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1.
J Sep Sci ; 2020 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-32386337

RESUMO

There are numerous papers published for geographical discrimination of tea. However, few research works focused on the authentication and traceability of Westlake Longjing green tea from the first- and second-grade producing regions because the tea trees are planted in a limited growing zone with identical cultivate condition. In this work, a comprehensive analytical strategy was proposed by ultrahigh performance liquid chromatography-quadrupole time-of-flight mass spectrometry-based untargeted metabolomics coupled with chemometrics. The automatic untargeted data analysis strategy was introduced to screen metabolites that expressed significantly among different regions. Chromatographic features of metabolites can be automatically and efficiently extracted and registered. Meanwhile, those that were valuable for geographical origin discrimination were screened based on statistical analysis and contents in samples. Metabolite identification was performed based on high-resolution mass values and MS/MS spectra of screened peaks. Twenty metabolites were identified, based on which the two-way encoding partial least squares discrimination analysis was built for geographical origin prediction. Monte Caro simulation results indicated that prediction accuracy was up to 99%. Our strategy can be applicable for practical applications in the quality control of Westlake Longjing green tea. This article is protected by copyright. All rights reserved.

2.
J Org Chem ; 85(2): 622-632, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31799847

RESUMO

An efficient Pd-catalyzed arylation of alkylpyridine based on the pyridinium activation strategy has been developed for synthesis of mixed aryl alkylpyridines. It was found that (1) the N-methyl group in the pyridinium salts acted as a transient activator and could be automatically departed after the reaction, (2) CuBr was an indispensable additive for achieving the C6-selective arylation, (3) the α-branched alkyl chain on the alkylpyridine greatly increased the yield of the product. Deuterium labelling experiment revealed that in the case of the α-branched alkylpyridine, the presence of CuBr completely inhibited the H/D exchange at the benzylic position and thus enabled the selective arylation at the C6 position. This protocol demonstrates a broad substrate scope, and with respect to both the aryl iodides and the α-branched alkylpyridine, the desired mixed aryl alkylpyridines were obtained in generally good to excellent yields.

3.
J Chromatogr A ; 1616: 460787, 2020 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31864723

RESUMO

Automatic data analysis for gas chromatography-mass spectrometry (GC-MS) is a challenging task in untargeted metabolomics. In this work, we provide a novel comprehensive data analysis strategy for GC-MS-based untargeted metabolomics (autoGCMSDataAnal) by developing a new automatic strategy for performing TIC peak detection and resolution and proposing a novel time-shift correction and component registration algorithm. autoGCMSDataAnal uses original acquired GC-MS datafiles as input to automatically perform TIC peak detection, component resolution, time-shift correction and component registration, statistical analysis, and compound identification. We utilize standards and complex plant samples to comprehensively investigate the performance of autoGCMSDataAnal. The results suggest that the developed strategy is comparable with several state-of-the-art methods that are widely used in GC-MS-based untargeted metabolomics. Based on the proposed strategy, we develop a user-friendly MATLAB GUI for users who are unfamiliar with programming languages to facilitate their routine analysis, which can be freely downloaded at: http://software.tobaccodb.org/software/autogcmsdataanal.

4.
Technol Cancer Res Treat ; 18: 1533033819892263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31818225

RESUMO

Non-small cell lung cancer is the most common malignant tumor in the world. Currently, chemotherapy is still the major method for non-small cell lung cancer treatment, but the problem of cancer drug resistance still exists, so we designed 5 different phosphorothioate oligonucleotides to silence key genes in tumor cell development, which could help avoid inducing cancer cell drug resistance. MicroRNAs have been shown to play a crucial role in the pathogenesis and progression of many malignancies, such as breast, colon, lung, and pancreatic cancer. According to the data from the Gene Expression Omnibus database, miR-21 has been reported to be one of the top 20 differentially expressed microRNAs screened using the Morpheus online tool, and miR-21 has been revealed to regulate a series of biological behaviors in cancer cells, including cell proliferation, migration, invasion, metastasis, and apoptosis. In recent years, gene therapy has emerged as a new therapeutic strategy for cancer treatment. Antisense oligonucleotides have recently been suggested as a novel approach for targeting microRNAs by antisense-based gene silencing. Five phosphorothioate oligonucleotides were designed, synthesized, and screened for anticancer activity. Reverse transcription-polymerase chain reaction was used to detect the relative expression of miR21. Among these 5 sequences, only phosphorothioate oligonucleotide 4 inhibited the proliferation of H1650 cells, and this effect was due to the induction of cancer cell apoptosis by activating the caspase-8 apoptotic pathway. In conclusion, this research confirmed the anticancer activity of phosphorothioate oligonucleotide 4 and revealed the underlying mechanism, which has the potential to be a novel anticancer strategy.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(12): 1198-1202, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31874659

RESUMO

OBJECTIVE: To study the value of serum gamma-glutamyl transpeptidase (GGT) combined with direct bilirubin (DB) in the diagnosis of biliary atresia. METHODS: A total of 667 infants with cholestasis who were hospitalized and treated from July 2010 to December 2018 were enrolled as subjects. According to the results of intraoperative cholangiography and follow-up, they were divided into biliary atresia group with 234 infants and cholestasis group with 433 infants. The two groups were compared in terms of age of onset, sex, and serum levels of total bilirubin (TB), DB, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bile acid (TBA), and GGT. A receiver operating characteristic (ROC) curve analysis was performed for indices with statistical significance, and the area under the ROC curve (AUC) and the optimal cut-off value for diagnosis were calculated. RESULTS: The biliary atresia group had a significantly younger age of onset than the cholestasis group (P<0.001). There were no significant differences in sex, ALT, and AST between the two groups (P>0.05), while the biliary atresia group had significantly higher serum levels of TB, DB, TBA, and GGT than the cholestasis group (P<0.05). GGT combined with DB had the highest AUC of 0.892 (95% confidence interval: 0.868-0.916) in the diagnosis of biliary atresia. At the optimal cut-off values of 324.0 U/L for GGT and 115.1 µmmol/L for DB, GGT combined with DB had a sensitivity of 79.8% and a specificity of 83.2% in the diagnosis of biliary atresia. CONCLUSIONS: GGT combined with DB has high sensitivity and specificity in the diagnosis of biliary atresia and can be used as an effective indicator for diagnosis of biliary atresia in infants.


Assuntos
Atresia Biliar , gama-Glutamiltransferase/sangue , Alanina Transaminase , Aspartato Aminotransferases , Atresia Biliar/diagnóstico , Bilirrubina , Humanos , Lactente
6.
Opt Express ; 27(15): 20910-20927, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510178

RESUMO

Scratches on the surface of optical components have serious impacts on optical system such as imaging quality of lens and/or mirrors in optical imaging systems, light-collecting abilities of laser fusion and solar concentrator systems. The size of the scratches is a key issue for analyzing and assessing the impacts quantitatively. Most of the available testing methods for scratches depend on human visual inspection (HVI) with naked eyes by workers, which leads to low efficiency and accuracy. This paper presents an automatic detecting method for the scratches on optical surface with machine vision inspection (MVI) method. The microscopic dark-field scattering imaging system is used as the front end of the detection system. A dedicated algorithm is designed for non-closing scratch detection. The core merits of this algorithm lies in three folds: 1) automatic processing capabilities, which includes positioning, clustering, and precise estimation of the length of the scratches; 2) high efficiency, which is characterized by a short time interval, i.e., about 0.138 second per binary image with 2724 × 2724 pixels in our experiments; 3) high accuracy, where the error rate of the total length of the scratches detected is less than 5% when compared with the nominal visual measurement result obtained via HVI method. The proposed scratch detecting algorithm can be used for non-destructive testing (NDT) of the glass-like surfaces.

7.
J Anal Methods Chem ; 2019: 2796502, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380141

RESUMO

The feasibility of combining elemental fingerprints and chemical pattern recognition methods for authentication of the geographical origins of a Chinese herb, Gastrodia elata BI. (GE), was studied in this paper. A total of 210 GE samples were collected from 7 different producing areas. The levels of 15 mineral elements in GE, including Zn, Cd, Co, Cr, Cu, Ca, Mg, Mn, Mo, Ni, Pb, Sr, Fe, Na, and K, were determined using inductively coupled plasma mass spectrometry (ICP-MS). Using the autoscaled data of elemental fingerprints and partial least-squares discriminant analysis (PLSDA), two chemometrics strategies for multiclass classifications, One-Versus-Rest (OVR) and One-Versus-One (OVO), were studied and compared in discrimination of GE geographical origins. As a result, OVR-PLSDA and OVO-PLSDA could achieve the classification accuracy of 0.672 and 0.925, respectively. The results indicate that mineral elemental fingerprints coupled with chemometrics can provide a useful alternative method for simultaneous discrimination of multiple GE geographical origins.

8.
J Org Chem ; 84(14): 9151-9160, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31273988

RESUMO

A selective catalytic system for the dehydrogenation of primary alcohols to carboxylic acids using a facial ruthenium complex generated in situ from the [Ru(COD)Cl2]n and a hybrid N-heterocyclic carbene (NHC)-phosphine-phosphine ligand (CPP) has been first reported. The facial coordination model was unveiled by NMR analysis of the reaction mixture. Such a fac-ruthenium catalyst system exhibited high catalytic activity and stability, and a high turnover number of 20 000 could be achieved with catalyst loading as low as 0.002 mol %. The exceedingly high catalyst stability was tentatively attributed to both the anchoring role of NHC and the hemi-lability of phosphines. The catalytic system also features a wide substrate scope. In particular, the facial coordination of CPP ligands was found to be beneficial for sterically hindered alcohols, and ortho-substituted benzylic alcohols and bulky adamantanyl methanol as well as cholesterol were all found to be viable dehydrogenation substrates.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 221: 117212, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31158771

RESUMO

To enhance the power of untargeted detection, a "turn-off" fluorescent probe with double quantum dots (QDs) was developed and coupled with chemometrics for rapid detection of multiple adulterants in an herbal (Rhus chinensis Mill., RCM) honey. The double water-soluble ZnCdSe-CdTe QDs have two separate and strong fluorescent peaks, which can be quenched by honey and extraneous adulterants with varying degrees. Class models of pure RCM honey samples collected from 6 different producing areas (n = 122) were developed using one-class partial least squares (OCPLS). Four extraneous adulterants, including glucose syrup, sucrose syrup, fructose syrup, and glucose-fructose syrup were added to pure honey samples at the levels of 0.5% to 10% (w/w). As a result, the OCPLS model using the second-order derivative (D2) spectra could detect 1.0% (w/w) of different syrups in RCM honey, with a sensitivity of 0.949. The double water-soluble QDs, which can be adjusted for analysis of other water-soluble food samples, has largely extended the capability of traditional fluorescence and will provide a potentially more sensitive and specific analysis method for food frauds.


Assuntos
Corantes Fluorescentes/química , Contaminação de Alimentos/análise , Mel/análise , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Compostos de Cádmio/química , China , Glucose/química , Análise dos Mínimos Quadrados , Modelos Estatísticos , Compostos de Selênio/química , Sensibilidade e Especificidade , Solubilidade , Espectrometria de Fluorescência/estatística & dados numéricos , Sacarose/química , Telúrio/química , Compostos de Zinco/química
10.
J Nat Prod ; 82(2): 221-231, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30702286

RESUMO

Ten new prenylated indole diterpene alkaloids, tolypocladin A-J (1-10), including four chlorinated metabolites, have been isolated from a culture of a mine-soil-derived fungus, Tolypocladium sp. XL115. The structures and absolute configurations of 1-10 were determined by spectroscopic analysis, ECD calculations, and comparison with known compounds. Compounds 1 and 8 displayed significant antimicrobial activities. In addition, compound 1 also showed weak cytotoxic activity against all tested human cancer cell lines and suppressed the growth and viability of the patient-derived HCC cells T1224.

11.
J Org Chem ; 84(4): 2158-2168, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30676029

RESUMO

Herein, an efficient and green method for the selective synthesis of tertiary amines has been developed that involves iridium-catalyzed alkylation of various primary amines with aromatic or aliphatic alcohols. Notably, the catalytic protocol enables this transformation in the absence of additional base and solvent. Furthermore, the alkylation of nitrobenzene with primary alcohol to tertiary amine has also been achieved by the same catalytic system. Deuterium-labeling experiments and a series of control experiments were conducted, and the results suggested that an intermolecular borrowing hydrogen pathway might exist in the alkylation process.

12.
J Chromatogr A ; 1585: 172-181, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30509617

RESUMO

Data analysis for ultra-performance liquid chromatography high-resolution mass spectrometry-based metabolomics is a challenging task. The present work provides an automatic data analysis workflow (AntDAS2) by developing three novel algorithms, as follows: (i) a density-based ion clustering algorithm is designed for extracted-ion chromatogram extraction from high-resolution mass spectrometry; (ii) a new maximal value-based peak detection method is proposed with the aid of automatic baseline correction and instrumental noise estimation; and (iii) the strategy that clusters high-resolution m/z peaks to simultaneously align multiple components by a modified dynamic programing is designed to efficiently correct time-shift problem across samples. Standard compounds and complex datasets are used to study the performance of AntDAS2. AntDAS2 is better than several state-of-the-art methods, namely, XCMS Online, Mzmine2, and MS-DIAL, to identify underlying components and improve pattern recognition capability. Meanwhile, AntDAS2 is more efficient than XCMS Online and Mzmine2. A MATLAB GUI of AntDAS2 is designed for convenient analysis and is available at the following webpage: http://software.tobaccodb.org/software/antdas2.


Assuntos
Cromatografia Líquida de Alta Pressão , Análise de Dados , Espectrometria de Massas , Metabolômica/métodos , Algoritmos , Análise por Conglomerados , Metabolômica/instrumentação , Fluxo de Trabalho
13.
Fitoterapia ; 131: 55-58, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30352295

RESUMO

Two novel sesquiterpenoids with an unprecedented tricyclo[4,4,2,1]hendecane scaffold, namely emericellins A (1) and B (2) representing a new skeleton, were isolated from the liquid cultures of an endophytic fungus Emericella sp. XL 029 associated with the leaves of Panax notoginseng. Their structures and relative configurations were characterized by extensive spectroscopic methods. Compounds 1-2 displayed moderate activities against three fungal strains (Verticillium dahliae Kleb, Helminthosporium maydis, and Botryosphaeria dothidea) and three bacterial strains (Bacillus subtilis, Bacillus cereus and Escherichia coli) with MIC values of 25-50 µg/mL.


Assuntos
Anti-Infecciosos/química , Emericella/química , Panax notoginseng/microbiologia , Sesquiterpenos/química , Anti-Infecciosos/isolamento & purificação , China , Endófitos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Folhas de Planta/microbiologia , Sesquiterpenos/isolamento & purificação
14.
Exp Ther Med ; 16(2): 1493-1498, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30116399

RESUMO

The aim of the present study was to investigate the effects of adjuvant rhubarb on the recovery of patients with heat stroke. A total of 85 patients with heat stroke were randomly assigned to two treatment groups: One group receiving conventional treatment for heat stroke (conventional group) and one group receiving rhubarb supplement in addition to conventional treatment (rhubarb group). Liver and kidney function parameters, Acute Physiology and Chronic Health Evaluation (APACHE) II scores, plasma interleukin-6 (IL-6), procalcitonin (PCT), C-reactive protein (CRP) levels and venous white blood cell count (WBC) were analyzed. The length of stay in the intensive care units (ICUs) and hospital were recorded. Kaplan-Meier curves were drawn to determine the 30-day survival of the patients. The results indicated that rhubarb supplementation significantly reduced the WBC, as well as CRP, PCT and IL-6 levels at treatment days 3-5. Furthermore, rhubarb intake was observed to limit heat stroke-induced damage to liver and kidney function by decreasing the abnormally high levels of plasma aspartate aminotransferase, alanine aminotransferase and creatinine. Finally, patients in the rhubarb group had shorter ICU and hospital stays as well as a lower APACHE II score than those in the conventional group. However, no significant difference in the 30-day mortality rate was observed between the two groups. In conclusion, rhubarb intake provided a significant benefit for patients with heat stroke by inhibiting systemic inflammation and mitigating liver and kidney injury.

15.
Biomed Res Int ; 2018: 1718046, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29682519

RESUMO

High-accuracy alignment of sequences with disease information contributes to disease treatment and prevention. The results of multiple sequence alignment depend on the parameters of the objective function, including gap open penalties (GOP), gap extension penalties (GEP), and substitution matrix (SM). Firstly, the theory parameter formulas relating to GOP, GAP, and SM are inferred, combining unaligned sequence length, number, and identity. Secondly, we tested the rationality of the theory parameter formulas, with experiment on the ClustalW and MAFFT program. In addition, we obtained a group of MAFFT program parameters according to the formulas proposed. The results of all experiments show that the SPS (sum-of-pair score) obtained from theory parameters is better than the SPS obtained from the default parameters of ClustalW and MAFFT. In both theory and practice, our method to determine the parameters is feasible and efficient. These can provide high-accuracy alignment results for precision medicine.


Assuntos
Sequência de Bases/genética , Doença/genética , Genoma/genética , Medicina de Precisão/métodos , Biologia Computacional/métodos , Humanos , Alinhamento de Sequência/métodos , Software
16.
Nat Prod Bioprospect ; 8(2): 71-82, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29488079

RESUMO

E-jiao (Colla Corii Asini, CCA) has been widely used as a healthy food and Chinese medicine. Although authentic CCA is characterized by its typical sweet and neutral fragrance, its aroma components have been rarely investigated. This work investigated the aroma-active components and antioxidant activity of 19 CCAs from different geographical origins. CCA extracts obtained by simultaneous distillation and extraction were analyzed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O) and sensory analysis. The antioxidant activity of CCAs was determined by ABTS and DPPH assays. A total of 65 volatile compounds were identified and quantified by GC-MS and 23 aroma-active compounds were identified by GC-O and aroma extract dilution analysis. The most powerful aroma-active compounds were identified based on the flavor dilution factor and their contents were compared among the 19 CCAs. Principal component analysis of the 23 aroma-active components showed 3 significant clusters. Canonical correlation analysis between antioxidant assays and the 23 aroma-active compounds indicates strong correlation (r = 0.9776, p = 0.0281). Analysis of aroma-active components shows potential for quality evaluation and discrimination of CCAs from different geographical origins.

17.
J Org Chem ; 83(8): 4441-4454, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29595260

RESUMO

The first Pd-catalyzed multicomponent reaction of aryl iodides, alkenyl bromides, and strained alkenes has been developed, which allowed us to synthesize a variety of multisubsituted olefins in yields of 45-96% with excellent stereoselectivity. The configuration of the product was controlled by the configuration of the alkenyl bromides. Moreover, this practical methodology employing readily available substrates was found to be tolerant to a wide range of functional groups. Fifty six examples of highly stereoselective tri- or tetrasubstituted olefins have been successfully synthesized via this methodology. Most of the synthesized tetrasubstituted olefins are good aggregation-induced emission (AIE) luminogens.

18.
J Reprod Dev ; 64(1): 49-55, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29249781

RESUMO

Brusatol, a quassinoid isolated from the fruit of Bruceajavanica, has recently been shown to inhibit nuclear factor erythroid 2-related factor 2 (Nrf2) via Keap1-dependent ubiquitination and proteasomal degradation or protein synthesis. Nrf2 is a transcription factor that regulates the cellular defense response. Most studies have focused on the effects of Nrf2 in tumor development. Here, the critical roles of Nrf2 in mouse early embryonic development were investigated. We found that brusatol treatment at the zygotic stage prevented the early embryo development. Most embryos stayed at the two-cell stage after 5 days of culture (P < 0.05). This effect was associated with the cell cycle arrest, as the mRNA level of CDK1 and cyclin B decreased at the two-cell stage after brusatol treatment. The embryo development potency was partially rescued by the injection of Nrf2 CRISPR activation plasmid. Thus, brusatol inhibited early embryo development by affecting Nrf2-related cell cycle transition from G2 to M phase that is dependent on cyclin B-CDK1 complex.


Assuntos
Ciclo Celular/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Animais , Ciclo Celular/fisiologia , Regulação para Baixo/efeitos dos fármacos , Desenvolvimento Embrionário/fisiologia , Feminino , Camundongos , Extratos Vegetais/farmacologia , Quassinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
19.
Nat Prod Bioprospect ; 7(6): 445-459, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29177644

RESUMO

An HPLC-DAD method combined with second-order calibration based on the alternating trilinear decomposition (ATLD) algorithm with the aid of region selection was developed to simultaneously and quantitatively characterize the synergistic relationships and cumulative excretion of the four bioactive ingredients of Radix Gentianae Macrophyllae in vivo. Although the analytes spectra substantially overlapped with that of the biological matrix, the overlapping profiles between analytes and co-eluting interferences can be successfully separated and accurately quantified by the ATLD method on the basis of the strength of region selection. The proposed approach not only determined the content change but also revealed the synergistic relationships and the cumulative excretion in vivo of the four ingredients in urine and feces samples collected at different excretion time intervals. In addition, several statistical parameters were employed to evaluate the accuracy and precision of the method. Quantitative results were confirmed by HPLC-mass spectrometry. Satisfactory results indicated that the proposed approach can be utilized to investigate the pharmacokinetics of Radix Gentianae Macrophyllae excretion in vivo.

20.
Anal Chem ; 89(20): 11083-11090, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-28922607

RESUMO

High-quality data analysis methodology remains a bottleneck for metabolic profiling analysis based on ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry. The present work aims to address this problem by proposing a novel data analysis strategy wherein (1) chromatographic peaks in the UPLC-QTOF data set are automatically extracted by using an advanced multiscale Gaussian smoothing-based peak extraction strategy; (2) a peak annotation stage is used to cluster fragment ions that belong to the same compound. With the aid of high-resolution mass spectrometer, (3) a time-shift correction across the samples is efficiently performed by a new peak alignment method; (4) components are registered by using a newly developed adaptive network searching algorithm; (5) statistical methods, such as analysis of variance and hierarchical cluster analysis, are then used to identify the underlying marker compounds; finally, (6) compound identification is performed by matching the extracted peak information, involving high-precision m/z and retention time, against our compound library containing more than 500 plant metabolites. A manually designed mixture of 18 compounds is used to evaluate the performance of the method, and all compounds are detected under various concentration levels. The developed method is comprehensively evaluated by an extremely complex plant data set containing more than 2000 components. Results indicate that the performance of the developed method is comparable with the XCMS. The MATLAB GUI code is available from http://software.tobaccodb.org/software/antdas .

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