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41.
Objective:To investigate whether ketamine could inhibit lipopolysaccharide (LPS)-induced intracellular calcium elevation and NF-kappa B activation in monocytes. Materials and methods:Isolated rat monocytes were challenged with 10 g/ml LPS with or without the presence of various concentrations of ketamine (10, 100, 1000 M). Intracellular calcium was monitored by laser confocal microscopy. NF-kappa B activity of the nuclear extracts of monocytes was analyzed by electrophoretic mobility shift assay (EMSA). Results:LPS provoked a significant calcium elevation and enhanced NF-kappa B activity in monocytes. Ketamine above concentration of 100 M inhibited endotoxin-induced intracellular calcium elevation and NF-kappa B activity. Ketamine itself had no effect on either of them. Conclusions:These findings suggest that ketamine could suppress NF-kappa B in monocytes exposed to endotoxin, and this anti-inflammatory effect might act through attenuating intracellular calcium elevation.Received 31 October 2003; returned for revision 18 December 2003; accepted by I. Ahnfelt-Rønne 26 Januaryy 2004  相似文献   
42.
本文研究了不同浓度的Zn对培养的乳鼠心肌细胞自发性搏动及心肌细胞动作电位的影响。实验结果表明,加Zn在0.125—2ppm范围内,自发性搏动群落的出现率增高,与对照组比较,P<0.001。但Zn的浓度超过一定范围(4 ppm),自发搏动率则呈降低趋势;8 ppm组明显低于对照组,P<0.01.Zn对心肌细胞动作电位的影响表现为动作电位的发放频率减慢,波幅降低,波宽变窄和最大除极速度减慢。  相似文献   
43.
44.
Periodized carbohydrate availability can enhance exercise capacity, but the effects of short-term fat adaptation carbohydrate restoration (FACR) diets on metabolic responses and exercise performance in endurance athletes have not been conclusively determined. This study aimed to investigate the effect of a FACR diet on measures of resting metabolism, exercise metabolism, and exercise performance. Well-trained male runners (n = 8) completed a FACR dietary intervention (five days’ carbohydrate < 20% and fat > 60% energy, plus one-day carbohydrate ≥ 70% energy), and a control high-carbohydrate (HCHO) diet for six days (carbohydrate > 60% energy; fat < 20% energy) in a randomized crossover design. Pre- and post-intervention metabolic measures included resting metabolic rate (RMR), respiratory quotient (RQ), maximum fat oxidation rate during exercise (MFO), and maximum fat oxidation intensity (FATmax). Measures of exercise performance included maximal oxygen uptake (VO2max), running economy (RE), and 5 km running time trial (5 km-TT). In FACR compared with HCHO, there were significant improvements in FATmax (p = 0.006) and RE (p = 0.048). There were no significant differences (p > 0.05) between FACR and HCHO in RMR, RQ, VO2max, or 5 km-TT. Findings suggest that a short-term (six days) FACR diet may facilitate increased fat oxidation and submaximal exercise economy but does not improve 5 km-TT performance.  相似文献   
45.
Histocompatibility is crucial in effecting survivalof allografts.Due to differences in histocompatibilitybetween donor and recipient,rejection would happento some extent after transplantation. Therefore,theevaluation of differences in histocompatibility betweendonor and recipient would be contributive to selectionof donor and judgement on prognosis oftransplantation. HLA typing and mixed lymphocyticreaction (MLR) are the classical methods to evaluatethe histocompatibility between donor and r…  相似文献   
46.
BackgroudCoenzyme Q10 (CoQ10) is involved in the biosynthesis of adenosine triphosphate (ATP), and is most abundant in the mitochondrial membrane. The primary CoQ10 deficiency caused by COQ2 defect is mostly manifested as encephalopathy, encephalopathy with nephropathy, and rarely as an isolated nephrotic syndrome.MethodsClinical and pathological data and peripheral blood samples of 2 siblings with steroid-resistant nephrotic syndrome (SRNS) and their family members of a Chinese pedigree were collected. DNA was extracted and subjected to next-generation sequencing of target genes of hereditary nephropathy.ResultsCompound heterozygous mutations of COQ2 (c.1058A > G, p.Y353C, paternal and c.973A > G, p.T325A, maternal)were identified in both siblings of the pedigree. Mutation of p.Y353C was novel. The proband was a girl, who presented with SRNS at the age of 7 months. CoQ10 was administered after the gene sequencing results came out. Proteinuria decreased gradually to 1+, occasionally negative. The child was normal in growth and intelligence. She is now 4 years old. The second patient was her elder brother. He was found to have SRNS at the age of 2 years old. Renal pathology indicated focal segmental glomerulosclerosis (FSGS). Electronic microcopy revealed that a large quantity of mitochondria with normal contour was accumulated within the podocytes. Both patients were in normal intelligence without convulsion.ConclusionThe 2 cases harboring COQ2compound heterozygous mutations presented with isolated SRNS, with a renal pathology of FSGS and a large quantity of mitochondria with normal contour accumulated within the podocytes. CoQ10 was efficacy in eliminating proteinuria.  相似文献   
47.
BackgroundPyriform sinus fistula (PSF) is a rare congenital anomaly, and the preferred definitive treatment is yet to be verified. In this study, we investigated the treatment outcomes of PSF specifically comparing endoscopic-assisted surgery and endoscopic radiofrequency ablation (RA).MethodsThe medical records of patients treated for PSF at the Shanghai Children's Hospital between October 2016 and September 2019 were retrospectively evaluated.ResultsThere were 93 girls and 98 boys. The median age at onset and operation was 3 years and 5 years, respectively. Endoscopic-assisted surgery was performed in 143 patients. During the same period, RA was performed in 48 patients, and 10 of them concurrently underwent incision and drainage of neck abscesses. Longer hospital stay was found in the endoscopic-assisted surgery group than in the RA group (10.50 ± 3.93 vs. 5.02 ± 3.30 days, P < 0.001). Postoperative complications were not significantly different between the two groups, except for neck infection (0 vs. 8.3%, P = 0.004). After a median follow-up period of 21 months, no significant difference was found between the two groups in terms of recurrence (1.4% vs. 0, P = 0.560).ConclusionPatients treated with RA had a significantly shorter hospital stay than those treated with endoscopic-assisted surgery. Outcomes of endoscopic-assisted surgery and RA were not significantly different for the management of PSF and treatment method should be tailored to the patient.Level of evidenceIV.  相似文献   
48.

Bauxite residues are a mass of industrial wastes derived from aluminum metallurgy. This work provided a simple pyrolysis method to magnetize the bauxite residue to serve as a magnetic adsorbent towards heavy metals removal. The X-ray diffraction patterns and Mossbauer spectrum results confirmed the partial reduction of iron species with an obvious enhancement in magnetization. The magnetized bauxite residue exhibited excellent removal efficiencies for Cu2+, Cd2+ and Pb2+ with maximum adsorption capacities of 219.0 mg g?1, 275.4 mg g?1, and 100.4 mg g?1, which could be quickly separated through a magnet. The adsorption equilibrium data were fitted to the Langmuir isotherm model, while the adsorption kinetics followed a pseudo-first-order model. According to the characterization results, chemical precipitation and sorption was the major mechanism for the removal of Cu2+, Pb2+, and Cd2+. Thus, the magnetized bauxite residue exhibited promising applications for heavy metals removal in wastewater.

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49.
目的 探讨三黄胶囊的解热、通便,抗菌作用。方法 采用大鼠酵母性发热法,体外细菌培养法和小鼠肠道碳末推进实验。结果 三黄胶囊对大鼠酵母性发热有解热作用,对金黄色葡萄球菌、链球菌和痢疾杆菌有较强的抑制作用,具有明显的泻下和促进胃肠蠕动的作用。结论 三黄胶囊具有解热、抑菌及通便作用。  相似文献   
50.
目的 :探讨不育男性精浆转铁蛋白 (Tf)含量与精子顶体完整性的关系。方法 :149例不育男性患者按精子密度≥ 2 0× 10 6 / ml和 <2 0× 10 6 / ml分正常精子密度组和少精子组 ,同时进行精浆 Tf和精子顶体完整率 (PIA)分析。结果 :不育男性少精子组精浆 Tf含量显著低于正常精子密度组 (P<0 .0 1) ;正常精子密度的不育男性精子 PIA<80 %组精浆 Tf含量显著低于精子 PIA≥ 80 %组 (P<0 .0 1)。结论 :正常精子密度的不育男性精子 PIA下降与精浆 Tf水平有密切的关系  相似文献   
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