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871.
J E Kehoe  J M Daly  D J Straus  J J DeCosse 《Cancer》1985,55(6):1256-1264
A retrospective review of patients with non-Hodgkin's lymphoma (NHL) who underwent palliative splenectomy for splenomegaly, hypersplenism, or autoimmune complications was done. From 1970 through 1981, 46 patients had palliative splenectomy for splenomegaly alone (n = 3) or various hematologic abnormalities with (n = 35) or without (n = 8) splenomegaly. Splenectomy was performed for life-threatening (n = 7), severe (n = 15), or mild (n = 24) symptoms/signs. The most common hematologic abnormalities were thrombocytopenia (platelet count less than 120,000/mm3; n = 38) and/or anemia (hemoglobin level less than 11.0 g/mm3; n = 29). Response to splenectomy was defined as greater than a threefold increase in preoperative platelet count and/or an increase in hemoglobin levels to greater than 11.0 g/mm3 in the first postoperative month. Four patients with thrombocytopenia did not respond, whereas 33 patients responded with greater than a sevenfold increase in platelet count. All four nonresponders died of complications of thrombocytopenia or progressive disease. Eighteen of 28 (64%) patients with anemia responded to splenectomy. Larger spleens (2000 g versus 1410 g; P less than 0.05) and lower platelet counts (42,000 versus 75,000; P less than 0.05) were found in all nonresponding patients. Responders and nonresponders could not be distinguished on the basis of age, sex, race, duration of disease or splenic involvement, primary site of disease, histopathologic findings, bone marrow or lymphangiogram results, or prior chemotherapy and radiotherapy. Patients with mild symptoms/signs were more likely to respond hematologically than patients with life-threatening or severe symptoms/signs (86% versus 54%; P = 0.06). For all patients, 2- and 5-year survival from the time of splenectomy was 44% and 26%, respectively. Median survival was 18 months (range, 1-144 months). Inability to reverse hematologic abnormalities was associated with poor survival. All nonresponding patients died within 36 months of surgery, whereas 5-year survival in responding patients was 40%. Nine of 30 patients (30%) who responded hematologically survived longer than 5 years, but this group of patients could not be distinguished from the remaining patients on the basis of age, sex, race, duration of disease or splenic involvement, primary site of disease, histopathologic features, bone marrow or lymphangiogram results, or prior chemotherapy and radiotherapy. Surgery was well-tolerated (mortality, 9%; morbidity, 21%). All surgical mortalities and 78% of complications occurred in patients operated on for life-threatening or severe symptoms/signs.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
872.
The acquisition of the rabbit's nictitating membrane response to a tone and light compound and to its components was examined when compound presentations were reinforced at one conditioned stimulus-unconditioned stimulus (CS-US) interval and individual component presentations were reinforced at another CS-US interval. Examination of the time course of the CRs revealed that (a) despite the mixture of CS-US intervals, conditioned response (CR) timing remained accurate, that is, CRs reached their peaks at the alternative points of US delivery; (b) the momentary magnitude of the CR to the compound was predominantly an additive function of the CR magnitude to the individual components; but (c) there was modest evidence of differentiation between the compound as a unit and the individual components. The results are discussed in terms of their implications for the study of the neural substrates of temporal and sensory integration as they modulate CR acquisition.  相似文献   
873.
874.
Ifediba  TC; Stern  A; Ibrahim  A; Rieder  RF 《Blood》1985,65(2):452-455
Studies of the ability of Plasmodium falciparum to grow in vitro in the red blood cells of subjects with certain beta-thalassemia syndromes are often difficult to interpret because of the known inhibitory effect of an elevated cellular content of human fetal hemoglobin (HbF). P falciparum therefore was cultured in vitro in the erythrocytes of subjects with hemoglobin H (HbH) disease and various other alpha- thalassemia genotypes that are unaccompanied by increased levels of HbF. Growth of the malaria parasite was markedly retarded in HbH red blood cells, when compared with growth in blood from normal control subjects. No consistent impairment of growth was seen in the erythrocytes of subjects having deletion of only one or two alpha- globin genes. These results indicate that erythrocytes with a severe thalassemia phenotype provide a less hospitable growth environment for P falciparum than normally hemoglobinized red blood cells, even in the absence of increased levels of HbF.  相似文献   
875.
In 112 plateletphereses done by the Haemonetics blood processor, the comparative effectiveness of ACD formula A, ACD formula B, and 2 per cent citrate in saline was evaluated. With respect to yields of platelets and white blood cells (e.g., lymphocytes), ACD-B was significantly better than the other two. Both ACD-B and 2 per cent citrate gave a much lower incidence of citrate reactions in the donors than were encountered with ACD-A.  相似文献   
876.
The variable regions of five human immunoglobulin heavy chains of the V(H)III subgroup have been totally sequenced. Three of the heavy chains belonged to the IgG class and two to the IgA class. Examination of these sequences, and comparison with additional published heavy chain sequences, showed that a total of four hypervariable regions is characteristic of human heavy chain variable regions.The relatively conserved character of large segments of the heavy chain variable region was very evident in these studies. The conserved segments, which are those sections located outside the hypervariable regions, comprise approximately 65% of the total heavy chain variable region. The following general structural pattern for antibody molecules emerges from this and related studies: an overall combining region superstructure is provided by the more conserved segments while the refinements of the active site specificity are a function of hypervariable regions.  相似文献   
877.
878.
Percutaneous antegrade extrusion of ureteral stones   总被引:1,自引:0,他引:1  
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879.
880.
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