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991.
Long-term indwelling central venous catheters have eased the administration of drugs, blood products, and hyperalimentation to patients with cancer. However, their use is associated with thrombotic complications. We report here on the thrombotic complications prospectively observed in 46 patients with refractory lymphoma (22 Hodgkin's disease, 24 non-Hodgkin's lymphoma) who had placement of one or more catheters in preparation for autologous stem cell transplantation (ASCT). Thrombosis of 26 catheters in 19 patients was observed. Specific abnormalities of hemostasis were equally common in patients who developed thrombosis and in those who did not. Thrombotic complications were more common in patients with Hodgkin's disease (13/22) than in patients with non-Hodgkin's lymphoma (6/24, p = 0.04). Although more patients with Hodgkin's disease had received prior splenectomy and/or irradiation to the area involved by thrombosis than patients with non-Hodgkin's lymphoma, the incidence of splenectomy and irradiation was similar for patients with Hodgkin's disease who developed thrombosis and those who did not. Therefore, although the etiology remains unexplained, patients with Hodgkin's disease undergoing intensive chemotherapy and ASCT appear to have a higher incidence of catheter-related thrombosis than patients with non-Hodgkin's lymphoma undergoing similar therapy.  相似文献   
992.
Twenty patients with advanced malignant disease submitted to autologous bone marrow transplantation with marrow either unpurged (10 patients) or purged in vitro with mafosfamide (10 patients) after ablative chemotherapy, received simultaneously autologous peripheral blood stem cells (PBSC) collected during one to three 3 h cytapheresis procedures. The kinetics of the hematological recovery of these patients were compared to those of a group of patients suffering from similar diseases and grafted in the same institution with either unpurged marrow only (14 patients) or purged in vitro with mafosfamide (six patients). The median times to reach 10(9)/l leukocytes, 0.5 x 10(9)/l polymorphs, and 50 x 10(9)/l platelets were reduced by 10, 10, and 13 days, respectively, in patients transfused with both autologous bone marrow and peripheral blood stem cells as compared to those receiving bone marrow only. A reduction in the numbers of days spent in hospital post-transplantation (p less than 0.01), of days of fever greater than 38 degrees C (p = NS), and of platelet (p = 0.07) and of red blood cell transfusions (p less than 0.01) were also observed in the group of patients grafted with bone marrow and PBSC.  相似文献   
993.
The radiological findings in five patients with pelvic sort tissue neo plasms directly involving the sacroiliac joint, are described. All patients had Computed Tomography (CT) examinations, two of the patients also having Magnetic Resonance Imaging (MRI). The role of imaging in this uncommon entity is discussed as well as the importance of making this diagnosis, thereby excluding unilateral sacroiliitis. The therapeutic implications of this diagnosis relate to local neural involvement, especially the sciatic nerve, and the fact that involvement of the sacroiliac joint by tumors significantly compromises chances of a successful surgical outcome. The role of MR in this condition is not yet certain, but it may prove to be the method of choice in view of its excellent depiction of skeletal neo plasms.  相似文献   
994.
The influence of usual regimens of the H2 blocking drugs, cimetidine, ranitidine, and nizatidine on the steady-state plasma concentrations and pharmacokinetic characteristics of theophylline was studied in seventeen patients with chronic obstructive pulmonary disease (COPD). Patients were dosed to steady-state with an oral, sustained-release formulation of theophylline given in therapeutic doses twice daily for 2 weeks. Over the next 4 weeks, each patient received a week-long regimen of each H2 blocker concomitantly with theophylline, and a week-long regimen of theophylline alone (control). At the end of each of the latter 4 weeks the steady-state pharmacokinetics of theophylline were assessed. Neither ranitidine nor nizatidine treatment altered the steady-state pharmacokinetics of theophylline relative to the control phase (i.e. no H2 blocker treatment). Values for theophylline C(ave), Cssmax, AUC0-12, and CLoral were significantly different during cimetidine treatment compared with all other treatments (ranitidine, nizatidine, and control). Cimetidine increased theophylline Cssmax, AUC0-12 and Cave by approximately 32%, and decreased theophylline oral clearance by approximately 23%. The authors conclude that cimetidine alters the steady-state pharmacokinetics of theophylline in COPD patients, whereas ranitidine and nizatidine are without effect.  相似文献   
995.
ELISA for quantitation of L-selectin shed from leukocytes in vivo.   总被引:13,自引:0,他引:13  
L-selectin is a cell surface receptor on granulocytes, lymphocytes and monocytes that is responsible for the initial attachment of leukocytes to endothelium. The extracellular domain of L-selectin is proteolytically shed from leukocytes following cellular activation in vitro. The shed form of L-selectin (SL-selectin) is functionally active and at high concentrations can inhibit leukocyte attachment to endothelium. Therefore, an ELISA was developed to quantitate the levels of SL-selectin in biological fluids, biopsy specimens and during recombinant protein production. This simple, quantitative sandwich ELISA uses two monoclonal antibodies directed against the extracellular domain of SL-selectin. The assay has a detection range of 5-1300 ng/ml, is precise and sensitive. The ability of this assay to detect SL-selectin in serum, plasma, and culture supernatant fluid was demonstrated and it was used to quantitate circulating SL-selectin in normal and patient sera. Patients with sepsis and HIV infection showed markedly elevated SL-selectin levels in serum. Thus, the ELISA should prove useful both for laboratory purposes as well as in the diagnostic evaluation of patients with inflammatory diseases.  相似文献   
996.
Individuals and families with hereditary cancers have informational needs that differ, depending on the availability of testing for increased hereditary risk and major focus of concern (reproductive decision-making or risk to self). Cancer risk counseling helps individuals understand risk information so they can make decisions appropriate to their lives and value systems.  相似文献   
997.
A retrospective follow-up study to ascertain the relationship between the level of serum zinc and its rate of change during gestation and birthweight was conducted in 476 women of lower socioeconomic status. Serum zinc concentrations measured at approximately 16 (early) and 32 weeks (later) in gestation were both found to be significant predictors of birthweight. Even after controlling for gestational age at birth and other determinants of birthweight, for each microgram/dl increase in serum zinc early and later in pregnancy, birthweight increased by 5.8 and 8.6 g, respectively. Furthermore, after adjustment for initial zinc levels both the total change (beta = -7.0, P = 0.0007) and the rate of change (beta = -60.8, P = 0.007) in serum zinc during pregnancy were inversely associated with birthweight, i.e., the larger the fall in serum zinc during pregnancy, the smaller the infant. Low serum zinc level (less than 60 micrograms/dl) late in pregnancy was associated with greater than a five-fold increase in the odds (OR = 5.8, 95% CI = 1.8, 16.4) of giving birth to a low birthweight infant. The results of this study suggest a threshold for maternal serum zinc below which the prevalence of low birthweight increases rapidly.  相似文献   
998.
ABSTRACT. A child with respiratory distress was found to have been given an antibiotic which was reconstituted with methadone. A delay in standard emergency room management led to a delay in diagnosis and treatment.  相似文献   
999.
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