海南青牛胆中游离氨基酸的分析

对海南青牛胆(Tinospora hainanesis H.S.Lo et Z.X.Li)藤茎中游离氨基酸进行了测定。结果表明,海南青牛胆中游离氨基酸种类极其丰富,其含量总游离氨基酸为0．27％,人体必需氨基酸占总游离氨基酸选75％,精氨酸含量最高,为0．0909％。     

不同品种药用菊花中游离糖类及游离氨基酸含量的HPLC分析

为比较不同品种菊花的品质特征,本文采用HPLC法测定其游离糖类及游离氨基酸的含量.结果表明,不同品种菊花中游离糖类主要成分是果糖和葡萄糖,蔗糖和麦芽糖未检出,总游离糖类含量约为9.07～18.76g/1O0g,其中黄山贡菊中含量最高,为18.76g/100g,黄菊中最低,为9.07g/100g;其总游离氨基酸含量约为0.563～2.806g/100g,七月菊中含量最高,为2.806g/100g,杭白菊中最低,为0.563g/100g.     

烟草叶片游离氨基酸含量的分析

分析结果表明,烟草叶片中含有１６种以上游离氨基酸,其中谷氨酸含量最高。不同层次叶片的总游离氨基酸含量不同,从脚叶（下层）至顶叶（上层）总游离氨基酸的含量逐渐增加。此外,烟草叶片中尚含有芳香族氨基酸,其中苯丙氨酸与酪氨酸对烟叶色、香、味的形成起着重要作用。     

厌氧消化消化残留液中游离氨基酸含量的测定

采用ＧＣ－９Ａ气相色谱仪进行三种不同原料厌氧消化残留液中游离氨基酸珠测定。实验结果表明,鸡粪厌氧消化残留液中游离氨基酸种类最多,且含量较其他两种残留液高,鸡粪残留液更适于再利用。     

鱼腥草游离氨基酸组成及含量的HPLC分析

研究不同鱼腥草材料间及其两个不同采收时期游离氨基酸组成及含量差异 ,筛选游离氨基酸种类较多 ,含量较高的新品系 ,并确定适宜的采收时期。对 1 9份鱼腥草材料阴干地上部分游离氨基酸成分进行了高效液相色谱分析。 6月和 1 0月采收的鱼腥草中分别含有 1 5种和 1 4种氨基酸 ,都不含Cysteine -ss -Cysteine和Lysine,1 0月采收的还不含有Tyrosine。氨基酸中Proline含量最高 ,Glycine含量最低。此外 ,1 0月采收的鱼腥草的游离氨基酸总量高于 6月采收的鱼腥草。供试材料中 6月采收的W0 1 - 86和 1 0月采收的W0 1 - 5多数游离氨基酸含量均为同一采收时期的最高值。分别为 5 894 .76mg/kg和 6 1 6 6 .1 3mg/kg。此外 ,蕺菜与峨眉蕺菜间游离氨基酸成分间无显著差别。因此鱼腥草不同材料间及不同采收时期游离氨基酸含量不尽相同 ,游离氨基酸含量与染色体数目间相关不显著     

Na2CO3胁迫对星星草幼苗游离氨基酸含量的影响

对Ｎａ２ＣＯ３胁迫下星星草幼苗游离氨基酸含量的研究结果表明,星星草幼苗游离氨基酸总含量随盐浓度的增加而增加。各组分中Ａｌａ、Ｃｙｓ、Ｇｌｙ、ｌｅｕ、Ｍｅｔ、Ｐｒｏ、Ｐｈｅ、Ｖａｌ的含量随着Ｎａ２ＣＯ３浓度的增加而增加,其中Ａｌａ、Ｃｙｓ、Ｇｌｙ、ｌｅｕ、Ｍｅｔ、Ｐｒｏ与Ｎａ２ＣＯ３浓度呈极显正相关关系。Ｎａ２ＣＯ３胁迫下星星草幼苗体内氨累积,同时Ａｓｐ－ＮＨ２的含量明显增加,有效降低氨对幼苗的毒     

女性生殖道感染细菌种类分布及耐药性分析

目的：探讨女性生殖道病原菌种类及其对抗菌药物的耐药状况。方法：对1999年1月至2001年12月女性生殖道分泌物标本普通培养分离的病原菌及耐药性作回顾性分析。结果：677份患者样本共分离出病原菌491株,其中G^-菌占29.12%,G^ 菌占48.72%,真菌占22.61%,主要以白色念珠菌,表皮葡萄球菌,大肠埃希菌和金黄色葡萄球菌为主,占检出菌的57.64%。分离到的病原菌绝大多数对其临床应用的抗生素均具有较高的耐药性。结论：女性生殖道感染菌种类多,耐药性严重,临床应重视病原学检查,根据药敏结果合理使用抗菌药物。     

实验动物血及组织游离氨基酸含量

本文报告实验动物血及组织游离氨基酸含量,结果表明,实验狗和Wistar大鼠血游离氨基酸含量比较恒定。实验兔组织游离氨基酸含量普遍高于血。     

Effects of maturation and co-culture treatments on the developmental capacity of early bovine embryos.

A total of 901 cumulus-oocyte complexes (COCs) were collected from bovine ovaries obtained at a local abattoir. COCs randomly assigned to Treatment I (n = 451), were cultured in TCM-199 + 10% fetal bovine serum (FBS) and hormones, while oocytes in Treatment II (n = 450) were cultured in TCM-199 + 20% estrous cow serum (ECS). Assessment of maturation revealed that 91.3% (42/46) of oocytes in Treatment I had reached metaphase II of meiosis, which was greater (P less than 0.05) than the 73.3% (33/45) in Treatment II. Following in vitro fertilization, 203 oocytes from Treatment I were co-cultured on bovine granulosa cells (Treatment IA) while the remaining 202 oocytes were co-cultured on bovine oviductal cells (Treatment IB). Similarly, 203 oocytes from Treatment II were co-cultured on granulosa cells (Treatment IIA) or oviductal cells (Treatment IIB, n = 202). Co-culture was maintained for 8 days. The proportion of cleaved zygotes was higher (P less than 0.05) in Treatment IB (86.6%) compared to Treatments IA (78.8%), IIA (58.1%), and IIB (64.8%). The proportion of cleaved zygotes that progressed beyond the 16-cell stage was also greater (P less than 0.001) in Treatment IB (71.4%) compared to Treatments IA (50.0%), IIA (35.4%) and IIB (55.8%). Treatment IB also produced the highest proportion of blastocysts (P less than 0.0001) (41.1%) versus 24.6% (IA), 11.3% (IIA) and 18.3% (IIB). The proportion of day 6 morulae that progressed to form day 8 blastocysts was similar for both co-culture treatments (IA, 70.1%; IB 70.2%; IIA, 51.5%; IIB 50.8%) and varied only between in vitro maturation groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cd2+急性胁迫下方格星虫体腔液消化酶活力和游离氨基酸的变化

为了解Cd2+急性胁迫下方格星虫体腔液消化酶活力和游离氨基酸的变化规律, 采用毒理学试验方法, 在确定Cd2+对方格星虫毒性强度的基础上, 选取48h最低致死浓度为试验浓度, 研究该浓度Cd2+胁迫下方格星虫体腔液消化酶活力和游离氨基酸的动态变化。结果表明: 方格星虫死亡率随着Cd2+浓度的升高而增加,Cd2+对方格星虫的24h和48h的LC50分别为37.80和22.68 mg/L。在48h最小致死浓度下, Cd2+对方格星虫体腔液蛋白酶和淀粉酶活力在试验周期内均表现为抑制, 且淀粉酶活力受到的抑制作用较强; Cd2+胁迫前期脂肪酶活力显著升高(P0.05), 24h后又显著降低(P0.05), 48h时仅为初始水平的40%, 说明低浓度Cd2+对脂肪酶活力有诱导作用, 高浓度Cd2+则产生抑制。方格星虫体腔液游离氨基酸的组成和含量在Cd2+胁迫48h内均有显著变化(P0.05)。各游离氨基酸含量及氨基酸总量在24h前均无显著变化(P0.05), 24h后先上升后下降(P0.05),36h的游离氨基酸总量达到初始水平的2倍以上, 为145.50 mg/100 mL, 大部分游离氨基酸组成百分比也在24h前较稳定, 24h后呈现峰值变化。总之, Cd2+急性胁迫对方格星虫体腔液消化酶活力和游离氨基酸均有显著影响(P0.05), 且消化酶活力与游离氨基酸含量和组成的变化与胁迫时间有关。     

Hysteresis and Statistical Errors in Free Energy Perturbation L to D Amino Acid Conversion

Abstract

A theory based on a Langevin equation along the reaction coordinate is developed to explain and calculate systematic and statistical errors in free energy perturbation simulations. The errors are calculated exactly when both the perturbation potential and the mean potential from the surrounding degrees of freedom are harmonic in the reaction coordinate. The effect of the mean potential is small as long as the force constant is small compared to the force constant of the perturbation potential. This indicates that the results obtained with zero mean force may still be valid as long as the second derivate of the mean potential is small compared to that of the perturbation potential. The theory is applied to conversion between L and D amino acids by changing the position of the minimum of the harmonic improper dihedral potential between ±35.264 degrees. For phenylalanine bound in the active site of a protein (thermolysin) we find from 20 psec. simulations statistical errors and hysteresis that both are about 2.5 kJ/mol in agreement with what is obtained from the theoretical predictions. The statistical errors are proportional to the square root of the coupling to the heat bath and inversely proportional to the square root of integration time while the (positive) hysteresis due to that the reaction coordinate lags behind is linear in the same quantities. This shows that the systematic errors will dominate in short simulations while the statistical ones will dominate for long simulations. The treatment is based on that the systematic influence of the surroundings can be represented by a mean force upon the reaction coordinate. If the relaxation processes of the environment are slow this may not be true. Then additional errors have to be considered.     

Energetics of peptide bond formation at elevated temperatures

Summary The free energies of formation of the peptide bond between carbobenzoxy-glycine and L-phenylalanine amide in aqueous solution at temperatures up to 60°C were calculated from experimentally determined equilibrium constants. The reaction was catalyzed by a thermophylic enzyme. The thermodynamic energy barrier to peptide bond formation was found to decrease with increasing temperature: the standard free energy of peptide bond formation did appear to become negative in the region of 60°C. The possible significance of these results for peptide bond formation under prebiotic conditions is discussed.     

Changes in Amino Acids and Nitric Oxide Concentration in Cerebrospinal Fluid During Labor Pain

This study analyzes the relationship between amino acids and pain perception during active labor. Cerebrospinal fluid (CSF) levels of the excitatory amino acids (EAAs)—glutamate, aspartate and their amide forms, inhibitory amino acids (IAAs)—glycine, γ-amino butyric acid (GABA) and taurine and nitric oxide (NO) related compounds—arginine and citrulline (by-product of NO synthesis) were compared between pregnant women at term pregnancy with labor pain (n = 38) and without labor pain (Caesarian section; n = 30). The levels of aspartate, glycine, GABA and citrulline were significantly higher; whilst taurine was significantly lower in the labor pain group. These findings suggest that aspartate and NO are associated with labor pain. An inhibitory role for the IAA taurine and a pronociceptive role for glycine in labor pain are proposed.     

脑疾病与游离氨基酸的研究

脑疾病包括肝性脑病 (或肝昏迷 ) ,乙型脑炎 ,儿童智力发育不全 ,脑瘫 ,新生儿缺氧缺血脑病以及脑衰老等。研究结果说明 :( 1 )肝性脑病 (或肝昏迷 )和乙型脑炎患者体液中谷氨酰胺水平升高 ,这种升高可以作为以上两种疾病的早期诊断 ;( 2 )脑瘫 ,智力发育不全以及脑衰老 (动物 )等患者 ,体液中谷氨酸浓度降低而r 氨基酸 (GABA)浓度升高 ,它们可以作为评价大脑损伤程度的指标 ,同时也有早期诊断这些疾病的价值 ;( 3)适当补充必需氨基酸能控制以上各种脑疾病的发展。     

水稻籽粒游离氨基酸含量及其产量的种子和母体遗传效应分析

本文利用朱军等提出的禾谷类作物种子数量性状平均数遗传模型,探讨了水稻籽粒游离氨基酸含量及其产量的遗传效应．结果表明：籽粒游离氨基酸含量、游离氨基酸产量除受控于种子直接加性效应外,还受母体植株加性效应和显性效应的作用,且母体效应比种子直接加性效应更重要,其中尤以母体显性效应最重要．2个性状种子直接遗传率和母体遗传率均达显著或极显著水平,狭义遗传率均较高,基因累加选择的同时不能忽视杂种优势利用．游离氨基酸含量与游离氨基酸产量细胞质效应、母体显性效应间存在极显著相关性．     

莫西沙星联合用药方案对耐多药肺结核患者血清游离氨基酸和免疫功能的影响

目的:探讨莫西沙星联合用药方案对耐多药肺结核(MDR-TB)患者血清游离氨基酸和免疫功能的影响。方法:选取2015年9月到2018年1月期间我院收治的90例MDR-TB患者,根据乱数表法将患者分为研究组(n=45)、对照组(n=45),其中对照组给予左氧氟沙星联合常规化疗治疗,研究组则给予莫西沙星联合常规化疗治疗,比较两组临床疗效、痰菌转阴率、病灶吸收率、空洞闭合率、血清游离氨基酸和免疫功能,记录两组治疗期间不良反应情况。结果:研究组治疗18个月后的临床总有效率为71.11%(32/45),高于对照组的46.67%(21/45)(P0.05)。研究组治疗18个月后痰菌转阴率、病灶吸收率、空洞闭合率均较对照组高(P0.05)。两组患者治疗18个月后CD4+、免疫球蛋白A(Ig A)、免疫球蛋白G(Ig G)均升高,CD8+降低(P0.05),研究组治疗18个月后CD4+、Ig A、Ig G高于对照组,而CD8+低于对照组(P0.05)。两组治疗18个月后缬氨酸、谷氨酸均升高,且研究组高于对照组(P0.05)。两组患者总不良反应发生率比较无明显差异(P0.05)。结论:莫西沙星联合常规化疗治疗MDR-TB的疗效确切,可有效改善患者血清游离氨基酸水平,提高机体免疫功能,同时不增加不良反应发生率。