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71.
The clinical significance of interleukin 2 receptor (IL2R) concentrations in serum was determined for 344 children with newly diagnosed acute lymphoblastic leukemia (ALL). Serum levels of IL2R in patients (267 to 80,000 U/mL, median 2,007 U/mL) were significantly higher than normal control values (170 to 738 U/mL, median 347 U/mL) (P less than .0001). Measurements in cases of T cell ALL were lower than in the non-T, non-B cases (P = .02). Among the 264 patients with non-T, non-B ALL, but not in those with T cell disease, higher serum IL2R levels (greater than 2,000 U/mL) were associated with a poorer treatment outcome (P = .04). In a multivariate analysis, serum IL2R level contributed independent prognostic information beyond that conveyed by leukocyte count, race, and age (P = .04). One explanation for these results is that soluble IL2R competes with normal lymphocyte- integrated IL2R for the ligand and thus could suppress host antitumor immunity.  相似文献   
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为寻找高效低毒的间日疟根治药,合成了7个2-甲基-5-取代苯氧基伯氨喹Ⅱ1~7,以与强效的4-甲基取代类似物比较,探索构效关系。初步生物评价结果表明,化合物Ⅱ1~7对鼠疟Plasmodium berghei的抑制性治疗作用及对鼠疟P.yoelii的病因性预防作用均明显弱于其4-甲基对应物,略低于伯氨喹。  相似文献   
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Traumatic brain stem injury: MR imaging   总被引:9,自引:0,他引:9  
Gentry  LR; Godersky  JC; Thompson  BH 《Radiology》1989,171(1):177-187
Eighty-seven patients with acute (n = 70) or chronic (n = 17) head injuries were prospectively studied with magnetic resonance (MR) imaging and computed tomography (CT) to characterize the frequency and nature of traumatic brain stem injury (BSI). Forty-eight traumatic lesions were identified in 36 patients. Of 36 patients, 35 had neurologic findings that corroborated the radiographic impression of BSI. T1- and T2-weighted MR images demonstrated a significantly higher number of lesions than did CT. Patients with BSI had a significantly higher frequency of corpus callosum and diffuse axonal "shear" lesions. The number of cortical contusions and extraaxial hematomas was similar in both groups. The mean Glasgow Coma Scale (GCS) scores at admission were significantly lower in patients with evidence of BSI on MR images. Patients with primary BSI had lower initial GCS scores, a longer duration of coma, more diffuse axonal "shear" lesions, and a higher frequency of corpus callosum injury than patients with secondary BSI. The location of primary and secondary lesions was significantly different. Overall, MR imaging was more helpful than CT in detecting, localizing, and characterizing BSI.  相似文献   
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赛庚啶对氧自由基的清除作用   总被引:18,自引:0,他引:18  
辛洪波  张宝恒 《药学学报》1993,28(3):161-165
赛庚啶(Cyp)对Fenton反应生成的·OH有较强的直接清除作用(EC50为54μmol/L),并明显抑制·OH的生成速率(IC50为22 μmol/L),且作用明显比·OH特异性清除剂甘露醇强(其EC50和IC50分别为22.7 mmol/L和10.7mmol/L)。Cyp对大鼠腹腔多形核白细胞(PMNs)产生的O2也有一定的清除作用,其IC50为179 μmol/L。提示Cyp的抗心肌损伤作用可能至少部分与其清除氧自由基作用相关。  相似文献   
78.

Background  

Synthetic- and naturally derived- biodegradable polymers have been widely used to construct scaffolds for cartilage tissue engineering. Poly(lactic-co-glycolic acid) (PLGA) are bioresorbable and biocompatible, rendering them as a promising tool for clinical application. To minimize cells lost during the seeding procedure, we used the natural polymer fibrin to immobilize cells and to provide homogenous cells distribution in PLGA scaffolds. We evaluated in vitro chondrogenesis of rabbit articular chondrocytes in PLGA scaffolds using fibrin as cell transplantation matrix.  相似文献   
79.
雷酚内酯的结构修正   总被引:2,自引:0,他引:2  
雷公藤别名黄藤,系卫矛科植物雷公藤(Tripterygium wilfordii Hook.f.)。其根有舒筋活血,祛风湿,消肿止痛的功效,多用于类风湿关节炎的治疗。根皮中含有生物碱、甙、萜以及其它成分,其中多种二萜内酯成分有抗肿瘤活性和免疫  相似文献   
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BACKGROUND/PURPOSE: This report reviews our experience using peritoneal drainage (PD) as initial therapy for intestinal perforation in premature infants with and without necrotizing enterocolitis (NEC). METHODS: A chart review was conducted of 18 consecutive premature infants who underwent PD for intestinal perforation from 1995 to 1998. Infants were divided into two groups. Group 1 consisted of eight infants who had intestinal perforation without evidence of NEC. Group 2 consisted of 10 infants who had perforation associated with evidence of NEC. A cohort of 10 infants with intestinal perforation treated with primary laparotomy between 1990 and 1995 was identified by chart review for historical control. RESULTS: All infants improved immediately after PD. In group 1, all survived. Seven (88%) recovered systemically after PD. Of these, five (63%) never required laparotomy. Two (25%) required delayed laparotomy. One infant (12%) failed to continue to improve 48 hours after PD and underwent urgent laparotomy and recovered. In group 2, eight (80%) infants survived. Six (60%) recovered from NEC after PD, but five required delayed laparotomy for obstruction or persistent drainage. Four infants (40%) failed to progress from their initial improvement after PD. Three underwent laparotomy; two recovered and one had total intestinal necrosis and died. The fourth infant died without exploration and total intestinal necrosis was discovered during autopsy. Thus, seven of eight survivors (88%) in group 2 required laparotomy at some point in their course. CONCLUSIONS: In premature infants with intestinal perforation, PD allows acute improvement and usually systemic recovery. In infants without evidence of NEC, PD may afford definitive treatment. In contrast, infants with evidence of NEC will likely require laparotomy, but initial PD may allow systemic stabilization and recovery of much of the involved intestine before laparotomy.  相似文献   
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