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61.
本文研究了竹红菌甲素(简称甲素)对S-180肿瘤细胞膜的作用。结果表明,甲素结合光照可引起S-180肿瘤细胞膜蛋白质交联、脂质过氧化产物MDA含量增加。但在SDS-PAGE分析中观察到的高分子蛋白质交联带并非由MDA所引起。甲素同样可引起小牛胸腺组蛋白光氧化、发生分子交联,并可敏化色氨酸、酪氨酸和组氨酸的无氧化。  相似文献   
62.
1 A 'retrospective' of the development of the drug treatment of hypertension is presented from the early days of ganglion blockers to the present time together with a review of the evidence of benefit from treatment.
2 Current issues and debates are summarised including shortfalls in the control of hypertension in populations, difficulties surrounding the measurement of blood pressure, disagreement on the levels of blood pressure to treat, the goal blood pressures to aim at, issues surrounding lifestyle measures such as the low salt diet and low intensity exercise, and treatment with diuretics and with calcium antagonists.
3 A 'perspective' is presented on some avenues for progress in the years ahead. These will include the identification of genetic markers to determine the hypertensive individuals with the greatest risk of death and of cardiovascular complications.  相似文献   
63.
Tissue removal by infrared lasers is accompanied by thermal damage to nonablated tissue. The extent of thermal damage can be controlled by a choice of laser wavelength, irradiance, and exposure duration. The effect of exposure duration has been studied in vivo by using CO2 lasers with pulse widths that vary from 2 microseconds to 50 msec. Pulse widths of 50 msec, typical of a shuttered, continuous-wave CO2 laser, produce damage regions 750 micron wide in normal guinea pig skin; the use of a 2-microseconds-long pulse reduced this damage zone to as little as 50 micron. Using 2-microseconds-long pulses, in vitro studies showed that the minimum zone of thermal damage varied significantly with tissue type. The thermal denaturation of these tissues has been studied and correlated with damage. The effect of denaturation temperature and pulse duration on the width of the damage zone is explained by a simple model.  相似文献   
64.
Summary: IgAN is the commonest primary glomerulonephritis in all parts of the world; the different incidence reported in different geographical areas is mainly due to different biopsy policies, even though genetic factors, still unclarified, may be acting. Progression to ESRF occurs in IgAN at a variable rate (average renal survival at 10 years is 80–87%), and many studies, reviewed in this paper, have sought to identify clinical and histological features which are predictive of the outcome. A functional impairment at presentation and a severe proteinuria are the most powerful clinical indicators of unfavourable prognosis, while both glomerular and interstitial sclerosis are the most reliable histological indicators. The fact that these prognostic indicators are not always reliable in predicting the outcome for a single patient, probably due to the pathophysiology of the progressive damage in this disease, is stressed.  相似文献   
65.
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   
66.
 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   
67.
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   
68.
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   
69.
小柴胡汤口服液药效作用的研究   总被引:2,自引:0,他引:2  
杨军  陈澍禾 《中成药》1992,14(6):26-28
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   
70.
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   
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