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71.
对本实验室克隆的人急性早幼粒白血病细胞株HL-60及其抗维甲酸分化亚系HL-60/RA进行细胞增殖、细胞周期、分裂中期细胞染色体分布和G-显带核型分析。发现两者在倍增时间和细胞形态上基本一致。在细胞周期分布上,两者都具有肿瘤细胞的周期分布特征,但HL-60/RA细胞的S期细胞群少于HL-60细胞。两者染色体数量分布比较集中,染色体众数分别为45±3(HL-60)和45±1(HL-60/RA),呈近二倍体核型,G-显带核型分析表明两者都接近正常二倍体核型,都含较多的异常染色体。上述结果说明HL-60和HL-60/RA细胞的遗传学来源一致。 相似文献
72.
目的 对比观察头孢噻肟(CTX)与其他两种抗菌药物治疗方案对30例血液病合并感染患者杀 菌活性(SBA)及临床疗效。方法SBA采用微量稀释法测定,临床疗效根据临床治疗登记表按三 级标准判定。结果与结论 头孢噻肟的临床反应最佳,杀菌作用时间维持较长,但对绿脓假单胞 菌和阴沟肠杆菌杀菌作用较差;呱拉西林(PIP)与阿米卡星(AN)方案的抗菌谱广,但PIP杀菌 作用时间较短,可考虑缩短给药间期,而AN可按一日一次给全日量的方案,以提高疗效减少不 良反应;头孢哌酮(CPZ)可主要用于绿脓假单胞菌感染,也可用于其它细菌的混合感染,但给药 间隔时间以一日三次为宜。 相似文献
73.
For the treatment of intraabdominal infection, single-agent antimicrobial regimens such as β-lactams with good antianaerobic activity are frequent alternatives to combination regimens such as aminoglycosides or aztreonam plus an antianaerobic agent such as clindamycin or metronidazole. The major issues in selecting a regimen are relative efficacy, potential for adverse drug effects, and cost. Single agents are clearly equivalent to combinations in preventing infectious complications after penetrating abdominal trauma and in treating established intraabdominal infections of mild to moderate severity or in relatively low-risk patients. A few trials demonstrated their equivalency in patients at high risk of mortality, although experience is limited. Single-agent regimens may reduce the risks of adverse drug effects compared with combination regimens, but they are not always less expensive. 相似文献
74.
75.
Severe hypokalemia in thyrotoxic periodic paralysis 总被引:1,自引:0,他引:1
Donald Miller MD Jorge delCastillo MD Tat-Kin Tsang MD 《The American journal of emergency medicine》1989,7(6):584-587
Thyrotoxic hypokalemic periodic paralysis is an uncommon but sometimes fatal disease in which early recognition and therapy may prevent untoward complications. The case of a 26-year-old Chinese man who presented to the emergency department with rapidly progressive profound weakness and severe hypokalemia (serum potassium, 1.2 mEq/L) is presented. The patient required endotracheal intubation, ventilatory assistance, and intravenous potassium administration. Emergency medical evaluation and management of this entity are discussed. 相似文献
76.
Objective To investigate the effect and mechanism by which PPARγ ligand, rosiglitasone, regulates the expression of CD40 and intercellular adhesion molecule 1 (ICAM-1) in the rat peritoneal mesothelial cells (RPMCs) induced by lipopolysaccharide (LPS). Methods RPMCs were harvested from Sprague-Dawley rat peritoneal cavity and maintained under defined in vitro conditions. The cells were randomly divided into groups as follows: medium, LPS (5 mg/L), LPS (5 mg/L)+BAY11-7085(5 μmol/L, NF-κB inhibitor), rosiglitazone (10 μmol/L or 20 μmol/L, peroxisome proliferator-activated receptor γ activator), LPS (5 mg/L)+rosiglitazone (10 μmol/L)+GW9662 (3 μmol/L, peroxisome proliferator-aetivatcd receptor γ antagonist), and LPS (5 mg/L)+vehicle (DMSO 0.2 ml/L). The expressions of CD40 and ICAM-1 RNA in RPMCs were examined by RT-PCR after 3 hour treatment, and the protein expressions of CD40, ICAM-1, p-NF-κB p65 and p-IκBα were examined by Western blot or immunofluorescence after 24 hour treatment. Results Following treatment with LPS, both the expressions of CD40 and ICAM-1 protein in RPMCs were up-regulated significantly (P<0.05), and the phosphoralation of p65 was increased greatly (1.10±0.17 vs 0.55±0.06, P<0.05). BAY11-7085 (5 μmol/L) significantly decreased the protein expression of p-p65 (0.22±0.11 vs 1.10±0.17, P<0.01), CD40 (0.34±0.02 vs 0.50±0.06, P<0.05) and ICAM-1 (0.35±0.16 vs 0.74±0.03, P<0.05). Pretreated with rosiglitazone for 3 h then added with LPS for 1 h, the levels of p-p65, CD40 and ICAM-1 in RPMCs were significantly decreased compared with those of LPS group (0.77±0.08 vs 0.90±0.10, P相似文献
77.
Leeta Alison Green Khoi Nguyen Bijan Berenji Meera Iyer Eileen Bauer Jorge R Barrio Mohammad Namavari Nagichettiar Satyamurthy Sanjiv S Gambhir 《Journal of nuclear medicine》2004,45(9):1560-1570
Reporter probe 9-(4-18F-fluoro-3-[hydroxymethyl]butyl)guanine (18F-FHBG) and reporter gene mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39tk) have been used for imaging reporter gene expression with PET. Current methods for quantitating the images using the percentage injected dose per gram of tissue do not distinguish between the effects of probe transport and subsequent phosphorylation. We therefore investigated tracer kinetic models for 18F-FHBG dynamic microPET data and noninvasive methods for determining blood time-activity curves in an adenoviral gene delivery model in mice. METHODS: 18F-FHBG (approximately 7.4 MBq [approximately 200 microCi]) was injected into 4 mice; 18F-FHBG concentrations in plasma and whole blood were measured from mouse heart left ventricle (LV) direct sampling. Replication-incompetent adenovirus (0-2 x 10(9) plaque-forming units) with the E1 region deleted (n = 8) or replaced by HSV1-sr39tk (n = 18) was tail-vein injected into mice. Mice were dynamically scanned using microPET (approximately 7.4 MBq [approximately 200 microCi] 18F-FHBG) over 1 h; regions of interest were drawn on images of the heart and liver. Serial whole blood 18F-FHBG concentrations were measured in 6 of the mice by LV sampling, and 1 least-squares ratio of the heart image to the LV time-activity curve was calculated for all 6 mice. For 2 control mice and 9 mice expressing HSV1-sr39tk, heart image (input function) and liver image time-activity curves (tissue curves) were fit to 2- and 3-compartment models using Levenberg-Marquardt nonlinear regression. The models were compared using an F statistic. HSV1-sr39TK enzyme activity was determined from liver samples and compared with model parameter estimates. For another 3 control mice and 6 HSV1-sr39TK-positive mice, the model-predicted relative percentage of metabolites was compared with high-performance liquid chromatography analysis. RESULTS: The ratio of 18F-FHBG in plasma to whole blood was 0.84 +/- 0.05 (mean +/- SE) by 30 s after injection. The least-squares ratio of the heart image time-activity curve to the LV time-activity curve was 0.83 +/- 0.02, consistent with the recovery coefficient for the partial-volume effect (0.81) based on independent measures of heart geometry. A 3-compartment model best described 18F-FHBG kinetics in mice expressing HSV1-sr39tk in the liver; a 2-compartment model best described the kinetics in control mice. The 3-compartment model parameter, k3, correlated well with the HSV1-sr39TK enzyme activity (r2 = 0.88). CONCLUSION: 18F-FHBG equilibrates rapidly between plasma and whole blood in mice. Heart image time-activity curves corrected for partial-volume effects well approximate LV time-activity curves and can be used as input functions for 2- and 3-compartment models. The model parameter k3 from the 3-compartment model can be used as a noninvasive estimate for HSV1-sr39TK reporter protein activity and can predict the relative percentage of metabolites. 相似文献
78.
3种培养基体外培养人芽囊原虫的效果观察 总被引:1,自引:0,他引:1
目的 观察人芽囊原虫在 3种培养基中的生长繁殖情况 ,以探讨最佳的培养方法。 方法 从大学生粪便中分离人芽囊原虫 ,转种至 3种不同培养基 ,定时观察人芽囊原虫的生长繁殖情况 ,根据原虫密度评价培养效果。 结果培养 96h后 ,Locke’s鸡蛋血清 (LES)双相培养基中的人芽囊原虫密度最高 ,改良Jones单相液体培养基次之 ,Locke’s琼脂血清 (LAS)双相培养基原虫密度最低 ,差异有显著性 (P <0 .0 5 ) ;观察 3种培养基中的原虫密度高峰持续时间分别为 3 60h、96h和 72h ,最长存活时间分别为 5 5 2h、3 3 6h和 168h。 结论 Locke’s鸡蛋血清双相培养基较适用于人芽囊原虫体外增殖培养。 相似文献
79.
80.
程友琴 《中华老年多器官疾病杂志》2004,3(2):146-148
一氧化氮(NO)的发现,不仅揭示了内皮依赖舒张因子的化学本质,更重要的是发现了简单的气体分子作为机体内源性信号分子的事实,迄今,将内源性NO和一氧化碳(CO)从传统的神经转导信使和体液转导信使中区别出来,命名为"gasotransmitters,气体信使"[1],已为科学界接受. 相似文献