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541.
款冬花粗多糖体外诱导人白血病K562细胞的凋亡   总被引:1,自引:0,他引:1  
目的:观察款冬花粗多糖对体外培养人白血病K562细胞有无凋亡诱导作用。方法:实验于2006-06-25/2006-09-08在河北北方学院实验中心细胞生物学实验室、分子生物学实验室、药物研究实验室完成。①款冬花粗多糖的提取:称取已干燥粉粹的款冬花417.0g,加入1000mL体积分数0.85乙醇回流提取1h,滤过,滤渣加入1000mL三蒸水回流提取2h,过滤,滤渣再加入1000mL三蒸水回流提取2h,合并2次滤液,减压浓缩至适量,四倍体积无水乙醇醇沉,静置过夜,过滤,沉淀依次用无水乙醇、丙酮、石油醚洗涤,即得款冬花粗多糖。苯酚-硫酸法测定款冬花粗多糖含量以生药计算为122.9mg。制成102.5g/L粗多糖溶液。②人白血病K562细胞的生长抑制实验:体外培养的K562细胞经10,30,50,70,90mg/L的款冬花粗多糖作用48h后,通过Hoeehst33258染色在荧光显微镜下进行形态学观察、采用琼脂糖凝胶电泳及流式细胞术检测细胞凋亡。结果:①经款冬花粗多糖作用后,荧光显微镜下发现体外培养的K562细胞中出现核固缩、凋亡小体。②经不同质量浓度款冬花粗多糖处理的K562细胞DNA电泳均出现相差约200bp的DNA梯子状条带。③流式细胞仪检测发现,经不同质量浓度款冬花粗多糖处理的K562细胞,有凋亡峰。结论:款冬花粗多糖可诱导体外培养人白血病细胞K562凋亡。  相似文献   
542.
OBJECTIVE: To determine safe and appropriate alarm limits for the Marquette 8000 pulse oximeter to prevent hyperoxic and hypoxic episodes in neonates. It is necessary to define these limits for each brand of oximeter because of the variance in nonuser adjustable calibration algorithms used in pulse oximeters. METHODOLOGY: Oxygen saturation values obtained from a Marquette 8000 pulse oximeter (SpO2) were compared with simultaneous arterial blood gas PaO2 values obtained from blood gas analysis, for 322 samples in 24 consecutive neonates (median 30 weeks' gestation). RESULTS: In order to prevent 95% of hyperoxic episodes (PaO2 > 90 mmHg), the upper alarm limit was 95% SpO2. Similarly, to prevent 95% of hypoxic episodes (PaO2 < 40 mmHg), the lower alarm limit was 95% SpO2. A sensitivity lower than 95% had to be accepted to develop an alarm range which prevented both hyperoxic and hypoxic episodes. To maintain PaO2 values between 40 and 90 mmHg, an appropriate alarm range of 94-97% SpO2 (90% sensitivity, 28% specificity) was established. CONCLUSIONS: The relative merits of high sensitivity versus high specificity should be considered when determining appropriate alarm limits. Alarm limits which represent a balance between sensitivity and specificity will minimise false alarms and provide a clinically practical range. It would be useful for this type of information to be available for each brand of oximeter, to assist the user in determining appropriate alarm settings.  相似文献   
543.
Cross sectional data reporting the height, weight, and body mass index of UK patients with cystic fibrosis are presented. During the first decade of life height and weight in patients with cystic fibrosis are maintained at about 0.5 SD below those of the general population, which reflects an improvement over earlier published observations. Postpubertal stature and weight maintenance in the cystic fibrosis population still show substantial deficits which may be related to treatment.  相似文献   
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对291例颈动脉内膜剥脱术后患者进行随访研究,1例术后即期死亡;22例(6.3%)在术后发生脑中风,17例为中度中风,5例为严重中风,即期中风的病因包括:14例手术部位颈动脉血栓形成(14/22,64%),4例术中或术后即期脑栓塞,2例阻断颈动脉所致脑缺血,1例脑出血,1例原因不明。此外讨论了术后中风的危险因素和处理方法。  相似文献   
546.
BACKGROUND: Invasive aspergillosis (IA) is an important cause of morbidity and mortality among immunocompromised patients. Echinocandins are novel antifungal molecules with in vitro and in vivo activity against Aspergillus species. METHODS: We investigated the efficacy and safety of caspofungin in the treatment of IA. Ninety patients with IA who were refractory to or intolerant of amphotericin B, lipid formulations of amphotericin B, or triazoles were enrolled to receive caspofungin. RESULTS: Efficacy was assessed for 83 patients who had infection consistent with definitions of IA and who received >or=1 dose of study drug. Common underlying conditions included hematologic malignancy (48% of patients), allogeneic blood and marrow transplantation (25% of patients), and solid-organ transplantation (11% of patients). Seventy-one patients (86%) were refractory to and 12 patients (14%) were intolerant of previous therapy. A favorable response to caspofungin therapy was observed in 37 (45%) of 83 patients, including 32 (50%) of 64 with pulmonary aspergillosis and 3 (23%) of 13 with disseminated aspergillosis. Two patients discontinued caspofungin therapy because of drug-related adverse events. Drug-related nephrotoxicity and hepatotoxicity occurred infrequently. CONCLUSION: Caspofungin demonstrated usefulness in the salvage treatment of IA.  相似文献   
547.
The regulatory function of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) on granulocyte production in vivo was evaluated in an autologous bone marrow transplantation model using rhesus monkeys. Monkeys were exposed to 9.0 Gy total body irradiation and then transplanted with 5.0 x 10(7) low-density bone marrow cells/kg. Alzet miniosmotic pumps were subcutaneously implanted to deliver rhGM-CSF at a rate of 50,400 U/kg/d. Minipumps, containing either rhGM-CSF or saline, were implanted between zero and five days after transplantation for seven days. Kinetic recoveries of peripheral blood cells after either saline or rhGM-CSF treatment were compared. Treatment with rhGM-CSF accelerated the recovery of neutrophils. Neutrophils in rhGM-CSF-treated animals recovered to 80% (3.4 x 10(3)/mm3) pre-irradiation control levels by day 20, in comparison with only 33% (0.9 x 10(3)/mm3) recovery for saline control monkeys. In addition, the recovery of neutrophils was enhanced over that of the controls, reaching 140% v 70% on day 30. Another prominent feature of rhGM-CSF-treated monkeys was the accelerated recovery of platelets, reaching near 50% normal levels by day 24 in comparison with 20% of normal levels for controls. The infusion of rhGM-CSF was shown to be an effective regulator of early hematopoietic regeneration, leading to the accelerated recovery of both neutrophils and platelets and then providing a consistent sustained increase of neutrophils even in the absence of rhGM-CSF.  相似文献   
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