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841.
Lymphocyte depletion of donor bone marrow by counterflow centrifugal elutriation: results of a phase I clinical trial 总被引:1,自引:1,他引:0
Wagner JE; Donnenberg AD; Noga SJ; Cremo CA; Gao IK; Yin HJ; Vogelsang GB; Rowley S; Saral R; Santos GW 《Blood》1988,72(4):1168-1176
We report here the results of a phase I clinical trial using counterflow centrifugal elutriation (CCE) for the removal of donor T lymphocytes before allogeneic bone marrow transplantation (BMT). Thirty- eight patients received lymphocyte-depleted allografts from HLA- identical, MLR-nonreactive sibling donors. The patients entered onto the study were either at high risk on the basis of age (median, 39 years) or disease status (acute leukemia in early relapse [ER], chronic myelogenous leukemia [CML] in accelerated phase [AP], or therapy resistant [RES] lymphoma). All patients received a standard lymphocyte dose of 1 x 10(6) morphologic lymphocytes per kilogram ideal body weight (BW) and were maintained on cyclosporine A (CsA) for 170 days after BMT. Prompt engraftment occurred in 37 of 38 patients with a median time to absolute neutrophil count (ANC) greater than 500/microL of 18 days. Although acute graft-v-host disease (GVHD; clinical stage I or greater) was observed in 45%, it was limited to the skin in all but five patients. Survival was related to disease status at the time of BMT. Among patients with acute leukemia in first or second remission, CML in chronic phase (CP) or lymphoma in partial remission (PR), 64% are currently alive, in contrast to 31% of patients with acute leukemia in third remission or early relapse, CML in second CP or AP, or RES lymphoma. Median follow-up for all patients was 351 days (range, 105 to 711 days). We conclude that this procedure is safe and warrants further evaluation in a randomized efficacy trial. 相似文献
842.
843.
844.
Thirteen patients with biopsy-proved adenocarcinoma were prospectively examined with magnetic resonance (MR) imaging with use of a 1.5-T superconducting magnet. All patients subsequently underwent radical prostatectomy and careful, axial, histologic mapping of prostatic disease. Histologic findings were recorded on serial, axial diagrams to ensure precise pathologic correlation with the MR images. MR permitted identification of eight of 12 (67%) adenocarcinomas as hypointense foci (relative to the surrounding, higher intensity, peripheral zone); but tumor volume was under-estimated with MR imaging in five of eight cases (63%). Nodules of prostatic hyperplasia were identified correctly in only one of nine patients (11%). These findings suggest that, despite that fact that high field strength MR imaging currently does not depict all pathologic foci within the prostate, it may be of predictive value in the differential diagnosis of prostatic abnormalities when their locations are demonstrable. 相似文献
845.
Interleukin-6 and Epstein-Barr virus induction by cyclosporine A: potential role in lymphoproliferative disease 总被引:2,自引:0,他引:2
Posttransplant patients undergoing prolonged cyclosporine A (CsA) immunosuppressive therapy have been reported to have increased incidence of Epstein-Barr virus (EBV)-associated lymphoproliferative disorders. We undertook experiments to analyze the possible actions of CsA during EBV-infection of human peripheral blood mononuclear cells (PBMC). EBV-infected B cells cultured with CsA demonstrated increased EBV B-cell outgrowth as compared with those cultured without CsA. PBMC, after infection with EBV and CsA treatment, demonstrated increased interleukin-6 (IL-6) activity in the culture supernatant. The induction of IL-6 appears to differ within the various lymphocyte populations. In monocytes, IL-6 expression appears preferentially induced by EBV and is initiated by the binding of the two major virion glycoproteins, gp350 and gp220. Expression of IL-6 in T cells appears to be due mainly to CsA. B cells also express IL-6 after EBV exposure, but not after CsA treatment. EBV-immortalized B-cell lines cultured with CsA exhibited both an increased number of cells expressing viral lytic-cycle antigens and increased amounts of lytic-cycle proteins. IL-6, which is induced by CsA in PBMC, was also capable of inducing the lytic viral cycle in several EBV-immortalized cells. CsA, in promoting both increased numbers of lytic EBV B cells and an EBV paracrine factor, IL-6, within the microenvironment of EBV B cell:T cell and EBV B cell:monocyte interactions, may result in increased EBV B-cell immortalization and ultimately lead to the promotion of B-cell lymphomas in immunosuppressed patients. 相似文献
846.
Dextran microsphere embolization: experimental and clinical experience with radiologic-pathologic correlation. Work in progress 总被引:3,自引:0,他引:3
The radiologic and pathologic effects of canine renal embolization with dextran microspheres of two size ranges (40-150 micron and 100-300 micron) were studied 30 minutes and 1, 2, 4, and 6 weeks after embolization. Dramatic occlusions occurred with very small quantities of these particles, which reached more distally and were suspended and embolized more easily than other solid embolic agents. Because of these qualities, however, they should be used with more caution. They can be injected through 2-F catheters, calibrated-leak balloons, and open-ended guide wires. Embolization with dextran microspheres was also used for epistaxis, meningioma, dural arteriovenous malformation, renal tumors, bone metastasis, multiple myeloma, or peripheral angioma in ten patients. The technique was safe and effective, but special attention should be directed to proper dilution and gentle embolization with careful monitoring to avoid excessive embolization or reflux. 相似文献
847.
BACKGROUND & AIMS: Gastric mucosal hyperemia is a protective response mediated at least in part by the response of sensory afferent neurons to hydrogen ions. The aim of this study was to determine if other pathways to the hyperemic response are present and if these neurons have an effect exclusive of hyperemia on mucosal protection and repair. METHODS: Rat sensory afferent neurons were ablated by capsaicin treatment. Chambered stomachs were damaged by hypertonic saline followed by either acidic or neutral isotonic saline. Blood flow was measured by laser Doppler velocimetry, and mucosal morphology was quantitatively evaluated by microscopy. RESULTS: Mucosal damage alone evoked a strong hyperemic response in both control and ablated rats. Ablated rats lost gastric protection despite this hyperemic response. Acid exposure after damage sustained the hyperemic response. Rapid epithelial restitution occurred faster (even over hemorrhagic lesions) in control rats. CONCLUSIONS: The hyperemic response to mucosal damage alone is not mediated by sensory neurons. Protection of the stomach by sensory afferent neurons occurs by mechanisms also unrelated to their elicitation of hyperemia. Restitution during acid challenge is enhanced by the sustained hyperemic response mediated through sensory afferent neurons. (Gastroenterology 1996 Dec;111(6):1474-83) 相似文献
848.
Fracture nonunion: CT assessment with multiplanar reconstruction 总被引:2,自引:0,他引:2
Kuhlman JE; Fishman EK; Magid D; Scott WW Jr; Brooker AF; Siegelman SS 《Radiology》1988,167(2):483-488
Nineteen patients with suspected or possible fracture nonunion underwent computed tomography (CT) with multiplanar reconstruction (MPR). Each case represented a difficult problem in fracture management in which clinical and conventional radiographic examinations had failed to provide a definitive diagnosis. CT with MPR demonstrated nonunion in 13 of 19 cases by delineating the lack of bone bridging across the fracture site in multiple planes. Variable amounts bridging were detected in six cases, indicating partial healing or delayed union. Evaluation of fracture healing with MPR was possible despite remaining metal hardware (ten cases), multiple operations (15 cases), or bone grafting (five cases). CT with MPR aided surgical planning and affected treatment options by providing a more detailed assessment of malalignment and angular deformities, the magnitude of the gap in bone, and the integrity of the adjacent weight-bearing joints in multiple projections. It is an important new modality for evaluating fracture nonunion. 相似文献
849.
In vivo cell growth and pharmacologic determinants of clinical response in acute myelogenous leukemia 总被引:2,自引:1,他引:1
A predictable increase in the proliferative rate of malignant cells remaining after initial cytoreduction in vivo forms the rationale for timed sequential therapy (TST) with 1-B-D-arabinofuranosylcytosine (ara- C) for adult acute myelogenous leukemia (AML). The relationship between in vivo leukemic cell growth, intracellular ara-C metabolism, and clinical response to ara-C-containing TST was evaluated by comparing AML marrow cell growth kinetic and biochemical pharmacologic determinants obtained before therapy (day 0) and at the predicted peak of in vivo postdrug residual tumor proliferation (day 8). Serial measurements of DNA synthesis and net intracellular ara-C metabolism demonstrated marked increases in both determinants in day 8 residual tumor when compared with the pretreatment cells for newly diagnosed adults achieving complete remission but not for TST-refractory patients. The interrelationship of AML cell proliferation and biochemical pharmacology together quantitate cytotoxicity measured by both achievement and duration of remission and serve to predict eventual clinical outcome in response to TST with ara-C where both growth and favorable pharmacokinetics are intrinsic to the success of the drug schedule. 相似文献
850.
Left azygos lobe 总被引:1,自引:0,他引:1
Left azygos lobe is much rarer than right azygos lobe, but cases have been reported. Computed tomography proved more reliable than plain radiography in the diagnosis of left azygos lobe in a 10-year-old girl. 相似文献