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Scherner M, Reinhardt S, Wacker M, Weber C, Eghbalzadeh K, Klemm D, Maul A, Sterner-Kock A, Wahlers T, Wippermann J. Tissue Engineered Blood Vessels of Bacterial Nanocellulose: Impact of Surface Modification on Patency and Cell Immigration. Thorac Cardiovasc Surg 2017. [DOI: 10.1055/s-0037-1598738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Bittrich HJ, Klemm D, Stephan D. Die freie Exzeßenthalpie der binären Systeme von Cyclohexylamin und Chlorcyclohexan mit Benzol, Cyclohexan und Methylcyclohexan. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-1975-25658] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Kauer E, Klemm D, Körnig D, Mörke K, Stephan D, Bittrich HJ. Exzeßvolumina binärer Systeme von Naphthenen. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-1973-25211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Klemm E, Klemm D, Kleinschmidt J, Graneß A. Untersuchungen zum Substituenteneinfluß auf die Lebensdauer der Polymethin-Farbform photochromer Dinitrobenzylpyridine. Z PHYS CHEM 2017. [DOI: 10.1515/zpch-1981-26278] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Wacker M, Klemm D, Scherner M, Weber C, Eghbalzadeh K, Reinhardt S, Wahlers T, Petzold-Welcke K, Kramer F, Wippermann J. Further Insights into Tissue Engineered Small Diameter Vascular Grafts: Impact Of Surface Modification on Patency and In Vivo Compatibility. Eur J Vasc Endovasc Surg 2016. [DOI: 10.1016/j.ejvs.2016.07.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Scherner M, Reutter S, Klemm D, Sterner-Kock A, Choi YH, Wahlers T, Wippermann J. In vivo application of tissue-engineered blood vessels of bacterial cellulose as small arterial substitutes: Proof of concept. Thorac Cardiovasc Surg 2012. [DOI: 10.1055/s-0031-1297854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Abou-Ras D, Caballero R, Fischer CH, Kaufmann CA, Lauermann I, Mainz R, Mönig H, Schöpke A, Stephan C, Streeck C, Schorr S, Eicke A, Döbeli M, Gade B, Hinrichs J, Nunney T, Dijkstra H, Hoffmann V, Klemm D, Efimova V, Bergmaier A, Dollinger G, Wirth T, Unger W, Rockett AA, Perez-Rodriguez A, Alvarez-Garcia J, Izquierdo-Roca V, Schmid T, Choi PP, Müller M, Bertram F, Christen J, Khatri H, Collins RW, Marsillac S, Kötschau I. Comprehensive comparison of various techniques for the analysis of elemental distributions in thin films. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2011; 17:728-751. [PMID: 21906418 DOI: 10.1017/s1431927611000523] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.
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Hessler N, Kralisch D, Erdmann R, Schmidt W, Klemm D. Das HoLiR-Konzept zur Gewinnung bakteriell synthetisierter Nanocellulose. CHEM-ING-TECH 2010. [DOI: 10.1002/cite.201050119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Lang N, Sigler M, Merkel E, Fuchs F, Schumann D, Klemm D, Kramer F, Meyer A, Thalmann R, Lehner A, Freudenthal F, Netz H, Kozlik-Feldmann R. Evaluation of bacterial cellulose as a new patch material for closure of muscular ventricular septal defects. Thorac Cardiovasc Surg 2010. [DOI: 10.1055/s-0029-1246848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Takeda K, Okamoto M, de Langhe S, Dill E, Armstrong M, Reisdorf N, Irwin D, Koster M, Wilder J, Stenmark KR, West J, Klemm D, Gelfand EW, Nozik-Grayck E, Majka SM. Peroxisome proliferator-activated receptor-g agonist treatment increases septation and angiogenesis and decreases airway hyperresponsiveness in a model of experimental neonatal chronic lung disease. Anat Rec (Hoboken) 2009; 292:1045-61. [PMID: 19484746 DOI: 10.1002/ar.20921] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chronic lung disease (CLD) affects premature newborns requiring supplemental oxygen and results in impaired lung development and subsequent airway hyperreactivity. We hypothesized that the maintenance of peroxisome proliferator-activated receptor gamma (PPARgamma) signaling is important for normal lung morphogenesis and treatment with PPARgamma agonists could protect against CLD and airway hyperreactivity (AHR) following chronic hyperoxic exposure. This was tested in an established hyperoxic murine model of experimental CLD. Newborn mice and mothers were exposed to room air (RA) or moderate hyperoxia (70% oxygen) for 10 days and fed a standard diet or chow impregnated with the PPARgamma agonist rosiglitazone (ROSI) for the duration of study. Following hyperoxic exposure (HE) animals were returned to RA until postnatal day (P) 13 or P41. The accumulation of ROSI in neonatal and adult tissue was confirmed by mass spectrometry. Analyses of body weight and lung histology were performed on P13 and P41 to localize and quantitate PPARgamma expression, determine alveolar and microvessel density, proliferation and alpha-smooth muscle actin (alpha-SMA) levels as a measure of myofibroblast differentiation. Microarray analyses were conducted on P13 to examine transcriptional changes in whole lung. Pulmonary function and airway responsiveness were analyzed at P55. ROSI treatment during HE preserved septation and vascular density. Key array results revealed ontogeny groups differentially affected by hyperoxia including cell cycle, angiogenesis, matrix, and muscle differentiation/contraction. These results were further confirmed by histological evaluation of myofibroblast and collagen accumulation. Late AHR to methacholine was present in mice following HE and attenuated with ROSI treatment. These findings suggest that rosiglitazone maintains downstream PPARgamma effects and may be beneficial in the prevention of severe CLD with AHR.
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Klemm D, Pfannenstiel P, Weißleder H, Hoffmann G. Auswirkungen der endolymphatischen131J-Therapie auf Proteine und zelluläre Bestandteile des menschlichen Blutes. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1228493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Wippermann J, Schumann D, Klemm D, Albes JM, Wittwer T, Strauch J, Wahlers T. Preliminary results of small arterial substitutes performed with a new cylindrical biomaterial composed of bacterial cellulose. Thorac Cardiovasc Surg 2008. [DOI: 10.1055/s-2008-1037755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Irwin D, Helm K, Campbell N, Imamura M, Fagan K, Harral J, Carr M, Young KA, Klemm D, Gebb S, Dempsey EC, West J, Majka S. Neonatal lung side population cells demonstrate endothelial potential and are altered in response to hyperoxia-induced lung simplification. Am J Physiol Lung Cell Mol Physiol 2007; 293:L941-51. [PMID: 17693487 DOI: 10.1152/ajplung.00054.2007] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lung side population (SP) cells are resident lung precursor cells with both epithelial and mesenchymal potential that are believed to play a role in normal lung development and repair. Neonatal hyperoxic exposure impairs lung development leading to a long-term decrease in gas exchange surfaces. The hypothesis that lung SP cells are altered during impaired lung development has not been studied. To address this issue, we characterized the endothelial potential of neonatal lung SP and subsets of lung SP from neonatal mice following hyperoxic exposure during room air recovery. Lung SP cells were isolated and sorted on the basis of their capacity to efflux Hoechst 33342. The lung SP was further sorted based on expression of Flk-1 and CD45. In vitro, both CD45pos/Flk-1pos and CD45neg/Flk-1pos bind isolectin B4 and incorporate LDL and form networks in matrigel, indicating that these populations have endothelial cell characteristics. Hyperoxic exposure of neonatal mice resulted in subtle changes in vascular and alveolar density on P13, which persisted with room air recovery to P41. During room air recovery, a decrease in lung SP cells was detected in the hyperoxic-exposed group on postnatal day 13 followed by an increase on day 41. Within this group, the lung SP subpopulation of cells expressing CD45 increased on day 21, 41, and 55. Here, we show that lung SP cells demonstrate endothelial potential and that the population distribution changes in number as well as composition following hyperoxic exposure. The hyperoxia-induced changes in lung SP cells may limit their ability to effectively contribute to tissue morphogenesis during room air recovery.
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Klemm D, Geschwend G. α-Bromo-α-ethoxy-acetic Acid Derivatives as New Alkylating Reagents. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397918608056392] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Becher J, Seidel I, Plass W, Klemm D. Synthesis pathway to carbohydrate-derived salicylidene hydrazides as ligands for oxovanadium complexes. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.03.094] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Klemm D, Klemm E, Schüler K, Hörhold HH. Untersuchungen zum Einfluß der Polymermatrix auf die thermische Rückreaktion von photochromen 2,4-Dinitrobenzylpyridinen. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/prac.19773190415] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Hörhold HH, Klemm D, Klee J. Komplexbildung eines linearen Amin-Epoxid-Polyadduktes mit Bariumrhodanid. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/prac.19803220315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Petzold K, Einfeldt L, Günther W, Stein A, Klemm D. Regioselective functionalization of starch: synthesis and 1H NMR characterization of 6-O-silyl ethers. Biomacromolecules 2002; 2:965-9. [PMID: 11710057 DOI: 10.1021/bm010067u] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A high regioselective 6-O silylation of starch by using thexyldimethylchlorosilane (TDSCl, chlorodimethyl-(2,3-dimethylbut-2-yl)silane) as bulky silylating agent in the reaction system N-methylpyrrolidone (NMP)/ammonia was carried out and investigated. The control of the degree of substitution (DSSi), the control of the regioselectivity, and the control of the reaction pathway are described in detail. After peracetylation of the silyl ethers of starch, the distribution of the silyl and acetyl substituents was characterized not only in the anhydroglucose repeating units (AGU) but also in the nonreducing end groups (NEG) by means of multidimensional 1H NMR techniques. In both cases, the silyl substituents were detected exclusively in the 6-O position, and the acetyl groups in the 2-O and 3-O positions of the AGU and in the 2-O, 3-O, and 4-O positions of the NEG, respectively. The described 6-O-thexyldimethylsilyl (TDS) units are potentially protecting groups of the primary OH position of starches.
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Heggemann S, Schnabelrauch M, Klemm D, Möllmann U, Reissbrodt R, Heinisch L. New artificial siderophores based on a monosaccharide scaffold. Biometals 2001; 14:1-11. [PMID: 11368270 DOI: 10.1023/a:1016689807111] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
New artificial catecholate siderophores with methyl alpha-D-glucopyranoside as scaffold were synthesized. The dihydroxy- or di(acetoxy)benzoyl moieties were attached either directly or via aminopropyl spacer groups, to the carbohydrate scaffold. The siderophore activity of the prepared siderophore analogs was examined by a growth promotion assay using various Gram-negative bacteria and mycobacteria and by the CAS-assay.
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Wegner R, Gottschaldt M, Görls H, Jäger EG, Klemm D. Copper(II) complexes of aminocarbohydrate beta-ketoenaminic ligands: efficient catalysts in catechol oxidation. Chemistry 2001; 7:2143-57. [PMID: 11411987 DOI: 10.1002/1521-3765(20010518)7:10<2143::aid-chem2143>3.0.co;2-d] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Copper(II) complexes of tridentate dianionic beta-ketoenaminic ligands derived from differently functionalized amino-deoxyglucoses were synthesized and characterized with respect to their structural, spectroscopic, and catalytic properties. The (probably dimeric) complex [1,2-O-isopropylidene-6-N-(3-acetyl-2-oxobut-3-enyl)amino-6-deoxyglucofuranoso)copper(II) Cu(3a) was a highly efficient catalyst for the catechol-oxidase-like oxidation of 3,5-di-tert-butylcatechol (dtbc) into 3,5-ditert-butylquinone (dtbq) by molecular oxygen (kcat=2.63s(-1)). In contrast to this magnetically "normal" complex Cu(3a), the analogous dinuclear complex [[Cu(2a)]2], derived from the isomeric amino sugar 5-amino-5-deoxyglucofuranose, forms six-membered chelate rings with the sugar moiety and has very strong antiferromagnetic-coupled copper atoms (resulting in a diamagnetic ground state). It has a rather insignificant activity (kcat < 10(-3)s(-1)). The ligand H2 1a, derived from a (protected) 6-amino-6-deoxyglucopyranose, forms a trinuclear complex [[Cu(1a)]]2.Cu(OAc)2] in which two basic formula units are bridged by one copper acetate. This compound and the complex derived from an (isomeric) aminodeoxyglucopyranose ([Cu(4a)]: kcat approximately equals 0.03 s(-1)) show moderate activity. All complexes with a peripheral ethoxycarbonyl group instead of the acetyl substituent R2, Cu(1b)-Cu(3b) and Cu(4c), are inactive. The complexes derived from 2-hydroxocyclohexylamine, Cu(5a) and Cu(5c), which were used as models of the active complex Cu(3a), have the typical "cubane-like" tetranuclear structure known from many copper complexes with derivatives of saturated 2-aminoalcohols. They are inactive with respect to the activation of dioxygen.
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Einfeldt J, Kwasniewski A, Klemm D, Dicke R, Einfeldt L. Analysis of side group motion in O -acetyl-starch using regioselective 2- O -acetyl-starches by means of dielectric spectroscopy. POLYMER 2000. [DOI: 10.1016/s0032-3861(00)00305-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tiller J, Berlin P, Klemm D. Novel matrices for biosensor applications by structural design of redox-chromogenic aminocellulose esters. J Appl Polym Sci 2000. [DOI: 10.1002/(sici)1097-4628(20000214)75:7<904::aid-app7>3.0.co;2-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Tiller J, Berlin P, Klemm D. A novel efficient enzyme-immobilization reaction on NH2 polymers by means of L-ascorbic acid. Biotechnol Appl Biochem 1999; 30:155-62. [PMID: 10512795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A new enzyme-immobilization reaction by means of L-ascorbic acid (ASA) is described using NH(2) polymers based on cellulose or poly(vinyl alcohol) with the example of oxidoreductase enzymes. In this way, enzyme proteins such as glucose oxidase (GOD), glutamate oxidase, lactate oxidase, urate oxidase and peroxidase can be covalently fixed with a high surface loading to ultrathin and transparent NH(2)-polymer films if their surfaces are previously treated with an ASA solution, in, for example, N,N-dimethyl acetamide, DMSO or methanol. ASA then obviously reacts like a diketo compound with amino groups of the NH(2)-polymer film and enzyme protein, forming dehydroascorbic acid derivatives with neighbouring Schiff's-base structures. In a subsequent fragmentation reaction, the latter presumably form stable oxalic acid diamide derivatives as coupling structures between enzyme protein and NH(2)-polymer film, as suggested by results from investigations of the ASA reaction with n-butylamine. The immobilized enzymes can be stored at 4 degrees C in bidistilled water for at least 1 month without becoming detached from the NH(2)-polymer film and without diminished enzyme activity. The apparent K(m) values of the immobilized enzymes are in part clearly smaller than those of the dissolved enzymes or those found in other immobilization processes such as the diazo coupling or the bifunctional glutardialdehyde reaction. For example, the K(m) value of the immobilized GOD with different NH(2) polymers as the matrix structure is smaller by a factor of approx. 20 than that of the dissolved enzyme.
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Klemm D, Moretti V, Vanzo L. Erratum: Rotating topological black holes [Phys. Rev. D 57, 6127 (1998)]. Int J Clin Exp Med 1999. [DOI: 10.1103/physrevd.60.109902] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Liebert T, Klemm D. A new soluble and hydrolytically cleavable intermediate in cellulose functionalization: cellulose dichloroacetate (CDCA). ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1521-4044(199802)49:2/3<124::aid-apol124>3.0.co;2-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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