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991.
Myelosarcoma (chloroma) is a rare primary condition in patients with either a myelodysplastic syndrome, or an acute or chronic leukemia. It is an extramedullary neoplasm which does not commonly present with changes in peripheral blood or bone marrow. The rarity and histomorphological similarity to malignant non-Hodgkin lymphoma renders the diagnosis notoriously difficult. Due to its coincidental or secondary manifestation followed by myelogenous leukemia, this tumor needs to be seen as a primary systemic disease. We present a 40 year old man with myelosarcoma of the jejunum and discuss this entity and its therapeutic options. 相似文献
992.
This article describes the imaging tools for efficient diagnostic management of head trauma victims. The basic mechanisms of brain injuries are explained and the imaging features are described. Computed tomography remains the most important method for the initial screening and follow-up investigation. Though magnetic resonance imaging has higher sensitivity to most traumatic lesions, it does not play an important role in the acute phase of head trauma patients. In the first part of this paper clinical classifications, imaging modalities, extra-axial injuries, and contusions are described. In the second part of this paper intra-axial and secondary injuries are discussed. 相似文献
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Glomus tumors of the head and neck are rare tumors of adulthood which arise from paraganglia or glomus cells within the carotid glomus, vagus nerve, middle ear or jugular foramen. The diagnosis of these mostly benign lesions is predominantly done with CT and MRI. DSA can provide important additional information. Besides surgical resection, one therapy option is radiological intervention with tumor embolisation. Because of the typical radiological imaging and the “salt and pepper appearance” in MRI, glomus tumors can be differentiated from other lesions in the head and neck. This review gives a survey of the classification, diagnosis and therapy of paragangliomas with images to demonstrate characteristic features. 相似文献
996.
The molecular basis of type I or III Protein S deficiency has been investigated in three kindred also showing independent inheritance of factor V (FV) Leiden. A T to C transition in codon 570 (Met-->Thr) was identified in the propositi and shown to segregate with protein S deficiency in all but one of the affected members of two kindred. This individual was heterozygous for a second transition (C to T) causing substitution of serine 624 by leucine. A second member of the same family, with markedly reduced free protein S levels when compared with affected relatives, was heterozygous for both mutations. Haplotype analysis of individuals with the mutated ATG570ACG allele in the two kindred suggested they may have been related by a common ancestor. A G to A transition resulting in substitution of cysteine 145 by tyrosine was detected in the third kindred. All mutations are believed to interfere with protein S binding to C4b-binding protein resulting in reduced free protein S levels. Of the five individuals studied who had experienced thrombotic events, three had combined protein S deficiency and FV Leiden reemphasising the importance of FV Leiden as an additional risk factor for thrombosis in protein S deficiency. 相似文献
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Previous studies from our laboratories have shown that transgenic mice expressing high levels of beta S globin are well-protected from Plasmodium chabaudi adami and partially protected against P berghei (Shear et al, Blood 81:222, 1993). We have now infected transgenic mice expressing low (39%), intermediate (57%), and high (75%) levels of beta S with the virulent strain of P yoelii (17XL) that appears to cause cerebral malaria. We find that the level of protection in these three groups of mice correlates positively with the level of beta S chain expression in the mice. Seven of nine mice expressing the high level of beta S recovered from infection, as did 7 of 9 mice expressing the intermediate level of beta S. Control mice and mice expressing the lower level of beta S all succumbed to infection. In mice expressing high and intermediate levels of beta S, parasites were found almost exclusively in reticulocytes during recovery, suggesting that mature red blood cells expressing beta S are more resistant than reticulocytes. These studies confirm epidemiologic data and offer insight into the mechanism of protection of sickle trait individuals against falciparum malaria. 相似文献
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Lactating adenoma: US features and literature review 总被引:2,自引:0,他引:2