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Collins JC. Built to last. Interview by Joe Flower. THE HEALTHCARE FORUM JOURNAL 1995; 38:62-8. [PMID: 10144907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Collins JC, Sarfeh IJ. Surgical management of portal hypertension. West J Med 1995; 162:527-35. [PMID: 7618313 PMCID: PMC1022831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Portal hypertension is frequently complicated by upper gastrointestinal tract bleeding and ascites. Hemorrhage from esophageal varices is the most common cause of death from portal hypertension. Medical treatment, including resuscitation, vasoactive drugs, and endoscopic sclerosis, is the preferred initial therapy. Patients with refractory hemorrhage frequently are referred for immediate surgical intervention (usually emergency portacaval shunt). An additional cohort of patients with a history of at least 1 episode of variceal hemorrhage is likely to benefit from elective shunt operations. Shunt operations are classified as total, partial, or selective shunts based on their hemodynamic characteristics. Angiographically created shunts have been introduced recently as an alternative to operative shunts in certain circumstances. Devascularization of the esophagus or splenectomy is done for specific indications. Medically intractable ascites is a separate indication for surgical intervention. Liver transplantation has been advocated for patients whose portal hypertension is a consequence of end-stage liver disease. In the context of an increasingly complex set of treatment options, we present an overview of surgical therapy for complications of portal hypertension.
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Collins JC, Huston J, Pumplin J, Weerts H, Whitmore JJ. Measuring parton densities in the Pomeron. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1995; 51:3182-3196. [PMID: 10018795 DOI: 10.1103/physrevd.51.3182] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Collins JC, Scalise RJ. Renormalization of composite operators in Yang-Mills theories using a general covariant gauge. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 50:4117-4136. [PMID: 10018051 DOI: 10.1103/physrevd.50.4117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Aivazis MA, Collins JC, Olness FI, Tung WK. Leptoproduction of heavy quarks. II. A unified QCD formulation of charged and neutral current processes from fixed-target to collider energies. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 50:3102-3118. [PMID: 10017944 DOI: 10.1103/physrevd.50.3102] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Collins JC, Rypins EB, Sarfeh IJ. Narrow-diameter portacaval shunts for management of variceal bleeding. World J Surg 1994; 18:211-5. [PMID: 8042325 DOI: 10.1007/bf00294403] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Over the past decade, we have developed and refined a method for partial portosystemic shunting for the control of bleeding esophageal varices in alcoholic cirrhotic patients. The narrow-diameter interposition portacaval H-graft using 8 mm polytetrafluoroethylene has been performed in 32 patients at our institution with low operative mortality (6.3%) and nearly complete cessation of variceal bleeding (96.7%) over a mean follow-up period of 43 months. In comparison with total shunts, diminished rates of postshunt encephalopathy (13% versus 40%) have been observed. Prograde portal blood flow has been preserved in 90% of 30 patients studied by perioperative portography. Shunt patency with continued prograde flow has been demonstrated at up to 9 years of follow-up. Investigators at three other centers have studied partial shunting using substantially similar techniques, with similar findings. Based on these results, we conclude that narrow-diameter shunts provide effective, long-lasting treatment for variceal hemorrhage due to portal hypertension in the alcoholic.
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McEllistrum MC, Collins JC, Powers JS. Admission serum albumin level as a predictor of outcome among geriatric patients. South Med J 1993; 86:1360-1. [PMID: 8093126 DOI: 10.1097/00007611-199312000-00007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This retrospective study consisted of 148 patients who were consecutively discharged during 1991 from a geriatric VA Hospital population. Seventy-six were 65 years of age or older, and all were male. Data included admission serum albumin level, age, length of stay, diagnosis, and disposition. Albumin level was negatively associated with length of stay and with outcome disposition. Albumin level was not associated with diagnosis. Age alone was not associated with albumin level, length of stay, diagnosis, or disposition. We conclude that a low albumin level is an independent predictor of a worse disposition. Age did not predict nutritional status, length of stay, diagnosis, or disposition.
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Powers JS, Zimmer J, Meurer K, Manske E, Collins JC, Greene HL. Direct assay of vitamins B1, B2, and B6 in hospitalized patients: relationship to level of intake. JPEN J Parenter Enteral Nutr 1993; 17:315-6. [PMID: 8271354 DOI: 10.1177/0148607193017004315] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
High-performance liquid chromatography assays for vitamins B1 by erythrocyte thiamine pyrophosphate, B2 by plasma and urinary riboflavin, and B6 by plasma pyridoxal phosphate and urinary pyridoxic acid were used to evaluate the B vitamin status of hospitalized patients. Over an intake range of up to 3.4 mg of thiamine per day and up to 4.1 mg of riboflavin per day, erythrocyte thiamine pyrophosphate and urine and plasma riboflavin increased proportionately with intake. There was no relationship between B6 intake and blood levels. Rather, a constant blood level was maintained with an intake range of 0.5 to 4 mg/d, and urinary pyridoxic acid showed a linear increase proportionate to intake. There were extremely variable blood and urine concentrations of B vitamins noted in our patient population.
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Collins JC, Muller RJ, Collins CL. Prenatal observation of umbilical cord abnormalities: a triple knot and torsion of the umbilical cord. Am J Obstet Gynecol 1993; 169:102-4. [PMID: 8333430 DOI: 10.1016/0002-9378(93)90139-a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Umbilical cord abnormalities can be observed with ultrasonography. Two cases are described where a triple knot and torsion of the umbilical cord are observed. These cases allow the elucidation of the mechanics of formation of a triknot and torsion abnormality.
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Das SK, Hinds JE, Hardy RE, Collins JC, Mukherjee S. Effects of physical stress on peroxide scavengers in normal and sickle cell trait erythrocytes. Free Radic Biol Med 1993; 14:139-47. [PMID: 8425720 DOI: 10.1016/0891-5849(93)90004-e] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Sickle cell trait subjects are potentially at risk with microvascular complications frequently associated with high altitude and extreme exertion. Studies conducted in our laboratory suggest that exposure of sickle cell trait subjects to treadmill exercise resulted in an increase not only in the susceptibility of red blood cells to oxidation but also in the density of RBC membrane. The trend of increased susceptibility of red cells to oxidation as a consequence of exercise was associated with relatively excessive production of H2O2, inefficient breakdown of H2O2 by GSH-Px- and catalase-catalyzed reactions, and inability/failure to show a transitory increase in the activity of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-generating enzymes.
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Collins JC, Levine G, Waxman K. Occult traumatic pneumothorax: immediate tube thoracostomy versus expectant management. Am Surg 1992; 58:743-6. [PMID: 1456598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Occult pneumothorax is pneumothorax identified by computed tomography but not seen on conventional chest radiographs. Twenty-seven occult traumatic pneumothoraces in 26 patients were identified retrospectively at the authors' level I trauma center. Of these, 24 patients survived to discharge or transfer; 2 died of brain injury. Eleven patients were treated immediately with tube thoracostomy (TT) and 13 were observed with interval chest radiography. The authors' data support the conclusion that it is safe to withhold immediate TT in patients who are hemodynamically stable. Close clinical observation and interval chest radiography can identify those patients who require subsequent TT. Prospective study of larger numbers of patients is needed to confirm the safety and cost efficacy of this approach.
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Collins JC, Buchanan DN, Thoene JG, Erickson RP, Brooks SS, Gluecksohn-Waelsch S. Metabolic studies in a mouse model of hepatorenal tyrosinemia: absence of perinatal abnormalities. Biochem Biophys Res Commun 1992; 187:340-6. [PMID: 1520318 DOI: 10.1016/s0006-291x(05)81498-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Radiation induced chromosomal deletions at the albino locus in the mouse, lethal when homozygous, cause abnormalities of expression of several unlinked liver specific genes. Recently, the gene encoding FAH was shown to be included in the deletions. Since in humans FAH mutations cause tyrosinemia type I, deletion homozygous mice were suspected of having tyrosinemia. Studies of plasma amino acids did not confirm this suspicion. Also, succinylacetone levels were normal in fetal and newborn livers of deletion homozygotes. The present evidence, therefore, does not support the assumption that the earlier described ultrastructural and enzyme abnormalities in deletion homozygotes are secondary effects of tyrosinemia caused by the deletion of FAH.
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Abstract
Modeling is a useful component of scientific investigation in nutrition. Nutrition scientists who would like to incorporate modeling into their studies frequently do not know where or how to begin. This paper describes a selected assortment of books, journals and articles, resource groups and individuals and computer software that may be of help to the beginning modeler and to those more experienced in modeling as well.
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Hardy RE, Mukherjee S, Hinds JE, Weaver C, Childs K, Patterson P, Talley PA, South MA, Collins JC, Das SK. Effects of physical stress on complete blood count and venous blood gas profile of individuals with sickle cell trait. Acta Haematol 1992; 88:114-9. [PMID: 1466192 DOI: 10.1159/000204664] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The association between sickle cell trait (SCT) and adverse effects of exercise has been controversial. While individuals with SCT are at higher risk of sudden death, the mechanism for this outcome remains to be elucidated. In order to shed light on this controversy, we have monitored venous blood count and blood gas parameter values in normal and SCT subjects during treadmill exercise. White and red blood cell counts and hemoglobin changed significantly over time in both the SCT and normal groups, with peak exercise values different from pre-exercise or post-exercise values. Red blood cell counts showed significant group-time interaction; increase in count during exercise was accentuated in SCT subjects. All blood gas parameters showed significant changes over time in both groups. O2 content was significantly higher in SCT than AA at all time intervals. O2 saturation, pO2 and CO binding to hemoglobin showed significant group-time interaction. Furthermore, O2 saturation for the combined groups was significantly greater at peak exercise and at rest than before exercise. It is possible that treadmill exercise causes microvascular shunting in SCT subjects, leading to a decrease in the peripheral utilization of oxygen.
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Collins JC, Ladinsky GA. High-energy photoproduction of jets. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1991; 43:2847-2855. [PMID: 10013682 DOI: 10.1103/physrevd.43.2847] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Zhang LQ, Collins JC, King PH. Indistinguishability and identifiability analysis of linear compartmental models. Math Biosci 1991; 103:77-95. [PMID: 1804443 DOI: 10.1016/0025-5564(91)90092-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two compartmental model structures are said to be indistinguishable if they have the same input-output properties. In cases in which available a priori information is not sufficient to specify a unique compartmental model structure, indistinguishable model structures may have to be generated and their attributes examined for relevance. An algorithm is developed that, for a given compartmental model, investigates the complete set of models with the same number of compartments and the same input-output structure as the original model, applies geometrical rules necessary for indistinguishable models, and test models meeting the geometrical criteria for equality of transfer functions. Identifiability is also checked in the algorithm. The software consists of three programs. Program 1 determines the number of locally identifiable parameters. Program 2 applies several geometrical rules that eliminate many (generally most) of the candidate models. Program 3 checks the equality between system transfer functions of the original model and models being tested. Ranks of Jacobian matrices and submatrices and other criteria are used to check patterns of moment invariants and local identifiability. Structural controllability and structural observability are checked throughout the programs. The approach was successfully used to corroborate results from examples investigated by others.
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Powers JS, Krantz SB, Collins JC, Meurer K, Failinger A, Buchholz T, Blank M, Spivak JL, Hochberg M, Baer A. Erythropoietin response to anemia as a function of age. J Am Geriatr Soc 1991; 39:30-2. [PMID: 1987254 DOI: 10.1111/j.1532-5415.1991.tb05902.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The erythropoietin (EPO) response to anemia was assessed for 244 subjects aged 1-64 years (mean 45.2 years) and 121 subjects aged 65-94 years (mean 68.3 years). Subjects included non-anemic individuals as well as those with anemia of various etiologies, excluding renal disease and pregnancy. Significant inverse correlations between serum immunoreactive EPO and hematocrit were noted for both groups. Regression lines failed to show a significantly lower slope or y-intercept for older compared to younger subjects. EPO levels were not significantly lower for older compared to younger subjects when controlled for hematocrit level. These results suggest that the EPO response to anemia in older subjects is similar to that of younger subjects.
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Collins JC, Permuth SF, Brooker RJ. Isolation and characterization of lactose permease mutants with an enhanced recognition of maltose and diminished recognition of cellobiose. J Biol Chem 1989; 264:14698-703. [PMID: 2670925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In the present study, lactose permease mutants were isolated which have an enhanced recognition toward maltose (an alpha-glucoside) and diminished recognition for cellobiose (a beta-glucoside). Nine mutants were isolated from a strain encoding a wild-type permease (pTE18) and nine from a strain encoding a mutant permease which recognizes maltose (pB15). All 18 mutants were subjected to DNA sequencing, and it was found that all mutations are single base substitutions within the lac Y gene effecting single amino acid substitutions within the protein. From the pTE18 parent, substitutions involved Tyr-236 to Phe or His; Ser-306 to Thr; and six independent mutants in which Ala-389 was changed to Pro. From pB15, Tyr-236 was changed to Phe or Asn, Ser-306 to Thr or Leu, Lys-319 to Asn, and His-322 to Tyr, Asn, or Gln. All 18 mutants exhibited enhanced recognition for maltose (compared with the pTE18 strain) and a diminished recognition for cellobiose. In addition, all mutants showed a diminished recognition toward beta-galactosides as well. The Phe-236, His-236, Leu-306, Asn-319, Tyr-322, Asn-322, and Gln-322 mutants were completely defective in the uphill accumulation of methyl-beta-D-thiogalactopyranoside whereas the Asn-236, Thr-306, and Pro-389 mutants could effectively accumulate methyl-beta-D-thiogalactopyranoside against a concentration gradient. The mutants obtained in this study, together with previous lactose permease mutants, tend to be found on transmembrane segments, and those which are on the same transmembrane segment are often found three or four amino acids away from each other. This pattern is consistent with a protein structure in which important amino acid side chains project from several transmembrane segments in such a way as to form a hydrophilic channel for the recognition and transport of H+ and galactosides. It is proposed that the mechanism for H+/lactose cotransport is consistent with a "flanking gate" model in which the protein contains a single recognition site for galactosides within the channel which is flanked on either side by gates.
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Abstract
Spinocerebellar degeneration in a 17-yr-old boy with abetalipoproteinemia was associated with vitamin E deficiency and hepatic steatosis. In liver biopsy samples before and after 15 mo of vitamin E treatment, hepatocellular peroxisomes were morphologically abnormal; pleomorphic, with a broadened range of sizes; often larger than normal; and with marginal bars in some. In the first sample, peroxisomes exhibited matrical heterogeneity and dense nucleoids. Peroxisomes in the second biopsy sample lacked nucleoids and contained more homogeneous matrices. The mean peroxisomal diameter increased from 0.77 +/- 0.33 to 0.86 +/- 0.32 microM (normal, 0.62 +/- 0.14). These observations raise the possibility that peroxisomes may be involved in the metabolism of apolipoprotein B or may be affected by the disturbances of hepatocellular lipid metabolism caused by this disease.
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Collins JC, Permuth SF, Brooker RJ. Isolation and Characterization of Lactose Permease Mutants with an Enhanced Recognition of Maltose and Diminished Recognition of Cellobiose. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)63754-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Allan LG, Siegel S, Collins JC, MacQueen GM. Color aftereffect contingent on text. PERCEPTION & PSYCHOPHYSICS 1989; 46:105-13. [PMID: 2762097 DOI: 10.3758/bf03204969] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
During adaptation, two different letter strings (each five or six letters) were presented to subjects alternately, one in green and the other in magenta. The extent to which these letter strings subsequently elicited a color aftereffect was assessed. In different experiments, the chromatic letter strings consisted of words and nonwords. The results indicated that letter strings that form English words can contingently elicit a color aftereffect. This was the case even when the words were anagrams. There was no evidence that nonword letter strings could contingently elicit such an aftereffect, even when the nonwords conformed to English orthography. The results are relevant to understanding other contingent color aftereffects (McCollough effects), illusory color noted by computer operators who work at monochrome (green or amber) displays, and the processing of text.
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May ME, Collins JC. Rapid assessment of average ratios: application to turnover studies. THE AMERICAN JOURNAL OF PHYSIOLOGY 1989; 257:E124-5. [PMID: 2750895 DOI: 10.1152/ajpendo.1989.257.1.e124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The calculation of a set of ratios from two sets of paired experimental data is a common practice. The ratio of the averages of two sets is in general not equal to the average of the ratios of individual pairs, and there is no predictable relation if both sets of data are unspecified real numbers. However, we prove here that the ratio of averages is the minimum bound for the average of ratios if the numerators of each ratio are identical. This is the practice for many steady-state turnover experiments, and thus summary data can be reliably utilized in this case.
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Powers JS, Lichtenstein MJ, Collins JC, Krantz SB, Greene HL, Buchholz T. Serum erythropoietin in healthy older persons. J Am Geriatr Soc 1989; 37:388-9. [PMID: 2921461 DOI: 10.1111/j.1532-5415.1989.tb05513.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Powers JS, Folk MC, Collins JC, Burger MC, Wilson P, Stocking B. Re: The influence of vitamin supplements of micronutrient levels in healthy elderly subjects. J Am Coll Nutr 1989; 8:171-2. [PMID: 2708732 DOI: 10.1080/07315724.1989.10720292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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