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31.
Markowitz  RI 《Radiology》1988,167(3):717-719
The anterior junction line is a normal anatomic landmark on chest radiographs of healthy adults and older children caused by the visceral and parietal pleurae of the two lungs meeting anteriorly at the midline. It is not seen on chest radiographs of healthy infants. When this sign is identified on the supine frontal view of a neonate, it signifies bilateral pneumothorax. In this situation the line is formed by the meeting of the medial parietal pleurae on each side as they herniate anteriorly in front of the thymus and heart. The sign is best seen when the patient is rotated slightly to the left. It is not seen when there is unilateral pneumothorax or a concomitant pneumomediastinum. Although the anterior junction line is not a highly sensitive indicator of bilateral pneumothorax, it is highly specific and its recognition can promote faster diagnosis.  相似文献   
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As an alternative to performing interventional radiology on inpatients under the care of internists and surgeons, the authors have established a cardiovascular radiology admitting service for well-screened, elective patients. The patients are admitted under the care of a cardiovascular radiology fellow and a staff physician. From April 1982 to December 1983, 133 patients were admitted to the service. Patients are cared for in a surgical ward or in an intermediate unit, as determined by the clinical situation. Advantages of this approach include a broader patient referral base, improved rapport with clinical colleagues and patients, improved follow-up data, and rapid evaluation and treatment, resulting in short hospital stays. The major disadvantages involve the commitment of time and staff necessary to provide quality care. The concept of the interventional radiologist in the role of admitting physician has important implications in terms of negotiations for additional financial compensation, commensurate with the skill and time required for performing these procedures and caring for the patient.  相似文献   
35.
Liver tumors in women on contraceptive steroids.   总被引:2,自引:0,他引:2  
The possible association between oral contraceptives and benign liver tumors has recently been reported. To date the majority of cases have been diagnosed as benign hepatomas (liver cell adenomas). We have had the opportunity to study 13 such cases. Eight have been examples of focal nodular hyperplasia of the liver; however, in addition, there were examples of hepatocellular carcinoma, liver cell adenoma, and possible liver cell hamartoma; all were in women on "the pill." Gynecologists are alerted to the fact that many of the patients present with symptoms of acute abdomen, syncope or shock, and intrahepatic or intraperitoneal bleeding. Prompt diagnosis and treatment may be lifesaving.  相似文献   
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Compelling evidence now exists supporting the involvement of chemokines in the pathogenesis of autoimmune diseases. Examples of chemokines and chemokine receptors being involved in mediating autoimmune disease exist for rheumatoid arthritis, multiple sclerosis, allograft rejection, systemic lupus erythematosus, psoriasis, atopic dermatitis, lichen planus, and graft-versus-host-disease. Expression of chemokines by endothelial cells appears to be an important step in the development of these diseases. Since chemokines are small molecular weight molecules that act through G-protein coupled receptors, they make attractive drug targets. Several antagonists of chemokine - chemokine receptor interactions have been used to successfully alleviate some or all of the symptoms associated with many of these diseases in animal models. Further investigation of the involvement of chemokines in the pathogenesis or progression of autoimmune diseases may lead to practical clinical advances in diagnosis, prognosis, and therapy of such diseases.  相似文献   
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OBJECTIVE: To measure the strength of the association between the factor V Leiden mutation and venous thromboembolism in gynecologic oncology patients. METHODS: We conducted a case-control study of gynecologic cancer patients in a referral center who were group matched for demographics, tumor type, and treatment. The prevalence of the factor V Leiden mutation was determined in both cases and controls, and an odds ratio was calculated. The factor V Leiden mutation was detected using polymerase chain reaction amplification and nucleic acid restriction digest of deoxyribonucleic acid extracted from leukocytes. RESULTS: Seventy-five patients were enrolled in the study. Seventy-four samples were available for analysis. There were no differences between the cases and controls with respect to age, race, body mass index, smoking, cancer type, high stage (III or IV) of cancer, or treatment modality. The odds ratio for having the factor V Leiden mutation in patients with venous thromboembolism was 0.3 (95% confidence interval 0.1, 1.7). CONCLUSION: This study suggests that the factor V Leiden mutation is not associated with an increased risk of venous thromboembolism in gynecologic oncology patients. This contrasts with other studies showing a strong association between the factor V Leiden mutation and venous thromboembolism in cases of previously unexplained venous thromboembolism, and venous thromboembolism associated with other hypercoagulable states, such as pregnancy and oral contraceptive use. The risk of venous thromboembolism due to cancer outweighs the contribution of the factor V Leiden mutation.  相似文献   
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OBJECTIVES: To determine the levels of residual HIV DNA and RNA in blood and gut reservoirs in aviremic patients, assess correlations among compartmental measurements of HIV burden, and evaluate association with clinical parameters. DESIGN: Cross-sectional analysis of baseline data only, on 40 patients enrolled in phase II study evaluating efficacy of autologous gene-modified CD4+ and CD8+ T cells. All patients were on stable antiretroviral regimen with undetectable plasma HIV RNA (< 50 copies/ml). METHODS: Measurements repeatedly performed over 8-12 weeks pre-intervention: blood HIV DNA, analysis of rectal mucosa-associated lymphoid tissue for both HIV RNA and HIV DNA, and quantitative co-culture of HIV from CD8-depleted peripheral blood mononuclear cells (PBMC). RESULTS: Quantifiable levels of HIV detected in compartments despite undetectable levels of plasma HIV RNA: HIV co-culture of PBMC (88%), blood HIV DNA (95%), rectal biopsy HIV DNA (95%), rectal biopsy HIV RNA (65%). A significant correlation existed among various measures of HIV burden (HIV co-culture, blood HIV DNA, rectal biopsy HIV RNA and DNA) but not between assays and clinical parameters [duration of highly active antiretroviral therapy (HAART), type of HAART]. All assays had comparable or less variability than in plasma viral load assays; HIV co-culture had the highest coefficient of variability whereas the blood HIV DNA assay had the lowest and was considered the most reliable assay. CONCLUSIONS: The data support safety, feasibility and high compliance of quantifying reservoirs of residual HIV in treated subjects with undetectable plasma HIV RNA. Lack of correlation between levels of HIV in residual reservoirs and duration of HAART suggests treatment-mediated viral suppression alone does not lead to reproducible decay in HIV reservoirs.  相似文献   
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Different leukemias express on their plasma membranes particular subsets of the 247 defined cluster of differentiation (CD) antigens, which may resemble those of precursor cells along the lineages of differentiation to mature myeloid and lymphoid leukocytes. The extent of use of CD antigen expression (immunophenotyping) for identification of leukemias has been constrained by the technique used, flow cytometry, which commonly specifies only three CD antigens in any one assay. Currently, leukemias and lymphomas are diagnosed using a combination of morphology, immunophenotype, cytochemistry, and karyotype. We have developed a rapid, simple procedure, which enables concurrent determination of 50 or more CD antigens on leukocytes or leukemia cells in a single analysis using a microarray of antibodies. A suspension of cells is applied to the array, and cells only bind to antibody dots for which they express the corresponding CD antigen. For patients with significantly raised leukocyte counts, the resulting dot pattern then represents the immunophenotype of those cells. For patients at earlier stages of disease, the diagnosis depends on recognition of dot patterns distinct from the background of normal leukocytes. Distinctive and reproducible dot patterns have been obtained for normal peripheral blood leukocytes, chronic lymphocytic leukemia (CLL), hairy cell leukemia, mantle cell lymphoma, acute myeloid leukemia, and T-cell acute lymphoblastic leukemia. The consensus pattern for CD antigen expression found on CLL cells taken from 20 patients in descending order of cells bound was CD44, HLA-DR, CD37, CD19, CD20, CD5, CD52, CD45RA, CD22, CD24, CD45, CD23, CD21, CD71, CD11c, and CD9. The antigens that provided the best discrimination between CLL and normal peripheral blood leukocytes were CD19, CD20, CD21, CD22, CD23, CD24, CD25, and CD37. Results obtained for the expression of 48 CD antigens from the microarray compared well with flow cytometry. The microarray enables extensive immunophenotyping, and the intact cells captured on antibody dots can be further characterized using soluble, fluorescently labeled antibodies.  相似文献   
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