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101.
Patients with hairy cell leukemia (HCL) and chronic lymphocytic leukemia (CLL) were treated with recombinant interferon alpha A (rIFN- alpha A). The binding of iodinated recombinant interferon-alpha to baseline samples of peripheral blood mononuclear cells (PBMCs) from the leukemia patients was compared with clinical responsiveness to rIFN- alpha A. HCL patients (8/10) responded to rIFN-alpha A therapy, whereas none (0/10) of the CLL patients studied responded. The PBMCs from the eight responsive HCL patients bound approximately twice as much iodinated interferon as the PBMCs from nonresponsive CLL patients. This difference was due to more high-affinity receptors per cell with no difference in the affinity of the interferon-receptor interaction. However, because PBMCs from HCL patients were larger than PBMCs from CLL patients, the cell surface receptor density was similar. The leukemic cells from one of the two nonresponsive HCL patients bound iodinated interferon similarly to the cells from the responsive HCL patients, whereas the leukemic cells from the other nonresponsive HCL patient bound considerably less. The rapidity of response of the HCL patients did not correlate with the level of binding of iodinated interferon. Our results suggest that the absolute number of interferon receptors per cell may be only one of several important parameters in the response to rIFN-alpha A therapy, and that the responsiveness of a particular lymphoproliferative disease or a particular patient to rIFN- alpha A therapy cannot be predicted or explained solely by the degree of interaction between IFN and its cell surface receptor.  相似文献   
102.
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
103.
Zerez  CR; Lachant  NA; Tanaka  KR 《Blood》1986,68(5):1024-1029
Pyruvate kinase (PK)-deficient RBCs have several unexplained metabolic abnormalities, such as decreased concentrations of total adenine nucleotides (AMP, ADP, and ATP) and total (oxidized and reduced) nicotinamide adenine dinucleotide (NAD). Because 5-phosphoribosyl-1- pyrophosphate (PRPP) is an intermediate in the synthesis of adenine nucleotides and NAD, we investigated PRPP synthetase (PRPPS), the enzyme responsible for PRPP synthesis. This enzyme is regulated, in part, by changes in its state of subunit aggregation. The proportion of aggregated PRPPS can be altered in vitro by ATP and 2,3- diphosphoglycerate (DPG). Because PK-deficient RBCs have decreased ATP and increased DPG concentrations, we examined the state of subunit aggregation of PRPPS in RBCs from normal and PK-deficient subjects, using gel permeation chromatography. Young normal RBCs have more aggregated PRPPS than do older RBCs. In contrast, due to their decreased ATP and increased DPG concentrations, PK-deficient RBCs contain less aggregated PRPPS than do RBCs of comparable age without PK deficiency. These data suggest that PRPPS should be less active in vivo in PK-deficient RBCs. This may play a key role in mediating the decreases in total adenine nucleotide and total NAD concentrations in these RBCs.  相似文献   
104.
The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.  相似文献   
105.
Renal vein thrombosis in patients with nephrotic syndrome: CT diagnosis   总被引:1,自引:0,他引:1  
A retrospective evaluation of the computed tomography (CT) findings in 50 patients with the nephrotic syndrome was undertaken. In four patients with clinical manifestations of acute renal vein thrombosis (RVT) on initial examination, the diagnosis was confirmed by CT findings. Three patients had left RVT, one had right RVT, and all four had thrombus in the inferior vena cava (IVC) at the level of the renal veins. Of the remaining 46, otherwise asymptomatic patients, one had bilateral RVT, two had left RVT, and five had isolated IVC thrombus. The abnormalities noted on CT scans were widened renal vein(s) containing thrombus, thrombus in the IVC, renal enlargement, thickened Gerota fascia and formation of pericapsular venous collaterals, and an abnormal renal parenchymal enhancement pattern consisting of prolonged corticomedullary discrimination, delayed and/or persistent paraenchymal opacification, and delayed or absent pyelocalyceal visualization.  相似文献   
106.
107.
Computed equalization radiography: preliminary clinical evaluation   总被引:1,自引:0,他引:1  
Goodman  LR; Wilson  CR; Kim  CS 《Radiology》1993,186(2):399
  相似文献   
108.
To analyze the pathogenesis of B-cell lymphomas in patients with acquired immunodeficiency syndrome (AIDS), we studied two cell lines, Es I and Es III, established from one such lymphoma for the presence of sequences of the Epstein-Barr virus (EBV) and the human immunodeficiency virus [HIV; lymphadenopathy-associated virus (LAV/HTLV- III)] as well as for the presence of cytogenetic abnormalities and monoclonal rearrangements of immunoglobulin and T-cell receptor genes. Both cell lines expressed the same IgM, kappa phenotype as the original lymphoma. The karyotype of Es I was 46, XY, t(8;14), 2 p+, inv (6p), 17p-, and the cells of Es III had an additional i(7q). Immunoglobulin gene studies demonstrated the identical monoclonal rearrangements in both cell lines. Neither EBV nor HIV sequences were detectable in the malignant B cells at the genomic level, leading to the conclusion that mechanisms other than transformation by EBV or HIV may have contributed to the B-cell lymphoma in this patient and possibly also to the generally increased frequency in patients with AIDS.  相似文献   
109.
The contemporary pharmacological management of overactive bladder   总被引:2,自引:0,他引:2  
Overactive bladder (OAB) symptoms are an important cause of morbidity and interference in quality of life (QoL). This review considers the pertinent outcome measures currently in use in the evaluation of antimuscarinic therapy when used in the treatment of OAB symptoms. In particular, reference is made to the pivotal role of urgency and the difficulties associated with its assessment. The existing antimuscarinic agents are reviewed with particular reference to the third International Consultation on Incontinence committee's deliberations on this subject. The limitations of scientifically conducted meta-analyses are discussed. The importance of head-to-head comparative studies is emphasised with particular reference to the contemporary literature base of reported studies. Future work needs to be targeted at patient-perceived outcomes, and study design should include outcome measures that are more meaningful to people, such as return to bladder control, achievement of normal micturition frequency and QoL. Persistence rates with therapy need to be evaluated, with evaluation of the particular factors of importance in influencing the variation between the drugs, and more studies of the effects of antimuscarinics are required in older people.  相似文献   
110.
Although B cell leukemias and, recently, T cell leukemias can be identified both by surface marker and molecular analysis, there remains a population of acute undifferentiated leukemias (AUL) that cannot be allocated definitively to a single cell lineage. AUL was diagnosed in nine patients according to stringent criteria. We combined both immunologic and molecular approaches to analyze further the ambiguous origin of AUL cells. Southern blot analysis revealed rearranged Ig heavy-chain genes in seven patients and indicated a biclonal or oligoclonal leukemic cell population in three of them, including one case of AUL with translocation (4;11). Analysis of cell surface markers showed expression of at least one early B cell-associated antigen (BA- 1, BA-2, B4, UL-38) in six of these seven patients, with coexpression of a myeloid antigen (VIM-2) in three patients. Leukemic cells of two other patients neither exhibited Ig chain gene rearrangements nor expressed B cell-associated antigens. T cell receptor beta-chain genes showed germline configuration in all nine cases. Our results demonstrate heterogeneity among AUL patients based on molecular and surface marker analyses and suggest that most AUL blast cells are derived from a precursor cell that shares phenotypic and genotypic characteristics of early B cells with certain surface antigens of myeloid cells, in some cases of AUL more than one abnormal cell clone or subclone may exist, and the cellular origin, at least of some AULs exhibiting t(4;11), may be truly B cell lineage committed.  相似文献   
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