Target screening

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  • 文章类型: Journal Article
    个人消费健康补充剂的目的是通过营养调节达到稳健的状态。然而,一些不道德的制造商,以利润为动机,欺诈性地将具有治疗效果的药物或未经授权的成分掺入产品中,以提高产品性能。长期使用这些产品可能会无意中对人体健康造成伤害,并且无法促进营养保健。这些物质的非法包含在补肾和性增强产品中普遍存在。开发有效的分析方法来识别这些产品并筛选非法添加的成分可以有效地防止此类产品到达并留在市场上。开发并验证了5种保健品中90种磷酸二酯酶5型抑制剂(PDE-5is)的检测和定量的目标筛选方法。膳食补充剂的类型从片剂变化,胶囊,和蛋白质粉末到葡萄酒和饮料。用一步液相萃取完成样品制备。使用动态多反应监测(dMRM)技术,通过超高效液相色谱串联质谱(UPLC-MS/MS)在25分钟内有效地完成了90PDE-5is的筛选过程。在25至85ng/g或ng/mL的水平下检测到90个PDE-5is的LOD。这种新颖的目标方法是有效的,可以应用于常规的市场监管。在286批样品中,发现8个批次是阳性的。在健康产品中首次检测到三种PDE-5is。本文所展示的筛选方法将是用于快速筛选PDE-5is的有前途且强大的工具。
    The aim of individuals consuming health supplements is to attain a robust state through nutritional regulation. However, some unscrupulous manufacturers, motivated by profit, fraudulently incorporate drugs or unauthorized components with therapeutic effects into the product for instant product performance enhancement. The long-term use of these products may inadvertently inflict harm on human health and fail to promote nutritive healthcare. The illegal inclusion of these substances is prevalent in kidney-tonifying and sexuality-enhancing products. Developing effective analytical methods to identify these products and screen for illegal added ingredients can effectively prevent such products from reaching and remaining on the market. A target screening method for the detection and quantification of 90 phosphodiesterase type 5 inhibitors (PDE-5is) in 5 kinds of health products was developed and validated. The type of dietary supplements varied from tablets, capsules, and protein powder to wine and beverages. Sample preparation was completed with a one-step liquid phase extraction. The screening process of 90 PDE-5is was done efficiently within 25 min by ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) using the dynamic multiple reaction monitoring (dMRM) technique. The LODs of 90 PDE-5is were detected at levels ranging from 25 to 85 ng/g or ng/mL. This novel targeting methodology was effective and can be applied to routine market supervision. Among 286 batches of samples, 8 batches were found to be positive. Three kinds of PDE-5is were first detected in healthy products. The screening method demonstrated herein will be a promising and powerful tool for rapid screening of PDE-5is.
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  • 文章类型: Journal Article
    有机磷酸酯(OPEs)对人类和环境都有危害。本研究采用目标筛选方法,分析了珠江三角洲代表性污染场地土壤和地下水中OPEs的浓度和检测频率。利用自组织图(SOM)计算了土壤和地下水中OPEs的聚类和相关特征。对工业园区土壤和地下水中的OPEs进行了风险评估和分区。结果显示,在23种类型的OPEs中检测到14种。地下水中的总浓度(Σ23OPEs)范围为1.931至743.571ng/L,和0.218至79.578ng/g的土壤,前者显示高可溶性OPEs,检测频率和浓度高,而后者则表现出相反的趋势。SOM分析表明,土壤中OPEs的分布与地下水中的差异很大。在工业园区,OPEs在土壤和地下水中都构成了可接受的风险。土壤可以分为I区和II区,以及进入I区的地下水,II,III,并提出相应的管理建议。应用SOM分析OPEs的特性和分区,可为其他新污染物和污染场地提供参考。
    Organophosphate esters (OPEs) pose hazards to both humans and the environment. This study applied target screening to analyze the concentrations and detection frequencies of OPEs in the soil and groundwater of representative contaminated sites in the Pearl River Delta. The clusters and correlation characteristics of OPEs in soil and groundwater were calculated by self-organizing map (SOM). The risk assessment and partitions of OPEs in industrial park soil and groundwater were conducted. The results revealed that 14 out of 23 types of OPEs were detected. The total concentrations (Σ23OPEs) ranged from 1.931 to 743.571 ng/L in the groundwater, and 0.218 to 79.578 ng/g in the soil, the former showed highly soluble OPEs with high detection frequencies and concentrations, whereas the latter exhibited the opposite trend. SOM analysis revealed that the distribution of OPEs in the soil differed significantly from that in the groundwater. In the industrial park, OPEs posed acceptable risks in both the soil and groundwater. The soil could be categorized into Zone I and II, and the groundwater into Zone I, II, and III, with corresponding management recommendations. Applying SOM to analyze the characteristics and partitions of OPEs may provide references for other new pollutants and contaminated sites.
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  • 文章类型: Journal Article
    化学物质释放到环境中对水生生态系统构成重大威胁,这取决于与排放源的接近程度以及排放和动员的季节性动态。虽然欧洲水污染的时空信息正在增加,热带国家在季节性污染动态方面存在大量知识空白。因此,我们以肯尼亚西部的维多利亚湖南盆地为例,以确定污染的空间和季节性热点,量化对不同生物群体的毒性风险,并确定了季节性风险驱动因素。为此,我们分析了五个河流在四个不同季节的集水区的农业和污水处理厂的抓取水样。我们使用液相色谱与高分辨率质谱联用(LC-HRMS),目标列表为785种有机微污染物。共检测出307种化合物,浓度范围为0.3ng/L至6.6μg/L。使用基于混合物对标准测试生物的毒性的毒性单位(TU)方法,甲壳类动物被确定为受影响最大的群体,其次是藻类和鱼类。对于甲壳类动物来说,在所有样本中,超过了96%的慢性风险阈值,而56%的样本预计会有剧毒,2月旱季风险最高。在7月的旱季和5月的雨季记录了藻类和鱼类的高毒性单位值。Diazinon,吡虫啉,clothianidin和pirimiphos-methyl是甲壳动物毒性的主要驱动因素,而三氯生和不同的除草剂混合物在旱季和雨季会对藻类产生风险,分别。共有18种化学品被发现超过急性和慢性环境风险阈值。通过这项研究,强烈的污染时空格局,可以确认风险和风险驱动因素,告知监测和减排的优先次序,以提高水质和减少有毒风险。
    The release of chemicals into the environment presents a significant threat to aquatic ecosystems dependent on the proximity to emission sources and seasonal dynamics of emission and mobilization. While spatial-temporal information on water pollution in Europe is increasing, there are substantial knowledge gaps on seasonal pollution dynamics in tropical countries. Thus, we took Lake Victoria South Basin in western Kenya as a case study to identify spatial and seasonal hot spots of contamination, quantified toxic risks to different groups of organisms, and identified seasonal risk drivers. For this purpose, we analyzed grab water samples from five rivers with agricultural and wastewater treatment plants in their catchment in four different seasons. We used liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) with a target list of 785 organic micropollutants. A total of 307 compounds were detected with concentrations ranging from 0.3 ng/L to 6.6 μg/L. Using a Toxic Unit (TU) approach based on mixture toxicity to standard test organisms, crustaceans were identified as the most affected group followed by algae and fish. For crustaceans, chronic risk thresholds were exceeded in 96 % of all the samples, while 56 % of all samples are expected to be acutely toxic, with the highest risk in February during the dry season. High toxic unit values for algae and fish were recorded in July dry season and May wet season. Diazinon, imidacloprid, clothianidin and pirimiphos-methyl were the major drivers for crustacean toxicity while triclosan and different herbicide mixtures drive risks to algae in dry and wet seasons, respectively. A total of 18 chemicals were found to exceed acute and chronic environmental risk thresholds. With this study, strong spatial-temporal patterns of pollution, risks and risk drivers could be confirmed informing prioritization of monitoring and abatement to enhance water quality and reduce toxic risks.
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  • 文章类型: Journal Article
    有机合成化学品,包括杀虫剂,制药,和工业化合物,对海洋生态系统构成越来越大的威胁。尽管有潜在的影响,这些污染物在多个隔室中同时出现的数据,包括地表水,底部水,孔隙水,海洋环境中的沉积物仍然有限。这些信息对于评估沿海化学品状况至关重要,建立环境质量基准,进行全面的环境风险评估。在这项研究中,我们描述了针对农药的多方面监测运动,制药,表面活性剂,添加剂,和增塑剂在四个采样点的其他合成化学品中。一个地点位于受中南部城市定居点和旅游业影响的小科里莫湾,此外,我们采样了三个地点,高加索海峡,受智利巴塔哥尼亚北部城市定居点和鲑鱼养殖的影响。地表水,底部水,孔隙水,并在LC-和GC-HRMS平台上收集相邻沉积物样品进行目标筛选分析。我们的结果显示,在地表水中检测到多达83种化学物质,71在底部水中,101在孔隙水中,和244沉积物。为了增强数据的实用性和重用潜力,我们提供了有关已识别化学物质的作用方式和分子靶标的有价值的信息。这个全面的数据集有助于定义全球南部沿海地区的污染指纹,包括巴塔哥尼亚的偏远地区。它是未来研究的关键资源,包括海洋化学品风险评估,决策,以及这些地区环境保护的推进。
    Synthetic organic chemicals, including pesticides, pharmaceuticals, and industrial compounds, pose a growing threat to marine ecosystems. Despite their potential impact, data on the co-occurrence of these contaminants in multiple compartments, including surface water, bottom water, porewater, and sediment in the marine environment remains limited. Such information is critical for assessing coastal chemical status, establishing environmental quality benchmarks, and conducting comprehensive environmental risk assessments. In this study, we describe a multifaceted monitoring campaign targeting pesticides, pharmaceuticals, surfactants, additives, and plasticizers among other synthetic chemicals in four sampling sites. One site was located in the small Coliumo bay affected by urban settlements and tourism in central-south and additionally, we sampled three sites, Caucahue Channel, affected by urban settlements and salmon farming in northern Patagonia in Chile. Surface water, bottom water, porewater, and adjacent sediment samples were collected for target screening analysis in LC- and GC-HRMS platforms. Our results show the detection of up to 83 chemicals in surface water, 71 in bottom water, 101 in porewater, and 244 in sediments. To enhance data utility and reuse potential, we provide valuable information on the mode of action and molecular targets of the identified chemicals. This comprehensive dataset contributes to defining pollution fingerprints in coastal areas of the Global South, including remote regions in Patagonia. It serves as a critical resource for future research including marine chemical risk assessment, policymaking, and the advancement of environmental protection in these regions.
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  • 文章类型: Journal Article
    随着各种发酵食品中群落结构和组装机制的阐明,已经确定了显著影响或指导发酵的核心群落,并将其用于外源重组为合成微生物群落(SynComs)。这些SynComs模拟生态系统或在初学者中充当辅助或替代品,其疗效已得到广泛验证。然而,筛选和组装仍然是实施理论SynComs的主要限制因素,作为所需的菌株不能有效地获得和整合。扩大适用于食品发酵中SynComs的菌株筛选方法,这篇综述总结了使用SynComs研究社区进化或相互作用以及提高食品发酵质量的最新研究趋势,以及构建合成社区的具体过程。基于基因的新型筛选方式的潜力,讨论了食品微生物筛选中的酶和代谢物,同时强调优化装配以促进合成社区发展的战略。
    With the elucidation of community structures and assembly mechanisms in various fermented foods, core communities that significantly influence or guide fermentation have been pinpointed and used for exogenous restructuring into synthetic microbial communities (SynComs). These SynComs simulate ecological systems or function as adjuncts or substitutes in starters, and their efficacy has been widely verified. However, screening and assembly are still the main limiting factors for implementing theoretic SynComs, as desired strains cannot be effectively obtained and integrated. To expand strain screening methods suitable for SynComs in food fermentation, this review summarizes the recent research trends in using SynComs to study community evolution or interaction and improve the quality of food fermentation, as well as the specific process of constructing synthetic communities. The potential for novel screening modalities based on genes, enzymes and metabolites in food microbial screening is discussed, along with the emphasis on strategies to optimize assembly for facilitating the development of synthetic communities.
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  • 文章类型: English Abstract
    中医药是中国古代科学的宝贵财富,是开启中华文明宝库的钥匙。阐明中药的疗效和作用机理,科学家一直在从事分子基础和调控目标的研究。分子对接是一种计算机辅助药物设计方法,能够可视化组分和靶蛋白之间的相互作用。随着中医药现代化进程的推进以及算法和计算能力的进步,分子对接已成为中药新药开发的重要手段。本文综述了近年来分子对接在中药开发中的研究进展,旨在为进一步筛选有效成分提供有价值的参考,为促进中药新药的开发提供见解。
    Traditional Chinese medicine is precious treasure of ancient Chinese science and a key to unlocking the treasure trove of Chinese civilization. To elucidate the efficacy and mechanism of traditional Chinese medicines, scientists have been engaged in the research on the molecular basis and regulatory targets. Molecular docking is a computer-aided drug design method capable of visualizing the interaction between components and target proteins. With the progress in the modernization of traditional Chinese medicine and the advancement of algorithms and computing power, molecular docking has become an essential approach in the development of new traditional Chinese medicines. This article summarizes the recent research progress in molecular docking in the development of traditional Chinese medicine, aiming to provide valuable references for further screening of active components and offering insights for improving the development of new traditional Chinese medicines.
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  • 文章类型: Journal Article
    液相色谱(LC)或气相色谱(GC)结合高分辨率质谱(HRMS)是一种通用的分析方法,用于分析环境和生物样品中可以发现的数千种化学污染物。虽然处理这些复杂数据集的工具已经改进,仍然没有用于有针对性的筛查分析的完全自动化的工作流程。在这里,我们提出了一个基于R的工作流程,能够应对具有挑战性的数据,如嘈杂的离子色谱图,保留时间偏移,和多个峰值模式。工作流程可以应用于在具有电子电离的GC(GC-EI)和与电喷雾电离耦合的LC之后以负和正模式(LC-ESINeg/LC-ESIpos)记录的HRMS数据的批次,以完全无监督地执行峰注释和定量。我们使用地表水提取物的OrbitrapHRMS数据将自动目标筛选(ATS)工作流程与使用供应商软件TraceFinder执行的数据评估以及MZmine软件中已建立的半自动分析工作流程进行比较。与已建立的MZmine模块相比,ATS方法提高了峰值注释的整体评估性能,而无需进行任何事后校正。整体精度从0.80提高到0.86(LC-ESIpos),从0.77到0.83(LC-ESneg),从0.67到0.76(GC-EI)。与使用TraceFinder的手动定量相比,ATS定量的平均平均百分比误差约为30%。ATS工作流程可实现GC和LC-HRMS数据的时效性分析,并在无需人工干预的情况下,加速并提高了目标筛选在具有大量分析物和样本量的研究中的适用性。
    Liquid chromatography (LC) or gas chromatography (GC) coupled to high-resolution mass spectrometry (HRMS) is a versatile analytical method for the analysis of thousands of chemical pollutants that can be found in environmental and biological samples. While the tools for handling such complex datasets have improved, there are still no fully automated workflows for targeted screening analysis. Here we present an R-based workflow that is able to cope with challenging data like noisy ion chromatograms, retention time shifts, and multiple peak patterns. The workflow can be applied to batches of HRMS data recorded after GC with electron ionization (GC-EI) and LC coupled to electrospray ionization in both negative and positive mode (LC-ESIneg/LC-ESIpos) to perform peak annotation and quantitation fully unsupervised. We used Orbitrap HRMS data of surface water extracts to compare the Automated Target Screening (ATS) workflow with data evaluations performed with the vendor software TraceFinder and the established semi-automated analysis workflow in the MZmine software. The ATS approach increased the overall evaluation performance of the peak annotation compared to the established MZmine module without the need for any post-hoc corrections. The overall accuracy increased from 0.80 to 0.86 (LC-ESIpos), from 0.77 to 0.83 (LC-ESIneg), and from 0.67 to 0.76 (GC-EI). The mean average percentage errors for quantification of ATS were around 30% compared to the manual quantification with TraceFinder. The ATS workflow enables time-efficient analysis of GC- and LC-HRMS data and accelerates and improves the applicability of target screening in studies with a large number of analytes and sample sizes without the need for manual intervention.
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  • 文章类型: Journal Article
    几个欧洲国家的监测数据表明,欧洲刺猬(Erinaceuseuropaeus)种群数量正在减少,并研究探索下降的原因,包括暴露于潜在有害的异源生物和金属,可能会通知保护措施,以保护该物种在野外。刺猬是居住在地面上的哺乳动物,以一系列昆虫为食,slugs,蜗牛,蚯蚓,和鸡蛋一样,活的脊椎动物,还有腐肉,包括代表食物链更高级别的先端食肉动物的尸体。因此,刺猬与栖息地和猎物中存在的污染物密切接触。这篇评论调查了有关刺猬中金属和有机异种生物发生的研究。这项研究发现,各种各样的不同农药;持久性有机污染物(POPs),包括有机氯化合物和溴化阻燃剂(BFR);以及有毒重金属可以检测到。一些化合物以致死浓度出现,有些与对刺猬健康和生存的潜在不利影响有关。由于他们的生态,结合使用刺作为采样材料的非侵入性采样技术的机会,我们建议欧洲刺猬是一种相关的生物指示物种,用于监测陆地野生动植物在城市和农村环境中对潜在有毒物质的暴露。
    Monitoring data from several European countries indicate that European hedgehog (Erinaceus europaeus) populations are declining, and research exploring the causes of the decline, including exposure to potentially harmful xenobiotics and metals, may inform conservation initiatives to protect this species in the wild. Hedgehogs are ground-dwelling mammals, feeding on a range of insects, slugs, snails, and earthworms, as well as eggs, live vertebrates, and carrion, including carcasses of apex predator species representing higher levels of the food chain. Consequently, hedgehogs come into close contact with contaminants present in their habitats and prey. This review investigated the studies available on the subject of the occurrence of metals and organic xenobiotics in hedgehogs. This study found that a vast range of different pesticides; persistent organic pollutants (POPs), including organochlorine compounds and brominated flame retardants (BFRs); as well as toxic heavy metals could be detected. Some compounds occurred in lethal concentrations, and some were associated with a potential adverse effect on hedgehog health and survival. Due to their ecology, combined with the opportunity to apply non-invasive sampling techniques using spines as sampling material, we suggest that the European hedgehog is a relevant bioindicator species for monitoring the exposure of terrestrial wildlife to potential toxicants in urban and rural environments.
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  • 文章类型: Journal Article
    苏云金芽孢杆菌毒素作为杀虫剂的广泛使用带来了抗性问题。抗独特型纳米抗体方法为抗性管理和毒素进化提供了新的策略。在这项研究中,针对Cry2Aa毒素的受体结合区结构域II产生的单克隆抗体被用作筛选具有杀虫活性的材料的靶标。经过四轮筛选,抗独特型纳米抗体1C12从天然羊驼纳米抗体噬菌体展示文库中获得。为了更好地分析1C12的活性,大肠杆菌BL21(DE3)表达了可溶性1C12。结果表明,1C12不仅结合两种鳞翅目物种的中肠刷状缘膜囊泡(BBMV)和三种鳞翅目物种的钙黏着蛋白CR9-CR11,而且还抑制Cry2Aa毒素与CR9-CR11的结合。昆虫生物分析表明,可溶性1C12导致棉铃虫和小菜蛾幼虫死亡率分别为25.65%和23.61%,分别。尽管1C12具有较低的杀虫活性,可溶性1C12具有筛选鳞翅目钙粘蛋白毒素结合区的广谱识别的能力,可用于鉴定其他鳞翅目钙粘蛋白的毒素结合区以及Cry2Aa毒素的后续进化。本研究展示了筛选新型杀虫剂生产的新策略。
    The widespread use of Bacillus thuringiensis toxins as insecticides has brought about resistance problems. Anti-idiotypic nanobody approaches provide new strategies for resistance management and toxin evolution. In this study, the monoclonal antibody generated against the receptor binding region Domain II of Cry2Aa toxin was used as a target to screen materials with insecticidal activity. After four rounds of screening, anti-idiotypic nanobody 1C12 was obtained from the natural alpaca nanobody phage display library. To better analyze the activity of 1C12, soluble 1C12 was expressed by the Escherichia coli BL21 (DE3). The results showed that 1C12 not only binds the midgut brush border membrane vesicles (BBMV) of two lepidopteran species and cadherin CR9-CR11 of three lepidopteran species but also inhibits Cry2Aa toxins from binding to CR9-CR11. The insect bioassay showed that soluble 1C12 caused 25.65% and 23.61% larvae mortality of Helicoverpa armigera and Plutella xylostella, respectively. Although 1C12 has low insecticidal activity, soluble 1C12 possesses the ability to screen a broad-spectrum recognition of the toxin binding region of lepidopteran cadherins and can be used for the identification of the toxin binding region of other lepidopteran cadherins and the subsequent evolution of Cry2Aa toxin. The present study demonstrates a new strategy to screen for the production of novel insecticides.
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  • 文章类型: Journal Article
    挥发性化合物的测定对于蜂蜜香气的化学表征及其与感官特征和植物来源的相关性至关重要。本研究描述了发展,优化和验证新的,采用顶空固相微萃取-气相色谱/质谱联用技术(HS-SPME-GC-MS)测定蜂蜜中挥发性物质的方法简单可靠。SPME条件的优化表明,蜂蜜:水的比例(2:1)和孵育温度(60°C)是最关键的参数。用中等极性VarianCP-Select624柱进行气相色谱,并确定许多化合物的实验保留指数作为可疑分析的附加识别特征。同时使用四种内标氯苯,二苯甲酮,2-戊醇和4-甲基-2-戊酮与基质匹配的校准提高了方法的准确性,达到了73-114%的回收率,重复性在3.9%至19%的相对标准偏差之间。此外,验证了HS-SPME对静态顶空技术的优越性,其灵敏度提高了4至9倍。对30个希腊蜂蜜样品和53个属于不同化学类别的挥发性化合物进行了目标和可疑筛查,如烷烃,醛类,酮,酒精,和酯的定量浓度范围为3.1μgkg-1(柠檬烯)至20mgkg-1(苯乙醛)。新发现之一是在希腊松蜂蜜中检测到Myrtenol和在希腊橡木蜂蜜中检测到2,3-丁二醇。为了基于挥发物含量对蜂蜜进行化学表征,所开发的分析方案可以是有价值的工具。
    The determination of volatile compounds is essential for the chemical characterisation of honey\'s aroma and its correlation to its sensory profile and botanical origin. The present study describes the development, optimization and validation of a new, simple and reliable method for the determination of volatile compounds in honey using headspace solid-phase microextraction combined with gas chromatography/mass spectrometry (HS-SPME-GC-MS). The optimization of the SPME conditions showed that the ratio of honey: water (2:1) and the incubation temperature (60 °C) are the most critical parameters. Gas chromatography was performed with medium polar Varian CP-Select 624 column and the experimental Retention Index for a number of compounds was determined as an additional identification feature for suspect analysis. The simultaneous use of four internal standards chlorobenzene, benzophenone, 2-pentanol and 4-methyl-2-pentanone and matrix matched calibration enhanced method accuracy achieving recoveries 73-114 % and repeatability ranging between 3.9 and 19 % relative standard deviations. Furthermore, the superiority of the HS-SPME to static head space technique was verified exhibiting four-to nine-fold higher sensitivity. Target and suspect screening were applied to 30 Greek honey samples and 53 volatile compounds belonging to different chemical classes, such as alkanes, aldehydes, ketones, alcohols, and esters were identified with quantified concentrations ranging between 3.1 μg kg-1 (Limonene) up to 20 mg kg-1 (Benzeneacetaldehyde). Among the new findings is the detection of Myrtenol in Greek pine honey and 2,3-butanediol in Greek oak honey. The developed analytical protocol can be a valuable tool in order to chemically characterize honey based on the volatile content.
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