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Hadjiloizou N, Davies J, Francis D, Baksi A, Parker K, Hughes A, Mayet J. 05.01 CAN WAVE INTENSITY HELP EXPLAIN THE DIFFERENT VELOCITY FLOW PROFILES IN THE CORONARY ARTERIES? Artery Res 2007. [DOI: 10.1016/j.artres.2007.07.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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77
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Davies J, Aguado-Sierra J, Francis D, Hughes A, Parker K, Mayet J. 09.04 A UNIFYING EXPLANATION OF THE AORTIC PULSE WAVEFORM IN HUMANS. Artery Res 2007. [DOI: 10.1016/s1872-9312(07)70018-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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78
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Davies J, Malaweera A, Hadjiloizou N, Parker K, Aguado-Sierra J, Mayet J, Francis D, Hughes A. P.101PULSATILE ARTERIAL PRESSURE IS PREDOMINANTLY DETERMINED BY THE CENTRAL RESERVOIR, WHICH CAN BE DETERMINED NON-INVASIVELY FROM PERIPHERAL MEASUREMENT SITES. Artery Res 2007. [DOI: 10.1016/j.artres.2007.07.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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79
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Davies J, Hadjiloizou N, Aguado-Sierra J, Hughes A, Parker K, Mayet J. P.017 THE ROLE OF THE CORONARY MICROCIRCULATION IN DETERMINING BLOOD FLOW. Artery Res 2007. [DOI: 10.1016/s1872-9312(07)70040-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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80
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Hughes AD, Coady E, Raynor S, Mayet J, Wright AR, Shore AC, Kooner JS, Thom SAM, Chaturvedi N. Reduced endothelial progenitor cells in European and South Asian men with atherosclerosis. Eur J Clin Invest 2007; 37:35-41. [PMID: 17181565 PMCID: PMC1869046 DOI: 10.1111/j.1365-2362.2007.01743.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Circulating endothelial progenitor cells (EPCs) play a role in the repair and regeneration of the endothelium and may represent a novel cardiovascular risk factor. South Asian subjects have an increased risk of cardiovascular disease which is not fully explained by known risk factors. This study examined associations of EPCs with atherosclerosis and possible ethnic differences in EPCs. MATERIALS AND METHODS A population sample of 58 European and South Asian adult men was enriched with the recruitment of an additional 59 European and South Asian men with known coronary disease. The coronary artery calcification score was measured by multi-slice computerized tomography (CT), carotid and femoral intima-media thickness (IMT), and femoral plaques were measured by ultrasound. The subjects were further subdivided into three categories of coronary artery disease on the basis of coronary artery calcification score and clinical history. Total EPCs and non-senescent EPCs (ns-EPCs) were quantified after 5 days cell culture and the number of late outgrowth colonies was measured over a 6-week test period. Circulating CD34+ haematopoietic precursor cells were measured by flow cytometry. RESULTS Individuals with femoral plaques had reduced total and ns-EPCs. The number of ns-EPCs were reduced in individuals with the most coronary atheroma and were inversely related to the coronary calcification score and femoral IMT. These relationships persisted after multivariate adjustment for other risk factors. The numbers of late outgrowth colonies or circulating CD34+ cells were unrelated to the presence of atherosclerosis. There were no differences in the number of EPCs between European and South Asian subjects. CONCLUSION The number of EPCs are reduced in subjects with atherosclerosis independent of other risk factors. Reduction in EPC numbers may be an independent risk factor for atherosclerosis but does not explain ethnic differences in cardiovascular risk.
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81
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Whinnett ZI, Davies JER, Willson K, Manisty CH, Chow AW, Foale RA, Davies DW, Hughes AD, Mayet J, Francis DP. Haemodynamic effects of changes in atrioventricular and interventricular delay in cardiac resynchronisation therapy show a consistent pattern: analysis of shape, magnitude and relative importance of atrioventricular and interventricular delay. Heart 2006; 92:1628-34. [PMID: 16709698 PMCID: PMC1861257 DOI: 10.1136/hrt.2005.080721] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE To assess the haemodynamic effect of simultaneously adjusting atrioventricular (AV) and interventricular (VV) delays. METHOD 35 different combinations of AV and VV delay were tested by using digital photoplethysmography (Finometer) with repeated alternations to measure relative change in systolic blood pressure (SBP(rel)) in 15 patients with cardiac resynchronisation devices for heart failure. RESULTS Changing AV delay had a larger effect than changing VV delay (range of SBP(rel) 21 v 4.2 mm Hg, p < 0.001). Each had a curvilinear effect. The curve of response to AV delay fitted extremely closely to a parabola (average R2 = 0.99, average residual variance 0.8 mm Hg2). The response to VV delay was significantly less curved (quadratic coefficient 67 v 1194 mm Hg/s2, p = 0.003) and therefore, although the residual variance was equally small (0.8 mm Hg2), the R2 value was 0.7. Reproducibility at two months was good, with the SD of the difference between two measurements of SBP(rel) being 2.5 mm Hg for AV delay (2% of mean systolic blood pressure) and 1.5 mm Hg for VV delay (1% of mean systolic blood pressure). CONCLUSIONS Changing AV and VV delays results in a curvilinear acute blood pressure response. This shape fits very closely to a parabola, which may be valuable information in developing a streamlined clinical protocol. VV delay adjustment provides an additional, albeit smaller, haemodynamic benefit to AV optimisation.
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82
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Tillin T, Dhutia H, Chambers J, Malik I, Coady E, Mayet J, Wright A, Kooner J, Chaturvedi N, Hughes A. Mo-P1:155 Southh Asians have narrower coronary arteries and different remodelling responses to disease compared to white Europeans. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)80289-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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83
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Tillin T, Dhutia H, Chambers J, Malik I, Coady E, Mayet J, Wright A, Kooner J, Chaturvedi N, Hughes A. Mo-P1:156 British South Asian men have more adverse plaque morphology despite equivalent atherosclerotic burden to white Europeans. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)80290-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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84
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Aguado-Sierra J, Davies J, Francis D, Whinnett Z, Manisty C, Willson K, Foale R, Malik I, Hughes A, Mayet J, Parker K. Coronary haemodynamics in humans using wave intensity analysis. J Biomech 2006. [DOI: 10.1016/s0021-9290(06)85552-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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85
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Whinnett Z, Davies J, Willson K, Chow A, Foale R, Davies D, Hughes A, Francis D, Mayet J. 752 Reproducibility of non-invasive haemodynamic optimisation of atrioventricular delay in cardiac resynchronisation therapy. Europace 2005. [DOI: 10.1016/eupace/7.supplement_1.169-b] [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] Open
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86
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Whinnett ZI, Davies JER, Lane RE, Francis DP, Mayet J. Echocardiographic methods for selecting patients suitable for biventricular pacing therapy. Minerva Cardioangiol 2005; 53:211-20. [PMID: 16003255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The large outcome studies of biventricular pacing to date have selected patients using electrocardiogram criteria (prolonged QRS and left bundle branch block morphology). However, 20-30% of patients do not appear to respond clinically, and as a result there has been much interest in developing more specific methods of detecting mechanical dyssynchrony. A number of different echocardiographic techniques have been developed which appear to offer greater sensitivity and specificity than ECG in selecting these patients. This paper reviews the most promising of the echocardiographic techniques and gives guidance for the clinical use of echocardiography in selecting patients for biventricular pacing.
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87
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Senior R, Monaghan M, Becher H, Mayet J, Nihoyannopoulos P. Stress echocardiography for the diagnosis and risk stratification of patients with suspected or known coronary artery disease: a critical appraisal. Supported by the British Society of Echocardiography. Heart 2005; 91:427-36. [PMID: 15772187 PMCID: PMC1768798 DOI: 10.1136/hrt.2004.044396] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Stress echocardiography today has matured into a robust and reliable technique not only for the diagnosis of suspected coronary artery disease (CAD) but also for the accurate risk stratification of patients with suspected and established CAD. This is mainly because of rapid advances in image acquisition, digital display, and the development of harmonic and contrast imaging. Stress echocardiography today is also utilised in patients with heart failure both for assessing the cause of heart failure and determining the extent of hibernating myocardium. With advances in myocardial perfusion imaging, stress echocardiography now allows simultaneous assessment of myocardial function and perfusion. Tissue Doppler imaging allows quantitation of wall motion. Ready availability and reliability makes stress echocardiography a cost effective technique for the assessment of CAD.
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Lane RE, Chow AWC, Chin D, Mayet J. Selection and optimisation of biventricular pacing: the role of echocardiography. Heart 2005; 90 Suppl 6:vi10-6. [PMID: 15564419 PMCID: PMC1876331 DOI: 10.1136/hrt.2004.043000] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The quantification of ventricular dyssynchrony is a key factor in identifying patients with severe heart failure who may benefit from cardiac resynchronisation with biventricular pacing (BVP). Echocardiographic techniques appear to offer superior sensitivity and specificity than the ECG in selecting these patients. This paper reviews the scope of current echocardiographic techniques for guiding both patient selection and optimisation of device programming following implantation.
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89
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Abstract
Nurse led cardioversion services have achieved significant reductions in both cost and waiting time. However, the question of safety of the procedure raises several areas of concern.
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90
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Kapur A, Malik IS, Bagger JP, Anderson JR, Kooner JS, Thomas M, Punjabi P, Mayet J, Millane T, Goedicke J, Jamrozik K, de Belder MA, Hall RJ, Beatt KJ. The Coronary Artery Revascularisation in Diabetes (CARDia) trial: background, aims, and design. Am Heart J 2005; 149:13-9. [PMID: 15660030 DOI: 10.1016/j.ahj.2004.07.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Patients with diabetes have an increased incidence and severity of ischemic heart disease, which leads to an increased requirement for coronary revascularization. Comparative information regarding mode of revascularization--coronary artery bypass graft surgery surgery (CABG) or percutaneous coronary intervention (PCI)--is limited, mainly confined to a subanalysis of the Bypass Angioplasty Revascularization (BARI) trial, suggesting a mortality benefit of CABG over PCI. No prospective trial has specifically compared these modes of revascularization in patients with diabetes. OBJECTIVE The Coronary Artery Revascularisation in Diabetes (CARDia) trial is designed to address the hypothesis that optimal PCI is not inferior to modern CABG as a revascularization strategy for diabetics with multivessel or complex single-vessel coronary disease. The primary end point is a composite of death, nonfatal myocardial infarction, and cerebrovascular accident at 1 year. METHOD A total of 600 patients with diabetes are to be randomized to either PCI or CABG, with few protocol restrictions on operative techniques or use of new technology. This gives a power of 80% to detect non-inferiority of PCI assuming that the PCI 1-year event rate is 9%. A cardiac surgeon and a cardiologist must agree that a patient is suitable for revascularization by either technique prior to recruitment into the study. Twenty-one centers in the United Kingdom and Ireland are recruiting patients. Data on cost effectiveness, quality of life, and neurocognitive function are being collected. Long-term (3-5 year) follow-up data will also be collected.
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91
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Wong T, Mayet J, Casula RP. Minimal invasive direct revascularisation of the left anterior descending artery using a novel magnetic vascular anastomotic device. BRITISH HEART JOURNAL 2004; 90:632. [PMID: 15145863 PMCID: PMC1768292 DOI: 10.1136/hrt.2003.023929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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92
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Senior R, Galasko G, McMurray JV, Mayet J. Screening for left ventricular dysfunction in the community: role of hand held echocardiography and brain natriuretic peptides. BRITISH HEART JOURNAL 2003; 89 Suppl 3:iii24-8. [PMID: 14594872 PMCID: PMC1876302 DOI: 10.1136/heart.89.suppl_3.iii24] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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93
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Abstract
Providing anaesthetic cover for DC cardioversion can sometimes prove a challenge for the cardiologist, with potentially disastrous consequences for the patient
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94
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El Gendi H, Ismail T, Charalampos K, Mayet J. Anticoagulation for cardioversion of atrial fibrillation. Minerva Cardioangiol 2002; 50:43-52. [PMID: 11830718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The cardioversion of chronic atrial fibrillation to sinus rhythm carries a thromboembolic risk of 1.5-6%. These events occasionally occur at the time of cardioversion, but more often happen hours or days later. These strokes and other embolic events may occur even where atrial thrombus has been excluded before cardioversion and it has become apparent that, although atrial electrical activity may be restored by cardioversion, normal mechanical atrial function may take longer to recover. Numerous studies have addressed the role of anticoagulation following cardioversion in patients with atrial fibrillation, however, the mechanism of embolic complications as well as the justification of a standard anticoagulation therapy are not fully established. In this review we will try to present an overview of the mechanisms of thrombosis following cardioversion and give an insight into current anticoagulation strategies.
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96
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Stanton AV, Chapman JN, Mayet J, Sever PS, Poulter NR, Hughes AD, Thom SA. Effects of blood pressure lowering with amlodipine or lisinopril on vascular structure of the common carotid artery. Clin Sci (Lond) 2001; 101:455-64. [PMID: 11672450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Increased intima-media thickness of the common carotid artery predicts increased risk of myocardial infarction and stroke. Preliminary evidence suggests that a decrease in blood pressure (BP) is associated with diminished wall thickness. It is not known if all classes of anti-hypertensive agents have similar protective effects. In this double-blind parallel-group clinical trial, 69 previously untreated patients with hypertension were allocated randomly to 1 year of treatment with either amlodipine (5-10 mg daily) or lisinopril (5-20 mg daily). Doxazosin and bendrofluazide were added if required to achieve BP control. After 12 months of treatment, clinic BP, ambulatory BP and cardiac mass were reduced similarly by the two treatment regimens. Common carotid artery intima-media thickness decreased by 0.048 mm (95% confidence intervals -0.066, -0.031 mm) in the amlodipine-treated group, but decreased by only 0.027 mm (-0.046, -0.007 mm) in the lisinopril-treated group (P<0.05 for difference between treatments). Common carotid artery lumen diameter declined significantly only in patients treated with lisinopril [amlodipine, -0.02 mm (-0.14, 0.10 mm); lisinopril, -0.21 mm (-0.32, -0.11 mm); P<0.02], while intima-media area declined similarly in the two treatment groups [amlodipine -1.32 mm(2) (-1.91, -0.74 mm(2)), lisinopril -1.26 mm(2) (-1.80, -0.72 mm(2)); not significant]. The results confirm that a decrease in BP causes regression of structural changes in the carotid artery in hypertensive patients. The nature of the structural regression differed markedly between the two treatment regimens, in spite of similar decreases in BP. The calcium channel blocker induced greater regression of common carotid artery intima-media thickness than the angiotensin-converting enzyme inhibitor. However, carotid artery wall mass, as indicated by intima-media area, was reduced to a similar extent by the two treatments. It remains to be established whether such differences confer a prognostic advantage.
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97
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98
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Stanton A, Fitzgerald D, Hughes A, Mayet J, O'Brien E, Poulter NR, Sever PS, Shields D, Thom S. An intensive phenotyping study to enable the future examination of genetic influences on hypertension-associated cardiovascular disease. J Hum Hypertens 2001; 15 Suppl 1:S13-8. [PMID: 11685902 DOI: 10.1038/sj.jhh.1001089] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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99
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Francis D, Lane R, Mayet J, Foale RA, Thom S, Peters NS. Microvolt T wave alternans in patients with hypertension and left ventricular hypertrophy. J Hum Hypertens 2001; 15 Suppl 1:S95-6. [PMID: 11685922 DOI: 10.1038/sj.jhh.1001254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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100
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El Gendi H, Wasan B, Mayet J. Anticoagulation in atrial fibrillation. Lancet 2001; 358:150-1. [PMID: 11469239 DOI: 10.1016/s0140-6736(01)05356-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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