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71.
Kalpana Agarwal Anita Mukherjee Archana Sharma Ramesh Sharma Kuldip Raj Bhardwaj Soumitra Sen 《Environmental and molecular mutagenesis》1992,19(4):323-326
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo. 相似文献
72.
Age, hematopoietic growth factors, cyclosporin A, mode of bone marrow transplantation (BMT) (autologous, allogeneic-related,
unrelated), and underlying disease were assessed as potential risk factors for capillary leakage syndrome (CLS) in 96 patients
after BMT. CLS was defined as unexplained weight gain of >3% within 24 h and nonresponsiveness to furosemide. CLS occurred
in 9/21 patients after unrelated compared with 2/33 after allogeneic-related BMT (p=0.0017) for hematopoietic disorders (n=54) and in 6/7 patients after allogeneic-related compared with 3/35 after autologous BMT (p=0.0001) for solid tumors (n=42). Hematopoietic growth factors and cyclosporin A were no signficant risk factors on their own. We conclude that unrelated
BMTs or high-intensity conditioning regimens used in combination with allogeneic-related BMT are the main risk factors for
CLS.
Received: 6 January 1997 / Accepted: 10 March 1997 相似文献
73.
Bronchial hyperresponsiveness (BHR) and damage of the epithelium, as well as eosinophilia in the airway wall, induced by trimellitic anhydride (TMA) in sensitized brown Norway rats were studied. Rats were challenged once or seven times with aerosol of TMA conjugated to rat serum albumin (TMA-RSA) 3 weeks after intradermal TMA sensitization. Airway responsiveness (-log PC300 of acetylcholine i.v.) was measured 24 h after allergen challenge. Epithelial lesion and eosinophil infiltration in the airway walls were quantified under light microscopy, and TMA-specific IgE and IgG in serum were evaluated with ELISA. High levels of TMA-specific IgE and IgG were found in all rats in the sensitized groups compared to nonsensitized groups ( P < 0.001). Repeated allergen challenges of 0.03% TMA-RSA for 7 consecutive days enhanced the level of TMA-specific IgG, compared to single challenge ( P < 0.05). Single allergen challenge of 0.3% TMA-RSA had a nonsignificant tendency to produce BHR in sensitized rats compared to nonsensitized rats ( P =0.06). However, repeated allergen challenges (0.003% and 0.03% TMA-RSA for 7 consecutive days) produced significant BHR in sensitized rats ( P < 0.05). Furthermore, repeated low-dose (0.003%) TMA-RSA challenge produced more BHR than a 10 times higher single dose (0.03%) ( P < 0.05). Slight damage of the airway epithelium was seen in sensitized and repeat-challenged groups. However, bronchial eosinophilia was found in the sensitized and single-challenged groups, but not in nonsensitized nonchallenged, and sensitized repeat-challenged groups ( P < 0.005). We conclude that the brown Norway rat can be sensitized with TMA, and that repeated low-dose allergen challenges produce slight epithelial damage and BHR which is independent of ongoing eosinophilia in the airway wall. 相似文献
74.
Christine Boutin John Dyck Lee Benson Christine Houde Robert M. Freedom 《Pediatric cardiology》1992,13(3):176-177
Summary Balloon atrial septostomy is an established method of palliation for several forms of congenital heart disease. Previously performed under fluoroscopic x-ray control, recent reports have demonstrated the utility of transthoracic echocardiographic monitoring. We report the first application of uniplane transesophageal echocardiography (TEE) (6.7-mm probe) as an alternative imaging modality for control of ballon atrial septostomy on neonates in the intensive care unit. 相似文献
75.
We have previously established a cell damage model, with damage induced by either acid or pepsin treatment for 30 min, involving a rat gastric epithelial cell line (RGM1). In the present study, pretreatment of cells with epidermal growth factor (EGF; 0.1–10ng/mL) or sucralfate (0.1–3 mg/mL) for 4 h prevented such cell damage in a concentration-dependent manner. Protection of cells by these drugs was not affected by pretreatment with indomethacin (10−5 mol/L) for 4 h. Removal of Na− , but not Ca2+ , from the acidified medium totally abolished the inhibitory effect of EGF, but not that of sucralfate. Genistein (a tyrosine kinase inhibitor) apparently reduced the inhibitory effect of EGF. DNA synthesis by RGM1 cells did not increase when cells were incubated with EGF for 4 h. We conclude that both EGF and sucralfate protect RGM1 cells from acid- and pepsin-induced damage and that the mechanism of protection by EGF against acid-induced damage seems to be via activation of Na+ /H+ exchangers. 相似文献
76.
Percutaneous transcatheter occlusion of coronary artery fistulas using detachable balloons 总被引:1,自引:0,他引:1
Three pediatric patients underwent successful transcatheter coronary artery fistula occlusion using the Debrun system. This
latex balloon system offers several advantages over other occlusion systems. First, the balloon delivery and release is controlled.
Second, “test occlusions” can be performed that allow simultaneous balloon inflation, coronary cineangiography, and electrocardiographic
monitoring. Third, because the balloons are flow-directed, they are easily positioned in properly chosen locations. Finally,
the balloons can be constructed to suit the size of the fistula. In this study, two patients received only one balloon; in
the other patient two balloons were placed in the same fistula. All fistulas drained into either the right atrium or ventricle
and were successfully occluded. After a follow-up period of up to 3 years, no local or systemic reactions to the balloons
were recognized. We conclude that detachable balloon occlusion of coronary artery fistulas is a safe, effective alternative
to surgical ligation in selected pediatric patients. 相似文献
77.
小柴胡汤口服液药效作用的研究 总被引:2,自引:0,他引:2
观察了小柴胡汤口服液的主要药理作用。研究表明,小柴胡汤口服液有显著抑制角叉菜胶诱发的大鼠踝关节水肿(p<0.05),保护四氯化碳所致的大鼠急性肝功能损害,有极显著降低血清SGPT及LDH的作用(P<0.01)。对家兔发热反应也有较好的抑制作用。此外,小柴胡汤口服液对小鼠兔疫反应也有一定的增强作用,可促进小鼠碳粒廓清速率,提高血清溶血素水平及增强鸡红细胞所致的迟发性过敏反应。 相似文献
78.
化疗对淋巴瘤伴乙肝病毒感染患者肝功能影响的回顾性分析 总被引:1,自引:0,他引:1
目的研究化疗对淋巴瘤伴乙肝病毒感染患者肝功能的影响。方法回顾性病例分析,比较50例HBsAg(-)、20例HBsAg(+)和18例小三阳的恶性淋巴瘤患者化疗后肝功能变化情况。结果HBsAg(-)组、HBsAg(+)组和小三阳组化疗后Ⅲ级以上肝功能损害分别是0%、15%、55%。结论伴乙肝病毒感染的淋巴瘤患者化疗后肝功能损害明显,尤其小三阳患者损害更为严重,甚至死亡。 相似文献
79.
溶栓治疗和神经保护治疗是缺血性脑卒中的两大药物干预策略,其中广义的神经保护治疗包括神经保护和神经修复两种方法,而目前存在的中西医结合缺血性脑卒中的药物干预策略可能也存在多层次、分阶段干预的特点,体现了祖国医学"同病异治"的原则,我们认为现有的缺血脑保护方法主要针对缺血性脑卒中的不同发展阶段,而神经修复的研究,尤其是中医药促进神经干细胞再生的研究,可能蕴涵着巨大的发展潜力和无限商机. 相似文献
80.
Yu. B. Lishmanov L. N. Maslov N. V. Naryzhnaya 《Bulletin of experimental biology and medicine》1997,123(3):239-241
Immobilization induces stress damage to the heart. DAGO, an agonist of μ-opiate receptors potentiates, while an agonist of
peripheral μ-opiate receptors prevents this damage. Naltrexone reduces, while methylnaltrexone, an inhibitor of peripheral
μ-opiate receptors, potentiates the stress-induced damage to the heart. Other opiate ligands have no effect on heart damage.
It is suggested that the stress-induced damage to the heart is promoted by activation of central μ-opiate receptors and prevented
by stimulation of peripheral μ-opiate receptors.
Translated fromByulleten'Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 276–278, March, 1997 相似文献