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71.
We describe here a computational morphology-based approach to the investigation of possible causes of chromatin alterations in sperm. A comprehensive set of state-of-the-art and geometric measures are computationally extracted from toluidine blue stained images and analyzed to infer the possible processes leading to normal and abnormal chromatin formation while seeking a possible taxonomy of chromatin alterations and their influence on sperm head morphology. Using this methodology, we have identified higher chromatin fragility at some specific points of the sperm head. Despite the lack of correlation between morphologies of sperm head and chromatin structure, four main morphological types of chromatin alterations in bull spermatozoa have been identified and their possible causes discussed. 相似文献
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Epigenetics refers to heritable changes in gene expression that are independent of alterations in DNA sequence. It is now accepted that disruption of epigenetic mechanisms plays a key role in the pathogenesis of cancer: culminating in altered gene function and malignant cellular transformation. DNA methylation and histone modifications are the most widely studied changes but non-coding RNAs such as miRNAs are also considered part of the epigenetic machinery. The insulin-like growth factor (IGF) axis is composed of two ligands, IGF-I and –II, their receptors and six high affinity IGF binding proteins (IGFBPs). The IGF axis plays a key role in cancer development and progression. As IGFBP genes have consistently been identified among the most common to be aberrantly altered in tumours, this review will focus on epigenetic regulation of IGFBP-3 in cancer for which the majority of evidence has been obtained. 相似文献
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Economic Botany - The usage and cultural importance of wild and weedy edible leaves of wild relatives of sesame, Ceratotheca and Sesamum in Africa, is reported from herbarium records, published... 相似文献
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Gregory J. Anderson Neil A. Harriman Neil A. Harriman Melissa B. Riley Lawrence Kaplan Lytton J. Musselman Conrad Richter Nigist Asfaw Sebsebe Demissew Dorothea Bedigian Bradley C. Bennett Susan Carty Mary Eubanks Neil A. Harriman Daniel F. Austin Anupam Gaonkar Julia Morton Donald J. Pinkava Daniel F. Austin Monique Reed Michael J. Balick 《Economic botany》1996,50(3):340-352
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