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101.
Effects of N-acetylcysteine on arginase, ornithine and nitric oxide in renal ischemia-reperfusion injury. 总被引:1,自引:0,他引:1
BACKGROUND: Renal ischemia-reperfusion (I/R) is a complex syndrome involving several mechanisms such as renal vasoconstrictions, extensive tubular damage and glomerular injury. N-Acetylcysteine (NAC), a potent antioxidant by itself, may serve as a precursor for glutathione synthesis. The aim of this study was to investigate the possible effects of NAC on liver and kidney tissue arginase activity, ornithine and plasma nitric oxide levels during the I/R injury of kidney. METHODS: Twenty-four female Sprague-Dawley rats divided into three groups: group 1; was given saline intraperitoneally (i.p.). Saline to group 2 and NAC (300 mg kg(-1)) to group 3 were injected i.p. 30 min before induction of ischemia. Groups 2 and 3; subjected to bilateral renal ischemia (60 min) followed by reperfusion (24 h). After the reperfusion period, the rats were sacrificed and liver and kidney tissue arginase activities, ornithine and plasma nitric oxide (NO) levels were determined. RESULTS: NAC had an increasing effect on both of liver and kidney tissue arginase activities and ornithine levels while decreasing plasma NO concentration. CONCLUSION: The stimulatory effect of NAC on arginase activity may result in an inhibition of the plasma NO level. Moreover, it could be possible that one of the protective mechanisms of NAC might be through the stimulation on the both liver and kidney tissue ornithine levels. 相似文献
102.
Disorders of the lipoprotein metabolism are an important cause of premature coronary artery disease and myocardial infarction. Of the genetic lipoprotein disorders, elevation of apoprotein (apo) B containing lipoproteins is the most frequent one in the western population. We aimed to define the prevalence of genetic lipoprotein disorders and other risk factors in a population from a country with a low average cholesterol levels. We examined 48 consecutive patients with premature myocardial infarction below age 55, their 78 siblings and age and body mass index matched controls for familial lipoprotein disorders. The patients with premature myocardial infarction had higher triglyceride, low-density lipoprotein, apo B, lipoprotein (Lp) (a) and lower apo A1 levels then controls (p<0.05). Of the nonlipid risk factors, 67% smoked, 8% had diabetes mellitus, 17% had hypertension and 58% a family history of premature coronary artery disease. Fifty percent of these patients with premature myocardial infarction had a familial lipoprotein disorder. Familial excess of Lp(a) was the most frequent lipoprotein abnormality present in 16% of the patients followed by familial combined hyperlipidemia. We conclude that, Lp(a) increase was the most frequent familial lipoprotein abnormality in this population. The frequency of familial lipoprotein disorders in this population emphasises the need to screen siblings of patients with premature myocardial infarction. 相似文献
103.
Nurettin Heybeli Faik Nuzhet Oktar Sibel Ozyazgan Gokhan Akkan Serhat Ozsoy 《Technology and health care》2003,11(3):207-216
Treatment of osteomyelitis with local antibiotic delivery systems has become a common practice in orthopaedic surgery. This study attempted to show that locally produced pure or bioglass reinforced plaster of Paris, hydroxyapatite and sodium alginate are promising biomaterials and mainly because of economical reasons and availability, may be an alternative in clinical practice, especially for developing countries. A total of 32 rabbits were divided into four groups (n:8). In group A, sodium alginate + cephazoline; in group B, plaster of Paris + bioglass + cephazoline; in group C, plaster of Paris + hydroxyapatite + cephazoline and in group D, plaster of Paris + cephazoline were used. The blood serum cephazoline concentrations were analyzed by high performance liquid chromatography on days 1 to 10 everyday and then at days 13, 17, 18, 24, 25 and 30. The mean values +/- standard deviations and median values of blood serum antibiotic concentrations for groups A, B, C and D were 1.45 +/- 0.40 (1.42) mcg/ml, 1.53 +/- 0.64 (1.31) mcg/ml, 1.92 +/- 0.39 mcg/ml (1.90) and 1.41 +/- 0.65 (1.25) mcg/ml, respectively. The detected antibiotic level was constantly over the minimum inhibitory concentration for Staphylococcus aureus. In conclusion, it can be stated that these materials are promising as a antibiotic delivery system even with simple production methods. 相似文献
104.
The present study evaluates potential toxic effects of bis(2-ethylhexyl) adipate (DEHA) plasticizer to larval (72 h post fertilization) zebrafish (Danio rerio) by analyzing changes in expression levels of stress-related genes (p53, rad51 and xrcc5) and assessing possible DNA damage of DEHA in larvae. The lethal concentration for 50% mortality (LC50) in larval zebrafish exposed for 96 h to 0–200 mg L?1 DEHA was 89.9?±?8.03 mg L?1. A concentration-dependent increase in DNA strand breaks was detected in cells from larvae exposed for 96 h to DEHA. There were some significant differences in induction of stress-related genes in larvae exposed to DEHA relative to control. 相似文献
105.
目的:研究《金匮要略》中治疗水气病的用药规律,为临床治疗水气病选方和用药提供参考。方法:收集并筛选《中华医典》中治疗水气病的方剂,应用中医传承辅助平台(V2.5)软件,采用频数分析、关联规则Apriori算法、改进的互信息法等数据挖掘方法对药物配伍规律进行挖掘。结果:共筛选治疗水气病处方101首,涉及107味中药,其中使用频次最高的三位药物为甘草、茯苓、桂枝;选择相关度为7、惩罚度为2,应用复杂系统熵聚类的层次聚类分析演化出3-4味药的核心组合12个,新处方6首。结论:《金匮要略》中治疗水气病以宣肺发汗,健脾利水,温阳散寒为主,反映了“发汗利水、温阳健脾”的祛邪与扶正兼顾之治则治法。 相似文献
106.
107.
Nurettin Onur Kutlu Nasuhi Engin Aydin Mehmet Aslan Taner Bulut Ünsal Özgen 《Pediatric hematology and oncology》2013,30(2):141-146
Calciphylaxis is a poorly understood and highly morbid syndrome of vascular calcification and skin necrosis. Hypercalcemia, hyperphosphatemia, and secondary hyperparathyroidism are the factors implicated in the pathogenesis of calciphylaxis, which is generally identified in patients with hyperparathyroidism secondary to end-stage renal disease. It has also been observed in primary hyperparathyroidism, end-stage liver disease, and rheumatoid arthritis, in the absence of renal disease. There are few case reports of calciphylaxis occurring in hypercalcemia of malignancy. An unusual case is reported of calciphylaxis associated with malignant melanoma of the soft parts in the absence of renal or parathyroid disease. This is the first reported case of this soft tissue sarcoma showing calciphylactic changes. 相似文献
108.
Ali Kagan Gokakin Atilla Kurt Gunduz Akgol Boran Cihat Karakus Mustafa Atabey Ayhan Koyuncu Omer Topcu Erdal Goren 《Arab Journal Of Gastroenterology》2012,13(4):180-183
Background and study aimsThe diagnostic methods such as upper gastrointestinal endoscopy (UGE) have played an important role in the evaluation of peptic ulcer (PU). Every year, millions of Muslims fast in Ramadan month. The aim of this study was to evaluate the effect of fasting on PU via UGE.Patients and methodsA total of 321 patients in the period from 2009 to 2011, who underwent UGE as a diagnostic work-up mainly for epigastric pain, were analysed. Patients were divided into three groups: Patients who have been evaluated by UGE, in the month just before Ramadan (group I, n = 69), in Ramadan month (group II, n = 132) and in the month just after Ramadan (group III, n = 120).Continuous data were expressed as the mean ± SD, and were compared with one-way analysis of variance (ANOVA) test amongst groups. Categorical data were given as percentages and were compared with the chi-squared test.ResultsEpigastric pain was the most common indication for referral in each group. Interestingly, the indication ‘bleeding’ was found to be the least in group II, but was far from statistical significance. The highest prevalence of duodenal ulcers and duodenitis was found in group II; the differences to the other groups were statistically significant.ConclusionDuodenal ulcers and duodenitis were found more during Ramadan month. We recommend that, the patients with epigastric pain may fast by taking their medications. 相似文献
109.
Haldun O. Kamburo?lu Omer F. Boran Mustafa F. Sargon Abdullah Ke?ik 《International journal of shoulder surgery》2008,2(3):62-63
An unusual anatomic variation of the deltoid muscle was found in a 45-year-old female cadaver during dissection of the right upper extremity. The posterior fibers of the right deltoid muscle were enclosed in a distinct fascial sheet and the deltoid muscle was seen to arise from the middle 1/3 of the medial border of the scapula. There was no accompanying vascular or neural anomaly of the deltoid muscle. To the best of our knowledge, unilateral posterior separation of the deltoid muscle with a distinct fascia has not been described previously. While dissecting deltoid, posterior deltoid, or scapular flaps, the surgeon needs to look out for this variation because it may cause confusion. 相似文献
110.
A new natural adsorbent material, Bathurst burr powder, was used to remove crystal violet dye from synthetic wastewaters. Particle size distribution and SEM and FTIR analyses were performed to characterize it. The effect of the operational adsorption process parameters (pH, ionic strength, initial dye concentration, adsorbent dose, contact time, temperature) onto the adsorption process was evaluated in a batch system. Equilibrium, kinetic, and thermodynamic studies were performed in order to understand the adsorption process. Taguchi method and ANOVA test were used to optimize the dye adsorption conditions and to establish the percentage contribution of each factor, respectively. The accuracy of the Taguchi prediction method was analyzed by correlating the predicted dye removal efficiency with the experimentally determined one. The particle size distribution analysis showed that 82.15% of the adsorbent particles have an average size below 0.5 mm. The adsorption process followed the Langmuir isotherm and pseudo-second order kinetic model. Maximum adsorption capacity value (164.10 mg·g−1) was higher compared to many similar adsorbents. The process was endothermic, spontaneous, and favorably involving a physisorption mechanism. The Taguchi method showed that the most influential controllable factor was pH (65% contribution in adsorption efficiency) and the data analysis indicates a very good accuracy of the experimental design (R2 = 0.994). The obtained results demonstrated that Bathurst burr powder can be used as a cheap and efficient adsorbent for crystal violet dye removal from aqueous solution. 相似文献