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Chandraratna PA, Nimalasuriya A, Kawanishi D, Duncan P, Rosin B, Rahimtoola SH. Identification of the increased frequency of cardiovascular abnormalities associated with mitral valve prolapse by two-dimensional echocardiography. Am J Cardiol 1984; 54:1283-5. [PMID: 6507298 DOI: 10.1016/s0002-9149(84)80081-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Two-dimensional echocardiography (2-D echo) was performed in 86 consecutive patients with mitral valve prolapse (MVP) and in 25 normal subjects. In normal subjects, mitral leaflet thickness was 3.5 +/- 0.8 mm (mean +/- standard deviation) and the mitral leaflet thickness to aortic wall thickness ratio was 1.0 +/- 0.2. Patients with MVP were separated into 2 groups: those with normal mitral thickness (less than or equal to mean + 2 SD observed in normal subjects, i.e., less than or equal to 5.1 mm) and normal mitral thickness to aortic wall thickness ratio (less than or equal to mean + 2 SD observed in normal subjects, i.e., less than or equal to 1.4) (group I) and others in whom these values were increased (group II). In group I, mitral thickness was 3.6 +/- 0.6 mm and mitral thickness to aortic wall thickness ratio was 1.1 +/- 0.1, and in group II, mitral thickness was 8.8 +/- 1.2 mm and mitral thickness to aortic wall thickness ratio was 2.2 +/- 0.5. The only significant cardiovascular abnormalities in group I were mitral regurgitation in 2 patients and tricuspid valve prolapse in 1 patient. In group II, 7 patients had clinically significant mitral regurgitation, 8 had aortic root abnormalities, 4 had tricuspid valve prolapse and 6 had Marfan's syndrome. Cardiovascular abnormalities were present in 60% (18 of 30) of patients in group II and in 6% (3 of 56) of patients in group I (p less than 0.001). Two-dimensional echo enabled the identification of a subset of patients with MVP who had thickened mitral leaflets. These patients had an increased incidence of cardiovascular abnormalities.
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Duncan P, Feh C, Gleize J, Malkas P, Scott A. Reduction of inbreeding in a natural herd of horses. Anim Behav 1984. [DOI: 10.1016/s0003-3472(84)80290-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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53
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Tietz NW, Rinker AD, Burtis C, Duncan P, Ervin K, Ewen L, Hørder M, Mathieu M, Petitclerc C, Grisley D. Transferability studies for the AACC reference method and the IFCC method for measurement of alkaline phosphatase activity. Clin Chem 1984. [DOI: 10.1093/clinchem/30.5.704] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
We present the results of measurements of alkaline phosphatase activity from interlaboratory transferability studies conducted by 12 laboratories in five countries. The variability, as demonstrated by within-day precision (CV less than or equal to 2.6%), between-day precision (CV less than or equal to 3.6%), and between-lab precision (CV less than or equal to 6.3%) establishes the transferability of this method for alkaline phosphatase. Some common errors encountered in enzyme measurements that affect the accuracy and precision of the measurements are listed.
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54
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Tietz NW, Rinker AD, Burtis C, Duncan P, Ervin K, Ewen L, Hørder M, Mathieu M, Petitclerc C, Grisley D. Transferability studies for the AACC reference method and the IFCC method for measurement of alkaline phosphatase activity. Clin Chem 1984; 30:704-6. [PMID: 6713630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We present the results of measurements of alkaline phosphatase activity from interlaboratory transferability studies conducted by 12 laboratories in five countries. The variability, as demonstrated by within-day precision (CV less than or equal to 2.6%), between-day precision (CV less than or equal to 3.6%), and between-lab precision (CV less than or equal to 6.3%) establishes the transferability of this method for alkaline phosphatase. Some common errors encountered in enzyme measurements that affect the accuracy and precision of the measurements are listed.
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Abstract
During a 3-year period, seven children with bacterial tracheitis were admitted to the intensive care unit of the Winnipeg Children's Hospital. The illness was characterized by fever, toxicity, and stridor. Respiratory difficulty was secondary to copious thick purulent tracheal secretions. In the majority of patients the illness was caused by Staphylococcus aureus, and the rest had Hemophilus influenzae infection. Viral studies in five patients were negative. Most patients required endotracheal intubation and frequent tracheal toilet to prevent serious airway obstruction. In our ICU, bacterial tracheitis accounted for about 14 per cent of admissions with infectious upper airway obstructive illness, while epiglottis and croup accounted for 55 per cent and 31 per cent, respectively. Only 5 per cent of children with croup admitted to the hospital were admitted to the ICU. Bacterial tracheitis has reappeared, at least in North America, as an important and serious cause of obstructive upper airway disease in children and must be recognized early in order to prevent catastrophic airway obstruction.
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Tietz NW, Burtis CA, Duncan P, Ervin K, Petitclerc CJ, Rinker AD, Shuey D, Zygowicz ER. A reference method for measurement of alkaline phosphatase activity in human serum. Clin Chem 1983. [DOI: 10.1093/clinchem/29.5.751] [Citation(s) in RCA: 182] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
We present an official AACC reference method for the measurement of alkaline phosphatase, the culmination of optimization experiments conducted by a group of independent laboratories. The details of this method and evaluation of factors affecting the measurement are described. A metal ion buffer has been incorporated that maintains optimal and constant concentrations of zinc(II) and magnesium(II) ions. Final reaction conditions are: pH (30 degrees C), 10.40 +/- 0.05; 2-amino-2-methyl-1-propanol buffer, 0.35 mol/L; 4-nitrophenyl phosphate, 16.0 mmol/L; magnesium acetate, 2.0 mmol/L; zinc sulfate, 1.0 mmol/L; and N-(2-hydroxyethyl)ethylenediaminetriacetic acid, 2.0 mmol/L.
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Tietz NW, Burtis CA, Duncan P, Ervin K, Petitclerc CJ, Rinker AD, Shuey D, Zygowicz ER. A reference method for measurement of alkaline phosphatase activity in human serum. Clin Chem 1983; 29:751-61. [PMID: 6404566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We present an official AACC reference method for the measurement of alkaline phosphatase, the culmination of optimization experiments conducted by a group of independent laboratories. The details of this method and evaluation of factors affecting the measurement are described. A metal ion buffer has been incorporated that maintains optimal and constant concentrations of zinc(II) and magnesium(II) ions. Final reaction conditions are: pH (30 degrees C), 10.40 +/- 0.05; 2-amino-2-methyl-1-propanol buffer, 0.35 mol/L; 4-nitrophenyl phosphate, 16.0 mmol/L; magnesium acetate, 2.0 mmol/L; zinc sulfate, 1.0 mmol/L; and N-(2-hydroxyethyl)ethylenediaminetriacetic acid, 2.0 mmol/L.
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Williams SD, Duncan P, Einhorn LH. Phase II study of AMSA in refractory testicular cancer. CANCER TREATMENT REPORTS 1983; 67:309-310. [PMID: 6687560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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59
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60
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Friesen RM, Duncan P, Tweed WA, Bristow G. Appraisal of pediatric cardiopulmonary resuscitation. CANADIAN MEDICAL ASSOCIATION JOURNAL 1982; 126:1055-8. [PMID: 7042063 PMCID: PMC1863287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Sixty-six patients more than 30 days and less thant 16 years of age suffering an unexpected cardiac arrest in an 18-month period were included in a study of resuscitative measures in children. Six children survived to be discharged from hospital. Respiratory disease accounted for most (29%) of the cardiac arrests, but it also had the most favourable prognosis, 21% of the 19 patients surviving. None of the patients survived whose cardiac arrest was secondary to sepsis or trauma, even when the resuscitative efforts were initially successful. Only 1 of the 41 patients who had a cardiac arrest outside of hospital survived, and only 1 of the 34 patients who presented with asystole survived, and then with considerable damage to the central nervous system. The interval between cardiac arrest and application of basic life support was substantially shorter among the survivors. Also, most of the survivors did not present with asystole. The results of this study suggest that survival among resuscitated children is no better than that among adults but can be improved with early recognition and monitoring of children at risk. earlier application of basic and advanced life support, improved education of medical and lay personnel, and further research into pediatric resuscitative techniques.
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Duncan P, Gochman N, Bayse D, Burnett R, Carey N, Carter R, Fellows WD, Garber C, Kessler G, McComb R, Miller W, Nast P, Ryan W, Schaffer R, Tejeda B, Vanderlinde R, Widdowson G. A candidate reference method for uric acid in serum. II. Interlaboratory testing. Clin Chem 1982. [DOI: 10.1093/clinchem/28.2.291] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
We describe the interlaboratory testing of a candidate Reference Method (Part I) for uric acid in serum. The method is based on the ultrasound spectrophotometric quantitation of uric acid before and after incubation with uricase. A comprehensive investigation involving 12 laboratories was organized to document the transferability, intra- and interlaboratory precision, and general reliability of the candidate Reference Method. The interlaboratory CV with this method was about 2 to 6% for uric acid concentrations ranging from 0.12 to 0.60 mmol/L. The results detailed here demonstrate that the method can be successfully duplicated among different laboratories.
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Duncan P, Gochman N, Bayse D, Burnett R, Carey N, Carter R, Fellows WD, Garber C, Kessler G, McComb R, Miller W, Nast P, Ryan W, Schaffer R, Tejeda B, Vanderlinde R, Widdowson G. A candidate reference method for uric acid in serum. II. Interlaboratory testing. Clin Chem 1982; 28:291-3. [PMID: 7055950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We describe the interlaboratory testing of a candidate Reference Method (Part I) for uric acid in serum. The method is based on the ultrasound spectrophotometric quantitation of uric acid before and after incubation with uricase. A comprehensive investigation involving 12 laboratories was organized to document the transferability, intra- and interlaboratory precision, and general reliability of the candidate Reference Method. The interlaboratory CV with this method was about 2 to 6% for uric acid concentrations ranging from 0.12 to 0.60 mmol/L. The results detailed here demonstrate that the method can be successfully duplicated among different laboratories.
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63
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Buskist WF, Miller HL, Duncan P, Fleming DE. Associative history determines strength of taste-aversion conditioning in thiamine-deficient rats. Physiol Behav 1980; 25:989-92. [PMID: 6261274 DOI: 10.1016/0031-9384(80)90323-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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64
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Abstract
Laterality of hand, foot, eye, and ear was measured in a sample of 1964 subjects, ranging in age from 8 to 100 years. Age trends were found, with hand, foot, and eye preference becoming more right-sided and ear preference becoming more left-sided with increasing age. Sex differences emerged in foot, eye, and ear preference but these did not systematically interact with the age variable. Several causal mechanisms are proposed but none can fully explain either the direction or the magnitude of the observed age changes. Thus, these data are most consistent with the view that the study of sidedness in humans should proceed with a consideration of a complex of underlying factors and individual difference variables.
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Brock DJ, Barron L, Duncan P, Scrimgeour JB, Watt M. Significance of elevated mid-trimester maternal plasma-alpha-fetoprotein values. Lancet 1979; 1:1281-2. [PMID: 87736 DOI: 10.1016/s0140-6736(79)92238-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In a prospective trial of 15,481 pregnancies, 667 women (4.3%) had two sequential mid-trimester plasma-alpha-fetoprotein (A.F.P.) values above 2 times the median. The outcome of these pregnancies was open neural-tube defect (12.4%), birthweight less than 2.5 kg (10.3%), twins (9.8%), fetal wastage (9.5%), perinatal death (2.6%), other (1.3%), and "normal" singleton (54.1%). At higher A.F.P. cutoffs the proportion of "normal" singleton pregnancies declined rapidly, being 19% at 3 times the median and 9% at 4 times the median. If it is assumed that ultrasonography and amniotic-fluid A.F.P. assay can detect twins and most cases of neural-tube defect, the outcome of the residual pregnancies is still strongly influenced by plasma-A.F.P. level. Thus at a cut-off of 4 times the median two-thirds of the pregnancies in this residual group will end in spontaneous abortion, stillbirth, or neonatal death. It is suggested that counselling of women taking part in A.F.P. screening programmes should be strongly influenced by maternal plasma-A.F.P. levels, even if ultrasonographic findings and amniotic-fluid levels are normal.
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Hobson PA, Duncan P. Sign learning and profoundly retarded people. MENTAL RETARDATION 1979; 17:33-7. [PMID: 481211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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67
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Robinson N, Duncan P, Gehrt M, Sances AS, Evans S. [Electrode implantation and stimulation in the hippocampus]. ARCHIVES OF NEUROLOGY 1976; 33:847. [PMID: 999547 DOI: 10.1001/archneur.1976.00500120051009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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68
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Robinson N, Duncan P, Gehrt M, Sancres A, Evans S. Histochemistry of trauma after electrode implantation and stimulation in the hippocampus. ARCHIVES OF NEUROLOGY 1975; 32:98-102. [PMID: 164845 DOI: 10.1001/archneur.1975.00490440048007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Electrodes were implanted into the rat hippocampus in both hemispheres for increasing periods of up to 60 days, and the effects of trauma and electrical stimulation of enzymes controlling cell metabolism in the region of implantation were examined and assessed in relation to studies on humans. In the unstimulated hippocampus as a control, enzyme changes were mainly confined to a narrow area of tissue damage surrounding the electrode. The enzyme changes in response to trauma varied widely; some enzymes controlling tissue respiration showed early and rapid changes, increasing in hyperactive, swollen glial cells and vascular endothelium and decreasing in nerve cells and neuropile. Acid phosphatase activity also increased rapidly in glial cells; other phosphate-releasing enzymes increased more gradually with time. A turning point in these chages was apparent between 25 and 40 days, followed by a reversion to more normal levels at 60 days. Electrical stimulation of the hippocampus in the contralateral hemisphere produced no detectable enzyme changes from those of the unstimulated hippocampus.
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69
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Gladwell P, Duncan P, Barham K, Kenny J. Amnioscopy of late pregnancy with fetal membrane and decidual cytology. Acta Cytol 1974; 18:333-7. [PMID: 4526250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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70
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Duncan P. Parental attitudes and interactions in delinquency. Child Dev 1971; 42:1751-65. [PMID: 5146018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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