transaminase

转氨酶
  • 文章类型: Journal Article
    代谢工程微生物聚生体可以作为聚酰胺单体供应的有希望的生产平台。迄今为止,长链α的生物合成,由于正烷烃的惰性性质和整个合成途径的复杂性,来自正烷烃的ω-二胺具有挑战性。我们将工程化的Yarrowialipolytica模块与大肠杆菌模块相结合,以获得混合菌株微生物联盟,该微生物联盟可以催化正构烷烃有效的生物转化为相应的α,ω-二胺。构建了工程化的Y.lipolytica菌株(YALI10),其中缺失了负责β-氧化的两个基因和负责脂肪醛过氧化的五个基因。这种新构建的表达转氨酶(TA)的YALI10菌株可以从10mM正十二烷产生0.2mM1,12-十二烷二胺(40.1mg/L)。包含用于氧化正烷烃(OM)的工程Y.Lipolytica菌株和表达醛还原酶(AHR)和转氨酶(TA)的大肠杆菌胺化模块(AM)的微生物聚生体改善了从10mM正十二烷产生高达1.95mM(391mg/L)的1,12-二胺。最后,将表达羧酸还原酶(CAR)的大肠杆菌还原模块(RM)和sfp磷酸蒽环酰转移酶与OM和AM结合,通过催化将不需要的1,12-二酸还原为1,12-二醇,进一步提高了1,12-二胺的生产。其进一步经历胺化以得到作为目标产物的1,12-二胺。这种新构建的在一个锅中包含三个模块的混合菌株财团从10mM正十二烷产生4.1mM(41%;816mg/L)1,12-二氨基十二烷。本文报道的全细胞聚生体为各种α的生物合成提供了一种优雅的“绿色”替代品,来自相应正烷烃的ω-二胺(C8、C10、C12和C14)。
    Metabolically engineered microbial consortia can contribute as a promising production platform for the supply of polyamide monomers. To date, the biosynthesis of long-chain α,ω-diamines from n-alkanes is challenging because of the inert nature of n-alkanes and the complexity of the overall synthesis pathway. We combined an engineered Yarrowia lipolytica module with Escherichia coli modules to obtain a mixed strain microbial consortium that could catalyze an efficient biotransformation of n-alkanes into corresponding α,ω-diamines. The engineered Y. lipolytica strain was constructed (YALI10) wherein the two genes responsible for β-oxidation and the five genes responsible for the overoxidation of fatty aldehydes were deleted. This newly constructed YALI10 strain expressing transaminase (TA) could produce 0.2 mM 1,12-dodecanediamine (40.1 mg/L) from 10 mM n-dodecane. The microbial consortia comprising engineered Y. lipolytica strains for the oxidation of n-alkanes (OM) and an E. coli amination module (AM) expressing an aldehyde reductase (AHR) and transaminase (TA) improved the production of 1,12-diamine up to 1.95 mM (391 mg/L) from 10 mM n-dodecane. Finally, combining the E. coli reduction module (RM) expressing a carboxylic acid reductase (CAR) and an sfp phosphopantetheinyl transferase with OM and AM further improved the production of 1,12-diamine by catalyzing the reduction of undesired 1,12-diacids into 1,12-diols, which further undergo amination to give 1,12-diamine as the target product. This newly constructed mixed strain consortium comprising three modules in one pot gave 4.1 mM (41%; 816 mg/L) 1,12-diaminododecane from 10 mM n-dodecane. The whole-cell consortia reported herein present an elegant \"greener\" alternative for the biosynthesis of various α,ω-diamines (C8, C10, C12, and C14) from corresponding n-alkanes.
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  • 文章类型: Journal Article
    本研究报道了地衣芽孢杆菌野生种转氨酶的分离和部分纯化。将半纯化转氨酶固定在通过声化学方法合成的铜纳米花(NFs)上,并将其作为纳米生物催化剂进行了探索。优化了转氨酶NFs[TA@Cu3(PO4)2NF]的合成条件。合成的NFs显示蛋白质负载和活性产量-60±5%和70±5%,分别。通过扫描电子显微镜(SEM)和透射电子显微镜(TEM)检查了合成的杂化NFs的表面形貌,这表明平均尺寸约为1±0.5μm。傅里叶变换红外(FTIR)用于确认酶在固定化基质内的存在。此外,圆二色性和荧光光谱法也用于确认固定化材料中蛋白质的二级和三级结构的完整性。与游离酶相比,转氨酶杂种NF表现出增强的动力学特性和稳定性,并显示出高重用性。此外,证明了固定化转氨酶杂合NFs在拆分外消旋α-甲基苄胺中的潜在应用。
    This study reports the isolation and partial purification of transaminase from the wild species of Bacillus licheniformis. Semi-purified transaminase was immobilized on copper nanoflowers (NFs) synthesized through sonochemical method and explored it as a nanobiocatalyst. The conditions for the synthesis of transaminase NFs [TA@Cu3(PO4)2NF] were optimized. Synthesized NFs revealed the protein loading and activity yield-60 ± 5% and 70 ± 5%, respectively. The surface morphology of the synthesized hybrid NFs was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which revealed the average size to be around 1 ± 0.5 μm. Fourier-transform infrared (FTIR) was used to confirm the presence of the enzyme inside the immobilized matrix. In addition, circular dichroism and florescence spectroscopy were also used to confirm the integrity of the secondary and tertiary structures of the protein in the immobilized material. The transaminase hybrid NFs exhibited enhanced kinetic properties and stability over the free enzyme and revealed high reusability. Furthermore, the potential application of the immobilized transaminase hybrid NFs was demonstrated in the resolution of racemic α-methyl benzylamine.
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  • 文章类型: Journal Article
    (+)-新薄荷胺是用于合成高附加值化学品的重要工业前体。这里,我们报道了一种新的生物催化路线,通过使用ω-转氨酶对容易获得的(-)-薄荷酮底物进行胺化来合成()-新薄荷胺。通过筛选一组ω-转氨酶,来自弧菌JS17的ω-转氨酶被鉴定为对(-)-薄荷酮具有相当大的胺化活性,然后对该酶进行酶学性质表征。在优化条件下,在温和的水相中转化10mM(-)-薄荷酮,在24小时内产生4.7mM产物。使用廉价的起始材料(酮底物和氨基供体)和温和的反应条件的生物催化路线代表了(+)-新薄荷胺合成的简单和绿色方法。该方法强调了生物催化剂在合成非天然萜类胺衍生物中的潜力。
    (+)-Neomenthylamine is an important industrial precursor used to synthesize high value-added chemicals. Here, we report a novel biocatalytic route to synthesize (+)-neomenthylamine by amination of readily available (-)-menthone substrate using ω-transaminase. By screening a panel of ω-transaminases, an ω-transaminase from Vibrio fluvialis JS17 was identified with considerable amination activity to (-)-menthone, and then characterization of enzymatic properties was conducted for the enzyme. Under optimized conditions, 10 mM (-)-menthone was transformed in a mild aqueous phase with 4.7 mM product yielded in 24 h. The biocatalytic route using inexpensive starting materials (ketone substrate and amino donor) and mild reaction conditions represents an easy and green approach for (+)-neomenthylamine synthesis. This method underscores the potential of biocatalysts in the synthesis of unnatural terpenoid amine derivatives.
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  • 文章类型: Journal Article
    背景:(-)-柠檬烯,一种环状单萜,是一种重要的可再生化合物,广泛用作合成新的生物活性分子和精细化学品的关键组成部分。(-)-紫苏胺,衍生自(-)-柠檬烯,是一个非常有用的合成子,用于构建更复杂和功能相关的化学物质。
    目的:我们旨在报道一种更可持续和更有效的将(-)-柠檬烯区域特异性C-H胺化为(-)-紫苏胺的方法。
    结果:这里,我们首次报道了一种用于将廉价且易于获得的(-)-柠檬烯转化为(-)-紫苏胺的人工五-酶级联系统。该系统由细胞色素P450单加氧酶组成,乙醇脱氢酶和w-转氨酶的主要反应,以及甲酸脱氢酶和NADH氧化酶用于辅因子回收。优化后的多酶级联系统,10mM(-)-柠檬烯在一锅两步生物转化中顺利转化为5.4mM(-)-紫苏胺,表明(-)-柠檬烯的惰性C-H键的多酶C7区域特异性胺化的可行性。该方法代表了从类似天然产物生物催化合成衍生物的简洁有效的路线。
    BACKGROUND: (-)-Limonene, one of cyclic monoterpenes, is an important renewable compound used widely as a key building block for the synthesis of new biologically active molecules and fine chemicals. (-)-Perillamine, as derived from (-)-limonene, is a highly useful synthon for constructing more complicated and functionally relevant chemicals.
    OBJECTIVE: We aimed to report a more sustainable and more efficient method for the regiospecific C-H amination of (-)-limonene into (-)-perillamine.
    RESULTS: Here, we report an artificial penta-enzymatic cascade system for the transformation of the cheap and easily available (-)-limonene into (-)-perillamine for the first time. This system is composed of cytochrome P450 monooxygenase, alcohol dehydrogenase and w-transaminase for the main reactions, as well as formate dehydrogenase and NADH oxidase for cofactor recycling. After optimization of the multi-enzymatic cascade system, 10 mM (-)-limonene was smoothly converted into 5.4 mM (-)-perillamine in a one-pot two-step biotransformation, indicating the feasibility of multi-enzymatic C7-regiospecific amination of the inert C-H bond of (-)-limonene. This method represents a concise and efficient route for the biocatalytic synthesis of derivatives from similar natural products.
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  • 文章类型: Journal Article
    背景:银屑病患者肝功能异常的风险增加。
    目的:探讨比马单抗治疗的银屑病患者肝脏治疗引起的不良事件(TEAE)的发生率和肝脏参数的变化。
    方法:数据来自5个为期2年的3/3b期试验。肝脏TEAE,丙氨酸氨基转移酶(ALT)或天冬氨酸氨基转移酶(AST)的实验室升高,和肝纤维化的临床标志物的变化(纤维化-4[FIB-4]指数和AST血小板比指数[APRI])被报道。TEAE使用暴露调整发生率(EAIR)每100患者年(PY)呈现。
    结果:2,186例患者接受了≥1次bimekizumab剂量。超过2年,肝脏TEAE的EAIR为3.5/100PY,从第1年到第2年没有增加.ALT/AST升高>3倍和>5倍ULN的2年EAIR分别为2.3和0.6/100PY;比率与安慰剂相似,阿达木单抗,苏金单抗,和ustekinumab在对照研究期间。FIB-4和APRI分数在两年内没有增加,无论基线时的纤维化风险如何。
    结论:肥胖,糖尿病,血脂异常,长期饮酒,和药物改变是肝功能障碍的混杂因素。
    结论:bimekizumab的肝脏不良事件发生率在2年内是一致的;在3/3b期对照研究期间,转氨酶升高的发生率与比较者相似。
    BACKGROUND: Patients with psoriasis are at increased risk of liver function abnormalities.
    OBJECTIVE: Explore rates of hepatic treatment-emergent adverse events (TEAEs) and changes in liver parameters in bimekizumab-treated patients with psoriasis.
    METHODS: Data are reported from 5 phase 3/3b trials over 2 years. Hepatic TEAEs, laboratory elevations in alanine aminotransferase (ALT) or aspartate aminotransferase (AST), and changes in clinical markers of liver fibrosis (Fibrosis-4 [FIB-4] Index and AST to Platelet Ratio Index [APRI]) are reported. TEAEs are presented using exposure-adjusted incidence rates (EAIRs) per 100 patient-years (PY).
    RESULTS: 2186 patients received ≥1 bimekizumab dose. Over 2 years, the EAIR of hepatic TEAEs was 3.5/100 PY and did not increase from first to second year. 2-year EAIRs of ALT/AST elevations >3x and >5x the upper limit of normal were 2.3 and 0.6/100 PY; rates were similar to placebo, adalimumab, secukinumab, and ustekinumab during controlled study periods. FIB-4 and APRI scores did not increase through 2 years, regardless of fibrosis risk at baseline.
    CONCLUSIONS: Obesity, diabetes, dyslipidemia, chronic alcohol consumption, and medication changes are confounding factors for hepatic dysfunction.
    CONCLUSIONS: Rates of hepatic adverse events (AEs) with bimekizumab were consistent through 2 years; incidences of transaminase elevations were similar to comparators during phase 3/3b controlled study periods.
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  • 文章类型: Journal Article
    非酒精性脂肪性肝病(NAFLD)的特征是脂肪在肝脏中异位沉积,在没有其他次要原因的脂肪积累。NAFLD,包括丙氨酸转氨酶(ALT),和糖化血红蛋白(HbA1c),对于预测疾病的严重程度和预后具有重要意义。本研究旨在通过检测ALT水平来探讨2型糖尿病(T2DM)患者HbA1c与NAFLD的相关性。
    这项回顾性横断面研究纳入了130名T2DM和NAFLD患者。控制和未控制的T2DMNAFLD患者的HbA1c和ALT水平之间的关系,分别,被调查。根据性别和糖尿病控制进行分层,使用HbA1c水平作为血糖控制的标志。还比较了两组的血清ALT水平。
    参与者的平均年龄为50.2±5.7岁。参与者总数为130人,其中77人(59.3%)为女性,53人(40.7%)为男性。2型糖尿病患者数量不受控制(HbA1c>7%),和控制T2DM(HbA1c<7%)78(60%)和52(40%),分别。此外,46(35.3%)女性和32(24.7%)男性患有不受控制的T2DM,31名(23.8%)女性和21名(16.2%)男性患有T2DM。女性患者中不受控制和控制的T2DM的平均ALT水平分别为24.6±3.4和13.5±2.4。(P<0.05)。对于男性患者,分别为54.0±4.9和29.1±5.4(P=0.008)。
    T2DM合并NAFLD患者的HbA1c升高与ALT水平呈正相关。
    UNASSIGNED: Non-alcoholic fatty liver disease (NAFLD) is characterized by ectopic deposition of fat in the liver, in the absence of other secondary causes of fat buildup. The relationship between NAFLD, including alanine aminotransferase (ALT), and glycated haemoglobin (HbA1c), is important for predicting the severity of disease and prognosis. This study aims to investigate the association of HbA1c in type 2 diabetes mellitus (T2DM) patients with NAFLD via measuring the ALT levels.
    UNASSIGNED: This retrospective cross-sectional study enroled 130 patients with T2DM and NAFLD. The association between levels of HbA1c and ALT in patients of NAFLD with controlled and uncontrolled T2DM, respectively, was investigated. Stratification was done based on gender and diabetic control, using HbA1c levels as a marker of glycemic control. Serum ALT levels were also compared in both groups.
    UNASSIGNED: The mean age of the participants was 50.2±5.7 years. The total participants were 130, of which 77 (59.3%) were females and 53 (40.7%) were males. The numbers of patients having uncontrolled T2DM (HbA1c>7%), and controlled T2DM (HbA1c <7%) were 78 (60%) and 52 (40%), respectively. Moreover, 46 (35.3%) females and 32 (24.7%) males had uncontrolled T2DM, and 31 (23.8%) females and 21 (16.2%) males had controlled T2DM. The mean ALT level for uncontrolled and controlled T2DM in female patients was found to be 24.6±3.4 and 13.5±2.4, respectively, (P <0.05). For male patients, it was found to be 54.0±4.9 and 29.1±5.4, respectively (P=0.008).
    UNASSIGNED: There is a positive association between elevated HbA1c and ALT levels in T2DM patients with NAFLD.
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  • 文章类型: Journal Article
    拉曼光谱已用于测量在ω-转氨酶催化的转化中用于烟碱乙酰胆碱受体的正变构调节剂的药学相关模型胺中间体的浓度。开发了基于一维卷积神经网络的模型,将原始数据增强拉曼光谱直接转化为底物浓度,随着时间的推移,可以确定ω-转氨酶从酮到胺的转化。该模型显示出非常好的预测能力,对于建模中包含的光谱,R2值高于0.99,对于独立数据集,R2值高于0.964。然而,模型无法外推模型指定的浓度。所提出的工作显示了拉曼光谱作为生物催化反应的实时监测工具的潜力。
    Raman spectroscopy has been used to measure the concentration of a pharmaceutically relevant model amine intermediate for positive allosteric modulators of nicotinic acetylcholine receptor in a ω-transaminase-catalyzed conversion. A model based on a one-dimensional convolutional neural network was developed to translate raw data augmented Raman spectra directly into substrate concentrations, with which the conversion from ketone to amine by ω-transaminase could be determined over time. The model showed very good predictive capabilities, with R2 values higher than 0.99 for the spectra included in the modeling and 0.964 for an independent dataset. However, the model could not extrapolate outside the concentrations specified by the model. The presented work shows the potential of Raman spectroscopy as a real-time monitoring tool for biocatalytic reactions.
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  • 文章类型: Journal Article
    尽管光学纯氨基醇由于其广泛的适用性而需求量很大,它们仍然具有合成的挑战性,因为需要普遍制定的保护策略。这里,提出了一种多酶方法,可以克服这一障碍,从商品化学品中提供富含对映体的1,3-氨基醇。I型醛缩酶伪造了富含对映体的醛醇基序的碳骨架,随后进行酶促氨基转移。在通过不同亲核试剂和亲电子试剂制备的不同九种羟醛产品上测试了一组194个TA。由于(R)-和(S)-选择性TA的可用性,1,3-氨基醇基序的两种非对映异构体均可获得.两步法能够合成具有至多三个手性中心的所需氨基醇,在最终产物中de至多>97。
    Although optical pure amino alcohols are in high demand due to their widespread applicability, they still remain challenging to synthesize, since commonly elaborated protection strategies are required. Here, a multi-enzymatic methodology is presented that circumvents this obstacle furnishing enantioenriched 1,3-amino alcohols out of commodity chemicals. A Type I aldolase forged the carbon backbone with an enantioenriched aldol motif, which was subsequently subjected to enzymatic transamination. A panel of 194 TAs was tested on diverse nine aldol products prepared through different nucleophiles and electrophiles. Due to the availability of (R)- and (S)-selective TAs, both diastereomers of the 1,3-amino alcohol motif were accessible. A two-step process enabled the synthesis of the desired amino alcohols with up to three chiral centers with de up to >97 in the final products.
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  • 文章类型: Journal Article
    肝损伤伴随治疗性转基因表达的丧失可以是全身施用重组腺相关病毒(rAAV)的临床后遗症,当用于基因治疗时,和治疗效果的显着障碍。尽管如此,很难在临床前模型中复制这种表型,从而限制了该领域系统地研究潜在生物学机制和开发干预措施的能力。以前的动物模型集中在衣壳和转基因相关的免疫原性,但是同时存在的非转基因或载体抗原对治疗效果的影响,例如那些源自rAAV制备物中的污染核酸,还有待调查.在这项研究中,使用Ad5-CMV_GFP免疫的免疫活性BALB/cJ小鼠,和表达凝血因子VIII的rAAV制剂,含有绿色荧光蛋白(GFP)cDNA包装为P5相关污染物,我们建立了诱导转氨酶的模型,并观察rAAV给药后伴随的治疗效果降低。当GFPcDNA作为P5相关的rAAV污染物递送时,我们在脾CD8+T细胞中观察到强表位特异性抗GFP反应,这与丙氨酸和天冬氨酸氨基转移酶的升高相吻合并相关。此外,我们报告了可检测的循环FVIII蛋白显着减少,与对照小鼠相比。最后,当GFP作为污染物或转基因递送至Ad5-CMV_GFP免疫小鼠时,我们观察到AAV8衣壳特异性T细胞的检测升高。我们提出了这个模型作为研究AAV后肝毒性的潜在生物学的潜在工具,并证明了T细胞对AAV衣壳化非治疗性核酸产生的蛋白质的反应的潜力。干扰有效的基因转移。
    Liver injury with concomitant loss of therapeutic transgene expression can be a clinical sequela of systemic administration of recombinant adeno-associated virus (rAAV) when used for gene therapy, and a significant barrier to treatment efficacy. Despite this, it has been difficult to replicate this phenotype in preclinical models, thereby limiting the field\'s ability to systematically investigate underlying biological mechanisms and develop interventions. Prior animal models have focused on capsid and transgene-related immunogenicity, but the impact of concurrently present nontransgene or vector antigens on therapeutic efficacy, such as those derived from contaminating nucleic acids within rAAV preps, has yet to be investigated. In this study, using Ad5-CMV_GFP-immunized immunocompetent BALB/cJ mice, and a coagulation factor VIII expressing rAAV preparation that contains green flourescent protein (GFP) cDNA packaged as P5-associated contaminants, we establish a model to induce transaminitis and observe concomitant therapeutic efficacy reduction after rAAV administration. We observed strong epitope-specific anti-GFP responses in splenic CD8+ T cells when GFP cDNA was delivered as a P5-associated contaminant of rAAV, which coincided and correlated with alanine and aspartate aminotransferase elevations. Furthermore, we report a significant reduction in detectable circulating FVIII protein, as compared with control mice. Lastly, we observed an elevation in the detection of AAV8 capsid-specific T cells when GFP was delivered either as a contaminant or transgene to Ad5-CMV_GFP-immunized mice. We present this model as a potential tool to study the underlying biology of post-AAV hepatotoxicity and demonstrate the potential for T cell responses against proteins produced from AAV encapsidated nontherapeutic nucleic acids, to interfere with efficacious gene transfer.
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  • 文章类型: Journal Article
    共生系统在多个层面上紧密集成。氨基酸生物合成中的宿主-内共生体代谢互补性对于以树液为食的昆虫及其共生体尤为重要。在象鼻虫-纳多内共生中,内共生体酪氨酸合成途径的最后一步反应由宿主编码的转氨酶补充。根据以前其他昆虫的结果,我们怀疑这些转氨酶可能被转运到Nardonella细胞质中以产生酪氨酸。这里,我们在红棕榈象鼻虫的基因组中鉴定了五个转氨酶基因。采用实时定量RT-PCR,我们证实RfGOT1和RfGOT2A在细菌组中特异性表达。靶向这两个氨基转移酶基因的RNA干扰降低了细菌组中的酪氨酸水平。免疫荧光-FISH双标记定位分析显示RfGOT1和RfGOT2A存在于细菌细胞内,它们与纳顿拉细胞共同定位。免疫金透射电子显微镜显示RfGOT1和RfGOT2A在Nardonella和细菌细胞的细胞质中的定位。我们的数据显示,RfGOT1和RfGOT2A被转运到Nardonella细胞质中,与保留在Nardonella基因组中的基因协作以合成酪氨酸。我们的研究结果将增强对氨基酸生物合成中宿主和内共生体代谢整合的理解。
    Symbiotic systems are intimately integrated at multiple levels. Host-endosymbiont metabolic complementarity in amino acid biosynthesis is especially important for sap-feeding insects and their symbionts. In weevil-Nardonella endosymbiosis, the final step reaction of the endosymbiont tyrosine synthesis pathway is complemented by host-encoded aminotransferases. Based on previous results from other insects, we suspected that these aminotransferases were likely transported into the Nardonella cytoplasm to produce tyrosine. Here, we identified five aminotransferase genes in the genome of the red palm weevil. Using quantitative real-time RT-PCR, we confirmed that RfGOT1 and RfGOT2A were specifically expressed in the bacteriome. RNA interference targeting these two aminotransferase genes reduced the tyrosine level in the bacteriome. The immunofluorescence-FISH double labeling localization analysis revealed that RfGOT1 and RfGOT2A were present within the bacteriocyte, where they colocalized with Nardonella cells. Immunogold transmission electron microscopy demonstrated the localization of RfGOT1 and RfGOT2A in the cytosol of Nardonella and the bacteriocyte. Our data revealed that RfGOT1 and RfGOT2A are transported into the Nardonella cytoplasm to collaborate with genes retained in the Nardonella genome in order to synthesize tyrosine. The results of our study will enhance the understanding of the integration of host and endosymbiont metabolism in amino acid biosynthesis.
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