Copper

  • 文章类型: Journal Article
    植入物广泛用于骨科和牙科科学领域。钛(TI)及其合金已成为应用最广泛的植入材料,但植入物相关感染仍然是植入物手术后常见且严重的并发症.此外,钛表现出生物惰性,防止植入物和骨组织强烈结合,并可能导致植入物松动和脱落。因此,预防植入物感染和提高其骨诱导能力是重要目标。
    研究纳米银/聚乳酸乙醇酸(NSPTICU)涂层钛铜合金植入物的抗菌活性和骨诱导能力,为抑制植入物相关感染和促进骨整合提供新的途径。
    我们首先通过研究MC3T3-E1细胞的增殖和分化来检查NSPTICU植入物的体外成骨能力。此外,通过显微计算机断层扫描(micro-CT)研究了NSPTICU植入物诱导SD大鼠成骨活性的能力,苏木精-伊红(HE)染色,masson染色,免疫组织化学和范吉森(VG)染色。用革兰氏阳性金黄色葡萄球菌(Sa)和革兰氏阴性大肠杆菌(E。大肠杆菌)细菌。Sa被用作试验细菌,通过粗视标本采集研究了NSPTICU植入大鼠体内的抗菌能力,细菌菌落计数,HE染色和Giemsa染色。
    茜素红染色,碱性磷酸酶(ALP)染色,实时定量聚合酶链反应(qRT-PCR)和蛋白质印迹分析显示,NSPTICU促进MC3T3-E1细胞的成骨分化。体外抗菌结果表明,NSPTICU植入物表现出更好的抗菌性能。动物实验表明,NSPTICU可抑制炎症反应,促进骨缺损的修复。
    NSPTICU具有出色的抗菌和骨诱导能力,骨缺损的治疗具有广阔的应用前景。
    UNASSIGNED: Implants are widely used in the field of orthopedics and dental sciences. Titanium (TI) and its alloys have become the most widely used implant materials, but implant-associated infection remains a common and serious complication after implant surgery. In addition, titanium exhibits biological inertness, which prevents implants and bone tissue from binding strongly and may cause implants to loosen and fall out. Therefore, preventing implant infection and improving their bone induction ability are important goals.
    UNASSIGNED: To study the antibacterial activity and bone induction ability of titanium-copper alloy implants coated with nanosilver/poly (lactic-co-glycolic acid) (NSPTICU) and provide a new approach for inhibiting implant-associated infection and promoting bone integration.
    UNASSIGNED: We first examined the in vitro osteogenic ability of NSPTICU implants by studying the proliferation and differentiation of MC3T3-E1 cells. Furthermore, the ability of NSPTICU implants to induce osteogenic activity in SD rats was studied by micro-computed tomography (micro-CT), hematoxylin-eosin (HE) staining, masson staining, immunohistochemistry and van gieson (VG) staining. The antibacterial activity of NSPTICU in vitro was studied with gram-positive Staphylococcus aureus (Sa) and gram-negative Escherichia coli (E. coli) bacteria. Sa was used as the test bacterium, and the antibacterial ability of NSPTICU implanted in rats was studied by gross view specimen collection, bacterial colony counting, HE staining and Giemsa staining.
    UNASSIGNED: Alizarin red staining, alkaline phosphatase (ALP) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis showed that NSPTICU promoted the osteogenic differentiation of MC3T3-E1 cells. The in vitro antimicrobial results showed that the NSPTICU implants exhibited better antibacterial properties. Animal experiments showed that NSPTICU can inhibit inflammation and promote the repair of bone defects.
    UNASSIGNED: NSPTICU has excellent antibacterial and bone induction ability, and has broad application prospects in the treatment of bone defects related to orthopedics and dental sciences.
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  • 文章类型: Journal Article
    铜稳态是生物体内的一个基本过程,以独特的途径为特征,这些途径已经进化以满足特定需求,同时保留核心抗性机制。虽然这些系统在模型细菌中有很好的记录,有关适应寒冷环境的物种中铜抗性的信息很少。本研究调查了阿根廷白菊(JUB59-T)基因组中与铜稳态相关的潜在基因,一种从南极海水中分离出的精神耐受细菌。我们确定了几个编码类似于对铜稳态至关重要的蛋白质的基因,包括三个铜转运P1B型ATP酶序列。其中一个,被称为BaCopA1,被选择用于在酿酒酵母中克隆和表达。BaCopA1成功整合到酵母膜中,随后用洗涤剂提取。纯化的BaCopA1证明了在低温下催化ATP水解的能力。生成了各种BaCopA1构象的结构模型,并将其与嗜中和嗜热同源结构进行了比较。关键残基的显着保守性和这些蛋白质之间的结构相似性表明了铜转运的共同反应机制。这项研究首次报道了一种精神耐受性P1B-ATPase,该酶已以功能形式表达和纯化。
    Copper homeostasis is a fundamental process in organisms, characterised by unique pathways that have evolved to meet specific needs while preserving core resistance mechanisms. While these systems are well-documented in model bacteria, information on copper resistance in species adapted to cold environments is scarce. This study investigates the potential genes related to copper homeostasis in the genome of Bizionia argentinensis (JUB59-T), a psychrotolerant bacterium isolated from Antarctic seawater. We identified several genes encoding proteins analogous to those crucial for copper homeostasis, including three sequences of copper-transport P1B-type ATPases. One of these, referred to as BaCopA1, was chosen for cloning and expression in Saccharomyces cerevisiae. BaCopA1 was successfully integrated into yeast membranes and subsequently extracted with detergent. The purified BaCopA1 demonstrated the ability to catalyse ATP hydrolysis at low temperatures. Structural models of various BaCopA1 conformations were generated and compared with mesophilic and thermophilic homologous structures. The significant conservation of critical residues and structural similarity among these proteins suggest a shared reaction mechanism for copper transport. This study is the first to report a psychrotolerant P1B-ATPase that has been expressed and purified in a functional form.
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  • 文章类型: Journal Article
    背景:组织调理剂用于治疗和改善支持全口义齿的组织。另一方面,纳米技术的最新进展彻底改变了科学的各个领域,包括牙科。本研究旨在研究用于完整假体的基于氧化铜纳米颗粒的组织调理剂的新型抗菌应用。
    方法:本实验研究包括126个组织调理剂样品,其中含有不同浓度的氧化铜纳米颗粒(20%,10%,5%,2.5%,1.25%,0.625%,和0%w/w)。将样品与粪肠球菌一起孵育,铜绿假单胞菌,和白色念珠菌在24孔板中放置24小时。然后,将来自孔的样品重新孵育24小时,并对微生物进行计数。
    结果:含有粪肠球菌和铜绿假单胞菌的培养基在24小时后显示出不同纳米颗粒浓度之间的显着生长差异(P<0.001),显示随着纳米颗粒浓度的增加,细菌生长减少。两种细菌在20%浓度下均未显示任何生长。然而,48h后,白色念珠菌在不同纳米颗粒浓度之间的生长表现出显著差异(P<0.001),显示随着纳米粒子浓度的增加,生长减少。此外,在20%浓度下观察到最小的生长。
    结论:结论:CuO纳米粒子是使用绿色合成方法以合适的尺寸制备的。此外,含有CuO纳米颗粒的组织调理剂对粪肠球菌显示出可接受的抗菌性能,铜绿假单胞菌,还有白色念珠菌.
    BACKGROUND: Tissue conditioners are used for treating and improving the tissues supporting complete dentures. On the other hand, recent advances in nanotechnology have revolutionized various fields of science, including dentistry. The present study aimed to investigate novel antimicrobial applications of copper oxide nanoparticle-based tissue conditioner used in complete prostheses.
    METHODS: The present experimental study included 126 tissue conditioner samples with different concentrations of copper oxide nanoparticles (20%, 10%, 5%, 2.5%, 1.25%, 0.625%, and 0% w/w). The samples were incubated with Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans in 24-well plates for 24 h. Then, samples from the wells were re-incubated for 24 h, and the microorganisms were counted.
    RESULTS: The culture media containing E. faecalis and P. aeruginosa showed significantly different growth between different nanoparticle concentrations following 24 h (P < 0.001), showing a reduction in bacterial growth with increased nanoparticle concentration. Both bacteria did not show any growth at the 20% concentration. However, C. albicans showed significant differences in growth between different nanoparticle concentrations following 48 h (P < 0.001), showing a reduction in growth with increased nanoparticle concentration. Also, the least growth was observed at the 20% concentration.
    CONCLUSIONS: In conclusion, the CuO nanoparticles were prepared using a green synthesis methon in the suitable sizes. Moreover, the tissue conditioners containing CuO nanoparticles showed acceptable antimicrobial properties against E. faecalis, P. aeruginosa, and C. albicans.
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  • 文章类型: Journal Article
    背景:人体内葡萄糖浓度的有效监测需要在非酶葡萄糖传感器中利用电化学活性传感材料。然而,普遍存在的限制,如复杂的制造工艺,灵敏度较低,和不稳定性阻碍了它们的实际应用。在这里,在碳纤维纸(CP)上制备了Cu-Co-Ni-S三元硫化物纳米多孔网络结构,轻而易举,和可控技术通过分步循环伏安法,作为高性能葡萄糖传感器的优越的自支撑催化电极。
    结果:自支撑Cu-Co-Ni-S在CP的互连三维(3D)网络上的直接生长增强了复合材料的活性位点,改进的离子扩散动力学,显著促进了电子转移速率。Co,Ni,Cu,和S进一步促进葡萄糖电氧化。结构良好的Cu-Co-Ni-S/CP对葡萄糖具有出色的电催化性能,其线性度在0.3至16,000μM的宽范围内,灵敏度高达6829μAmM-1cm-2。此外,该新型传感器表现出优异的选择性和储存稳定性,可以成功评估人血清中的葡萄糖水平。值得注意的是,新型Cu-Co-Ni-S/CP具有良好的生物相容性,证明其体内葡萄糖监测的潜力。
    结论:提出的3D分层形态自支撑电极传感器,这证明了葡萄糖电氧化的有吸引力的分析行为,为下一代高性能葡萄糖传感器提供了巨大的希望。
    BACKGROUND: Efficient monitoring of glucose concentration in the human body necessitates the utilization of electrochemically active sensing materials in nonenzymatic glucose sensors. However, prevailing limitations such as intricate fabrication processes, lower sensitivity, and instability impede their practical application. Herein, ternary Cu-Co-Ni-S sulfides nanoporous network structure was synthesized on carbon fiber paper (CP) by an ultrafast, facile, and controllable technique through on-step cyclic voltammetry, serving as a superior self-supporting catalytic electrode for the high-performance glucose sensor.
    RESULTS: The direct growth of free-standing Cu-Co-Ni-S on the interconnected three-dimensional (3D) network of CP boosted the active site of the composites, improved ion diffusion kinetics, and significantly promoted the electron transfer rate. The multiple oxidation states and synergistic effects among Co, Ni, Cu, and S further promoted glucose electrooxidation. The well-architected Cu-Co-Ni-S/CP presented exceptional electrocatalytic properties for glucose with satisfied linearity of a broad range from 0.3 to 16,000 μM and high sensitivity of 6829 μA mM- 1 cm- 2. Furthermore, the novel sensor demonstrated excellent selectivity and storage stability, which could successfully evaluate the glucose levels in human serum. Notably, the novel Cu-Co-Ni-S/CP showed favorable biocompatibility, proving its potential for in vivo glucose monitoring.
    CONCLUSIONS: The proposed 3D hierarchical morphology self-supported electrode sensor, which demonstrates appealing analysis behavior for glucose electrooxidation, holds great promise for the next generation of high-performance glucose sensors.
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  • 文章类型: Journal Article
    铜(II),有机葡萄栽培中的重要杀菌剂,也作为葡萄酒氧化催化剂。然而,关于收获时酿酒葡萄中最大允许的铜(II)离子剂量对陈年葡萄酒质量的影响,目前可用的数据有限。这是本研究的重点。我们根据有机农业设定的限值,通过从含有三种初始金属浓度的必加酒生产白葡萄酒和红葡萄酒来研究铜(II)的影响。详细来说,铜(II)对发酵进化的影响,色彩特征,并对酚类化合物进行了评价。有趣的是,在发酵完成时,以最高允许的铜(II)剂量获得的白葡萄酒最初超过1.0mg/L的浓度。然而,储存一年后,铜(Ⅱ)含量低于0.2±0.01mg/L相反,红葡萄酒在发酵结束时显示铜(II)水平低于1.0mg/L,但最初的铜(II)水平显著影响天然花色苷,颜色强度,色调,和乙醛浓度。经过12个月的老化,在聚合物颜料中观察到显著差异,因此表明铜(II)对红酒颜色稳定性的潜在长期影响。
    Copper (II), a vital fungicide in organic viticulture, also acts as a wine oxidation catalyst. However, limited data are currently available on the impact that maximum allowed copper (II) ion doses in wine grapes at harvest can have on aged wine quality. This was the focus of the present study. We investigated the copper (II) effects by producing both white and red wines from musts containing three initial metal concentrations according to the limits set for organic farming. In detail, the influence of copper (II) on fermentation evolution, chromatic characteristics, and phenolic compounds was evaluated. Interestingly, the white wine obtained with the highest permitted copper (II) dose initially exceeded the concentration of 1.0 mg/L at fermentation completion. However, after one year of storage, the copper (II) content fell below 0.2 ± 0.01 mg/L. Conversely, red wines showed copper (II) levels below 1.0 mg/L at the end of fermentation, but the initial copper (II) level in musts significantly affected total native anthocyanins, color intensity, hue, and acetaldehyde concentration. After 12-month aging, significant differences were observed in polymeric pigments, thus suggesting a potential long-term effect of copper (II) on red wine color stability.
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  • 文章类型: Journal Article
    在人类健康研究领域,铜(Cu)的稳态由于其与病理状况的联系而受到越来越多的关注,包括糖尿病(DM)。最近的研究表明,与Cu稳态相关的蛋白质,如ATOX1,FDX1,ATP7A,ATPB,SLC31A1、p53和UPS,也有助于DM。角化,以Cu稳态失调和Cu过载为特征,已被发现会导致线粒体中的脂蛋白寡聚化,铁硫蛋白的损失,谷胱甘肽的消耗,活性氧的产生,细胞死亡。进一步研究角化症如何影响DM对于揭示其作用机制和确定有效的干预措施至关重要。在这篇文章中,本文综述了Cu稳态的分子机制以及Cu-Cu在DM发病机制中的作用。影响这些蛋白质的小分子药物的研究提供了从对症治疗到治疗DM的潜在原因的可能性。
    In the field of human health research, the homeostasis of copper (Cu) is receiving increased attention due to its connection to pathological conditions, including diabetes mellitus (DM). Recent studies have demonstrated that proteins associated with Cu homeostasis, such as ATOX1, FDX1, ATP7A, ATPB, SLC31A1, p53, and UPS, also contribute to DM. Cuproptosis, characterized by Cu homeostasis dysregulation and Cu overload, has been found to cause the oligomerization of lipoylated proteins in mitochondria, loss of iron-sulfur protein, depletion of glutathione, production of reactive oxygen species, and cell death. Further research into how cuproptosis affects DM is essential to uncover its mechanism of action and identify effective interventions. In this article, we review the molecular mechanism of Cu homeostasis and the role of cuproptosis in the pathogenesis of DM. The study of small-molecule drugs that affect these proteins offers the possibility of moving from symptomatic treatment to treating the underlying causes of DM.
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  • 文章类型: Journal Article
    这项研究提出了基于甲基丙烯酸-甲基丙烯酸甲酯(EudragitL100)作为Cu(II)吸附剂的纤维,产生抗菌复合物。EudragitL100,一种通过自由基聚合合成的阴离子共聚物,在二甲基甲酰胺(DMF)和乙醇(EtOH)中进行静电纺丝。通过22因子设计优化了静电纺丝工艺,具有独立变量(共聚物浓度和EtOH/DMF体积比)和在中心点的三次重复。在14%w/vEudragitL100和80/20EtOH/DMF体积比下获得最小的平均纤维直径(259±53nm)。使用扫描电子显微镜(SEM)对纤维进行了表征,衰减全反射模式红外光谱(FTIR-ATR),和差示扫描量热法(DSC)。伪二级机理解释了对Cu(II)的动力学吸附。纤维表现出43.70mg/g的最大吸附容量(qe)。DSC分析证实了Cu(II)的吸收,表明金属离子和共聚物网络之间的络合。复合纤维显示比未复合纤维更低的溶胀度。复合纤维对革兰氏阴性(铜绿假单胞菌)和革兰氏阳性(金黄色葡萄球菌)细菌表现出抑菌活性。这项研究成功地优化了静电纺丝工艺,以生产基于EudragitL100的细纤维,可用作水性介质中Cu(II)离子的吸附剂和控制细菌生长。
    This study presents fibers based on methacrylic acid-methyl methacrylate (Eudragit L100) as Cu(II) adsorbents, resulting in antimicrobial complexes. Eudragit L100, an anionic copolymer synthesized by radical polymerization, was electrospun in dimethylformamide (DMF) and ethanol (EtOH). The electrospinning process was optimized through a 22-factorial design, with independent variables (copolymer concentration and EtOH/DMF volume ratio) and three repetitions at the central point. The smallest average fiber diameter (259 ± 53 nm) was obtained at 14% w/v Eudragit L100 and 80/20 EtOH/DMF volume ratio. The fibers were characterized using scanning electron microscopy (SEM), infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR), and differential scanning calorimetry (DSC). The pseudo-second-order mechanism explained the kinetic adsorption toward Cu(II). The fibers exhibited a maximum adsorption capacity (qe) of 43.70 mg/g. The DSC analysis confirmed the Cu(II) absorption, indicating complexation between metallic ions and copolymer networks. The complexed fibers showed a lower degree of swelling than the non-complexed fibers. The complexed fibers exhibited bacteriostatic activity against Gram-negative (Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria. This study successfully optimized the electrospinning process to produce thin fibers based on Eudragit L100 for potential applications as adsorbents for Cu(II) ions in aqueous media and for controlling bacterial growth.
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  • 文章类型: Journal Article
    工业化扩张以来带来了许多环境问题,包括农业灌溉用水中的重金属污染。本研究利用微生物燃料电池技术产生生物电,去除砷,铜,铁,使用受污染的农业水作为底物,使用马氏芽孢杆菌作为生物催化剂。获得的电势和电流的结果为0.798V和3.519mA,分别,在操作的第六天,pH值为6.54,EC等于198.72mS/cm,去除99.08、56.08和91.39%的As浓度,Cu,Fe,分别,在72小时内获得。同样,总氮浓度,有机碳,失火,溶解的有机碳,化学需氧量减少了69.047、86.922、85.378、88.458和90.771%,分别。同时,显示的PDMAX为376.20±15.478mW/cm2,计算的内阻为42.550±12.353Ω。该技术在克服现有技术障碍方面取得了重要进展,因为工程微生物燃料电池是可访问的和可扩展的。它将通过自然减少有毒金属和电能来产生重要的价值,以可持续和负担得起的方式产生电流。
    Industrialization has brought many environmental problems since its expansion, including heavy metal contamination in water used for agricultural irrigation. This research uses microbial fuel cell technology to generate bioelectricity and remove arsenic, copper, and iron, using contaminated agricultural water as a substrate and Bacillus marisflavi as a biocatalyst. The results obtained for electrical potential and current were 0.798 V and 3.519 mA, respectively, on the sixth day of operation and the pH value was 6.54 with an EC equal to 198.72 mS/cm, with a removal of 99.08, 56.08, and 91.39% of the concentrations of As, Cu, and Fe, respectively, obtained in 72 h. Likewise, total nitrogen concentrations, organic carbon, loss on ignition, dissolved organic carbon, and chemical oxygen demand were reduced by 69.047, 86.922, 85.378, 88.458, and 90.771%, respectively. At the same time, the PDMAX shown was 376.20 ± 15.478 mW/cm2, with a calculated internal resistance of 42.550 ± 12.353 Ω. This technique presents an essential advance in overcoming existing technical barriers because the engineered microbial fuel cells are accessible and scalable. It will generate important value by naturally reducing toxic metals and electrical energy, producing electric currents in a sustainable and affordable way.
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  • 文章类型: Journal Article
    世界范围内发生的持续工业发展产生了开发具有越来越高的功能特性的新材料的需求。这种需要也适用于电力用途的基本材料,那是铜。在这篇文章中,我们对各种合金元素如Mg的影响进行了研究,In,Si,Nb,Hf,Sb,Ni,Al,Fe,Zr,Cr,Zn,P,Ag,Sc,Pb,Sn,Co,Ti,Mn,Te和Bi对ETP级铜的电学和力学性能的影响。该研究涉及使用重力压铸方法生产铜合金,合金添加量为0.1wt。%,0.3wt。%和0.5wt.%.所有产生的材料都经过冷加工以生产电线,随后均质化和退火。以这种方式生产的材料经过测试以确定其特定的电导率,抗拉强度,屈服强度,伸长率和维氏硬度(HV10规模)。
    The continuous industrial development that occurs worldwide generates the need to develop new materials with increasingly higher functional properties. This need also applies to the basic material for electricity purposes, which is copper. In this article, we carry out studies on the influence of various alloying elements such as Mg, In, Si, Nb, Hf, Sb, Ni, Al, Fe, Zr, Cr, Zn, P, Ag, Sc, Pb, Sn, Co, Ti, Mn, Te and Bi on the electrical and mechanical properties of ETP-grade copper. The research involves producing copper alloys using the gravity die casting method with alloy additions of 0.1 wt.%, 0.3 wt.% and 0.5 wt.%. All resulting materials are cold-worked to produce wires, which are subsequently homogenized and annealed. The materials produced in this manner undergo testing to determine their specific electrical conductivity, tensile strength, yield strength, elongation and Vickers hardness (HV10 scale).
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  • 文章类型: Journal Article
    多孔铜(Cu),不同的孔隙度,已通过粉末冶金路线使用尿素作为空间保持器。使用了两种形状的尿素颗粒,(i)针状和(ii)球形,为了研究空间支架形状对多孔Cu孔结构和力学性能的影响。在压缩试验下研究了多孔铜的压缩变形行为。多孔铜的孔隙结构特征和机械性能随空间保持器的形状而显着变化。尽管空间保持器形状对孔隙率的影响不是规则的,对机械性能的影响是有规律的。应力随着应变的增加而单调增加,应变硬化发生在塑性屈服阶段。弹性模量和屈服强度遵循幂律,与相对密度无关的空间保持器的形状。与不同经验发展的幂律关系相关的经验常数是不同的,根据空间支架的形状。使用众所周知的空间保持器方法获得弹性模量和屈服强度与间隔物含量之间的定量关系以控制本发明的多孔Cu或其他多孔金属和金属泡沫的机械性能。
    Porous copper (Cu), with varying porosities, has been made using carbamide as a space holder through the powder metallurgy route. Two shapes of carbamide particles were used, (i) needlelike and (ii) spherical, in order to investigate the effect of the space holder shape on the pore structure and mechanical properties of porous Cu. The compressive deformation behavior of porous Cu was studied under a compression test. The pores\' structural characteristics and mechanical properties of the porous Cu varied significantly with the shape of the space holder. Although the effect of the space holder shape on the porosity was not regular, the effect on the mechanical properties was regular. The stress increased monotonically with the increase in the strain, and strain hardening occurred at the plastic yield stage. The elastic modulus and yield strength followed the power law, with the relative density irrespective of the space holder shape. The empirical constants associated with different empirically developed power law relations were different, according to the shape of space holder. A quantitative relationship between the elastic modulus and yield strength and the spacer content was obtained to control the mechanical properties of the present porous Cu or other porous metals and metal foams using the well-known space holder method.
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