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In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.   相似文献   
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BackgroundThe timely evaluation of ocular conditions in the emergency department (ED) can be difficult due to a general lack of specialized equipment, trained personnel, and the time-sensitive nature of emergent ocular conditions. Recently, the use of ocular point-of-care ultrasound (POCUS) has been shown to be particularly useful in the ED. POCUS can be used to promptly diagnose various ocular pathologies, which include ocular trauma, vitreous hemorrhage, central retinal artery occlusion, and retinal detachment.ObjectivesThis narrative review seeks to inform the reader of current literature regarding the use of POCUS for the assessment of various ocular emergencies in the ED. The goal of this review is to provide the emergency physician with succinct and up-to-date information and instruction regarding the current uses of POCUS for patients presenting with particular ocular emergencies. Ocular pathologies that are common (ocular trauma) or for which ultrasound is particularly useful (such as retinal detachment) are discussed. Other ocular pathologies are also briefly discussed, such as central retinal artery occlusion, which is a promising new application for ultrasound evaluation.DiscussionThere have been many studies that provide evidence for the utility of POCUS in the evaluation of trauma and other ocular pathologies, including vitreous hemorrhage, retinal detachment, and central retinal artery occlusion.ConclusionsOcular POCUS is a useful modality in the evaluation of acute ocular complaints in the ED. Emergency physicians should be aware of these findings and feel confident in the utility of ocular POCUS in the ED.  相似文献   
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We describe the case of a 24 year old male with severe fistulating Crohn's disease who failed mutliple modalities of medical and surgical therapy. We present objective and subjective evidence of disease remission after induction and maintenance treatment with leukocyte apheresis. This is the first described case of successful maintenance treatment of severe Crohn's disease with leukocyte apheresis in the United Kingdom. J. Clin. Apheresis 29:181–182, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Lu  YQ; Nichols  ME; Bigbee  WL; Nagel  RL; Blumenfeld  OO 《Blood》1987,69(2):618-624
We have explored the polymorphism of the glycophorin system in the human erythrocyte membrane using the immunoblotting techniques and examining 52 individuals selected without prior bias as to their serologic state and ten documented serologic variants of M, N, S, s blood group system. Polyclonal antisera to alpha glycophorin and to alpha glycophorin CNBr carboxyl terminal fragment C (residues 82-131) and M and N specific monoclonal antibodies (MoAbs) were used. The first two reagents detect specific regions of the alpha glycophorin molecule and all electrophoretically resolved species of glycophorins immunologically related to alpha and delta glycophorins (delta glycophorin, [alpha-delta] hybrids and other glycophorins with an alteration in the carboxyl terminal segment); the M and N MoAbs identified the glycophorin species containing or lacking the M or N determinant in the amino terminal octapeptide structures. We find that immunoblotting confirmed in all cases the serologically determined phenotype; we also find that polymorphic forms of the glycophorin system are relatively infrequent; immunoblotting, independent from serologic testing, was capable of detecting five mutants, two most likely S-s-U-phenotypes; a new glycophorin species was detected in normal red cells with both antiglycophorin and antipeptide C sera, which is not evident with MoAbs; immunoblots of known glycophorin variants (En(a-), U-, Mg, Mi I, II, III, V, and Sta) confirmed but also extended our knowledge of the abnormal glycophorins involved; and the He+ and Wrb(-) cells showed normal patterns.  相似文献   
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