcinoma sequence). There have been few reports of small depressed cancers because of the difficulty in colonoscopic detection and the rapid development to ulcerating advanced cancers. We report a case of flat depressed early colon cancer confined to mucosa detected by indigo carmine contrast colonoscopy. 相似文献
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Johanna L. Schmidt MPH MGC CGC Amy Pizzino MS CGC Jessica Nicholl MS CGC Allison Foley MMSc CGC Yue Wang PhD FACMG Jill A. Rosenfeld MS CGC Lindsey Mighion MS CGC Lora Bean PhD Cristina da Silva MS Megan T. Cho MS CGC Rebecca Truty PhD John Garcia PhD Virginia Speare PhD Kirsten Blanco BS Zoe Powis MS CGC Grace M. Hobson PhD Susan Kirwin BS Bryan Krock PhD FACMG Hane Lee PhD Joshua L. Deignan PhD Maggie A. Westemeyer MS CGC Ryan L. Subaran PhD Isabelle Thiffault PhD FABMGG Ellen A. Tsai PhD Terry Fang PhD Guy Helman BS Adeline Vanderver MD 《American journal of medical genetics. Part A》2020,182(8):1906-1912
Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies. We assessed the relative frequency of all 30 leukodystrophies (associated with 55 genes) in more than 49,000 exomes. We identified a relatively high frequency of disorders previously thought of as very rare, including Aicardi Goutières Syndrome, TUBB4A‐related leukodystrophy, Peroxisomal biogenesis disorders, POLR3‐related Leukodystrophy, Vanishing White Matter, and Pelizaeus‐Merzbacher Disease. Despite the relative frequency of these conditions, carrier‐screening laboratories regularly test only 20 of the 55 leukodystrophy‐related genes, and do not test at all, or test only one or a few, genes for some of the higher frequency disorders. Relative frequency of leukodystrophies previously considered very rare suggests these disorders may benefit from expanded carrier screening. 相似文献
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Yongchol Shin Atsushi Kitayama Tetsuya Koide Daniel A Peiffer Makoto Mochii Arnold Liao Naoto Ueno Ken W Y Cho 《Developmental dynamics》2005,232(2):432-444
To isolate novel genes regulating neural induction, we used a DNA microarray approach. As neural induction is thought to occur by means of the inhibition of bone morphogenetic protein (BMP) signaling, BMP signaling was inhibited in ectodermal cells by overexpression of a dominant-negative receptor. RNAs were isolated from control animal cap explants and from dominant-negative BMP receptor expressing animal caps and subjected to a microarray experiment using newly generated high-density Xenopus DNA microarray chips representing over 17,000 unigenes. We have identified 77 genes that are induced in animal caps after inhibition of BMP signaling, and all of these genes were subjected to whole-mount in situ hybridization analysis. Thirty-two genes showed specific expression in neural tissues. Of the 32, 14 genes have never been linked to neural induction. Two genes that are highly induced by BMP inhibition are inhibitors of Wnt signaling, suggesting that a key step in neural induction is to produce Wnt antagonists to promote anterior neural plate development. Our current analysis also proves that a microarray approach is useful in identifying novel candidate factors involved in neural induction and patterning. 相似文献
66.
This report describes an 11 month old female baby with features of pentasomy X. A molecular and cytogenetic evaluation revealed that her karyotype was 49,XXXXX and her extra X chromosomes were of maternal origin. She has muscular hypotonia, mental retardation, a cleft palate, mild hydrocephalus as a result of dilatation of both lateral ventricles, hyperextensible elbow joints, proximal radioulnar synostosis, clinodactyly of the fifth finger, valgus of the feet, and small hands and feet. In addition, she has a persistent pupillary membrane and congenital chorioretinal atrophy. The pathogenesis of pentasomy X is not clear at present, but it is thought to be caused by successive maternal non-dysjunctions. 相似文献
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T S Hwang J S Suh Y I Kim S H Park B Y Cho C S Koh 《Journal of Korean medical science》1990,5(1):33-37
To determine the content of thyroglobulin in oxyphilic cells of the thyroid, which have been considered as non-thyroglobulin producing cells, the degree of stainability of the various oxyphilic cells for thyroglobulin was compared with that of non-oxyphilic follicular cells in either same or different lesion. A total of 13 oxyphilic lesions, including three follicular adenomas containing oxyphilic cell nodules, four pure oxyphilic cell adenomas, and six Hashimoto's thyroiditis were compared with 16 of non-oxyphilic lesions such as, seven follicular adenomas, four chronic lymphocytic thyroiditis, and five Graves' disease. Many oxyphilic cells stained positively for thyroglobulin regardless of their morphologic variation, but less intensely than the usual follicular cells in follicular adenomas, chronic lymphocytic thyroiditis, and Graves' disease. The stainability of oxyphilic cells for thyroglogulin did not show any significant correlation with morphologic features, whereas in follicular adenomas, the non-oxyphilic follicular cells forming microfollicles stained less strongly for thyroglobulin than the same cells lining large mature follicles in a reproducible way. With above findings, we concluded that oxyphilic cells maintain the functional activity in terms of thyroglobulin synthesis, although the content of the thyroglobulin is less than that of non-oxyphilic colloid forming follicular cells. 相似文献
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