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53.
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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55.
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
56.
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
57.
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
58.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot. 相似文献
59.
In vitro and in vivo activity of murine lymphokine-activated killer cells after cryopreservation 总被引:1,自引:0,他引:1
The in vitro and in vivo effects of cryopreservation on the cytotoxic activity of murine lymphokine-activated killer (LAK) cells were studied. LAK cells were generated by incubation of spleen lymphocytes of BALB/c mice for 3 days with recombinant interleukin-2 (rIL-2) and subsequent cryopreservation. Cytotoxicity was determined in a 51Cr release assay. After thawing, cytotoxic activity was reduced (40.4% 51Cr release at an effector:target cell ratio of 40:1 as compared to 68.5% 51Cr release before freezing) and could be restored to precryopreserved levels by reincubation with rIL-2 for 2 days after thawing (78.8% 51Cr release). These cells were then tested in BALB/c mice injected with RAW 112 cells, a pre-B-cell lymphoma line. The results demonstrate that the survival rate of mice injected with cryopreserved and restimulated LAK cells (50% survival greater than 180 days after injection) did not differ significantly from that of mice injected with fresh unfrozen LAK cells (60% survival greater than 120 days, 50% survival greater than 180 days). Cryopreserved LAK cells have potential use in adoptive immunotherapy. 相似文献
60.
Chalmers RM; Howard RS; Wiles CM; Hirsch NP; Miller DH; Williams A; Spencer GT 《QJM : monthly journal of the Association of Physicians》1996,89(6):469-476
Twenty-nine patients with a neuronopathic or neuropathic disorder were
referred for assessment of respiratory insufficiency between 1978 and 1994.
Diagnoses included spinal muscular atrophy (6), chronic idiopathic
demyelinating neuropathy (4), Vialetto-van Laere syndrome (3), hereditary
motor and sensory neuropathy (3) and a miscellaneous group (5). We also
describe seven patients with Guillain-Barre syndrome (GBS) who required
long-term ventilatory support for over 6 months to 7 years after the
initial illness. Respiratory insufficiency occurred as a consequence of
respiratory muscle weakness, impaired bulbar function and restrictive lung
defects. In some groups presentation was with progressive nocturnal
hypoventilation culminating in acute respiratory failure. Five patients
with GBS or chronic idiopathic demyelinating neuropathy were weaned from
ventilatory support up to 18 months after the initial illness. The
remaining 24 patients required continuous or nocturnal ventilatory support
using intermittent positive-pressure ventilation (13), negative pressure
ventilation (4), nasal-mask-delivered intermittent positive-pressure
ventilation (4), nasal-mask-delivered continuous positive-pressure
ventilation (3), mouthpiece-assisted ventilation by day (2) and rocking bed
(1). None have been weaned from support after a period of ventilation
ranging from one month to 10 years. Eight patients have subsequently died.
相似文献