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Recently, many papers have shown that tumor vascularization can be explained by angiogenesis, recruitment, cooption, vasculogenic mimicry and by mosaic vessels. In particular, vasculogenic mimicry seems to be different from mosaic blood vessels, where tumor cells form a part of the surface of the vessel while the remaining part is covered by endothelium. In this case, tumor cells in apparent contact with the lumen do not show an endothelial phenotype. More recently, vasculogenic mimicry was proposed to occur in patients with multiple myeloma due to bone marrow macrophages. Herein, all these data are, for the first time, discussed critically in comparison to cancer stem cells-which show high trans-differentiative capacity-and bone-marrow derived stem cells. In fact, the presence of alternative vasculogenic patterns might be due to the presence of stem cell population (cancer stem cells or bone-marrow stem cells). In this connection, the literature is discussed extensively and possible models are proposed. Pharmacological perspectives will also discuss. 相似文献
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Vigorous compression is required to minimize radiation dose and maximize image quality for screen-film mammography. Of 356 women who adequately completed a questionnaire following mammography, 171 (48%) reported mammography to be comfortable, 135 (38%) uncomfortable but tolerable, 39 (11%) very uncomfortable, and only 11 (3%) found the examination to be intolerable. Only 14 women (4%) indicated that they would not return for mammography at our facility in the future. Because of this high level of acceptance of compression by women, technologists and radiologists should not hesitate to use vigorous compression to optimize image quality and decrease radiation dose to the patient. 相似文献
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DAVENPORT A; DAVISON AM; WILL EJ; NEWTON KE; TOOTHILL C 《QJM : monthly journal of the Association of Physicians》1991,79(2):407-423
We monitored urinary aluminium excretion in 60 renal allograftrecipients for the first 6 months following transplantation.Plasma and urinary aluminium values steadily decreased duringthe study period. Patients who suffered two or more bacterialinfections during this period excreted more urinary aluminiumthan those with only one or no infections. Twenty patients experienced a two-fold or greater sudden unexpectedincrease in urinary aluminium excretion; 14 of these patients(60 per cent) had evidence of infection (10 bacterial and fourviral), at this time. Both urinary aluminium and fractionalaluminium excretion were greater in the 10 patients with bacterialinfection than in the other 10 patients. Thus, patients who suffered bacterial infections had higherbase-line urinary aluminium excretion, suggesting a higher bodyburden of aluminium. In addition, bacterial sepsis was associatedwith aluminium release from tissue stores with an associatedincrease in urinary aluminium excretion. This implies that patientswith an increased body burden of aluminium are more prone tobacterial sepsis, and that aluminium excretion is increasedduring sepsis. 相似文献
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