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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Aims : The aim of this study was to report four cases of pleomorphic adenoma which were characterized by intra-vascular tumour. Methods and results : The patients ranged in age from 13–43 years, one was male while three were female. The tumours were situated in the parotid gland, submandibular gland and palate (two cases). The intra-vascular tumour consisted of single, clustered and solid cords of cells within multiple muscular walled blood vessels and capillaries both in the capsule and in the tumour. Immunoperoxidase staining confirmed that the intra-vascular cells were phenotypically identical to those of the tumour. The possibility that the intra-vascular tumour represents artefactual 'spillage' has been considered, however there is some histological evidence suggesting that this phenomenon represents true vascular invasion. Conclusions : The biological significance of intra-vascular tumour in pleomorphic adenomas is unknown. Thus far there has been no correlation with either recurrence or metastases. 相似文献
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Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
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Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
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The desired properties required for successful embalming of cadavers for gross anatomy teaching include: (1) good long-term structural preservation of organs and tissues with minimal shrinkage or distortion; (2) prevention of over-hardening, while maintaining flexibility and suppleness of internal organs; (3) prevention of desiccation; (4) prevention of fungal or bacterial growth and spread within a specific cadaver and to other cadavers in the dissection room; (5) reduction of potential biohazards (spread of infection to dissection personnel and students); (6) reduction of environmental chemical hazards (especially from formaldehyde and phenol) in order to comply with increasingly severe health and safety regulations and a new awareness of possible dangers of these chemicals in the workplace; and (7) retention of colour of tissues and organs while minimising oxidation effects that result in 'browning'. 相似文献