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At least 37 records · Page 2Linked to original sources

PubMed1992

[Validity of the proximal isovelocity surface area color Doppler method for calculating the valve area in patients with mitral stenosis; comparison with the two-dimensional echocardiographic method].

BACKGROUND: The proximal isovelocity surface area (PISA) method, assessed by color Doppler echocardiography, has gained acceptance as a means of calculating flow rate through regurgitant orifice. The method can also be used to derive mitral valve area (MVA), by continuity equation, in patients with mitral stenosis (MS). The aim of this study was to compare the PISA method with the two-dimensional echocardiographic planimetry (2D) method and pressure half-time method (PHT) in MVA calculations in a group of 37 patients with MS. METHODS AND RESULTS: All of these patients had satisfactory MVA by 2D method. There were 22 female and 15 male; age 56 +/- 11 years (range 32-71); 19 were in sinus rhythm (SR) and 18 in atrial fibrillation (AF); 17 patients had pure MS, while the remaining 20 had associated mitral regurgitation (MR); in 23 patients the orifice morphology was circular or elliptic, and was defined as regular; while in 14 patients the morphology was irregular for the presence of two or more nodular calcifications on the commissures or leaflet's edges. MVA by PISA method was calculated assuming a uniform radial flow convergence region along a hemispherical surface, according to the formula: MVA = 2 pi r2 Vn(1-cos theta)/Vmax; where r was the PISA radius measured in 2D from the first alias to the mitral leaflet's edge; Vn was the flow velocity at radial distance from the mitral orifice; Vmax was the peak transmitral velocity by CW Doppler; 1-cos theta was a factor that accounted for the inflow angle formed by the mitral leaflets. The Nyquist limit was lowered to 29 cm/sec. Alpha angle formed by the mitral leaflets ranged between 86 degrees and 134 degrees; average 110 degrees +/- 10 degrees. 2D MVA was 1.33 +/- 0.37 cm2; range 0.69-2.2 cm2; PHT MVA was 1.29 +/- 0.34 cm2; range 0.70-2.1 cm2; PISA MVA was 1.18 +/- 0.36 cm2; range 0.47-1.95 cm2. The PISA method underestimates MVA by 0.15 +/- 0.21 cm2, in comparison with the 2D method; and by 0.11 +/- 0.18 cm2 in comparison with PHT method (p ns). The correlation between 2D and PISA MVA was: r = 0.84; p < 0.001; y = 0.83x + 0.06; 95% confidence intervals +/- 0.40 cm2; and between PHT and PISA MVA was: r = 0.79; y = 0.84x + 0.09; p < 0.001; 95% confidence intervals +/- 0.46 cm2. The correlation coefficient was similarly good in patients with SR or AF, and did not significantly change in patients with pure MS or MS+MR; neither did it vary with respect to the orifice morphology (p < 0.001 for all the variables considered), except for the correlation PHT-PISA in the group of patients with irregular orifice morphology (r = 0.70; p = 0.005). The interobserver and intraobserver variability were, respectively: 2.2% and 4.4% for 2D MVA; 3.4% and 3.8% for PHT MVA; 5.2% and 3.5% for the PISA radius; 6.1% and 4.4% for the alpha angle; 10.2% and 7.2% for PISA MVA (F ratio of variances ns). CONCLUSIONS: In conclusion, the PISA method allows accurate assessment of MVA in patients with MS, regardless of cardiac rhythm or additional MR. Moreover, our study suggests that orifice morphology does not affect the accuracy of this method.

Adult↗

PubMed1992

A new method for measurement of femoral anteversion. A comparative study with other radiographic methods.

A new biplanar method of measuring femoral anteversion, which may be considered a modified Magilligan's method, is described. In addition to the true antero-posterior radiograph, a true translateral radiograph is taken, instead of a transcervical lateral radiograph as in the Magilligan method. The acute angles (alpha and gamma) between the long axes of the shaft and neck of the femur on both the antero-lateral and lateral radiographs are measured. The angle (gamma') of anteversion is obtained by the trigonometric formula; tan gamma' = tan/tan alpha. The femoral anteversion in 20 adult dried femora and 40 femora in 20 children was measured by the Magilligan method, the authors' method and the conventional CT method. Compared with direct measurement in the dried femora, it was found that both the Magilligan and the authors' methods tended to overestimate and the CT method tended to underestimate (p < 0.05) the anteversion. In children's femora, a similar trend was observed among the three methods and the measurements by each method differed significantly from the other (p < 0.05). We feed that our method of biplanar measurement of femoral anteversion is more accurate, although probably marginally, than the conventional Magilligan method. It also has some relative advantages in clinical application in that positioning is easier, rotation is better controlled, and less time is consumed.

Adolescent↗

PubMed1991

[Clinical study of new technique for collection of EPS, prostate catheter method--comparison with Meares and Stamey's method].

We newly developed a catheter for expressed prostatic secretions (EPS) collection and examined whether or not EPS can be collected with this catheter without contamination of urethral bacteria. The clinical value of the prostate catheter method was examined in comparison with Meares & Stamey's method. Both prostate catheter and Meares & Stamey's method were performed by crossover method in 11 patients who were highly suspected of chronic prostatitis based on symptoms and physical findings. Three of the 4 cases of bacterial prostatitis on Meares & Stamey's method were diagnosed as bacterial prostatitis by the prostate catheter method, but the remaining one was diagnosed as prostatodynia. One of the 3 cases of non-bacterial prostatitis on Meares & Stamey's method was diagnosed as non-bacterial prostatitis, but the other two cases were diagnosed as urethritis. Four cases of prostatodinia on Meares & Stamey's method were given the same diagnosis by the prostate catheter method. In conclusion, eight of 11 cases received the same diagnosis by the two different method. The remaining three cases were given different diagnosis, but the prostate catheter method gave a more accurate diagnosis. We concluded that the prostate catheter method is useful in the differential diagnosis of bacterial prostatitis and non-bacterial prostatitis.

Adult↗

PubMedDate not supplied

Comparison of a commercial method for total protein with a candidate reference method.

The biuret method for total protein has been compared on the Boehringer Mannheim Diagnostics (BMD) Hitachi 717 Analyzer with a candidate reference method in efforts to standardize the BMD method. The methods were compared using 115 paired serum specimens collected during morning rounds at the Roger Williams Hospital. Results from the test method were compared to the reference method using a statistical procedure for quantifying bias between analytical methods. Linear regression statistics were also calculated. The Hitachi 717 biuret method shows no bias when compared to the reference method (z = -0.90), and there is acceptable correlation between the two methods (y = 0.86, m = 0.86, r = 0.896). The Hitachi method is linear to 15.0 g per dL and demonstrates excellent precision (CV less than or equal to 2.14 percent, N = 140). The Hitachi 717 biuret method has been found to be excellent in all respects and its use is recommended as a convenient and accurate means of measuring total protein.

Blood Chemical Analysis↗

PubMed1978

A new method for investigating the relation between change and initial value in longitudinal blood pressure data. II. Comparison with other methods.

Whether initial value affects blood pressure change or not is of interest in longitudinal blood pressure studies. The change/initial value relationship is, however, biased by the regression towards the mean phenomenon, as blood pressure measurements contain random errors (short-term intra-individual variation and measurement errors). Two methods (here called C and D) of avoiding this bias have earlier been proposed and used in population studies in South Wales and Framingham, with conflicting results. In the preceding paper a new method of avoiding the bias has been presented. In the present paper a comparison of the new method with the two earlier is made by applying them to the same data set. Method C indicates, as in South Wales, a highly significant positive relationship, while method D (as in Framingham) and the new method give a regression coefficient close to zero. The structure of the three methods is analysed. Method C is shown to be valid only under very restricted conditions and is best avoided. Method D gives a fairly accurate result, but underestimates the coefficient by approximately 30% in this case. The new method proposed seems to be the best method hitherto for this kind of analysis.

Blood Pressure Determination↗

PubMed1976

[Consideration on the King-Armstrong method and on the kinetic method for the measurement of the alkaline phosphatase activity in serum (author's transl)].

The comparative study of a determined time method, according to King-Armstrong, for the measurement of the alkaline phosphatase activity in serum and of a kinetic method consents us to make the following points: 1) the reagents used in the King-Armstrong method are easily prepared and are stable for months, with the sole addition of cloroform to the substrate and to the buffer to avoid the growth of moulds. 2) The substrate used for the kinetic method undergoes spontaneous Xydrolysis in acqueous solution, which makes it possible to keep it refrigerated for a limited number of days. Freezing at - 20 degrees C does not improve the situation. 3) The degree of precision within the series and between the series is the same for the two methods, and very good. 4) From the working point of view the method of "determined time" is advantageous for few samples, while the kinetic method becomes preferable when the number of samples goes over 20 and 30 a day, provided that it is linked with the suitable automatic apparatus. 5) The results of the measurement of the enzyme activity found with the two methods on 120 sera of normal and pathological subjects have shown good correlation, confirming the clinical diagnostic value of the results obtained by the kinetic method, which uses a transphosphorilant buffer and their congruency with those obtained by the classical King-Armstrong method.

Alkaline Phosphatase↗

PubMed1979

The effectiveness of the psychodramatic double method, the reflection method, and lecturing in the training of empathy.

Studied the effectiveness of the psychodramatic Double method, the Reflection method, and the Lecture method in improving empathic ability. Sixty-four high school sophomores were assigned randomly to four groups of 16 Ss, 8 males and 8 females, each. Three groups received one of the three training methods and the fourth served as no-training control. The Ss' level of empathy, before and after the training, was measured by a modified version of the Accurate Empathic Scale. The results showed that all three training methods produced significant improvements compared with the control group. The effect of the Double method was significantly greater than that of the other two methods. The Reflection method ranked second, yet was not significantly better than the Lecture method. Females scored higher than males both before and after the training, but there was no significant sex and training method interaction effect.

Adolescent↗

PubMed1977

Evaluation of automated glucose oxidase methods for serum glucose: comparison to hexokinase of a colorimetric and an electrometric method.

Two automated glucose oxidase methods have been evaluated with respect to accuracy, precision, recovery, linearity and various potential interferences. Trinder's method on an AutoAnalyzer II had a between-day coefficient of variation (C.V.) of 2.6% (mean 228 mg/dl), was linear to 500 mg/dl, and produced a mean recovery of 99.7%. Comparison of Trinder's method with a manual, blanked hexokinase method yielded the regression equation: TR=--1.95 + HEX (1.04); Spearman's rho correlation coefficient was: 0.974. The Beckman System I glucose method had a between-day C.V. of 1.6% (mean 198 mg/dl), was linear to 500 mg/dl, and recovered an average of 98.0% of added glucose. Comparison with the same hexokinase method yielded: SYI = 1.27 + HEX (1.02: Spearman's rho = 0.991. None of the possible interfering compounds tested caused significant deviation of results by either method within the range of concentrations encountered physiologically. Trinder's method on the AutoAnalyzer II and the System I method are accurate, precise methods and are highly recommended for routine use in the clinical laboratory.

Autoanalysis↗

PubMed1989

Prediction of imipramine serum levels in enuretic children by a Bayesian method: comparison with two other conventional dosing methods.

The aim of the present study was to characterize the kinetic behavior of imipramine (IMI) and desipramine in enuretic children and to evaluate the performance of different methods for dosage prediction based on individual and/or population data. The study was carried out in 135 enuretic children (93 boys) ranging in age between 5 and 13 years undergoing treatment with IMI in variable single doses (25-75 mg/day) administered at night. Sampling time was one-half the dosage interval at steady state. The number of data available for each patient varied (1-4) and was essentially limited by clinical criteria. Pharmacokinetic calculations were performed using a simple proportional relationship (method 1) and a multiple nonlinear regression program (MULTI 2 BAYES) with two different options: using the ordinary least-squares method (method 2) and the least-squares method based on the Bayesian algorithm (method 3). The results obtained point to a coefficient of variation for the level/dose ratio of the drug (58%) that is significantly lower than that of the metabolite (101.4%). The forecasting capacity of method 1 is deficient both regarding accuracy [mean prediction error (MPE) = -5.48 +/- 69.15] and precision (root mean squared error = 46.42 +/- 51.39). The standard deviation of the MPE (69) makes the method unacceptable from the clinical point of view. The more information that is available concerning the serum levels, the greater are the accuracy and precision of methods (2 and 3). With the Bayesian method, less information on drug serum levels is needed to achieve clinically acceptable predictions.

Adolescent↗

PubMed1990

Evaluation of test sensitivity and test specificity of three field methods for quantification of chloroquine in urine using liquid chromatography as reference method.

We have evaluated three quantitative colorimetric methods [bromthymol blue (BTB), Haskins, and Saker-Salomons (S-S)] for measurement of concentrations of chloroquine (CQ) in urine. A graphical evaluation of test sensitivity and test specificity at different concentrations of CQ in authentic urine samples was used. Liquid chromatography (LC) was used as a reference method. The Haskins method showed the highest test specificity (89%) and test sensitivity (97%), at a discrimination value of 2 mumols/L. At the same sensitivity (97%) as the Haskins method, S-S and BTB methods had test specificities of 49 and 13%, respectively. The correlation coefficients between the LC method and the colorimetric methods were all higher than 0.94 at a urinary concentration range of 2-100 mumols/L. The intra- and interassay variations for the colorimetric methods were all uniformly less than 15% at 2 mumols/L, but the Haskins method showed less variation than the other two methods.

Child↗

PubMed1990

Blinded comparison of a direct immunofluorescent monoclonal antibody staining method and a Giemsa staining method for identification of Pneumocystis carinii in induced sputum and bronchoalveolar lavage specimens of patients infected with human immunodeficiency virus.

A new direct immunofluorescence monoclonal antibody (DFA) method (Genetic Systems, Inc., Seattle, Wash.) for identification of Pneumocystis carinii in induced sputum and bronchoalveolar lavage specimens was compared in a blinded study with an established Giemsa stain method. We evaluated 148 consecutive clinical specimens from 104 patients with the following results. For the 67 patients (64%) infected with the human immunodeficiency virus (HIV), 49 were initially negative by both the DFA and the Giemsa methods, none were negative by DFA and positive by Giemsa, 6 were positive by DFA and negative by Giemsa, and 12 were positive by both methods, for a sensitivity and a negative predictive value of greater than 99%. For the six patients positive by DFA and negative by Giemsa, all were positive by both methods on evaluation of subsequently obtained clinical specimens, suggesting a specificity of greater than 99% and a false-positive rate of less than 1%. For 37 patients whose HIV status was negative or unknown, 35 were negative by both methods and 2 were positive by DFA and negative by Giemsa. The DFA method was simple to perform and required less time for scoring of stained slides than the Giemsa method, but care had to be taken to avoid false-positive readings due to extraneous fluorescence. This study indicates that the DFA method represents an advance as a sensitive, simple, and rapid way to identify P. carinii in induced sputum and bronchoalveolar lavage specimens from HIV-infected patients and suggests greater sensitivity of the DFA than the Giemsa method in this patient population.

Antibodies, Monoclonal↗

PubMed1981

New simple early diagnostic methods using Omura's "Bi-Digital O-Ring Dysfunction Localization Method" and acupuncture organ representation points, and their applications to the "drug & food compatibility test" for individual organs and to auricular diagnosis of internal organs--part I.

By critically evaluating exceptions which may lead to false diagnoses, as well as by improving the currently-used applied kinesiology diagnostic method (="Dysfunction Localization Method"), the author was able to develop the "Thumb-Index Finger Bi-Digital O-Ring Diagnostic Method," using the Applied Kinesiology Dysfunction Localization Principle. By combining the author's "Bi-Digital O-Ring Dysfunction Localization Method" with clinically useful organ representation points in acupuncture medicine (where the presence of tenderness at the organ representation point is used for diagnosis as well as for the location of treatment), it has become possible to make early diagnoses of most of the internal organs, with an average diagnostic accuracy of over 85%, without knowing the patient's history or using any instruments. The method can detect dysfunctioning or diseased organs even before tenderness appears at the organ representation point, with an applied force of less than 1 gm/mm2 on the skin surface, while the detection of tenderness at the organ representation point often requires a minimum applied force of 80-100 gm/mm2. The method was applied to the "Drug and Food Compatibility Test" to determine the probable effects of a given food or drug on individual internal organs without going through time-consuming, expensive laboratory tests. It was also applied to auricular organ representation points and their evaluation, and has succeeded in increasing their diagnostic sensitivity. The method was also used for the evaluation of magnetic fields. Usually the North pole increased muscle strength and the South pole weakened it at most parts of the body. This simple, improved, economical diagnostic method may have invaluable implications in clinical diagnosis, treatment and drug research. Key Words: early diagnostic methods, "Thumb-Index Finger Bi-Digital O-Ring Diagnostic Method," applied kinesiology, cardio-vascular diseases, drugs, tenderness, pain, pain medicine, anti-hypertensive drugs, cardio-vascular drugs, aspirin, Bufferin, gastro-intestinal system, muscle strength, nutrition, magnetic field, sensory nerve, spinal cord, brain stem. Inderal.

Acupuncture Therapy↗

PubMed1988

[Clinical evaluation of vesicoureteroneostomy. II. Efficacy of surgery by Boari's method in eight and the psoas-hitch method in eight cases].

Vesicoureteroneostomy was performed by Boari's method on 8 patients and the psoas-hitch method on 8 patients during the 16 years from 1969 to 1986. Although Boari's method without the formation of a submucosal tunnel was employed for the initial 4 patients, the formation of this type of tunnel was a general principle for all patients thereafter. In choosing the surgical method, the psoas-hitch method was assigned to patients in whom it was possible to extend the urinary bladder to the upper part of the common iliac vessel and in whom the ureter allowed the formation of a submucosal tunnel, and Boari's method was assigned to those in whom it is was not possible to reach the ureter or to form a submucosal tunnel or in whom the ureter would be tensed. The mean length of the resected section of ureter was 75 mm for Boari's method and 43.2 mm for the psoas-hitch method. Follow-up observations revealed the presence of VUR in 2 patients who underwent surgery by the initial form of Boari's method and in 1 patient who underwent surgery by the psoas-hitch method. There was no ureteral stenosis or renal hypofunction in any of the patients.

Adult↗

PubMed1988

Bias between enzymatic methods and the reference method for cholesterol.

Assaying 312 serum samples, we compared four enzymatic methods for serum cholesterol with the Reference Method (modified Abell-Kendall) of the Centers for Disease Control (CDC). The means for the aca, TDx, and SMAC methods (2.27, 2.27, and 2.24 g/L, respectively) were significantly higher (P less than 0.05) than those of the Reference Method and the RA-1000 method (2.19 and 2.18 g/L, respectively). The biased methods had positive proportional and (or) systematic biases. Results with these methods were 2.6% to 4.9% higher than with the Reference Method. The assigned concentrations of cholesterol in the calibration materials for the SMAC and aca agreed with those obtained by the Reference Method, but were lower for the TDx and higher for the RA-1000. These findings document positive biases for cholesterol with three enzymatic methods and suggest that misassignment of calibrators is not primarily responsible for the biases found with the aca and SMAC. It may, however, to be a significant factor for the TDx.

Autoanalysis↗

PubMedDate not supplied

Performance characteristics of methods of analysis used for regulatory purposes. I. Drug dosage forms. F. Gravimetric and titrimetric methods.

The original gravimetric and titrimetric methods approved by AOAC for the analysis of pharmaceutical preparations, particularly during the period 1915-1950, show precision, recovery, and outlier parameters approximately the same as those exhibited by the previously reviewed instrumental methods that are currently used. Fifty-nine published collaborative studies utilized gravimetric methods and 85 used titrimetric. The studies of the gravimetric methods encompassed 47 analytes, 95 dosage forms, and 136 assays; the corresponding figures for the titrimetric studies are 72, 112, and 152. An average of approximately 7 laboratories participated per study. The line of best fit of the relative standard deviation between-laboratories (RSDR) plotted against the negative logarithm of the fractional concentration, C, extends from 1.2 and 1.0% for the gravimetric and titrimetric methods, respectively, at 100% concentration to 2.2 and 2.8% at 1.0% concentration. Below this concentration the precision of the titrimetric methods degenerates faster than that of the gravimetric methods. Above about 0.1% concentration the gravimetric and titrimetric methods are somewhat more precise than the instrumental methods in current use for drug analysis. The difference, however, is not statistically significant and the general equation, RSDR = 2 exp(1-0.5 log C), is also applicable to gravimetric and titrimetric methods above a concentration level of about C = 0.001 (0.1%).

Chemical Phenomena↗

PubMed1978

Comparison of titration results of diphtheric antitoxic antibodies obtained by means of Jensen's method and the methods of tissue cultures and haemagglutination.

In 33 human sera the determination of diphtheric antitoxic antibodies was performed in a double blind test using Jensen's method, the method of tissue cultures and the haemagglutination method. In the method of tissue cultures the antibody levels in the sera were determinated in the first and second experiment with the precision of +/- half dilution of the geometrical progression. In Jensen's method, the difference between the first and second measurements slightly exceeded +/- 1 dilution. In the haemagglutination method the error considerably exceeded the binary step dilution. In most cases, the determination fluctuated up to seven times the actual value. Differences among the mean values of examination results obtained by Jensen's method and the method of the tissue cultures are statistically insignificant. The differences between the haemagglutination method and both the other methods are statistically significant.

Analysis of Variance↗

PubMed1977

A rebreathing method for measuring carbon monoxide diffusing capacity. A supplement to the single-breath method.

A rebreathing method for measuring carbon monoxide diffusing capacity is described. The method can be used in patients whose vital capacity is too small, or whose cooperation is inadequate, for the single-breath method. The apparatus is simple and the same gas mixtures are used as for the single-breath method. The results obtained by the rebreathing method are similar to those by the single-breath method (80% of the results by the rebreathing method lie within 20% of the value by the single-breath method). The rebreathing method also provides a measurement of the functional residual capacity.

Carbon Monoxide↗

PubMed1990

Methods for measuring GFR with technetium-99m-DTPA: an analysis of several common methods.

Several commonly used scintigraphic methods of GFR measurement were evaluated. Forty-three adult patients with a wide range of ages and renal function were studied. The two-sample plasma method of Russell and the urinary method of Jackson were the most accurate methods overall. The one-sample plasma method of Russell, the volume of distribution method of Fawdry, and a terminal slope method were less reliable, especially at low (0-60 ml/min) GFRs. The renal uptake method of Gates correlated poorly to the standards at all GFR levels even when corrected for body surface area or blood volume. The Russell two point and Jackson urinary GFR's can be used as complementary techniques and are recommended as primary methods of scintigraphic GFR determination.

Adolescent↗