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11.
Management of upper gastrointestinal bleeding because of erosion of vessels by esophageal cancer may be challenging. We present herein the angiographic images of a 49-year-old patient who was admitted with massive bleeding from a tumor-eroded inferior thyroid artery. Attempts to control the bleeding by means of flexible endoscopy and insertion of a Sengstaken–Blakemore tube had failed. The diagnosis was impressively demonstrated by multislice computed tomography with intravenous contrast in the arterial phase and multiplanar reconstructions (computed tomography angiography) and by digital subtraction angiography. The bleeding was successfully treated with superselective catheterization and coiling of the eroded vessel.  相似文献   
12.
Summary The monoclonal antibody Ki-67, which reacts with cells in the active part of the cell cycle, was used to evaluate immunocytochemically the growth fraction in 22 primary brain neoplasms. The percentage of labelled cells reflected the histological grade of malignancy of each neoplasms. High percentage of Ki-67-positive cells were observed in one choroid plexus carcinoma (60%), one primary melanoma of meninges (40%), three medulloblastomas (40%–50%), one anaplastic astrocytoma and six glioblastomas (10%–40%). One ependymoma had 7% positive cells. Rare positive cells (1%) were present in one pilocytic astrocytoma and one ganglioglioma. Except one negative case, the meningiomas (five cases) had values of positivity ranging from 1% to 6%. Two acoustic schwannomas were negative. These results suggest that immunocytochemical staining with the Ki-67 may be a useful method for measuring the growth fraction in brain neoplasms.Supported in part by Associazione Italiana Ricerca sul Cancro and Ministero Italiano della Pubblica Istruzione  相似文献   
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Our clinical experience with patients in Zimbabwe suggests that an arthropathy may be a feature of HIV disease. This takes two forms: the first is a reactive arthropathy usually affecting the large, lower limb joints with no other clinical features of a connective tissue disease. The second form is seen in association with features of complete or incomplete Reiter's syndrome with involvement of large and small peripheral joints (having an asymmetric distribution). Although this arthropathy may been seen in association with HIV positive asymptomatic disease and often is the reason for first presentation at hospital, the majority of our patients have clinical features of persistent generalized lymphadenopathy, plus or minus features of constitutional illness (such as fever, weight loss, and diarrhea). A small percentage of our patients have arthropathy in association with secondary systemic infection. Other locomotor conditions have been observed, although their numbers are too small to determine whether or not they truly are related to HIV disease. In Zimbabwe there is no association between the development of HIV-associated arthropathy and the presence of HLA-B27.  相似文献   
15.
Antigenic characterization of urothelial cells cultured from normal adult ureter was performed. These cells were cultured using a simplified isolation and culture technique and a commercially available serum-free medium. The cells growing in these cultures had epithelioid morphology and normal quantities of DNA. The antigen expression on these cultured normal urothelial cells was evaluated using a panel of monoclonal antibodies: 5G6.4, AN43, URO-5, anti-keratin and anti-blood group antibodies, and 425 (anti-epidermal growth factor receptor). Lower levels of anti-A and AN43 binding on cultured cells were observed than are seen on urothelial cells in sections of normal ureter, while the binding of anti-blood group H, 5G6.4, and URO-5 was unchanged. Binding of anti-epidermal growth factor receptor antibody 425 was improved if the cells were grown in medium lacking epidermal growth factor. These results confirm the urothelial origin of these cultured urothelial cells but indicate that some antigenic differences between cultured normal urothelial cells and urothelial cells in situ in the normal ureter exist.  相似文献   
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Several electrophoretic forms of human platelet arylsulfatase A (ASA), including variant type IIIa and normal type IVa, have been identified by nondenaturing polyacrylamide gel electrophoresis. An alcoholic population that we have analyzed is enriched in variant type IIIa compared with nonalcoholic psychiatric and normal controls. Individuals with the IIIa enzyme possess greatly reduced levels of ASA activity. To understand further the structural basis for the differences and their potential biological consequences, the nature of the ASA variant expressed by fibroblasts from different individuals was explored. The electrophoretic patterns of fibroblast ASA from the IIIa and IVa individuals differ in degree of phosphorylation. Furthermore, fibroblast ASA from IIIa individuals lacks an N -linked glycan found in ASA from IVa individuals. In addition, differences in peptide and/or posttranslational modification unrelated to the N -linked carbohydrate or phosphorylation exist between the fibroblast ASA from IIIa and IVa individuals. The finding that both fibroblasts and platelets exhibit related electrophoretic isoform patterns characteristic of the donor's ASA type allows for the use of fibroblasts to study the impact of ethanol on the metabolism of cells possessing different ASA types.  相似文献   
18.
Poverty, health services, and health status in rural America   总被引:5,自引:0,他引:5  
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status.  相似文献   
19.
The MR imaging features of a paraganglioma of the cauda equina with associated spinal cord cysts are presented. MR imaging showed the tumor to be isointense with the spinal cord on all pulse sequences and to enhance homogeneously. The intramedullary cysts had increased signal intensity on proton density- and T2-weighted images, and involved the cervical and thoracic regions.  相似文献   
20.
6-[(4-Quinolinyl)oxy]hexanoic acids and the corresponding esters were designed and synthesized as inhibitors of the production of arachidonic acid metabolites. The inhibitory activities were assayed in vitro by evaluation of serum leukotriene B4 and thromboxane B2 production. While all 6-[(4-quinolinyl)oxy]hexanoic acids and their esters proved to be inactive, the N-alkyl-4-quinolones, obtained as by-products in their synthesis, were found to be a new class of leukotriene biosynthesis inhibitors.  相似文献   
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