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991.
A H Filipovich D Vallera P McGlave D Polich K Gajl-Peczalska R Haake L Lasky B Blazar N K Ramsay J Kersey 《Transplantation》1990,50(3):410-415
Twenty-nine patients with advanced leukemias (median age 34 years) received histocompatible sibling marrow that had been depleted of T cells by ex vivo incubation with anti-CD5 monoclonal antibody-ricin immunotoxin (T101-R) for the purpose of graft-versus-host disease prophylaxis. Donor cell engraftment was documented in 28/29 patients by DNA restriction fragment length polymorphisms. In this pilot study the dose of T101-R incubated with donor marrow was increased in a stepwise manner from 300 ng (10 patients) to 600 ng (5 patients) to 1000 ng immunotoxin (IT)/10(7) bone marrow mononuclear cells (14 patients) in an attempt to achieve more effective GvHD prophylaxis. A statistically significant reduction in acute GvHD was achieved for patients receiving marrow pretreated with 1000 ng of immunotoxin (34%) compared to recipients of BM treated with 300 ng immunotoxin (100%, P = 0.0004). T-depleted marrow samples were evaluated for residual T cell activity using several in vitro assays including proliferation to the purified mitogen PHA (HA-17) and in mixed lymphocyte culture (MLC), T cell cytotoxicity, a limiting dilution assay for detecting precursors of proliferating T cells (LDApPTL), and phenotypic analysis of viable T cells expanded in 16-day culture with interleukin 2. The extent of T cell depletion determined by LDA assay varied widely at each immunotoxin concentration used. Thus, there was no correlation between the dose of T cells infused and subsequent GvHD. Phenotyping of lymphocytes recovered from immunotoxin-treated marrow demonstrated that residual T cells were CD5 negative in all cases tested. The only in vitro parameter that predicted subsequent acute or chronic GvHD was the demonstration of viable CD5 negative lymphocytes with T cell phenotype (CD2, CD3, and/or CD7 positive) after 16-day culture with IL-2 of the T-depleted bone marrow. We observed that such CD5 negative cells expressing other T cell markers have cytotoxic function and speculate that these cells may be capable of mediating GvHD in allogeneic transplantation. 相似文献
992.
The flow cytometric crossmatch and early renal transplant loss 总被引:3,自引:0,他引:3
R J Mahoney K A Ault S R Given R J Adams A C Breggia P A Paris G E Palomaki S A Hitchcox B W White J Himmelfarb 《Transplantation》1990,49(3):527-535
Data from this retrospective study indicate that a positive two-color T and/or B cell flow cytometric crossmatch (FCXM) is predictive of early renal allograft loss (less than 2 months) in cadaveric kidney donor recipients who had a negative crossmatch by the antihuman globulin complement-dependent cytotoxicity technique. Among 90 cadaveric kidney donor recipients (67 primary, 23 regrafts), 14 (8 primary, 6 regrafts) lost their renal allografts within 2 months, and 10 of the 14 were FCXM positive and HLA sensitized. The remaining 76 allografts survived beyond 2 months, 12 of which were FCXM-positive. Thus, the FCXM sensitivity rate for detecting early graft loss was 71%, and the specificity rate was 84%. Cadaveric graft-loss rates at 2 months were 33% for primary and 60% for FCXM-positive regrafts in contrast to 7% for primary and 0% for FCXM-negative regrafts. The difference in early graft loss between FCXM-positive and FCXM-negative recipients was statistically significant (P less than 0.0001). Subset analyses of FCXM-positive graft recipients indicate: (1) previous early graft loss contraindicates transplantation of an FXCM-positive regraft (P = 0.03); and (2) panel reactive antibody (PRA) less than or equal to 10% at crossmatch is not associated with early graft loss (P = 0.04). There was no significant difference in 1-year graft survival between primary and regrafts in either FCXM-negative recipients (85% vs. 77%, respectively) or FCXM-positive recipients (67% vs. 40%). All 12 of the FCXM-positive primary and regrafts that survived 2 months continued to function at 2 years. Stepwise logistic regression analysis of 5 independent predictor variables (FCXM status, gender, primary vs. regraft status, PRA level, and HLA mismatched antigens) indicated that the FCXM test was the best predictor of early graft loss. When FCXM results of the 90 cadaveric graft recipients were ranked in three groups, an FCXM channel shift of 29 or greater (third tertile) on a 1024 channel log scale was associated with a 7.0-fold (95% confidence interval 1.9-25.5) increased risk of early graft failure when compared to the first two tertiles. These data indicate that the FCXM offers an additional approach for identifying sensitized patients at risk of early renal allograft loss. 相似文献
993.
994.
This retrospective study was made to evaluate the significance of different sports activities that cause variable haemarthrosis with intraarticular lesions of the knee joint. Throughout 1984 to 1988 arthroscopy was performed in 337 patients with acute haemarthrosis. The average time between trauma and arthroscopy was 8 days. ACL rupture was diagnosed in most of these cases. Regarding the different types of sport activities ACL lesions were found in skiers (74%), other winter sports (47%), soccer (53%), tennis and squash (58%), athletics (41%) and indoor (61%). Peripheral meniscus tears associated with haemarthrosis were found in 36% and patellar dislocations in 8%. Isolated MCL ruptures were diagnosed clinically and arthroscopy was not performed in these cases. Throughout 1987 isolated ACL ruptures were fixed by reattachment. This technique was not continued any longer and ACL replacement by patellar tendon as bone-ligament-bone was performed routinely since 1988 in those patients, who required surgery. 56 patients required ACL reconstruction following conservative treatment because of ACL deficiency, when they went back to sports activities. Longitudinal peripheral meniscus tears were fixed by the scape in inside-out technique. 相似文献
995.
996.
Argon laser pretreatment in Nd: YAG iridotomy 总被引:1,自引:0,他引:1
Argon laser pretreatment prior to Nd:YAG laser iridotomy may decrease the incidence of operative hemorrhage. In a prospective, randomized clinical trial involving 12 patients (24 eyes), one eye was randomly assigned treatment with the Nd:YAG laser alone, while the other eye was pretreated with argon laser photocoagulation immediately prior to Nd:YAG laser. Eight of the 12 eyes (67%) treated with Nd:YAG laser alone had operative hemorrhages; only 2 of the 12 (17%) pretreated eyes did. Thus, argon laser pretreatment significantly reduced the incidence of hemorrhage during Nd:YAG iridotomy (P = .012). 相似文献
997.
998.
Two surgically cured cases of subependymoma with emphasis on magnetic resonance imaging 总被引:1,自引:0,他引:1
The authors describe two surgically cured cases of symptomatic subependymomas located in the lateral ventricle and septum pellucidum with emphasis on magnetic resonance imaging study. Both computed tomography and MRI revealed a calcified mass with repeated intratumoral hemorrhages. Cerebral angiograms disclosed rather hypovascular lesions. The histologic diagnosis was proven to be of subependymoma. The pertinent literature of surgically treated subependymomas is reviewed, and the characteristic biologic features are also discussed. 相似文献
999.
The records of 15 patients with Stage B3 or B2/C germ cell testis tumors who underwent full surgical debulking of a residual mass after completion of chemotherapy were reviewed retrospectively to look for predictors of residual mass histology. The density, character, and change in volume of the retroperitoneal mass on computerized tomography before and after chemotherapy were compared with the histology in the primary tumor and in the residual mass. One of 6 patients without teratoma in the primary tumor had a 97 percent reduction in the mass which contained residual teratoma. Two patients with residual seminoma had a 50 percent decrease in tumor volume, and both patients died of tumor progression despite salvage chemotherapy. Two patients with pure seminomas had only residual fibrosis in masses that decreased in volume by 77 and 75 percent, respectively. One of these masses was discrete and the other was diffuse. Seven of 9 patients (78%) with teratoma in the primary tumor had either teratoma (4 of 9, 44%) or carcinoma (3 of 9, 33%) in the residual mass, and the change in mass volume ranged from a 93 percent decrease to a 540 percent increase in size. All 7 patients with residual teratoma and/or carcinoma remain free of disease after observation or further chemotherapy. For the entire series, the mass density and character did not correlate consistently with the primary tumor or residual mass histology. Residual fibrosis alone or teratoma and/or carcinoma were seen with least (0 to 50%) and greatest (more than 90%) decreases in mass volume. 相似文献
1000.
R Shiroki M Izumitani Y Tsukiashi S Saito K Ishiguro Y Fujioka I Nagakubo 《Hinyokika kiyo. Acta urologica Japonica》1990,36(11):1385-1388
Vasopressin, a hormone secreted from the posterior lobe of the hypophysis, has endocrinological and antidiuretic effects; it contracts vessels and smooth muscles, especially intestinal smooth muscle. In the present study, we investigated the role of vasopressin (Pitressin: arginine-vasopressin) in elimination of intestinal gas on excretory urography reading. Sixty outpatients were randomly divided into six groups. In Group I, the routine procedure was employed, i.e. laxatives the previous night and NPO the morning of the examination. In Groups II to VI, different dose regimens were employed: 6 or 10 units of Pitressin was administered by subcutaneous injection 30 minutes prior to injection of a contrast medium, with or without NPO. Intestinal gas elimination was evaluated by X-ray films taken before and after injection of Pitressin. The efficacy was rated by four grades. There were no significant differences in the gas elimination or occurrence of side effects between any two groups. Younger patients seemed to respond quickly to Pitressin and good effects were obtained. These results indicate that the pretreatment for excretory urography with 6 units of Pitressin without NPO may be a safe and effective alternative method for elimination of intestinal gas, in particular for young patients. 相似文献