茶梗、茶枝屑代料对黑木耳生长及品质的影响

对比分析黑木耳在茶梗、茶枝屑不同基质配方上的菌丝生长、出菇表现、产量及营养成分。结果表明:黑木耳在各基质配方上均能正常生长、出菇,除配方CG1(78.5%茶梗)、CZ1(78.5%茶枝屑)产量及生物学效率低于对照CK(78.5%杂木屑)外,其他均高于CK,其中配方CZ2(48.5%茶枝屑)最高,生物学效率比CK高出10.09%;含茶枝屑配方栽出的黑木耳粗蛋白、粗脂肪、粗纤维、Ca、Fe、Zn、总氨基酸、必需氨基酸等营养成分均高于CK,而含茶梗配方栽出的黑木耳则是粗蛋白、粗多糖、灰分高于CK。综上所述,茶梗、茶枝屑作为代料栽培黑木耳可行,茶枝屑代料栽培出的黑木耳总体品质要优于茶梗代料。     

谈缓冲溶液pH值计算公式的教学

根据酸碱质子理论,将弱酸及弱酸盐和弱碱及弱碱盐组成的两种不同类型的缓冲溶液pH值的计算公式统一起来了,这样更便于教学。     

Urinary Organic Acids Quantitated in a Healthy North Indian Pediatric Population

Human urine gives evidence of the metabolism in the body and contains numerous organic acids and other compounds at a variety of concentration. The concentration of organic acids in urine varies from population to population due to genotype, food habits and other epigenetic and environmental influences. Knowledge of the reference values for urinary organic acids in a healthy pediatric population is very important for critical evaluation. This study was designed to quantify 16 organic acids in a healthy north Indian pediatric population. Early morning urine samples from healthy pediatric subjects of age 1 day to 16 years who did not have symptoms of any disease were analyzed for organic acid content. The children were not on any supplemental vitamins or drugs and were on a free and unrestricted diet. The creatinine concentration of each sample was determined before organic acid analysis. Organic acids were extracted from urine with ethyl acetate, extracted residue was air dried, converted into trimethylsilyl derivatives and analysed by gas chromatography mass spectrometry. Here we reported the age wise mean values and standard deviations for each compound, adjusted for creatinine content (mmol/mol of creatinine). We found the concentration of most of the metabolites are higher in our population in comparison to other populations. Such data may help to provide a basis for diagnosing metabolic abnormalities in patients in a specific ethnicity.     

射箭运动员在不同训练时期血液氨基酸变化的研究

目的：观察射箭运动员在不同运动负荷状态时的血液氨基酸的变化。方法：用高效液相法测定射箭运动员冬训期间不同的训练时期血液中四种氨基酸——门冬氨酸（Asp）、谷氨酸（Glu）、甘氨酸（（Gly）和r-氨基丁酸（GABA）的含量。结果：在进行中等强度训练期和大强度训练期运动后1h血浆中谷氨酸的血浆浓度明显升高（P〈0．01）。而在大强度训练期后明显下降,甚至低于安静值;门冬氨酸在中等强度训练后血浆浓度也升高（P〈0．05）,在疲劳期则呈下降趋势,但仍高于安静值;在进行中等强度训练期和大强度训练期运动1h后血浆中r-氨基丁酸、甘氨酸均上升。大强度训练期明显升高,与训练前期安静值相比有显著意义（P〈0．01）。结论：射箭运动员在长时间大强度大运动量训练后,血液中的氨基酸会发生变化,中枢疲劳可能从血浆氨基酸的变化反映出来。     

Effect of citrulline on post-exercise rating of perceived exertion,muscle soreness,and blood lactate levels: A systematic review and meta-analysis

BackgroundCitrulline is one of the non-essential amino acids that is thought to improve exercise performance and reduce post-exercise muscle soreness. We conducted a systematic review and meta-analysis to determine the effect of citrulline supplements on the post-exercise rating of perceived exertion (RPE), muscle soreness, and blood lactate levels.MethodsA random effects model was used to calculate the effect sizes due to the high variability in the study design and study populations of the articles included. A systematic search of PubMed, Web of Science, and ClinicalTrials.gov was performed. Eligibility for study inclusion was limited to studies that were randomized controlled trials involving healthy individuals and that investigated the acute effect of citrulline supplements on RPE, muscle soreness, and blood lactate levels. The supplementation time frame was limited to 2 h before exercise. The types and number of participants, types of exercise tests performed, supplementation protocols for L-citrulline or citrulline malate, and primary (RPE and muscle soreness) and secondary (blood lactate level) study outcomes were extracted from the identified studies.ResultsThe analysis included 13 eligible articles including a total of 206 participants. The most frequent dosage used in the studies was 8 g of citrulline malate. Citrulline supplementation significantly reduced RPE (n = 7, p = 0.03) and muscle soreness 24-h and 48-h after post-exercise (n = 7, p = 0.04; n = 6, p = 0.25, respectively). However, citrulline supplementation did not significantly reduce muscle soreness 72-h post-exercise (n = 4, p = 0.62) or lower blood lactate levels (n = 8, p = 0.17).ConclusionCitrulline supplements significantly reduced post-exercise RPE and muscle soreness without affecting blood lactate levels.     

生物大分子溶液结构的NMR测定法

随着高分辨核磁共振（ＮＭＲ）仪和多维ＮＭＲ技术的快速发展,近年来高场ＮＭＲ仪已成为测定生物大分子在溶液中的三维结构的最强有力的手段。目前已有１７００多个生物大分子的溶液结构用高分辨ＮＭＲ技术进行了测定。该文简要综述了这一高新技术的特点、测定流程,并分析了若干实例。     

补服氨基酸对人体有氧耐力的影响

文章主要采用文献资料法和实验法,将忻州师院体育系6名健康男性作为受试者,旨在观察运动前补服支链氨基酸对人体有氧耐力的影响,进而得出对补服氨基酸对人体有氧耐力的影响。     

口服支链氨基酸对小鼠耐力的影响

实验组小鼠每天额外供给支链氨基酸２５ｍｇ，对照组每天额外供给葡萄２５ｍｇ。４天后发现，运动后试验组和对照组血清乳酸水平分别为２．７５ｍｍｏＬ／Ｌ和３．８９ｍｍｏＬ／Ｌ，差异非常显著，Ｐ＜０．０１。力竭运动试验游泳时间延长，乳酸水平下降，表明支链氨基酸可增强实验动物的运动能力，延缓运动性疲劳的出现。     

Influence of the microbiota on epigenetics in colorectal cancer

Colorectal cancer is one of the most common malignancies and is the second leading cause of cancer death worldwide. Generally, there are three categories of colorectal cancer development mechanism—genetic, epigenetic and aberrant immunological signaling pathways—all of which may be initiated by an imbalanced gut microbiota. Epigenetic modifications enable host cells to change gene expression without modifying the gene sequence. The microbiota can interact with the host genome dynamically through the interface presented by epigenetic modifications. In particular, bacterially derived short-chain fatty acids have been identified as one clear link in the interaction of the microbiota with host epigenetic pathways. This review discusses recent findings relating to the cross talk between the microbiota and epigenetic modifications in colorectal cancer.     

运动结合饮食干预对肥胖青少年血清脂肪酸组分和身体成分的影响及其相关性研究

目的：探索4周运动结合饮食干预对肥胖青少年的血清脂肪酸组分和身体成分的影响,同时分析脂肪酸基础值与身体成分相关指标变化量的相关性。方法：以2017年暑期参加皓千体育发展有限公司全封闭减肥训练营的25名肥胖青少年为研究对象（平均年龄：15.96±1.88y;平均BMI：32.66±4.51 kg/m²）,进行为期4周的联合运动结合饮食干预,干预前后测试并分析身体成分、身体形态和血清脂肪酸组分的变化及其相互关系。结果：4周后,受试者的体重、身体质量指数（BMI）、体脂量、脂肪质量指数（FMI）、四肢脂肪量、腰围、臀围和腰臀比均显著降低,瘦体重%显著增加（P<0.001）;血清饱和脂肪酸（SFA）中,总饱和脂肪酸（SFAs）、肉豆蔻酸（C14：0）、十五烷酸（C15：0）、棕榈酸硬（C16：0）、脂酸（C18：0）、花生酸（C20：0）、山萮酸（C22：0）、二十三烷酸（C23：0）和二十四烷酸（C24：0）含量均显著降低（P<0.05）;单不饱和脂肪酸（MUFA）中,总单不饱和脂肪酸（MUFAs）、棕榈油酸（C16：1 n-7）、油酸（C18：1 n-9）和鳕油酸（C20：1 n-9）含量显著降低（P<0.01）;多不饱和脂肪酸（PUFA）中,总多不饱和脂肪酸（PUFAs）、总n-6多不饱和脂肪酸（n-6 PUFA）、亚油酸（C18：2 n-6）、二十碳二烯酸（C20：2 n-6）、双高-γ-亚麻酸（C20：3 n-6,DGLA）、花生四烯酸（C20：4 n-6,ARA）和α-亚麻酸（C18：3 n-3）显著下降（P<0.05）;Pearson相关性分析及一元线性回归分析表明,干预前血清C14：0与C20：3 n-6的基础值与体脂%及瘦体重%的变化量正相关,C16：1 n-7的基础值与体脂量、上肢脂肪量、右下肢脂肪量的变化量正相关（P<0.05）。结论：4周运动和饮食干预能明显改善肥胖患者身体成分、身体形态及血清脂肪酸组分;血清C14：0、C16：1 n-7、C20：3 n-6的基础值与身体成分的变化量存在线性关系,可以为减肥夏令营的饮食优化及减肥效果的预测提供参考。