Authors are thankful to K. P. Madhu, Nita Beliappa and staff of the Media Centre of Indian Institute of Science Education and Research, Pune for their help in the video production. The work was supported by funding under the Centre of Excellence program of Department of Biotechnology, Government of India to SG and postdoctoral fellowship by Department of Science and Technology, Government of India to RK.

在饲养响应1.水润文化与测量<ol><li>通过每天用卤虫喂养它们并保持它们在培养基（1毫摩尔Tris-HCl缓冲液，pH值7.6，1 mM氯化钠，1mM的氯化钙 ，0.1mM的氯化钾，和0.1mM 硫酸镁 ）包含在保持在培养水螅息肉玻璃碗，在18℃下进行12小时光照，12小时黑暗周期如前所述12。 </li><li>用于测量馈响应，传送一个成熟的具有5-6个触须到24孔板的单个孔水螅息肉。通过倾斜地取出从井的残余介质中，然后立即加入500μl的新鲜培养基。 </li><li>准备在九头蛇媒体9微米的谷胱甘肽的解决方案。由于谷胱甘肽溶液是容易氧化，通常使用为每个实验新鲜制备的谷胱甘肽溶液。 </li><li>板转移到具有用于图像记录规定一个显微镜的成像平台。使用深色背景，这样的行为Ò˚F水螅水螅可以清晰成像对对比背景。 </li><li>房间用于观察和成像水螅自由的行为与波动强度，气流和噪音的灯。这些干扰也可导致水螅息肉显示触手收缩 - 甚至在没有谷胱甘肽。 </li><li>让息肉5分钟放松。 </li><li>确保息肉位于沿井，使得行为可以清楚地拍摄的中心区域。如果息肉是在井的边缘，使之在中心通过使用移液管冲洗介质，并再次使其放松。 </li><li>捕捉在松弛状态下九头蛇的图像。这将是零时间点的观察。 </li><li>快速添加9微米谷胱甘肽溶液以达到在该井的3μM的终浓度。根据实验和响应由水螅示的目的，测试一系列不同浓度的谷胱甘肽和噗的瑟所需的适当的浓度。 </li><li>添加谷胱甘肽的解决方案，采集图像每隔15-30秒4-5分钟后后，立即启动定时器。时间推移成像过程中不要改变倍率设置。 </li><li>添加谷胱甘肽的溶液轻轻地和均匀的流动，使得在井的动物的位置将被最低限度地干扰在视显微镜的领域。然而，如果息肉添加谷胱甘肽溶液后广泛移动时，移动板轻轻地使息肉中的视图用于图像捕获的字段。 </li><li>在对照实验中，使用的介质缺乏谷胱甘肽，同时保持所有其他参数相同。 </li><li>要确保在第一天的一半执行所有上述实验步骤: - :00之前，以避免昼夜节律对馈送响应的程度的可能影响。 </li><li>打开每个使用GNU图像处理程序（GIMP）拍摄的图像中。 </l我&gt; <li>使用"测量"工具，可从菜单&gt;工具&gt;测量来确定每个触角和hypostome的顶端末端之间的距离。如果嘴开口中的任何图像的观察，确定了开口的中心与所述触手的尖端之间的距离。请参考这个距离作为触手蔓延。 </li><li>之前，谷胱甘肽曝光后计算平均价差触须每个息肉。计算的平均触手蔓延在零时间点，以该比率在每个随后的时间点。这个比例将被称为相对触手蔓延。 </li><li>重复测量，至少20息肉。 </li></ol><img alt="式（1）" fo:content-width="3.5in" src="/files/ftp_upload/52178/52178eq1.jpg" width="400" /> <img alt="式（2）" fo:content-width="4in" src="/files/ftp_upload/52178/52178eq2.jpg" width="450" /> 2.方法验证使用饥饿型号<ol><li>对于饥饿，转移几水螅珊瑚虫为一个单独的玻璃碗里，不要喂它们5天。每日与卤虫饲料的几个息肉，对照组以同样大小的碗。改变介质从每日两实验的碗，以避免在培养基中的真菌生长。 </li><li>在实验当天，喂水螅的对照组与卤虫1小时，并从培养基中除去所有未吃掉的和死的卤虫后使用这些水螅用于后续实验。 </li><li>衡量饥饿水润与对照组按上面的步骤1.描述，以避免任何偏见的方法九头蛇比较饲养的反应，由于观测时间，每次交替的饥饿的测量和控制水螅珊瑚虫。 </li></ol>

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The authors declare no competing financial interests.

在水螅摄食行为代表了最原始的化学感受系统的后生动物之一。虽然谷胱甘肽（GSH）后刺丝囊辅助捕获猎物释放的甲壳类流体存在检测前不久1，无论是GSHR蛋白质也不是假定的编码基因/ S进行了表征，从九头蛇是最新的。一些尝试已经进行了表征谷胱甘肽结合蛋白在水螅8，14，15，但是，这些推测的受体蛋白质的身份仍不清楚并且很少有其他分子组分，它有可能向馈送反应中，已经报道了16日，17，唯一的特征GSHR在动物王国中是金鱼18。经典的技术，如使用G蛋白偶联受体的信号级联的各种蛋白的抑制剂，以及先进的分子生物学技术（RNA干扰介导的基因沉默和CRISPR-Cas9介导的基因组编辑），可提供战俘强大的工具，用于识别GSH的分子成分的水润信号级联。该受体的这种改变的表达和功能，谷胱甘肽信令的其它组分的刻痕的读出将被改变摄食行为。因此，有必要设计一种方法，用于测量引起的GSH在水螅饲养响应。 表型上，馈送反应涉及朝向嘴和嘴的后续开口的触角卷曲。利用前者的观察，我们开发了定量涉及测量触手和嘴的顶端部之间的距离的馈送行为的简单且可靠的方法。至关重要的是（1）使用新鲜制备的GSH溶液，（2）使用谷胱甘肽的适当浓度，和（3）进行实验在实验室中具有均匀的光强度和没有强烈的气流，得到的可再现的测量GSH-准ð摄食行为。饲养反应般的行为也可以通过简单地增加媒体缺乏GSH在物理诱发。但是，这样的现象是短暂的，并经过15-30秒并不明显。因此，有必要对包括该控制在实验和测量馈送响应后才这样所造成的机械干扰的响应被完全停止。以最小化所引起的与谷胱甘肽溶液中加入可变流量的机械扰动引起的触手收缩的变化，这也将是可行的如前面19所描述来代替供试品溶液的手撒用的机械装置。的谷胱甘肽溶液机械化分配将使更严格地控​​制机械刺激的幅度和方向，使得它可以在所有的分配事件均匀，因此，内部标准化。 在该方法中，触手蔓延跨两个二测mensions;而在现实中，很少有触角也沿着第三个轴指向观察者传播。同样，触角的方向可以增加谷胱甘肽后更改。然而，平均触手分布在单个息肉的多个触须以及跨多个息肉归由二维测量以及触角的变化的方向引入的偏差。我们认为，这移至井，其中明确观察的触​​角并不总是可行的极端边缘的息肉，被排除在分析之外。此外，考虑相对触手蔓延，这是触手的比值之前，加入GSH的后扩散，并且不GSH处理后的触手蔓延的绝对值，作为馈送响应的测量值，可能会导致在最小化诱导的变异性的变化的在个别息肉的触手长度。测定谷胱甘肽诱导feedi这个协议NG应答可能是所有物种的水润同样有用。用于测量触手蔓延，从水螅的大量人口所获得的图像，它也有可能写出类似的可用于动物行为20分析的计算机算法。

Hydra is the most primitive organism possessing a nervous system and chemosensation for detecting reduced glutathione (GSH) for capturing the prey1. It feeds on a variety of animals such as nematode, crustacea, insect larvae, tadpoles and newly hatched fish1. The movement of these prey organisms causes mechanosensory discharge of the stinging capsules called nematocysts from hydra, which are inserted into the prey2. GSH present in the fluid released from the injured prey subsequently activates the feeding response in hydra which includes curling of the tentacles to bring the prey towards the mouth, opening of the mouth, and consequent engulfing of the prey. Multiple molecules, such as dopamine3, glutamate4, GABA, glycine5, NMDA receptors6, and allatotropin7, have been shown to be involved in the feeding response in hydra. It has also been shown that the chemosensory response induced by GSH is modulated by the feeding status of the animal such that starved hydra exhibited enhanced feeding response1. Such an increase in the GSH sensitivity is biologically relevant since under starvation hydra need to find its prey at higher sensitivity. 
Although the feeding response induced by GSH can be clearly observed under microscope, the methods typically used for measuring the feeding response observations are non-quantitative. In most of the cases, the time during which the mouth of the hydra remains open was taken as a measure of the feeding response8,9; whereas in another case, quantitation was based on the number of hydra out of a population showing the feeding response10. However, observing the mouth opening time of the hydra polyps is cumbersome and subject to variation induced by uncontrollable parameters such as the direction of the mouth orientation during observations. Similarly, since the feeding response is a quantitative parameter, population-based approaches are subject to variations/errors caused by the opinion or observational bias of the individual observer. To circumvent these issues we have developed a method for the relative quantification of the feeding response in hydra (Hydra vulgaris Ind-Pune11) based on the distance of the apical end of the tentacle from the mouth of the hydra polyp.

<table><tbody><tr><td>Cooled Incubator</td><td>Panasonic&amp;nbsp;</td><td>MIR-254-PE</td><td></td></tr><tr><td>Microscope</td><td>Leica</td><td>S8AP0&amp;nbsp;</td><td></td></tr><tr><td>Camera for the microscope</td><td>Leica&amp;nbsp;</td><td>EC3</td><td></td></tr><tr><td>Reduced glutathione</td><td>Sigma</td><td>G4251</td><td>Stored at 4 &amp;deg;C. Bring the bottle to room temperature before opening to avoid oxidation</td></tr><tr><td>Image editing program</td><td>GIMP</td><td>Version 2.8</td><td></td></tr></tbody></table>

measuring glutathione-induced feeding response in hydra

Hydra is among the most primitive organisms possessing a nervous system and chemosensation for detecting reduced glutathione (GSH) for capturing the prey. The movement of prey organisms causes mechanosensory discharge of the stinging cells called nematocysts from hydra, which are inserted into the prey. The feeding response in hydra, which includes curling of the tentacles to bring the prey towards the mouth, opening of the mouth and consequent engulfing of the prey, is triggered by GSH present in the fluid released from the injured prey. To be able to identify the molecular mechanism of the feeding response in hydra which is unknown to date, it is necessary to establish an assay to measure the feeding response. Here, we describe a simple method for the quantitation of the feeding response in which the distance between the apical end of the tentacle and mouth of hydra is measured and the ratio of such distance before and after the addition of GSH is determined. The ratio, called the relative tentacle spread, was found to give a measure of the feeding response. This assay was validated using a starvation model in which starved hydra show an enhanced feeding response in comparison with daily fed hydra.

谷胱甘肽导致水螅表现出对嘴吞噬猎物的目的触手卷曲。触手卷曲等带来的触角更接近hypostome根尖末端。这将导致减少的触手蔓延，或的触手与hypostome（ 图1）顶端末端之间的直线距离。相对触手蔓延，或平均触手之比之前流传，并添加谷胱甘肽后，均在多个息肉减少随着时间的推移。相对触手蔓延除了缺乏谷胱甘肽培养基之后，但是，只减少瞬时和达到单元值在大约一分钟内（ 图2）。饥饿是已知会导致增强诱导谷胱甘肽1,13取食行为的。测定此处描述的摄食行为的方法通过将饥饿模型进行了验证。触手分布在一分钟后加入谷胱甘肽是significantlÝ下为饥饿组相比，饱满组（p = 1×10 -16通过施加2尾t检验，以相等的方差）（ 图3）。 <img alt="图1" src="/files/ftp_upload/52178/52178fig1highres.jpg" width="675" /> 图1:测量平均值触手蔓延的方法。记录一个宽松水螅息肉的图像添加谷胱甘肽和嘴和每个息肉的触手的顶端末端之间的直线距离测定中使用的GIMP工具的像素数目计算之前。另一个图像添加GSH后获取，传播触手进行测量以类似的方式。 <img alt="图2" fo:content-width="5in" src="/files/ftp_upload/52178/52178fig2highres.jpg" width="525" /> 图2:在九头蛇的GSH-引起的摄食反应的定量。 Tentac文件添加如在图1中描述的和相对的触手蔓延记作触手的比之前传播并加入谷胱甘肽（14）后的GSH后测量扩散在不同的时间点。对于对照组的值表示加成水螅介质的未经谷胱甘肽（14）之后的相对触手蔓延。误差条代表±SEM。 <img alt="图3" src="/files/ftp_upload/52178/52178fig3highres.jpg" width="625" /> 图3:使用饥饿模型馈送响应的定量的方法的有效性。 X轴表示加入3μM的谷胱甘肽与饥饿（61例）和饱满（正= 66）组后的时间。

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Measuring Glutathione-induced Feeding Response in Hydra

Here we describe a simple assay for the quantification of the feeding response in hydra induced by the reduced form of glutathione. This assay relies on measuring the distance between the apical end of the tentacle and mouth of hydra.

测量水润谷胱甘肽诱导饲养响应

Hydra is among the most primitive organisms possessing a nervous system and chemosensation for detecting reduced glutathione (GSH) for capturing the prey. ...

measuring-glutathione-induced-feeding-response-in-hydra

Universidad San Sebastian

Research

JoVE Journal

Biology

11.3K 次观看.  India Institute of Science Education and Research, Pune. Here we describe a simple assay for the quantification of the feeding response in hydra induced by the reduced form of glutathione. This assay relies on measuring the distance between the apical end of the tentacle and mouth of hydra.

视频: Measuring Glutathione-induced Feeding Response in Hydra

Imaging Approaches to Assessments of Toxicological Oxidative Stress Using Genetically-encoded Fluorogenic Sensors

While oxidative stress is a commonly cited toxicological mechanism, conventional methods to study it suffer from a number of shortcomings, including destruction of the sample, introduction of potential artifacts, and a lack of specificity for the reactive species involved. Thus, there is a current need in the field of toxicology for non-destructive, sensitive, and specific methods that can be used to observe and quantify intracellular redox perturbations, more commonly referred to as oxidative stress. Here, we present a method for the use of two genetically-encoded fluorogenic sensors, roGFP2 and HyPer, to be used in live-cell imaging studies to observe xenobiotic-induced oxidative responses. roGFP2 equilibrates with the glutathione redox potential (EGSH), while HyPer directly detects hydrogen peroxide (H2O2). Both sensors can be expressed into various cell types via transfection or transduction, and can be targeted to specific cellular compartments. Most importantly, live-cell microscopy using these sensors offers high spatial and temporal resolution that is not possible using conventional methods. Changes in the fluorescence intensity monitored at 510 nm serves as the readout for both genetically-encoded fluorogenic sensors when sequentially excited by 404 nm and 488 nm light. This property makes both sensors ratiometric, eliminating common microscopy artifacts and correcting for differences in sensor expression between cells. This methodology can be applied across a variety of fluorometric platforms capable of exciting and collecting emissions at the prescribed wavelengths, making it suitable for use with confocal imaging systems, conventional wide-field microscopy, and plate readers. Both genetically-encoded fluorogenic sensors have been used in a variety of cell types and toxicological studies to monitor cellular EGSH and H2O2 generation in real-time. Outlined here is a standardized method that is widely adaptable across cell types and fluorometric platforms for the application of roGFP2 and HyPer in live-cell toxicological assessments of oxidative stress.

This manuscript describes the use of genetically-encoded fluorogenic reporters in an application of live-cell imaging for the examination of xenobiotic-induced oxidative stress. This experimental approach offers unparalleled spatiotemporal resolution, sensitivity, and specificity while avoiding many of the shortcomings of conventional methods used for the detection of toxicological oxidative stress.

用基因编码荧光传感器评估毒理学氧化应激的成像方法

While oxidative stress is a commonly cited toxicological mechanism, conventional methods to study it suffer from a number of shortcomings, including ...

科研

癌症研究

Combining Quantitative Food-intake Assays and Forcibly Activating Neurons to Study Appetite in Drosophila

Food consumption is under the tight control of the brain, which integrates the physiological status, palatability, and nutritional contents of the food, and issues commands to start or stop feeding. Deciphering the processes underlying the decision-making of timely and moderate feeding carries major implications in our understanding of physiological and psychological disorders related to feeding control. Simple, quantitative, and robust methods are required to measure the food ingestion of animals after experimental manipulation, such as forcibly increasing the activities of certain target neurons. Here, we introduced dye-labeling-based feeding assays to facilitate the neurogenetic study of feeding control in adult fruit flies. We review available feeding assays, and then describe our methods step-by-step from setup to analysis, which combine thermogenetic and optogenetic manipulation of neurons controlling feeding motivation with dye-labeled food intake assay. We also discuss the advantages and limitations of our methods, compared with other feeding assays, to help readers choose an appropriate assay.

Combining Quantitative Food-intake Assays and Forcibly Activating Neurons to Study Appetite in Drosophila

Quantitative food-intake assays with dyed food provide a robust and high-throughput means to evaluate feeding motivation. Combining the food consumption assay with thermogenetic and optogenetic screens is a powerful approach to investigate the neural circuits underlying appetite in adult Drosophila melanogaster.

在果蝇中结合定量食物摄入量测定和强迫激活神经元研究食欲

Food consumption is under the tight control of the brain, which integrates the physiological status, palatability, and nutritional contents of the food, ...

行为学

Measurement of Glutamate Uptake using Radiolabeled L-[3H]-Glutamate in Acute Transverse Slices Obtained from Rodent Resected Hippocampus

Glutamate removal from the extracellular space by high-affinity Na+-dependent transporters is essential to ensure that the brain&#39;s intrinsic connectivity mechanisms work properly and homeostasis is maintained. The hippocampus is a unique brain structure that manages higher cognitive functions, and is the subject of several studies regarding neurologic diseases. The investigation of physiological and pathological mechanisms in rodent models can benefit from acute hippocampal slice (AHS) preparations. AHS has the advantage of providing reliable information on cell function since the cytoarchitecture and synaptic circuits are preserved. Although AHS preparations are commonly used in neurochemistry laboratories, it is possible to find some methodological differences in the literature. Considering that distinctive slice preparation protocols might change the hippocampal regions analyzed, this current protocol proposes a standard technique for obtaining transverse AHS from resected hippocampus. This simple-to-perform protocol may be used in mice and rats&#39; experimental models and allow several ex vivo approaches investigating neurochemical dynamics (in dorsal, intermediate and ventral hippocampus) in different backgrounds (e.g., transgenic manipulations) or after in vivo manipulations (e.g., pharmacological treatments or suitable rodent models to study clinical disorders). After dissecting the hippocampus from the rodent brain, transverse slices along the septo-temporal axis (300 &#181;m thick) were obtained. These AHS contain distinct parts of the hippocampus and were subjected to an individual neurochemical investigation (as an example: neurotransmitter transporters using their respective substrates). As the hippocampus presents a high density of excitatory synapses, and glutamate is the most important neurotransmitter in the brain, the glutamatergic system is an interesting target for in vivo observed phenomena. Thus, the current protocol provides detailed steps to explore glutamate uptake in ex vivo AHS using L-[3H]-Glutamate. Using this protocol to investigate hippocampal function may help to better understand the influence of glutamate metabolism on mechanisms of neuroprotection or neurotoxicity.

<meta charset="utf8"></head><body>使用放射性标记的 L-[3H]-谷氨酸测量从啮齿动物切除的海马体获得的急性横切片中的谷氨酸摄取

This article describes a reliable and simple way to obtain ex vivo acute hippocampal transverse slices from mice and rats using a tissue chopper. Slices obtained from resected hippocampi can be submitted for functional glutamate uptake analysis to investigate glutamatergic system homeostasis.

使用放射性标记的 L-[3H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

Glutamate removal from the extracellular space by high-affinity Na+-dependent transporters is essential to ensure that the brain&#39;s intrinsic ...

生物化学

测量 秀丽隐杆 线虫食物摄入量和寿命的高通量测定

Quantifying Food Intake in Caenorhabditis elegans by Measuring Bacterial Clearance

Feeding is an essential biological process for an organism&#39;s growth, reproduction, and survival. This assay aims to measure the food intake of Caenorhabditis elegans&#160;(C. elegans), an important parameter when studying the genetics of aging or metabolism. In most species, feeding is determined by measuring the difference between the amount of food provided and the amount left after a given time interval. The method presented here uses the same strategy to determine the feeding of C. elegans. It measures the amount of bacteria, the food source of C. elegans, cleared within 72 h. This method uses 96-well microtiter plates and has allowed the screening of hundreds of drugs for their ability to modulate food intake at a speed and depth not possible in other animal models. The strength of this assay is that it allows to measure feeding and lifespan simultaneously and directly measures the disappearance of food and, thus, is based on the same principles used for other organisms, facilitating species-to-species comparison.

作者聚焦：探索脂毒性与 HFpEF 之间的关系 

This protocol describes an assay to quantify Caenorhabditis elegans feeding rate based on measuring the clearance of bacteria in liquid culture.

通过测量细菌清除率来量化 秀丽隐杆线虫 的食物摄入量

Feeding is an essential biological process for an organism&#39;s growth, reproduction, and survival. This assay aims to measure the food intake of ...

GSH/GSSG 测量 – 用于抗氧化剂研究的改进 OPA 检测

Rapid Quantification of Oxidized and Reduced Forms of Glutathione Using Ortho -phthalaldehyde in Cultured Mammalian Cells In Vitro

Glutathione has long been considered a key biomarker for determining the antioxidant response of the cell. Hence, it is a primary marker for reactive oxygen species studies. The method utilizes Ortho-phthalaldehyde (OPA) to quantify the cellular concentration of glutathione(s). OPA conjugates with reduced glutathione (GSH) via sulfhydryl binding to subsequently form an isoindole, resulting in a highly fluorescent conjugate. To attain an accurate result of both oxidized glutathione (GSSG) and GSH, a combination of masking agents and reducing agents, which have been implemented in this protocol, are required. Treatments may also impact cellular viability. Hence, normalization via protein assay is presented in this multiparametric assay. The assay demonstrates a pseudo-linear detection range of 0.234 - 30&#181;M (R2=0.9932&#177;0.007 (N=12)) specific to GSH. The proposed assay also allows for the determination of oxidized glutathione with the addition of the masking agent N-ethylmaleimide to bind reduced glutathione, and the reducing agent tris(2-carboxyethyl) phosphine is introduced to cleave the disulfide bond in GSSG to produce two molecules of GSH. The assay is used in combination with a validated bicinchoninic acid assay for protein quantification and an adenylate kinase assay for cytotoxicity assessment.

作者聚焦：创新巯基定量和生物标志物检测用于氧化应激研究 

Quantification of both oxidized and reduced forms of glutathione (GSSG and GSH, respectively) has been achieved through the use of Ortho-phthalaldehyde (OPA). OPA becomes highly fluorescent once conjugated to GSH but is unable to conjugate GSSG until reduced. Here, we describe a multiparametric assay to quantify both using protein quantification for normalization.

在体外使用 邻 苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

Glutathione has long been considered a key biomarker for determining the antioxidant response of the cell. Hence, it is a primary marker for reactive ...

测量水润谷胱甘肽诱导饲养响应

摘要

探索更多视频

用基因编码荧光传感器评估毒理学氧化应激的成像方法

在果蝇中结合定量食物摄入量测定和强迫激活神经元研究食欲

使用放射性标记的 L-[³H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

使用放射性标记的 L-[³H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

测量水润谷胱甘肽诱导饲养响应

摘要

探索更多视频

用基因编码荧光传感器评估毒理学氧化应激的成像方法

在果蝇中结合定量食物摄入量测定和强迫激活神经元研究食欲

使用放射性标记的 L-[3H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

使用放射性标记的 L-[3H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

通过测量细菌清除率来量化 秀丽隐杆线虫 的食物摄入量

通过测量细菌清除率来量化 秀丽隐杆线虫 的食物摄入量

通过测量细菌清除率来量化 秀丽隐杆线虫 的食物摄入量

在体外使用 邻 苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用 邻 苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用 邻 苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

使用放射性标记的 L-[³H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

使用放射性标记的 L-[³H]-谷氨酸测量从啮齿动物切除的海马获得的急性横切中谷氨酸摄取

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

通过测量细菌清除率来量化秀丽隐杆线虫的食物摄入量

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽

在体外使用邻苯二甲醛在培养的哺乳动物细胞中快速定量氧化和还原形式的谷胱甘肽