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1.
The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease. 相似文献
2.
Developmental regulation of annexin II (Lipocortin 2) in human brain and expression in high grade glioma. 总被引:7,自引:0,他引:7
In experiments to identify molecules that might be important in the pathogenesis of glioblastoma multiforme, the most common malignant brain tumor, we found that annexin II (Lipocortin 2, p36), a likely second messenger in several different mitogenic pathways, was highly expressed in tumor tissue of glioblastoma multiforme (9 of 9) and highly anaplastic astrocytoma (2 of 6), but not in astrocytomas of lower pathological grade (0 of 6). We also detected high levels of annexin II expression in fetal brain during the period when radial glia proliferate, although annexin II expression was not detected in normal adult brain. These data demonstrate that annexin II expression is developmentally regulated in the human central nervous system and suggest that the early progenitor radial glia share important characteristics with highly malignant glial tumors. 相似文献
3.
Marcos Daccarett MD Gustavo Espinosa MD FACR Fred Rahimi DPM Christopher M. Eckerman DPM Shelley Wayne-Bruton DPM Mark Couture DPM Jason Rosenblum DPM 《The Journal of foot and ankle surgery》2002,41(6):372-378
Dactylolysis spontanea is an idiopathic condition affecting the fifth toe, and sometimes other toes, that is frequently bilateral, with lesions in different stages. Between 1977 and 1999, a total 6000 radiographic studies of the feet were reviewed in a mainly African American population in Chicago, Illinois. After an initial screening based on the Cole criteria, 581 patients were selected and re-examined, and amplification techniques were performed. After reviewing the complementary exams, 102 patients were diagnosed with dactylolysis spontanea or ainhum. Soft-tissue constriction was the most frequently presented radiological sign on the initial screening. Kurtosis at the digit plantar fold and marked rotation of the fifth toe were normal findings in asymptomatic patients. Demographics, comorbidities, and radiological findings were analyzed in the selected population. Associated diseases occurring in these patients appeared to have no specific etiologic correlation with ainhum. African Americans and the dark-skinned population are affected exclusively by this condition, presumably due to the fibrogenic tendency of these individuals. Early diagnosis and accurate staging of ainhum are facilitated by radiological examination of the feet. The findings suggest that this condition is underdiagnosed and overlooked because its low prevalence and variable clinical presentations that might mimic more common etiologies, including localized trauma. 相似文献
4.
C McKenzie BAppSc P Megaw BAppSc I Morgan PhD MK Boelen PhD 《Clinical & experimental ophthalmology》1997,25(4):79-81
Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth. 相似文献
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A new in vitro model of normal human brain has been developed in which fetal human brain cells form three-dimensional aggregates that can be maintained for up to 60 days in culture. Cells appear fully differentiated at the time of initiation in culture; the predominant cells identified were astrocytes, neurons, and oligodendrocytes with myelin, with occasional ependymal cells and macrophages. The specific arrangement and numbers of neural cells within aggregates differed among brain specimens. Cell kinetics studies detected DNA synthesis throughout the culture interval. Aggregates cocultured with a human malignant glioma cell line (U251-MG) were progressively invaded by tumor cells. In aggregates infected with human cytomegalovirus (CMV), intracellular viral replication and morphologic changes characteristic of human brain infection with this pathogen were seen. This model of brain aggregates should prove valuable for multidisciplinary studies in human neurobiology, particularly in the fields of developmental neurobiology, neuro-oncogenesis, tumor cell invasion, and species-specific viral infection of the central nervous system. 相似文献
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Use of CT and MR imaging to distinguish intracranial lesions and to define the need for biopsy in AIDS patients 总被引:2,自引:0,他引:2
To explore the potential usefulness of imaging studies in the diagnosis of focal central nervous system (CNS) lesions associated with acquired immunodeficiency syndrome (AIDS), the authors retrospectively examined the radiographic studies of 149 AIDS patients who presented with signs and symptoms of the three most common focal CNS lesions. Of these patients, 74 (50%) had Toxoplasma abscesses, 45 (30%) had primary CNS lymphoma, and 30 patients (20%) had progressive multifocal leukoencephalopathy (PML). Magnetic resonance (MR) imaging was more sensitive than computerized tomography (CT) in detecting lesions, especially in cases of PML. Whereas CT was unable to distinguish mass lesions caused by toxoplasmosis from those caused by lymphoma, 71% of the solitary lesions seen on MR images were lymphomas. These results indicate that empirical treatment for toxoplasmosis, the most common initial treatment for AIDS patients with neurological symptoms stemming from mass lesions, is not likely to be successful for patients with solitary lesions on MR images. Rather, early biopsy is advisable. If the presence of lymphoma is confirmed, the rapid initiation of treatment can allow prolonged high-quality survival. 相似文献
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