1HNMR

1HNMR
  • DOI:
    文章类型: Journal Article
    目的:恶性胸腔积液(MPE)是肺癌的常见并发症,预后较差。良性胸腔积液(BPE),如结核性和肺炎性胸腔积液,通常预后良好。MPE和BPE之间的鉴别诊断仍然是临床挑战。
    方法:52MPE,93BPE,和他们相应的血清样品通过氢核磁共振(1HNMR)为基础的代谢组学分析。
    结果:1HNMR研究表明,与BPE患者相比,MPE中的一些氨基酸和甜菜碱在胸腔积液和血清中发生了显着变化。MPE患者的血清葡萄糖和谷氨酰胺水平与胸腔积液(r>0.6)有很强的正相关。在区分MPE和BPE时,胸腔积液或血清中代谢物的受试者工作特征曲线下面积(AUROC)值小于0.805。使用胸腔积液-谷氨酸的血清比率来区分MPE和BPE,观察到AUROC值提高了0.901。15个双盲样本进一步验证。
    结论:与BPE患者相比,MPE中的氨基酸和甜菜碱在胸腔积液和血清中明显改变。通过1HNMR分析,胸腔积液与血清谷氨酸的比值可能有助于BPE的MPE的快速诊断。
    OBJECTIVE: Malignant pleural effusion (MPE) is a common complication of lung cancer with poor prognosis. Benign pleural effusion (BPE), such as tuberculous and pneumonic pleural effusion, usually has a good prognosis. Differential diagnosis between MPE and BPE remains a clinical challenge.
    METHODS: 52 MPE, 93 BPE, and their corresponding serum samples were analyzed by hydrogen nuclear magnetic resonance (1HNMR) based metabolomics.
    RESULTS: The 1HNMR study showed that some amino acids and betaine in MPE are significantly altered in pleural effusion and serum compared to BPE patients. Levels of serum glucose and glutamine have strong positive correlation with those in pleural effusion (r>0.6) for MPE patients. The area under the receiver operating characteristic curve (AUROC) values of metabolites in pleural effusion or serum were less than 0.805 in differentiating MPE from BPE. Improved an AUROC value of 0.901 was observed using pleural effusion-serum ratios of glutamic acid in differentiating MPE from BPE, which was further validated by 15 double-blind samples.
    CONCLUSIONS: Compared with BPE patients, amino acids and betaine in MPE are significantly altered in pleural effusion and serum. Pleural effusion-serum ratio of glutamic acid may contribute to the rapid diagnosis of MPE from BPE by 1HNMR analysis.
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  • 文章类型: Journal Article
    目的:开发了基于酰胺连接的直链淀粉的前药,用于甲芬那酸的结肠靶向释放。材料与方法:用分光光度法研究了前药的活化,酶联免疫吸附试验评价了不同浓度的前药对环氧合酶-1(COX-1)和环氧合酶-2(COX-2)的抑制作用,通过扫描电子显微镜监测前药在生理条件下的行为。结果:前药在无酶的模拟胃介质和模拟肠介质(SIM)中的活化能力较差,但在胰酶中预孵育,然后在含氨肽酶的SIM中处理导致前药的显着活化。结论:酰胺连接的直链淀粉-甲芬那酸缀合物在模拟胃介质中显示出缓慢释放,在SIM中显示出受控释放,而胰酶在药物释放中起重要作用。
    Aim: Amide-linked amylose-based prodrugs were developed for colon-targeted release of mefenamic acid. Materials & methods: Activation of prodrug was studied spectrophotometrically, enzyme-linked immunosorbent assay appraised cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) inhibition at different concentrations of the prodrug, the behavior of prodrug under physiological conditions was monitored by scanning electron microscopy. Results: Prodrug was poorly activated in the enzyme-free simulated gastric media and simulated intestinal media (SIM) but preincubation in pancreatin followed by treatment in aminopeptidase containing SIM led to a significant activation of prodrug. Conclusion: Amide-linked amylose-mefenamic acid conjugates showed a slow release in simulated gastric media and a controlled release in SIM with pancreatin playing an important role in drug release.
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  • 文章类型: Journal Article
    背景:2型糖尿病(T2DM)是严重肢体缺血(CLI)发展的重要危险因素,外周动脉疾病的最晚期。T2DM和CLI的同时存在通常会导致不良后果,即截肢。
    目的:确定改善T2DM高危人群CLI筛查的生物标志物。
    方法:我们研究了113名T2DM患者的血清代谢组分布,其中有CLI(n=23,G2)和无CLI(n=45,G0:无下肢狭窄(LLS)和n=45,G1:LLS<50%),采用氢核磁共振(1HNMR)方法。主成分分析(PCA)和偏最小二乘判别分析(PLS-DA)用于分析1HNMR数据。
    结果:在血清样本中确定了20种潜在的代谢产物,这些代谢产物可以区分T2DM和CLI(G2)患者与无LLS(G0)的非CLI患者。测试集样本的PLS-DA模型的正确分类百分比为G0和G2组的85%(n=20)和100%(n=5)。分别。将具有LLS<50%(G1)的非CLI患者投射在使用20种区分性代谢物构建的PCA抽象空间上。前瞻性随访11例T2DM和LLS<50%的患者,4年后测量他们的踝肱指数(ABI)。PCA模型的预测与通过ABI值获得的预测之间存在有希望的一致性。
    结论:研究结果表明,需要确认血液潜在代谢生物标志物作为ABI的补充,用于在一大群T2DM高危人群中筛查CLI。
    BACKGROUND: Type 2 diabetes mellitus (T2DM) is a significant risk factor for the development of critical limb ischemia (CLI), the most advanced stage of peripheral arterial disease. The concurrent existence of T2DM and CLI often leads to adverse outcomes, namely limb amputation.
    OBJECTIVE: To identify biomarkers for improving the screening of CLI in high-risk people with T2DM.
    METHODS: We investigated metabolome profiles in serum samples of 113 T2DM people with CLI (n = 23, G2) and without CLI (n = 45, G0: no lower limb stenosis (LLS) and n = 45, G1: LLS < 50%), using hydrogen nuclear magnetic resonance (1H NMR) approach. Principle component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were used to analyze 1H NMR data.
    RESULTS: Twenty potential metabolites that could discriminate people with T2DM and CLI (G2) from non-CLI patients without LLS (G0) were determined in serum samples. The correct percent of classification for the PLS-DA model for the test set samples was 85% (n = 20) and 100% (n = 5) for G0 and G2 groups, respectively. Non-CLI patients with LLS < 50% (G1) were projected on the PCA abstract space built using 20 discriminatory metabolites. Eleven people with T2DM and LLS < 50% were prospectively followed, and their ankle-brachial index (ABI) was measured after 4 years. A promising agreement existed between the PCA model\'s predictions and those obtained by ABI values.
    CONCLUSIONS: The findings suggest that confirmation of blood potential metabolic biomarkers as a complement to ABI for screening of CLI in a large group of high-risk people with T2DM is needed.
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  • 文章类型: Journal Article
    植物内生菌的存在是不可否认的,但是它们在宿主植物生物合成途径中的参与程度尚不清楚。植物中杀菌剂处理的结果各不相同。发现紫杉中的杀菌剂处理降低了紫杉醇的含量。在木薯中,ProntoPlus和Folicur处理与植物中麦角生物碱的消失相吻合。在水仙假水仙简历中。Carlton,杀菌剂的混合物降低了生物碱的浓度并改变了碳水化合物的代谢。用Folicur处理的Jacobaea植物降低了吡咯啶生物碱的含量。到目前为止,还没有任何关于内生真菌参与长春花生物碱生产的研究。尽管有关于内生真菌分离的报道,来自C.roseus的尖孢镰刀菌,据报道在体外产生长春碱和长春新碱。为了检测这两种不同生物之间可能的合作,应用杀菌剂抑制幼苗中的内生真菌,然后通过1HNMR和HPLC分析测量代谢组。结果表明,内生真菌不直接参与生物碱的生物合成。用杀真菌剂处理影响玫瑰C的初级和次级代谢。全身性杀真菌剂ProntoPlus和Folicur引起了马根素和secologanin水平的增加。相比之下,对照样品中卡塔嘌呤和文多啉的含量较高。这意味着杀真菌剂处理引起植物次生代谢的变化。
    The presence of endophytes in plants is undeniable, but how significant their involvement is in the host plant biosynthetic pathways is still unclear. The results reported from fungicide treatments in plants varied. Fungicide treatment in Taxus was found to decrease the taxol content. In Ipomoea asarifolia, Pronto Plus and Folicur treatments coincided with the disappearance of ergot alkaloids from the plant. In Narcissus pseudonarcissus cv. Carlton, a mixture of fungicide applications decreased the alkaloids concentration and altered the carbohydrate metabolism. Jacobaea plants treated with Folicur reduced the pyrrolizidine alkaloids content. There have not been any studies into the involvement of endophytic fungi on alkaloids production of Catharanthus roseus until now. Though there is a report on the isolation of the endophytic fungi, Fusarium oxysporum from C. roseus, which was reported to produce vinblastine and vincristine in vitro. To detect possible collaborations between these two different organisms, fungicides were applied to suppress the endophytic fungi in seedlings and then measure the metabolomes by 1HNMR and HPLC analysis. The results indicate that endophytic fungi were not directly involved in alkaloids biosynthesis. Treatment with fungicides influenced both the primary and secondary metabolism of C. roseus. The systemic fungicides Pronto Plus and Folicur caused an increase in loganin and secologanin levels. In contrast, control samples had higher level of catharanthine and vindoline. This means that fungicide treatments cause changes in plant secondary metabolism.
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  • 文章类型: Journal Article
    根据中医理论,肝肾功能异常是卵巢早衰(POF)的重要病因。POF是一种常见的降低妊娠率的妇科疾病。电针(EA)是一种有用的非药物疗法,据称可以调节中药治疗POF的肝肾功能。然而,尚未通过代谢组学参考中医理论充分研究EA治疗POF的潜在机制。因此,我们通过代谢组学研究了EA对POF小鼠肝脏和肾脏代谢产物的影响。通过腹膜内注射顺铂建立POF小鼠。三阴交(SP6)和关元(CV4)均受EA刺激3周。生物样本(包括血清和卵巢,肝脏,和肾脏组织)通过组织病理学评估,分子生物学,和氢-1核磁共振(1HNMR)为基础的代谢组学评估EA的疗效。通过正交偏最小二乘判别分析(OPLS-DA)分析1HNMR数据。结果表明,EA对POF的卵巢功能和月经周期有益。肝脏和肾脏的能量代谢和神经递质代谢均受EA调节。值得注意的是,EA在调节肾脏的能量代谢中起重要作用,EA调节肝脏神经递质相关代谢的效果较好。这些结果表明,EA可以改善卵巢功能,并调节POF引起的肝脏和肾脏的代谢紊乱。因此,我们的研究结果表明,EA疗法,根据肝脏和肾脏的结果,与中医的POF有关,通过代谢组学初步证实。
    As per the theory of traditional Chinese medicine (TCM), the liver and kidney dysfunction are important pathogenies for premature ovarian failure (POF). POF is a common gynecological disease that reduced the pregnancy rate. Electro-acupuncture (EA) is a useful non-pharmaceutical therapy that supposedly regulates the function of the liver and kidney in the treatment of POF with TCM. However, the underlying mechanism of EA in the treatment of POF has not been adequately studied through metabonomics with reference to the theory of TCM. Accordingly, we investigated the effect of EA on the liver and kidney metabolites in POF mice through metabolomics. POF mice were established via intraperitoneal injection of cisplatin. Both Sanyinjiao (SP6) and Guanyuan (CV4) were stimulated by EA for 3 weeks. The biological samples (including the serum and the ovary, liver, and kidney tissues) were evaluated by histopathology, molecular biology, and hydrogen-1 nuclear magnetic resonance (1HNMR)-based metabolomics to assess the efficacy of EA. 1HNMR data were analyzed by the orthogonal partial least squares discriminant analysis (OPLS-DA). The results revealed that EA was beneficial to ovarian function and the menstrual cycle of POF. Both the energy metabolism and neurotransmitter metabolism in the liver and kidney were regulated by EA. Notably, EA played an important role in regulating energy-related metabolism in the kidney, and the better effect of neurotransmitter-related metabolism in the liver was regulated by EA. These findings indicated that the ovarian functions could be improved and the metabolic disorder of the liver and kidney caused by POF could be regulated by EA. Our study results thus suggested that the EA therapy, based on the results for the liver and kidney, were related to POF in TCM, as preliminarily confirmed through metabolomics.
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  • 文章类型: Journal Article
    如今,很多个人,无论是健康还是被诊断患有疾病,倾向于让自己接触各种容易获得的天然产品,希望有利于他们的健康和福祉。传统上,地中海人口不仅在营养方面而且在化妆品中使用橄榄油,包括护肤.在这项研究中,酚类化合物——总共由12种化合物组成,使用1HqNMR光谱和HPLC-DAD分析确定了来自克罗地亚本土品种的特级初榨橄榄油(EVOO)的油(OCAL)和油醚(OCEIN),并在黑色素瘤细胞系中研究了其生物学活性。具有最高OCEIN含量的EVOO在A375黑色素瘤细胞中具有最强的抗癌活性,并且对非癌性角膜细胞系(HaCaT)的毒性作用最小。另一方面,纯OCAL被证明比纯OCEIN更有效和更安全。使用任何EVOO酚类提取物(EVOO-PE)进行后处理可增强治疗前应用的抗癌药物达卡巴嗪(DTIC)的抗癌作用,虽然它们没有损害非癌细胞的生存能力。转移性黑色素瘤A375M细胞系几乎对EVOO-PE本身无反应,以及纯CEIN和OCAL。我们的结果表明,橄榄油和/或其化合物可能对黑色素瘤治疗具有潜在的有益作用。然而,它们的使用可能是有害的或徒劳的,尤其是在健康细胞中,由于应用浓度/组合不足或耐药细胞的存在。
    Nowadays, many individuals, whether healthy or diagnosed with disease, tend to expose themselves to various easily accessible natural products in hopes of benefiting their health and well-being. Mediterranean populations have traditionally used olive oil not only in nutrition but also in cosmetics, including skincare. In this study, the phenolic profile-composed of twelve compounds altogether, including the secoiridoids oleocanthal (OCAL) and oleacein (OCEIN)-of extra virgin olive oil (EVOO) from autochthonous cultivars from Croatia was determined using 1H qNMR spectroscopy and HPLC-DAD analysis, and its biological activity was investigated in melanoma cell lines. The EVOO with the highest OCEIN content had the strongest anti-cancer activity in A375 melanoma cells and the least toxic effect on the non-cancerous keratocyte cell line (HaCaT). On the other hand, pure OCAL was shown to be more effective and safer than pure OCEIN. Post-treatment with any of the EVOO phenolic extracts (EVOO-PEs) enhanced the anti-cancer effect of the anti-cancerous drug dacarbazine (DTIC) applied in pre-treatment, while they did not compromise the viability of non-cancerous cells. The metastatic melanoma A375M cell line was almost unresponsive to the EVOO-PEs themselves, as well as to pure OCEIN and OCAL. Our results demonstrate that olive oils and/or their compounds may have a potentially beneficial effect on melanoma treatment. However, their usage can be detrimental or futile, especially in healthy cells, due to inadequately applied concentrations/combinations or the presence of resistant cells.
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  • 文章类型: Journal Article
    目前的目标是合成具有生物活性的Isatin衍生物。为此,从Isatin底物合成Isatin衍生物的六个(06)化学实体,例如3a-3c和4a-4c。
    借助1H-NMR对纯化合物进行了表征,FT-IR,EIMS光谱技术。在盐水虾生物测定的帮助下,评估了合成的胺3a-3c和腙4a-4c的毒性潜力。
    获得的结果表明,3c对卤虫盐藻具有良好的毒性(LD50=1.03×10-5M)。针对四种革兰氏阴性(E.大肠杆菌铜绿假单胞菌,美国伤寒,S.flexneri)和两个革兰氏阳性(B.subtilis,金黄色葡萄球菌)细菌。化合物3a对两种细菌菌株显示出显著的活性;即铜绿假单胞菌,美国伤寒,化合物3c表现出对铜绿假单胞菌的显著活性。化合物4b对伤寒沙门氏菌的活性最高,显示比标准药物更大的抑制区生长直径(GIZ)。化合物4c对铜绿假单胞菌和伤寒沙门氏菌表现出显著的活性。化合物3a-3c和4a-4c对5个菌株中的3个表现出中等至显著的抗菌活性。只有化合物3c对卤虫盐藻具有良好的毒性(LD50=1.03×10-5M)。化合物3a-3c和4a-4c对六种真菌培养物的抗真菌研究;龙氏T.longfusus,C.白色念珠菌,A.黄花,M.卡尼斯,F.solani,和C.glabrata.所有化合物对一种或多种具有抑制作用的病原体具有活性(10-90%)。化合物3a对犬分枝杆菌表现出显著的抑制作用,即90%,70%对T.longfusus,化合物4b进一步显示出对黄曲霉的显著抑制(90%),因此证明是该系列中最活跃的成员。
    所有化合物都显示出更好的抗菌性,抗真菌和细胞毒活性,这可能为制备具有更高抗菌活性的增强分子提供了基础。
    The current objective was to synthesize biologically active Isatin derivatives. For this purpose, six (06) chemical entities of Isatin derivatives such as 3a-3c and 4a-4c were synthesized from Isatin substrate.
    The pure compounds were characterized with the help of 1H-NMR, FT-IR, EIMS spectroscopic techniques. The synthesized amines 3a-3c and hydrazones 4a-4c were evaluated for their toxicity potential with the help of brine shrimp bioassay.
    The obtained results revealed that 3c exhibited promising toxicity (LD50 = 1.03 × 10-5 M) against Artemia salina. The pure chemical entities such as compounds 3a-3c and 4a-4c were evaluated against four Gram-negative (E. coli, P. aeruginosa, S. typhi, S. flexneri) and two Gram-positive (B. subtilis, S. aureus) bacteriae. The compound 3a displayed significant activity against two bacterial strains; i.e. P. aeruginosa, S. typhi, compound 3c demonstrated significant activity against P. aeruginosa. Compound 4b was the most active against S. typhi, displaying a greater diameter of the growth of inhibition zone (GIZ) than the standard drug. Compound 4c exhibited significant activity against P. aeruginosa and S. typhi. Compounds 3a-3c and 4a-4c exhibited moderate to significant antibacterial activity against three out of five strains. Only Compound 3c revealed promising toxicity (LD50 = 1.03 × 10-5 M) against Artemia salina. Antifungal studies of the compounds 3a-3c and 4a-4c against six fungal cultures; T. longifusus, C. albicans, A. flavus, M. canis, F. solani, and C. glabrata. All the compounds were active against one or more pathogens having inhibition (10- 90 %). Compound 3a exhibited significant inhibition i.e. 90 % against M. canis, 70 % against T. longifusus, compound 4b further displayed significant inhibition (90 %) against A. flavus and thus proved to be the most active member of the series.
    All compounds showed better antibacterial, antifungal and cytotoxic activities, which may provide a ground to prepare enhanced molecules with much higher antibacterial activities.
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  • 文章类型: Journal Article
    尽管氧化石墨烯(GO)纳米片在不同领域被广泛使用,它们的毒性机制仍然相对未知。基于NMR的代谢组学用于研究GO纳米片在小鼠中的体内时间和剂量依赖性毒性。在四个不同的时间间隔(包括注射0-后的24和72小时以及7和21天)中来自小鼠的60份血清样品,1-,和10-mg/kgb.w.基于每个样品的1HNMR光谱和多变量方法进行分析。与对照组相比,在GO纳米片处理的小鼠组中鉴定出12种改变的代谢物。这些代谢物参与类固醇激素生物合成和类固醇生物合成途径。可以看出,时间因素比剂量因素更重要,并且各组在时间方向上分开,完全。我们发现GO纳米片具有毒性并且可以影响类固醇激素。然而,这项研究表明,在21天后,治疗组无论其GO纳米片剂量如何都非常接近对照组。这意味着在一步暴露于GO纳米片的过程中,其毒性在21天后减弱。
    Although graphene oxide (GO) nanosheets are widely used in different fields, the mechanism of their toxicity remains relatively unknown. NMR-based metabolomics was used to study in vivo time and dose-dependent toxicity of GO nanosheets in mice. Sixty serum samples from mice in four different time intervals including 24 and 72 h and 7 and 21 days after injection of 0-, 1-, and 10-mg/kg b.w. were analyzed based on 1 HNMR spectra of each sample and multivariate methods. In comparison with the control group, 12 changed metabolites were identified in GO nanosheet-treated mice groups. These metabolites are involved in steroid hormone biosynthesis and steroid biosynthesis pathways. It was seen that the time factor is more important than the dose factor and the groups were separated in a time direction, completely. We found that GO nanosheets has toxicity and can affect steroidal hormones. However, this study shows that after 21 days, the treated groups regardless of their GO nanosheet dose are very close to the control group. This means that in one step exposure to GO nanosheets, their toxicity diminished after 21 days.
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  • 文章类型: Journal Article
    UNASSIGNED: Malaria is an important parasitic disease with high morbidity and mortality in tropical areas. Resistance to most antimalarial drugs has encouraged the development of new drugs including natural products. Venom is a complex mixture of active pharmaceutical ingredients. The purpose of this study was to investigate the antimalarial activity of purified fractions of Naja naja oxiana.
    UNASSIGNED: Lyophilized venom was purified with a Sephacryl S-200 HR column and the fractions lyophilized and inhibitory concentration 50% against Plasmodium falciparum 3D7 in vitro obtained. The 4th fraction was run on a Mono Q column, and activity against P. falciparum was detected by lactate dehydrogenase assay and purity by SDS PAGE. Large scale culture of the parasite was carried out with and without the active fraction on the ring stage for 48 hr. The parasites were collected and lyophilized and analyzed by 1HNMR. Chemometrics studies were performed using MATLAB, differentiating metabolites were identified by Human Metabolic Database, and metabolic pathways by the Metaboanalyst online package.
    UNASSIGNED: The active fraction from the ion exchange column had a 50% inhibitory concentration of 0.026 µg/ml on P. falciparum in vitro (P<0.001) with molecular weight of 63 kDa by SDS-PAGE and no hemolytic activity. Metabolomics studies on the two groups with and without the fraction identified 5 differentiating metabolites and a number of related pathways.
    UNASSIGNED: The metabolites were succinic acid, l-glutamic acid, pyruvic acid, cholesterol, and NAD. The changes in the Krebs cycle and metabolism pathways of nicotinamide and pyruvate were noticeable.
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  • 文章类型: Journal Article
    Dengue is one of the major public health problems in the world, affecting more than fifty million cases in tropical and subtropical region every year. The metabolome, as pathophysiological end-points, provide significant understanding of the mechanism and progression of dengue pathogenesis via changes in the metabolite profile of infected patients. Recent developments in diagnostic technologies provide metabolomics for the early detection of infectious diseases.
    The mid-stream urine was collected from 96 patients diagnosed with dengue fever at Penang General Hospital (PGH) and 50 healthy volunteers. Urine samples were analyzed with proton nuclear magnetic resonance (1H NMR) spectroscopy, followed by chemometric multivariate analysis. NMR signals highlighted in the orthogonal partial least square-discriminant analysis (OPLS-DA) S-plots were selected and identified using Human Metabolome Database (HMDB) and Chenomx Profiler. A highly predictive model was constructed from urine profile of dengue infected patients versus healthy individuals with the total R2Y (cum) value 0.935, and the total Q2Y (cum) value 0.832.
    Data showed that dengue infection is related to amino acid metabolism, tricarboxylic acid intermediates cycle and β-oxidation of fatty acids. Distinct variations in certain metabolites were recorded in infected patients including amino acids, various organic acids, betaine, valerylglycine, myo-inositol and glycine.
    Metabolomics approach provides essential insight into host metabolic disturbances following dengue infection.
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