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PubMed1996

Reference values for pulmonary function tests of Japanese-American men aged 71 to 90 years.

Pulmonary function was assessed by spirometry in 3,076 elderly Japanese-American men of the Honolulu Heart Program (HHP) cohort. The assessment was done with a stringent quality assurance program that adhered to American Thoracic Society (ATS) recommendations for spirometry. Less than 6% of the participants were unable to perform three acceptable spirometry maneuvers. A "healthy" subgroup of 528 men between the ages of 71 and 90 yr was identified by excluding almost all smokers and subjects with lung disease and other factors negatively influencing FEV1. Reference equations and normal ranges for FEV1, FVC, and the FEV1/FVC ratio were derived from the healthy group. Use of prediction equations from the Cardiovascular Health Study (CHS) of elderly European-American men consistently overpredicted FVC by 0.3 to 0.4 L and FEV1 by 0.15 L. Men in the HHP were on average 11 cm shorter than those in the CHS. Use of a prediction equation derived from the HHP cohort when the men in the cohort were on average 22.6 yr younger consistently overpredicted FEV1 by 0.2 to 0.3 L. These results underscore the importance of using prediction equations appropriate to the ethnicity, age, and height characteristics of the subjects being studied.

Aged↗
PubMed1981

Reference values for erythrocyte acetylcholinesterase and plasma cholinesterase activities in children, implications for organophosphate intoxication.

Acetylcholinesterase and cholinesterase activity was measured in the blood of both healthy children 0-12 years of age and adults by a recently developed radiochemical method. Children less than 4 months of age were found to have lower levels for these enzymes than adults. Above this age, however, similar values were obtained for children and adults. A case report of an organophosphate intoxication is presented and is discussed in the light of our results.

Acetylcholinesterase↗
PubMed1981

Reference values of renal excretion of fluoride.

Fluoride was measured in the spontaneous urine of a group of persons (n = 397) occupationally non-exposed to fluoride. At a concentration less than 2 . 10(-4) g/kg fluoride in drinking water the mean fluoride excretion in urine is 0.61 mg/l F with an upper limit of 2.00 mg/l F. The 95-percentile of normal fluoride excretion is 1.0 mg/l F. By correcting the values for the specific gravity of 1.024 the mean value of the fluoride excretion is 0.74 mg/l F with an upper limit of 3.9 mg/l F. The measured pH and calcium contents had no influence on the fluoride excretion.

Adolescent↗
PubMed2004

Intraindividual reference values.

When a biological quantity examination exhibits a high degree of individuality, developing a strategy for interpreting these values in an individual context can be a useful alternative. Time-series analysis is the appropriate statistical framework to build a model for explanation of the behaviour of laboratory information and to forecast future values. The key concepts in this approach are autocorrelation and within-person variance. Unfortunately, the powerful tools provided by time-series analysis require many observations, a requisite difficult to meet in every day practice. However, introducing some restrictions in the autocorrelation parameter of the most reliable model, the first order autocorrelation model, and using the average within-person variance from a selected population, it is possible to build predictive reference intervals for an individual, based on only few observations. The most common case is the minimum time series: when there are just two observations. The statistical significance of the change from a previous observation is a problem that arises from both quality control (delta checks) and the interpretative diagnostic fields (reference change limit). Applying the same restrictive criteria, it is possible to develop specific limits for a difference between consecutive observations based on a within-person variance selected from the distribution of variances found in a sample of similar individuals.

Forecasting↗
PubMed1984

[Urinary alanine aminopeptidase excretion in children: reference values and effect of nephrotropic contrast media].

The catalytic activity of alanine aminopeptidase (EC 3.4.11.2) in urine shows a clear cut difference between boys (1530 mU/d X m2) and girls (1143 mU/d X m2). Nineteen children (preterms to 14 years) received contrast media (loxaglate (Hexabrix) (N = 15) or lotalamate (Conray 70) (N = 4] according to the diagnostic indication. The alanine aminopeptidase activity increases to 10-fold of the initial value in the loxaglate and 19-fold of the initial value in the lotalamate group. These results demonstrate a much higher response of the kidney to contrast medium in children than in adults.

Adolescent↗
PubMed1981

Reference values for ionized, complexed, and protein-bound plasma magnesium in men and women.

Of the three magnesium fractions in plasma, free ionized magnesium (Mg2+) has the greatest biological activity. Accordingly, information concerning this form in plasma is of cardinal importance to investigations in biometry and human pathology. For this reason, we developed an indirect assay for ionized magnesium in which Mg2+ is determined as the difference between ultrafiltrable magnesium, as measured in plasma water after ultracentrifugation, and complexed magnesium, as obtained after fixation of the ionized and protein-bound magnesium on Amberlite IR-120(H) cation-exchange resin. All magnesium assays were performed by atomic absorption spectrometry. We used this methodology to compare ionized, complexed, and protein-bound plasma magnesium in 34 normal men and 12 normal women. Sex-related differences between the values for these fractions were not significant. Interesting preliminary results for cases of myocardial infarction prompt us to continue our investigations concerning these three states of plasma magnesium in cardiac pathology.

Adult↗
PubMed1992

Reference values of maximal respiratory mouth pressures: a population-based study.

The aim of our study was to measure values of maximal inspiratory (MIP) and expiratory (MEP) mouth pressures in 625 (266 male, 359 female) clinically and functionally normal subjects drawn out of a sample representative of the general population. MEP (near TLC and FRC) was found to be significantly higher when compared with MIP (near RV and FRC), and pressures in male subjects were significantly higher than those in female subjects. MEP values at TLC and FRC were found to be closely related, as were values of MIP near RV and near FRC. Among the tested body-size variables, body surface area (BSA) for all parameters had the highest degree of correlation. Stepwise linear regression analysis was performed to define the equation of normality for all four parameters, employing BSA, sex, age, and relative interaction terms. R2 values, although the variables employed for the equations were highly significant, were relatively low and didn't fully explain the source of variability. The influence of age was smaller than the influence of BSA, although age did reduce the unexplained variance in MEP and MIP. These results confirm that the most useful employment of MIP and MEP is to monitor their changes in each patient, but they point out, however, the usefulness of reliable reference equations.

Adolescent↗
PubMed1997

Reference values for height, height velocity and weight in Turner's syndrome. Swedish Study Group for GH treatment.

As Northern Europeans are currently the tallest people in the world, specific growth charts for girls with Turner's Syndrome from this area are needed. Based on height and weight measurements from 598 girls with Turner's Syndrome (372 from the Netherlands, 108 from Denmark, 118 from Sweden) not treated with growth-promoting substances and without signs of spontaneous puberty, we constructed growth charts for height-for-age, height-velocity-for-age, weight-for-age, weight-for-height and Body Mass Index for age. Reference tables and regression equations for mean and standard deviation are provided allowing calculation of Standard Deviation Scores. The height and height velocity curves show a low birth length, gradual deviation from the normal percentile curves without pubertal growth spurt, and a prolonged growth until the early 20s. Mean adult height was 146.9 +/- 7.8 cm. Mean weight-for-age was lower than in normal reference children but height-adjusted weight was higher, except in infancy and early childhood. Further studies are required on the factors influencing the weight-height relationship in Turner's Syndrome.

Adolescent↗
PubMed1978

Metabolic and cellular profile testing in calves uncer feedlot conditions: blood cellular components--reference values and changes over time in feedlot.

The cellular components of the blood of 114 calves were measured under feedlot conditions. The results suggest that certain cellular components of the blood of a group of crossbred feedlot-type calves which are homogeneous only with regard to weight are reasonably uniform. More specifically, all red blood cell components have coefficients of variation of less than 10%. The white blood cell counts underwent drastic changes over the first 2 sampling dates, ie, before and after transport and processing of the calves. Later, in the feeding period, the cell counts readjusted to more stable levels. The results were compared with such values obtained from dairy cattle. The total erythrocyte count, total leukocyte count, and red blood cell components were found to be slightly higher in these feedlot calves than in dairy cattle. The difference might partly be due to age. The mean values reported can be used as a base for comparison with values obtained from other such studies or from studies of disease processes in cattle under feedlot conditions (or both).

Animal Feed↗
PubMedDate not supplied

[Reference values for blood levels of free thyroxine, free triiodothyronine and thyroxine-binding globulins in euthyroid children. Method: luminescence-enhanced enzyme immunoassay].

Concentrations of free thyroxine (n = 296, male 164, female = 132), free triiodothyronine (n = 273, male 156, female = 117) and thyroxine-binding globulin (n = 273, male 156, female = 117) were determined using the luminescence enhanced enzyme immunoassay method in blood-serum of euthyroid children. Beyond the 30, day of life no significant differences were found in different age groups for the free thyroxine and beyond the 2, day of life for the free triiodothyronine concentration. The free thyroxine values of the infants in the range of 15-39 pg/ml decreased to the range of 9-18.5 pg/ml and the free triiodothyronine values decreased from 3.4-9.3 pg/ml to the range of 2.8-6.5 pg/ml. The values for thyroxine-binding globulin increased in the first month of life up to the range of 18-35 mg/l and decreased afterwards continuously to the range of 14.5-26.5 mg/l.

Adolescent↗
PubMed1995

Technetium-99m mercaptoacetyltriglycine clearance: reference values for infants and children.

Six hundred and thirty-nine clearance studies performed in children aged 7 days to 19 years utilizing technetium-99m mercaptoacetyltriglycine (MAG 3) were retrospectively analysed. Standardized conditions for the investigation included: parenteral hydration (60 ml/hxm2 body surface) in addition to normal oral fluid intake, weight-related dose of 99mTc-MAG 3 (1 MBq/kg body weight, minimum 15 MBq) and calculation of clearance according to Bubeck et al. Of the 513 children, 169 included in this analysis could be classified as "normal" with regard to their renal function. Normal kidney function was judged by the following criteria: normal GFR for age, normal tubular function (absence of proteinuria and glucosuria), normal renal parenchyma (on ultrasonography, MAG 3 scan and intravenous pyelography), absence of significant obstruction and gross reflux (>grade I), no single kidney and no difference in split renal function >20%. Results showed increasing MAG 3 clearance values for infants during the first months of life, reaching the normal range for older children and adults between 7 and 12 months.

Adolescent↗
PubMed2001

[Reference values of growth hormone binding protein (GHBP) for a normal pediatric population].

UNLABELLED: Circulating concentrations of the high affinity growth hormone binding protein (GHBP) may be a marker of GH receptor density as well as GH sensitivity. GOAL: To determine values of GHBP for a normal Chilean pediatric population. METHODS: We determined GHBP levels in 73 males and 73 females between 4 to 15.5 years and 4 to 16.8 years respectively, divided in 7 groups according to age and puberal status. RESULTS: The population was normally distributed in weight, height and body mass index (BMI). GHBP activity increased up to Tanner IV in males and Tanner III in females, and decreased slightly thereafter in Tanner V and IV respectively. There was a significant difference between GHBP levels of preschool children and those found in Tanner II to V in both sexes (p < 0.05). In addition, we found a positive correlation between GHBP vs weight, height and BMI (p < 0.001) in males and females. CONCLUSION: The availability of this methodology allows us to establish the normative value of GHBP in our population and provides useful information to interpret GH circulating levels in children with growth disorders.

Adolescent↗
PubMed2006

Reticulocyte count, mean reticulocyte volume, immature reticulocyte fraction, and mean sphered cell volume in elite athletes: reference values and comparison with the general population.

BACKGROUND: The role of measurement of reticulocytes and their parameters is growing in sports medicine. The use of reticulocyte counts in protocols for evaluating and screening for the suspected abuse of hormones that stimulate the bone marrow is an example. Reticulocytes are also important for evaluation of the performance and general health status of athletes, especially for monitoring therapies and diets. The current availability of fully automated haematological systems that can measure reticulocyte numbers and characteristics (volume, density) increases the potential use of these parameters in laboratory and sports medicine. Few studies have considered the application of these parameters in athletes and a lack of specific reference ranges means that their valid clinical use is difficult. METHODS: Using a Coulter LH700 instrument, we measured reticulocyte count (Retics), mean reticulocyte volume (MRV), immature reticulocyte fraction (IRF), and mean sphered cell volume (MSCV) in 106 male professional elite athletes (football and rugby players and skiers). Reference intervals for the athletes were compared with the intervals found for a control group of 73 age-matched males. RESULTS: We calculated the following reference intervals: 0.30-1.54% for Retics, 93.1-114.8 fL for MRV, 0.18-0.39% for IRF, and 76.8-94.5 fL for MSCV. CONCLUSIONS: No statistically significant differences were observed for Retics, MRV, IRF, and MSCV between elite athletes and controls. Significant differences were observed for haemoglobin (Hb), erythrocytes, haematocrit (Ht), and mean corpuscular volume. Moreover, no statistical differences were observed among different sports, whereas differences were remarked in football and rugby players between the samples drawn before the start of competitive season and the samples drawn during the season, demonstrating that reticulocyte counts and parameters are useful for monitoring sportsmen.

Adult↗
PubMedDate not supplied

[Reference values of sodium, potassium, chloride, calcium, inorganic phosphate and magnesium levels in the cerebrospinal fluid of children].

Concentration of sodium, potassium, chloride, calcium, inorganic phosphate and magnesium was determined in cerebrospinal fluid of 155 children (ages 1 month - 16 years). On the basis of clinical criterions the children were considered to be "healthy". The total number of examined children was 2 500 (1978-1983). The statistical age- and sexspecific investigation of the results showed no significant differences. Compilation of the values resulted in a physiological concentration of sodium 132.3 +/- 17.6 mval/l, potassium 2,59 +/- 0.37 mval/l, chloride 113.1 +/- 15.5 mval/l, calcium 3.47 +/- 1.45 mval/l, inorganic phosphate 1.11 +/- 0.21 mg/dl and magnesium 2.60 +/- 0.46 mg/dl.

Adolescent↗
PubMed1992

[Reference values of QRS-complex amplitude parameters in computer evaluation of Frank's orthogonal electrocardiogram].

In 123 healthy subjects (54 women and 69 men) in the age range from 7 to 72 years the x, y, z coordinates were determined along with the magnitude of instantaneous spatial QRS vectors of the orthogonal electrocardiogram according to Frank, and that in 10 ms intervals from the beginning of the QRS complex and eighths of the duration of QRS. The values of these parameters were computed by means of Pipberger's VAH program implemented in the computer SM3-20. The results are presented as means, standard error of means, median, interpercentile interval (2 to 98 percentile) and confidence intervals.

Adolescent↗
PubMed1982

Metabolic and cellular profile of wether goats: protein fractions and lactate dehydrogenase isoenzymes- reference values.

Blood serum concentrations of electrolytes; mineral, serum protein, and biochemical components; serum lactate dehydrogenase (LDH) activity; and blood cellular components were determined in 8 wether goats over a 59-day feeding period. The blood was collected on 6 sampling days, the blood cellular components were analyzed on collection days. The biochemical components were analyzed from frozen samples approximately 3 weeks after collection. The serum protein fractions and LDH isoenzymes were separated electrophoretically from frozen samples. The purpose was to determine the variability and changes in these values, using sample-day intervals over the feeding period. The blood serum concentrations of many of the biochemical and blood cellular components that were measured or calculated varied considerably, showing fluctuations over some portion of the period and ending with an erratic peak at period's end. The WBC count, neutrophil, and band neutrophil values were sharply decreased on sampling days 24 and 35, followed by fluctuations over the last half of the period.

Alanine Transaminase↗
PubMed1985

Human kininogens of low and high molecular mass: quantification by radioimmunoassay and determination of reference values.

Kininogens of low and high molecular mass, highly purified from human plasma, were used to raise antisera in rabbits. To obtain immunologically intact tracers, we labeled the kininogens by the lodogen method, followed by double chromatography, first on Sephadex G50 and then on Sephadex G200 for high-molecular-mass kininogen or on G100 for low-molecular-mass kininogen. Both assays are sensitive, accurate, and reproducible. On an equimolar basis, the high-molecular-mass kininogen cross reacted completely in the determination of low-molecular-mass analyte. Moreover, the radioimmunoassay for the former was highly specific. After optimizing the time and temperature of incubation to provide rapid and reliable results, we determined 95% reference intervals from a large sample of healthy subjects (250 men, 200 women): 109-272 and 69-116 mg/L for the low- and high-molecular-mass kininogens, respectively.

Adult↗