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B-cell lymphoproliferative disorders in children after bone marrow transplantation: radiologic manifestations 总被引:1,自引:0,他引:1
The radiographic findings in five pediatric patients in whom unregulated B-cell lymphoproliferative disorders developed following bone marrow transplantation are described. Four patients received T-cell-depleted bone marrow from mismatched donors and one received nondepleted marrow from a matched sibling donor. These disorders are similar to B-cell lymphoproliferative disorders that have been described in other immunosuppressed hosts. They are associated with Epstein-Barr virus and range from polyclonal proliferation without cytogenetic abnormalities to monoclonal lymphoma with clonal cytogenetic changes. Unlike other postallograft lymphoproliferative processes, B-cell lymphoproliferative disorders in these patients have not responded to antiviral therapy, immunologic therapy, or chemotherapy. The radiographic patterns of disease include diffuse or focal hepatic involvement; gallbladder wall thickening; and pulmonary, soft-tissue, and basal-ganglion masses. These radiologic findings are not specific and evaluation of tissue histology is required for diagnosis. 相似文献
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95.
AGI-1067: a multifunctional phenolic antioxidant,lipid modulator,anti-inflammatory and antiatherosclerotic agent 总被引:5,自引:0,他引:5
Sundell CL Somers PK Meng CQ Hoong LK Suen KL Hill RR Landers LK Chapman A Butteiger D Jones M Edwards D Daugherty A Wasserman MA Alexander RW Medford RM Saxena U 《The Journal of pharmacology and experimental therapeutics》2003,305(3):1116-1123
To explore the therapeutic efficacy and potential mechanisms of action of a new class of antiatherosclerotic drugs, AGI-1067 [mono[4-[[1-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1-methylethyl]thio]-2,6-bis(1,1-dimethylethyl)phenyl] ester] (butanedioc acid) was tested in several animal models of atherosclerosis. AGI-1067, a novel phenolic antioxidant, was well tolerated in a 1-year study in hypercholesterolemic cynomolgus monkeys. It lowered low-density lipoprotein cholesterol (LDLc) by 41 and 90% at oral doses of 50 and 150 mg/kg, respectively and increased high-density lipoprotein cholesterol (HDLc) by 107% at the higher dose. In contrast, another phenolic antioxidant, probucol, had a modest LDLc-lowering effect (15% at 250 mg/kg) while decreasing HDLc (37% at 150 mg/kg). Histopathology of the aortas and coronary arteries revealed no atherosclerosis in the AGI-1067 (150 mg/kg) group and minimal-to-moderate atherosclerosis in the vehicle and probucol (150 mg/kg) groups. AGI-1067 also inhibited atherosclerosis in LDL receptor-deficient (LDLr -/-) mice and apolipoprotein E-deficient (ApoE -/-) mice even in the absence of a lipid-lowering effect. In LDLr -/- mice, AGI-1067 reduced aortic atherosclerosis by 49%. In ApoE -/- mice, AGI-1067 reduced atherosclerosis by 25, 41, and 49% in the arch, thoracic, and abdominal regions of the aorta. AGI-1067 also reduced vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) mRNA levels in lungs of lipopolysaccharide-stimulated mice. At the cellular level, AGI-1067 inhibited tumor necrosis factor-alpha-inducible expression of VCAM-1, MCP-1, and E-selectin in human aortic endothelial cells (IC50 values = 6, 10, and 25 microM, respectively). These data show that AGI-1067 can inhibit atherosclerosis not only via its lipid-lowering effects but also by having direct anti-inflammatory effects on the vessel wall and suggest that it may be a novel therapeutic agent for coronary artery disease. 相似文献
96.
The Nottingham prognostic index (NPI) is a widely adopted prognostic tool in breast cancer. The HER-2 oncogene overexpression is also associated with higher risk. The aim of our study is to investigate the correlation between the NPI and HER-2 in breast cancer. Two hundred and five patients with breast cancer managed in the Department of Surgery, University of Hong Kong Medical Centre, at Queen Mary Hospital between January 1995 and December 1997 were studied. This is a retrospective analysis of prospectively collected database. Variables evaluated for the analysis of prognostic significance included tumor size, axillary lymph node status, histological grade, estrogen and progesterone receptor status and HER-2 oncogene expression. NPI was calculated from tumor size, lymph node status and histological grade. In univariate analysis, tumor size, axillary lymph node status, distant metastasis status, HER-2 oncogene overexpression and NPI score were found to be significant variables. Significant poorer overall survival was also observed with higher NPI category and positive HER-2. Only tumor size and NPI category with subdivision by HER-2 status were independent factors in multivariate analysis . The combination of the HER-2 oncogene expression status with the widely adopted NPI provides a reliable way to predict prognosis in breast cancer patients. 相似文献
97.
BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies. 相似文献
98.
Anti-thrombotic therapy for non-rheumatic atrial fibrillation 总被引:1,自引:0,他引:1
Recent randomized trials of antithrombotic therapy in non-rheumatic atrial
fibrillation have helped to clarify the benefits of warfarin and aspirin.
Low-risk patients (normotensives aged <60 with normal left
ventricular function) have a small risk of thromboembolic events and are
unlikely to benefit significantly from anticoagulants, but may benefit from
aspirin with little increase in risk of bleeding. High-risk patients
(>75 years, impaired left ventricular function, previous
thromboembolism and/or associated conditions such as hypertension and
diabetes mellitus) have an increased risk of thromboembolism, and benefit
from long-term anticoagulant therapy to a greater degree than with aspirin,
although at a risk of increased bleeding complications.
相似文献
99.
Adapting to psychosocial and physical changes can trigger nonspecific somatic complaints and depression. Somatization has been noted in all societies and cultures; however, it is more frequently observed in Asian populations. This study used the Geriatric Depression Scale (GDS) to screen 100 Taiwanese American older adults for depressive symptoms and found that seven participants (7%) experienced depressive symptoms (GDS >/= 14). Although the mean number of illnesses reported was significantly higher (t = -16.8, P <.001) in the depressive group, the seven individuals did not focus on physical symptoms during interview. They reported guilt, sadness, anger, resentment, loneliness, helplessness, hopelessness, inability to enjoy activities, and anhedonia. If older adults are given the time to express themselves, they are able to reveal their emotional pain and distress rather than remain preoccupied with somatic complaints. A simple depression screening tool, such as the GDS, can help detect depression. 相似文献
100.
Serologic test for syphilis as a surrogate marker for human immunodeficiency virus infection among United States blood donors 总被引:2,自引:0,他引:2
GA Herrera ; EM Lackritz ; RS Janssen ; VP Raimondi ; RY Dodd ; J Aberle-Grasse ; LR Petersen 《Transfusion》1997,37(8):836-840
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases. 相似文献