查询词典 acid-base

Study on the Crystallization Process of Labeled GL-7-ACA Acylase CA130 Complex 7β-bromoacetyl amino cephalosporanic acid (BA-7-ACA), an analog of glutaryl-7-amino cephalosporanic acid (GL-7-ACA), can inhibit and specifically alkylate GL-7-ACA acylase (CA130) from Pseudomonas sp. 130, forming a carbon-carbon bond between BA-7-ACA and the C-2 on indole ring of Trp-β4 residue of CA130.Here we reported that BA-7-ACA labeled CA130 (BA-C130) could self-catalyze the hydrolysis of BA-7-ACA during crystallization process. The hydrolysis was confirmed to be a reaction analogous to the one of GL-7-ACA by comparative MALDI-TOF (matrix-assisted laser desorption/ionization-time of flight) spectrometry analysis.

二、GL-7-AcA酰化酶CA130标记复合物的结晶过程研究溴乙酰氨基头孢烷酸（7β-bromoacetyl amino cephalosporanic acid，BA-7-ACA）作为戊二酰-7-氨基头孢烷酸（GL-7-ACA）的类似物，不仅能够抑制GL-7-ACA酰化酶CA130的活力，而且能通过在BA-7-ACA和CA130的β亚基第四位色氨酸吲哚环二位碳原子之间形成碳-碳共价键而将CA130特异的烷基化。

DNA refers to deoxyribonucleic the acid deoxyribonucleic acid (chromosome and gene constituent) the deaeration nucleotide high polymer, is the chromosome principal constituent.

DNA 指deoxyribonucleic acid 脱氧核糖核酸(染色体和基因的组成部分)脱氧核苷酸的高聚物，是染色体的主要成分。

To study the applicable prospect of suicide gene on tumor therapy in clinic,we cloned the gene of D-amino acid oxidase and the gene of yeast cytosine deaminase.We hope to establish the transgenic mices of DAAO gene and YCD gene,and the two transgenic strain mices are valuable animal system for studying the biological characteristic of DAAO gene and YCD gene ,for studing the killing activity of DAAO/D-Ala and YCD/5-FC gene therapy systems on tumor.The D-amino acid oxidase gene derived from R.gracilis and it could oxidize D-amino acids. Hydrogen peroxide(H2O2) is a reactive oxygen species generated in the deamination of D-Ala catalyzed by DAAO.

为了探讨自杀基因在临床肿瘤治疗中的应用前景，建立自杀基因肿瘤治疗评价的动物模型，我们克隆了D-氨基酸氧化酶(D-amino acid oxidase，DAAO)基因和酵母菌胞嘧啶脱氨酶(yeast cytosine deaminase，YCD)基因，希望建立DAAO基因及YCD基因转基因小鼠，为研究DAAO及YCD基因的生物学特性、开发和评价DAAO／D-Ala及YCD／5-FC自杀基因系统进行肿瘤治疗建立良好的实验动物模型。

So people who need an effective but milder nonprescription medication for the relief of excess stomach acid should choose Acid-Ease.

所以需要有效但较温和的非处方药来消除过多胃酸的人应该选择Acid-Ease。

Gamma-aminobutyric acid, a four-carbon nonprotein amino acid, serves as a major inhibitory neurotransmitter in mammalian nervous systems. GABA has several physiological functions such as hypotensive activity, treatment of epilepsy, tranquilizing and allaying excitement, enhancing memory, controlling asthma, regulating hormone secretion, promoting reproduction and activating liver and kidney function.

氨基丁酸(γ-aminobutyric acid，简称为GABA)是一种天然存在的非蛋白质氨基酸，为哺乳动物中枢神经系统中重要的抑制性神经递质，具有降血压、治疗癫痫、镇静安神、增强记忆、控制哮喘、调节激素分泌、促进生殖、活化肝肾等多种生理功能，其制备和应用广受人们的关注与重视。

In this study, we determined that the antimutagenic properties of various tea extracts including green, oolong, pu-erh tea, and black tea and six polyphenols include rutin, quercetin, apigenin, gallic acid, umbelliferone, and tannic acid were examined by Ames test which is a widely applied short-term bacterial assay for detecting DNA damage effect of mutagen.

在本篇研究中，我们探讨利用Ames test的方法筛检不同品种茶类包括绿茶、乌龙茶、普洱茶、红茶和数种常见的多酚类化合物包括单宁酸tannic acid、gallic acid、rutin、umbelliferone、apigenin、quercetin对於抑制PhIP（2-amino-1-methyl-6-phenylimidazo(4，5-b)pyridine）和 2-AAF（2-Acetylaminofluorene）两种致突变剂的抗突变作用。

But both 20 years and 2 years old of pu-erh tea extracts show a strong inhibitory effects against 2-AAF. In addition, tannic acid, gallic acid, rutin, umbelliferone, and quercetin exhibited stronger antimutagenicities against PhIP than apigenin; while all of these polyphenols displayed inhibitory effect against 2-AAF.

而比较数种多酚类化合物发现，tannic acid、gallic acid、rutin、umbelliferone和quercetin对於抑制PhIP的抗突变作用比apigenin来的有效，但是apigenin和其他多酚类化合物对於抑制2-AAF的抗突变作用则均具有明显的抑制效果。

The effects and mechanism of GABAergic neurons, NOergic neurons, opioid peptide and cyclic adenosine monophosphate in the nucleus reticularis thalami on sleep-wakefulness cycle of rats and the effects and mechanism of the 5-HTergic nerve fibers project from the nucleus raphes dorsalis to RT on sleep-wakefulness cycle of rats were investigated with the methods of brain stereotaxic, nucleus spile, microinjection and polysomngraphy.1. The effects of GABAergic neurons in RT on sleep-wakefulness cycle of rats1.1 Microinjection of 3-mercaptopropionic acid (3-MP, a kind of glutamate decarboxylase inhibitor) into RT. On the day of microinjection, sleep only decreased a litter. On the second day, sleep marked decreased and wakefulness marked increased. On the third and fourth day, sleep and wakefulness stages resumed to normal.1.2 Microinjection of gamma-amino butyric acid (GABA 1.0μg) into RT enhanced sleep and reduced wakefulness compared with control; while microinjection of L-glutamate (L-Glu, 0.2μg) decreased sleep and increased wakefulness; microinjection of bicuculline (BIC, 1.0μg), a GABAA receptor antagonist, enhanced wakefulness and reduced sleep; microinjection of baclofen (BAC, 1.0μg), GABAB receptor agonist, had the same effects as GABA.2. The effects of NOergic neurons in RT on sleep-wakefulness cycle of rats2.1 Microinjection of L-arginine (L-Arg, 0.5μg) into RT decreased sleep compared with control, but there were on statistaical difference between L-Arg group and control; while microinjection of sodium nitroprusside (SNP, 0.2μg), a NO donor into RT, sleep marked decreased and wakefulness marked increased. Microinjection of nitric oxide synthase inhibitor, N-nitro-L-arginine (L-NNA, 2.0μg) into RT enhanced sleep and reduced wakefulness.2.2 After simultaneous microinjection of L-NNA (2.0μg) and SNP (0.2μg) into RT, SNP abolished the sleep-promoting effect of L-NNA compared with L-NNA group; after simultaneous microinjection of L-NNA (2.0μg) and L-Arg(0.5μg) into RT, we found that L-NNA could not blocked the wakefulness-promoting effect of L-Arg.3. The effects of opioid peptide in RT on sleep-wakefulness cycle of rats3.1 Microinjection of morphine sulfate (MOR, 1.0μg) into RT increased wakefulness and decreased sleep compared with control; while microinjection of naloxone hydrochloride (NAL, 1.0μg), the antagonist of opiate receptors, into RT, enhanced sleep and reduced wakefulness.3.2 After simultaneous microinjection of MOR (1.0μg) and NAL (1.0μg) into RT, the wakefulness-promoting effect of MOR and the sleep-promoting effect of NAL were not observed compared with control.4. The effects of cAMP in RT on sleep-wakefulness cycle of rats Microinjection of cAMP (1.0μg) into RT increased sleep and decreased wakefulness compared with control; microinjection of methylene blue (MB,1.0μg) into RT enhanced sleep and reduced wakefulness compared with control.5. The effects of the 5-HTergic nerve fibers project from DRN to RT on sleep-wakefulness cycle of rats5.1 When L-Glu (0.2μg) was microinjected into DRN and normal sodium (NS,1.0μg) was microinjected into bilateral RT. We found that sleep was decreased and wakefulness was increased compared with control; when L-Glu (0.2μg) was microinjected into DRN and methysergide (MS,1.0μg), a non-selective 5-HT antagonist, was microinjected into bilateral RT, We found that sleep was enhanced and wakefulness was reduced compared with L-Glu group.5.2 When p-chlorophenylalanine (PCPA, 10μg) was microinjected into DRN and NS (1.0μg) was microinjected into bilateral RT, We found that sleep was increased and wakefulness was decreased compared with control; microinjection of 5-hydroxytryptaphan (5-HTP, 1.0μg), which can convert to 5-HT by the enzyme tryptophane hydroxylase and enhance 5-HT into bilateral RT, could block the effect of microinjection of PCPA into DRN on sleep-wakefulness cycle.

本研究采用脑立体定位、核团插管、微量注射、多导睡眠描记等方法，研究丘脑网状核(nucleus reticularis thalami，RT)中γ-氨基丁酸(gamma-amino butyric acid ，GABA)能神经元、一氧化氮(nitrogen monoxidum，NO)能神经元、阿片肽类神经递质、环一磷酸腺苷(cyclic adenosine monophosphate，cAMP)及中缝背核(nucleus raphes dorsalis，DRN)至RT的5-羟色胺(5-hydroxytryptamine，5-HT)能神经纤维投射对大鼠睡眠-觉醒周期的影响及其作用机制。1 RT内GABA能神经元对大鼠睡眠-觉醒周期的影响1.1大鼠RT内微量注射GABA合成关键酶抑制剂3-巯基丙酸(3-MP，5μg)，注射当天睡眠时间略有减少，第二日睡眠时间显著减少，觉醒时间明显增多，第三、四日睡眠和觉醒时间逐渐恢复至正常。1.2大鼠RT内微量注射GABA受体激动剂GABA( 1.0μg)后，与生理盐水组比较，睡眠时间增加，觉醒时间减少；而RT内微量注射L-谷氨酸(glutamic acid， L-Glu， 0.2μg)后，睡眠时间减少，觉醒时间增加；RT内微量注射GABAA受体阻断剂荷包牡丹碱(bicuculline，BIC，1.0μg)后，睡眠时间减少，觉醒时间增加；RT内微量注射GABAB受体激动剂氯苯氨丁酸(baclofen，BAC，1.0μg)后，产生了与GABA相似的促睡眠效果。2 RT内NO能神经元对大鼠睡眠-觉醒周期的影响2.1大鼠RT内微量注射NO的前体L-精氨酸(L-Arg，0.5μg)后，与生理盐水组对比，睡眠时间略有减少，但无显著性意义；而RT内微量注射NO的供体硝普钠(Sodium Nitroprusside，SNP，0.2μg)后可明显增加觉醒时间，缩短睡眠时间；微量注射一氧化氮合酶抑制剂L-硝基精氨酸(L-arginine，L-NNA，2.0μg)后，引起睡眠时间增多，觉醒时间减少。2.2大鼠RT内同时微量注射L-NNA(2.0μg)和SNP(0.2μg)后与L-NNA组比较发现SNP逆转了L-NNA的促睡眠作用；RT内同时微量注射L-NNA(2.0μg)和L-Arg(0.5μg)后，与L-NNA(2.0μg)组比较发现L-Arg可以增加觉醒而缩短睡眠，其促觉醒作用未能被NOS的抑制剂L-NNA所逆转。3 RT内阿片肽对大鼠睡眠-觉醒周期的影响3.1大鼠RT内微量注射硫酸吗啡(morphine sulfate，MOR，1.0μg)后与生理盐水组对比，睡眠时间减少而觉醒时间增加； RT内微量注射阿片肽受体拮抗剂盐酸纳洛酮(naloxone hydrochloride，NAL，1.0μg)后与生理盐水组比较，睡眠时间增加而觉醒时间减少。3.2大鼠RT内同时微量注射MOR(1.0μg)和NAL(1.0μg)后，与生理盐水组对比，原有的MOR促觉醒效果和NAL的促睡眠效果都没有表现。4 RT内环一磷酸腺苷信使对大鼠睡眠-觉醒周期的影响大鼠RT内微量注射cAMP(1.0μg)后与NS(1.0μg)组比较，睡眠时间增多而觉醒时间减少；RT内微量注射亚甲蓝(methylene blue，MB，1.0μg)后，与NS组比较，睡眠时间增多而觉醒时间减少。5中缝背核投射到丘脑网状核的5-羟色胺能神经纤维对大鼠睡眠-觉醒周期的影响5.1大鼠DRN内微量注射L-Glu(0.2μg)，同时在双侧RT内微量注射NS (1.0μg)后，与对照组(DRN和双侧RT注射NS， 0.2μg)比较，睡眠时间减少，觉醒时间增多；大鼠DRN内微量注射L-Glu(0.2μg)，同时在双侧RT内微量注射二甲基麦角新碱(methysergide， MS， 1.0μg )后，与对照组(DRN注射L-Glu 0.2μg，双侧RT注射NS 1.0μg)比较，睡眠时间增多，觉醒时间减少。5.2大鼠DRN内微量注射对氯苯丙氨酸(p-chlorophenylalanine，PCPA，10μg)，同时在双侧RT内微量注射NS (1.0μg)后，与对照组(DRN和双侧RT注射NS， 1.0μg)比较，睡眠时间增多，觉醒时间减少；大鼠DRN内微量注射PCPA(10μg)，产生睡眠增多效应后，在双侧RT内微量注射5-羟色胺酸(5-hydroxytryptaphan ， 5-HTP， 1.0μg )后，与对照组(DRN注射PCPA 10μg，双侧RT注射NS 1.0μg)比较，睡眠时间减少，觉醒时间增多。

The aim of this study, we try to simplify the EA recovery process from strawberry pomaces and evaluate the safety of products, ellagic acid concentrate, and ellagic acid standard by AMES test and L5178Y TK assay.

本研究目的为简化回收鞣花酸浓缩物之流程，并以安氏试验法及L5178Y TK分析法来评估鞣花酸标准品(Ellagic acid standard， EAS)，及鞣花酸浓缩物(Ellagic acid concentrate， EAC)的安全性。

Test Preparation Transfer about 2 g of the substance under test, accurately weighed, to a glass-stoppered, 250-mL conical flask, add 20 mL of a mixture of equal volumes of nitric acid and sulfuric acid, attach a suitable condenser, reflux the mixture for 1 hour, cool, cautiously dilute with water, and boil until fumes of nitrous acid no longer are noticeable.

Test准备 Transfer大约2 g在测试之下的物质，准确地被称，对玻璃防止， 250ml conical烧瓶，增加硝酸的相等的容量混合物的20 mL，并且硫酸，附有一适当的 condenser，循环加热混合物1个小时，凉快，慎重地稀释与直到亚硝酸发烟的水和煮沸 acid不再是引人注目的。

Fancy gold-plated dangling earrings with facetted White Opal crystals.

花式镀金悬垂耳环与facetted白欧泊水晶。

This essay chooses the study aim from biology teachers in middle school in Shi Jiazhuang which tells us that most of the middle school biology teachers in Shi Jiazhuang have the"burnout", lower successfulness, individualize.

本文选取石家庄市初中生物教师作为研究对象，运用问卷调查的方法对石家庄市初中生物教师职业倦怠的现状进行调查，调查结果发现，石家庄市初中生物教师这一群体普遍存在职业倦怠，情感枯竭程度偏高，成就感偏低，去个性化程度最为严重。