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11.
不育男性精浆总抗氧化能力与精子运动功能的关系 总被引:4,自引:1,他引:3
目的:研究不育男性精浆总抗氧化能力(TAC)与精子运动能力和方式之间的关系,探讨精浆TAC水平在男性生育中的临床意义。方法:113例精子密度正常的不育男性,28例正常生育男性作为对照组。精液于37℃液化后采用计算机辅助精液分析(CASA)系统进行精液常规分析,采用比色法进行精浆TAC分析。结果:正常生育组精浆TAC为(19.82±6.33)U,不育男性精子密度正常组精浆TAC为(14.37±8.45)U,不育男性精子密度正常组与正常生育组比较存在显著性差异(P<0.01)。精浆TAC与a级精子百分率(r=0.208,P<0.05)和(a+b)级精子百分率(r=0.231,P<0.05)呈显著正相关,精浆TAC与精子运动参数中的前向性(r=0.200,P<0.05)、直线性(r=0.208,P<0.05)、曲线速度(r=0.189,P<0.05)、直线速度(r=0.210,P<0.05)、平均移动速度(r=0.215,P<0.05)及鞭打频率(r=-0.248,P<0.01)之间有显著的相关性,其中前向性、直线性、直线速度、曲线速度、平均移动速度与TAC呈正相关(P<0.05),而鞭打频率与TAC呈负相关(P<0.01)。精浆TAC与摆动性、侧摆幅度、平均移动角度之间无显著相关。结论:精浆中TAC水平与精子运动能力和运动方式密切相关,适宜的精浆TAC为精子运动提供了良好的外部环境,精浆中过低的TAC水平与精子运动能力下降和运动方式改变有关,可能是引起男性不育的病因之一。精浆中TAC分析可为探讨男性不育的发病机制以及临床用药提供依据。 相似文献
12.
[目的]研究超敏C反应蛋白(hs-CRP)、总抗氧化状态(TAS)联合血脂检测在早老性痴呆症诊断中的应用价值:[方法]选择浦东新区精神卫生中心早老性痴呆专科门诊患者54例,作超敏C反应蛋白、总抗氧化状态与血脂检测。[结果]与对照组比较,实验组hs-CRP、TAS差异非常显著,t1=4.55,t2=2.79,P1〈0.001,P2〈0.01;血脂中甘油三酯、低密度脂蛋白胆固醇、载脂蛋白B、Lp(a)差异显著;t1=3.01,P1〈0.01,t2=2.21,P2〈0.05,t3=2.64,P3〈0.01,t4=1.91,P4〈0.05。[结论]超敏C反应蛋白、总抗氧化状态联合血脂(甘油三酯、低密度脂蛋白胆固醇、载脂蛋白B、Lp(a))检测对实验室诊断早老性痴呆症具有较好敏感性和特异性,临床应用前景乐观。 相似文献
13.
Ken Hui 《Early child development and care》2006,176(3):411-419
In 1993, Rauscher et al. reported a temporary increase in spatial-temporal ability after listening to Mozart's music. This led to numerous replication and extension studies with mixed findings in the past decade. This study investigated the 'Mozart effect' in preschool children. Forty-one boys and girls, aged three to five, attempted a series of pencil-and-paper maze tests after each of three listening conditions: Mozart's Piano Concerto in A Major (K488), age-appropriate popular music and silence. Overall, there were no statistically significant differences among the three interventions. The results are discussed in relation to the findings of other investigations of the Mozart effect, and the need for further investigation of possible trends. 相似文献
14.
Abstract – The type of liquid medium used to store avulsed teeth prior to replantation has been shown to affect the long‐term prognosis. One possibility is that some storage media contain hydrogen peroxide (H2O2) that may be toxic to periodontal ligament cells. Therefore, the aim of this study was to determine if the addition of catalase to storage media improved the prognosis of replanted dog teeth. Forty‐eight mongrel premolar roots were endodontically treated, extracted, randomly divided and placed into one of four storage media: Hank's balanced salt solution (HBSS), containing no antioxidant); Viaspan, containing the antioxidant, glutathione, or the same two media supplemented with catalase(100 U ml?1) for 1, 5, or 26 h prior to replantation. After 2 months, the dogs were euthanized and the roots histologically examined to evaluate the attachment tissues. Regardless of the storage medium used, overall healing was excellent and only 4% of the roots displayed inflammatory or replacement resorption. When roots from the different storage media were compared, those stored in HBSS were found to display the highest incidence of surface resorption (55.7%). Supplementation of HBSS with catalase resulted in a lower level of surface resorption (48.6%) that was statistically significant (P < 0.05). Roots stored in Viaspan – or + catalase displayed even lower levels of surface resorption (41.3 and 38.2%, respectively). The improvement observed with catalase‐supplemented HBSS was confined to the 45‐min incubation period; only Viaspan – or + catalase reduced surface resorption at the 5‐ and 26‐h incubations. Collectively, these data demonstrate that roots stored in media containing antioxidant activity undergo less surface resorption. These results suggest that low levels of H2O2 in storage media for avulsed teeth may adversely affect periodontal ligament cells. 相似文献
15.
海王碱性保健饮料是以海带为主要原料的制品。本文通过大鼠游泳耐力和耐缺氧试验证明,海王碱性保健饮料有明显地抗疲劳、抗缺氧作用(P<0.01)。同时我们分析测试了饮料中营养素成分及其含量,本品富含碘、钙、铁、β—胡萝卜素和人体所必需的多种营养素及微量元素。 相似文献
16.
心理因素对小学生脑力工作能力影响的研究 总被引:4,自引:2,他引:2
采用横断面研究方法,对180名小学三年级学生脑力工作能力与其智力、性格、学习动机等心理因素和学习、睡眠时间等作息因素的关系进行分析研究。验证了学习、睡眠时间是影响学生脑力工作能力重要的外部因素;脑力工作能力与智力和学习成绩呈正相关。学生自身的心理因素中,学习动机对脑力工作能力有重要影响,所以激发和强化学生的学习动机,是保持和提高学生学习工作能力的有效手段;而性格内外向性、情绪稳定性等因素,对脑力工作能力的影响不明显。 相似文献
17.
社会能力评定量表的编制及信效度检验 总被引:4,自引:1,他引:3
目的:编制社会能力评定量表并检测其信度和效度。方法:在全国五大行政区用社会能力评定量表评估1605例正常人(男性814名,女性791名),分析量表的信效度。结果:全量表的Cronbach's α系数为0.88-0.92,三个分量表的d系数为0.81~0.88;量表的分半信度为0.76~0.87,量表的重测信度为0.67~0.86,量表评分者信度为0.91~0.97,表明量表具有较好的内部一致性和稳定性;各条目与总分的相关系数0.49-0.80,分量表与总分的相关系数为0.76~0.89,通过因子分析,证实了量表的结构效度;全量表总分和职业能力得分与被试单位提供的实际社会能力评分呈高度相关,与韦氏智商呈中低度相关。结论:量表编制符合心理测量学要求,具有良好的信度和效度。 相似文献
18.
Boumerfeg S Baghiani A Messaoudi D Khennouf S Arrar L 《Phytotherapy research : PTR》2009,23(2):283-288
This study was conducted to search for xanthine oxidase (XO) inhibitors from the root extracts of Tamus communis L. traditionally used in folk medicine in Algeria. Root extracts with different solvents were screened for purified milk xanthine oxidase inhibition. The root extracts (methanol, chloroform and ethyl acetate) and proteins, obtained in distilled water, inhibited bovine, sheep and human milk XO from three species in a concentration-dependent manner, with an additional superoxide scavenging capacity, which reached its highest level with ethyl acetate extract (IC(50) = 0.15, 0.04 and 0.09 g/L) for bovine XO, sheep XO and human XO, respectively. The antioxidant potential was confirmed with the non-enzymatic method, total radical-trapping antioxidant parameter (TRAP) assay, which showed that the Tamus communis L. extracts have a potential antioxidant activity in the same order obtained by using the reduction of cytochrome c, an enzymatic method, in which the antioxidant activity followed a decreasing order: ethyl acetate extract > chloroform extract > protein. 相似文献
19.
Geneive E. Henry Matthew S. Campbell Ashlee A. Zelinsky Yunbao Liu Camile S. Bowen‐Forbes Liya Li Muraleedharan G. Nair David C. Rowley Navindra P. Seeram 《Phytotherapy research : PTR》2009,23(12):1759-1762
Three acylphloroglucinol derivatives have been isolated from the hexane and acetone extracts of the aerial parts of Hypericum densiflorum Pursch. The compounds were characterized by NMR spectroscopy and mass spectrometry and identified as 4‐geranyloxy‐2,6‐dihydroxybenzophenone (1), 4‐geranyloxy‐1‐(2‐methylpropanoyl)‐ phloroglucinol (2) and 4‐geranyloxy‐1‐(2‐methylbutanoyl)‐phloroglucinol (3). Compounds 1–3 were evaluated for in vitro cell proliferation inhibitory activity against human breast (MCF‐7), lung (NCI H460), CNS (SF‐268), stomach (AGS) and colon (HCT‐116) tumor cell lines; antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA); inhibition of cyclooxygenase (COX‐1 and ‐2) enzymes; and antioxidant activity in the lipid peroxidation (LPO) assay. All three compounds showed moderate to strong antitumor, antibacterial, antioxidant and inhibition of COX‐2 activities. Also, this is the first reported occurrence of compound 3 in the Hypericum genus. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献