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51.
肝癌特异性GGT诊断肝癌的研究进展   总被引:7,自引:0,他引:7  
  相似文献   
52.
卡托普利对大鼠t-PA和PAI-1活性的作用   总被引:1,自引:0,他引:1  
目的评价卡托普利对大鼠血浆t-PA和PAI-1活性水平的影响。方法给大鼠应用三种剂量的卡托普利,观察其对大鼠血浆t-PA和PAI-1活性水平的作用。结果卡托普利治疗后使大鼠血浆t-PA活性升高,PAI-1活性及PAI-1/t-PA活性比值显著降低,这种作用呈某种程度的剂量依赖性。结论卡托普利能增强大鼠纤溶系统的活性,这种作用呈某种程度的剂量依赖性。  相似文献   
53.
Chronic graft-versus-host (GVH) disease was induced in NZB/NZW F1 (B/W) hybrid female mice by the weekly injection of parental NZB spleen cells. Control mice received injections of syngeneic spleen cells only. The mice were assayed for antibodies to [3H]DNA and [3H]polyadenylic-polyuridylic acid by a cellulose ester filter radioimmunoassay, and for antibody to thymocytes by a cytotoxicity method. GVH disease accelerated the development of all three antibodies in B/W mice. In addition, sucrose density gradient ultracentrifugation of pooled sera suggested that an accelerated switch from 19S to 7S anti-DNA production may be an early effect of GVH. The mechanism of acceleration is discussed in terms of immunological and viral factors generated by the GVH reaction.  相似文献   
54.
Improved outcome in adult B-cell acute lymphoblastic leukemia   总被引:11,自引:6,他引:11  
A total of 68 adult patients with B-cell acute lymphoblastic leukemia (B-ALL) were treated in three consecutive adult multicenter ALL studies. The diagnosis of B-ALL was confirmed by L3 morphology and/or by surface immunoglobulin (Slg) expression with > 25% blast cell infiltration in the bone marrow (BM). They were characterized by male predominance (78%) and a median age of 34 years (15 to 65 y) with only 9% adolescents (15 to 20 y), but 28% elderly patients (50 to 65 y). The patients received either a conventional (N = 9) ALL treatment regimen (ALL study 01/81) or protocols adapted from childhood B-ALL with six short, intensive 5-day cycles, alternately A and B. In study B-NHL83 (N = 24) cycle A consisted of fractionated doses of cyclophosphamide 200 mg/m2 for 5 days, intermediate-dose methotrexate (IdM) 500 mg/m2 (24 hours), in addition to cytarabine (AraC), teniposide (VM26) and prednisone. Cycle B was similar except that AraC and VM26 were replaced by doxorubicin. Major changes in study B-NHL86 (N = 35) were replacement of cyclophosphamide by ifosphamide 800 mg/m2 for 5 days, an increase of IdM to high-dose, 1,500 mg/m2 (HdM) and the addition of vincristine. A cytoreductive pretreatment with cyclophosphamide 200 mg/m2, and prednisone 60 mg/m2, each for 5 days was recommended in study B-NHL83 for patients with high white blood cell (WBC) count (> 2,500/m2) or large tumor burden and was obligatory for all patients in study B-NHL86. Central nervous system (CNS) prophylaxis/treatment consisted of intrathecal methotrexate (MTX) therapy, later extended to the triple combination of MTX, AraC, and dexamethasone, and a CNS irradiation (24 Gy) after the second cycle. Compared with the ALL 01/81 study where all the patients died, results obtained with the pediatric protocols B-NHL83 and B-NHL86 were greatly improved. The complete remission (CR) rates increased from 44% to 63% and 74%, the probability of leukemia free survival (LFS) from 0% to 50% and 71% (P = .04), and the overall survival rates from 0% to 49% and 51% (P = .001). Toxicity, mostly hematotoxicity and mucositis, was severe but manageable. In both studies B-NHL83 and B-NHL86, almost all relapses occurred within 1 year. The time to relapse was different for BM, 92 days, and for isolated CNS and combined BM and CNS relapses, 190 days (P = .08). The overall CNS relapses changed from 50% to 57% and 17%, most probably attributable to the high-dose MTX and the triple intrathecal therapy. LFS in studies B-NHL83 and B-NHL86 was significantly influenced by the initial WBC count < or > 50,000/microL, LFS 71% versus 29% (P = .003) and hemoglobin value > or < 8 g/dL, LFS 67% versus 27% (P = .02). Initial CNS involvement had no adverse impact on the outcome. Elderly B- ALL patients (> 50 years) also benefited from this treatment with a CR rate of 56% and a LFS of 56%. It is concluded that this short intensive therapy with six cycles is effective in adult B-ALL. HdM and fractionated higher doses of cyclophosphamide or ifosphamide seem the two major components of treatment.  相似文献   
55.
56.
Small (1.5 cm or less) liver metastases: US-guided biopsy   总被引:2,自引:0,他引:2  
  相似文献   
57.
Changes in the relative arterial flow to hepatic tumors and adjacent normal liver, in response to varied doses of hepatic arterial epinephrine, were studied with single photon emission computed tomography. In 18 patients with known hepatic tumors, hepatic artery perfusion scans were obtained with the concurrent infusion of technetium-99m-labeled macroaggregated albumin and escalating doses of epinephrine (0-10 micrograms/min). Regions of interest were drawn around tumor and adjacent normal liver in three planes, and the average tumor-to-liver ratio (T:L) was calculated. In all 18 patients, there was a measurable baseline T:L perfusion advantage (range, 1.7-18.7; mean, 4.8). In 12 of 18 patients, this ratio increased with epinephrine (range, 1.1-53.6 times the baseline value; mean, 7.1). In six patients, no improvement in T:L could be demonstrated. In 14 patients the lung shunt index, a measurement of arteriovenous shunting, increased with escalating doses of epinephrine. This pilot study suggests that the infusion of epinephrine may improve the therapeutic index of certain regional therapies such as bolus drug infusions, hepatic arterial embolization, and radioactive microsphere therapy.  相似文献   
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60.
人白血病HL60细胞的分化状态对细胞凋亡的影响   总被引:2,自引:0,他引:2  
用细胞培养和流式细胞术等方法,研究人白血病HL60细胞诱导分化后,对三尖杉酯碱(Har)和喜树碱(Cam)诱导细胞凋亡的影响。结果表明,12-豆蔻酰及13-乙酸佛波酯以16nmol·L-1浓度处理HL60细胞24h,细胞向单核/巨噬细胞方向分化,阻断于G1期;分化细胞抗Har和Cam诱导的细胞凋亡,但其c-myc基因的表达无变化。1.4%二甲基亚砜处理HL60细胞48h,细胞向粒细胞方向分化,阻断于G1期;分化细胞抗Cam,而不抗Har诱导的细胞凋亡;分化细胞的c-myc基因表达明显下降。结果提示,人白血病HL60细胞的分化状态,明显影响三尖杉酯碱和喜树碱诱导的细胞凋亡,但可能与c-myc基因的表达变化无关。  相似文献   
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