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51.
Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
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Papillomas and atypical papillomas in breast core needle biopsy specimens: risk of carcinoma in subsequent excision 总被引:8,自引:0,他引:8
Renshaw AA Derhagopian RP Tizol-Blanco DM Gould EW 《American journal of clinical pathology》2004,122(2):217-221
We sought to define the risk associated with papillomas and atypical papillomas in breast core needle biopsy specimens from a series of approximately 8,500 biopsies performed during 8 years. From a total of 62 papillary lesions (including papillomas and atypical papillomas), 40 (65%) had histologic follow-up. Overall, 15 (38%) of 40 patients had ductal carcinoma in situ (12 cases) or invasive carcinoma at excision (3 cases). Eight cases diagnosed as papilloma had benign follow-up. Slides were available for review in 38 cases and reclassified into benign papilloma with florid hyperplasia and no or minimal atypia (18 cases), papilloma with separate foci of atypical ductal hyperplasia (7 cases), and severely atypical papillomas "suspicious" for papillary carcinoma (13 cases). Carcinoma was identified in 0 (0%), 2 (29%), and 12 (92%) cases, respectively. We conclude that while atypical papillary lesions and papillomas with associated atypical ductal hyperplasia in breast core needle biopsy specimens are associated with a risk of carcinoma, lesions diagnosed as papilloma or papilloma with no or minimal atypia are benign and do not need to be excised. 相似文献
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Nature's Swiss Army Knife: The Diverse Protective Roles of Anthocyanins in Leaves 总被引:11,自引:0,他引:11 下载免费PDF全文
Gould KS 《Journal of biomedicine & biotechnology》2004,2004(5):314-320
Anthocyanins, the pigments responsible forspectacular displays of vermilion in the leaves of deciduoustrees, have long been considered an extravagant waste of aplant's resources. Contemporary research, in contrast, has begunto show that the pigments can significantly influence the way aleaf responds to environmental stress. Anthocyanins have beenimplicated in tolerance to stressors as diverse as drought,UV-B, and heavy metals, as well as resistance toherbivores and pathogens. By absorbing high-energy quanta,anthocyanic cell vacuoles both protect chloroplasts from thephotoinhibitory and photooxidative effects of strong light, andprevent the catabolism of photolabile defence compounds.Anthocyanins also mitigate photooxidative injury in leaves byefficiently scavenging free radicals and reactive oxygen species.Far from being a useless by-product of the flavonoid pathway,these red pigments may in some instances be critical for plant survival. 相似文献
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Synaptophysin expression in neuroendocrine neoplasms as determined by immunocytochemistry. 总被引:6,自引:3,他引:6 下载免费PDF全文
V. E. Gould B. Wiedenmann I. Lee K. Schwechheimer B. Dockhorn-Dworniczak J. A. Radosevich R. Moll W. W. Franke 《The American journal of pathology》1987,126(2):243-257
Synaptophysin is an integral membrane glycoprotein originally isolated from presynaptic vesicles of bovine neurons. The authors have studied a wide spectrum of neuroendocrine (NE) neoplasms by immunofluorescence microscopy on cryostat sections of freshly frozen tissues using a monoclonal antibody to this protein (SY 38). Without exception, they found the identical--or a very similar--protein expressed in all neuroblastomas, ganglioneuroblastomas, ganglioneuromas, pheochromocytomas, and paragangliomas studied. In these "neural" type NE neoplasms, synaptophysin was coexpressed with neurofilament proteins. Synaptophysin was also demonstrated in NE neoplasms of "epithelial" type in which it was predominantly coexpressed with cytokeratins and desmoplakin. It was invariably found in all variants of islet cell neoplasms and in all medullary thyroid carcinomas. Synaptophysin was also demonstrated in several adenomas of the hypophysis and parathyroids, in the majority of carcinoids of the bronchopulmonary and gastrointestinal tracts, and in many, though not all, NE carcinomas of the same sites, and of the skin. Conversely, SY 38 did not immunostain any of a large number of benign and malignant non-NE epithelial neoplasms; nor was any immunostaining obtained in a group of mesenchymal tumors. It is remarkable that SY 38 did not immunostain a number of malignant melanomas, including several that were immunostained for neuron-specific enolase (NSE) and several neuropeptides. Parallel studies conducted on conventionally fixed, paraffin-embedded tissue sections immunostained by the use of the avidin-biotin complex technique yielded very similar results. The findings indicate that synaptophysin is expressed in the whole range of NE neoplasms without detectable relation to the expression of other NE markers such as NSE, serotonin, and neuropeptides. Nor could the expression of synaptophysin by these tumors be correlated with their epithelial and/or neural cytoskeletal characteristics, their clinical aggressiveness, or the presence or absence of endocrinologic abnormalities. While the consistent expression of synaptophysin by the "neural" type of NE neoplasms would seem predictable its presence in diverse benign and malignant NE tumors of "epithelial" type is remarkable. It is concluded that synaptophysin is a significant as well as novel NE marker, and the use of antibody SY 38 as a broad range marker for the study and diagnosis of NE neoplasms is proposed. 相似文献