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At least 451 records · Page 25Linked to original sources
PubMed1981

Equations and nomogram for the relationship of human blood p50 to 2,3-diphosphoglycerate, CO2, and H+.

We describe a new method for tonometry of small amounts of blood (up to 0.25 mL) at known pO2, PCO2, and temperature, in small, reusable, closed Pyrex flasks. Equilibrated blood is analyzed for oxygen saturation, pH, and organic phosphate concentration with standard techniques, and its p50 (the pO2 at which hemoglobin is half-saturated with oxygen) is determined with full control of all the variables known to affect it. The SD in the measurement of p50 is 0.044 kPa (0.33 mmHg). We made 63 determinations of p50 on normal human blood under different conditions of pH and pCO2, and with different concentrations of 2,3-diphosphoglycerate and ATP. Empirical equations and a nomogram were derived, which allow the calculation of p50 from known values of pCO2, pH, and [2,3-DPG]/[Hb4] molar ratio with a SD of 97 and 114 Pa (0.73 and 0.86 mmHg), respectively.

2,3-Diphosphoglycerate↗
PubMed1983

A nomogram for the determination of "virtual shunt" with correction factors for variations in pH, temperature and hemoglobin concentration.

Several nomograms are currently in use for determination of virtual shunt from a known FIO2 and PaO2. They are constructed for fixed standard values of pH, T and Hb. In the critically ill however those values often vary widely from the standard values. This may lead to substantial under- or overestimation of the virtual shunt. We therefore calculated correction factors resulting in a more precise value for the virtual shunt.

Body Temperature↗
PubMed1982

[Nomograms developed for determining the acid-base and oxygen status of cattle].

Investigations were carried out on a total of 66 lactating cows in order to work out an Octane nomogram for the direct recording of the PO2/HbO2 interrelationship and determine the normal alkali-acidic range in cattle. It is stated that these studies have made it possible to speculate on the clinical veterinary normal values of each particular index of the alkali-acidic balance and its prompt calculation.

Acid-Base Equilibrium↗
PubMed1981

A circumvaginal muscle nomogram: a new diagnostic tool for evaluation of female sexual dysfunction.

Female orgasmic capacity was previously shown to vary significantly with the condition of the pubococcygeus muscle as evaluated by an extensive digital examination and readings from a perineometer, a pressure sensitive device inserted into the vagina. Subsequently, a discriminant analysis was applied to 6 types of perineometer readings to determine if an optimal combination of readings could alone serve as an accurate evaluation of muscle condition. Initial strength resting and initial strength contracting predicted "good" versus "bad" muscle with 73.4% accuracy. A nomogram is presented for clinical use.

Female↗
PubMed1995

[A nomogram of duplex ultrasound quantification of peripheral arterial stenoses. Studies of the cardiovascular model and in angiography patients].

BACKGROUND AND METHODS: Blood flow velocity measurements were performed with duplex ultrasound in vitro (flow phantom) and in 62 patients who underwent angiography due to peripheral vascular disease. RESULTS: Intrastenotic peak systolic velocity (PSV) divided by proximally recorded PSV (peak velocity ratio, PVR) exhibited a strong correlation with percent diameter reduction: r2 = 0.86; N = 106 stenoses. A PVR value > or = 2.4 indicated a more than 50% stenosis with a sensitivity of 87% and a specificity of 94%. Calculation of PVR may normalize for patient variation and allow noninvasive quantification of lumen narrowing with high sensitivity and specificity. The intraobserver variability (95% CI) of stenosis quantification using PVR values was 10%. A nomogram simplifies estimation of lumen narrowing after measurement of intrastenotic and proximal PSV values. CONCLUSION: Quantification of peripheral artery stenoses can be performed easily and noninvasively with duplex ultrasound using the peak velocity ratio (PVR).

Aged↗
PubMed1995

[Uroflowmetric nomogram in the adult population of Canary Islands].

In order to know the uroflowmetric values of our healthy population, a uroflowmetry was made to 214 healthy subjects of both sexes. 75% of our group of volunteers collected mictional volumes under 300 ml. with no differences either by age or sex. The corresponding nomograms, in the form of percentile, for peak and mean flow in both sexes, were created. We found a progressive increase of peak and mean flow values with regard to mictional volume. Time to peak flow is shorter in women than in men. Volume at peak flow represents under 50% of total mictional volume. No significant differences in the uroflowmetric data of our healthy population and those from Anglo-Saxon authors was found.

Adult↗
PubMed1996

Rapid heparin anticoagulation: use of a weight-based nomogram.

The rapidity with which heparin anticoagulation is achieved is essential to a positive clinical outcome in patients with deep venous thrombosis or pulmonary embolus. However, adequate anticoagulation is frequently not achieved, either as a result of dosing regimens that do not take heparin kinetics into account or because of clinicians' wariness of possible hemorrhagic complications associated with elevated activated activated partial thromboplastin times. Obese patients are at particularly greater risk for subtherapeutic heparin dosing because their pharmacokinetic volumes of distribution differ from those in nonobese patients. Traditional empiric heparin dosing schemes may have pitfalls; methods that take into account the patient's weight are more likely to allow rapid anticoagulation. A nomogram that uses pharmacokinetic and volume of distribution principles to predict therapeutic levels of anticoagulation is presented.

Anticoagulants↗
PubMed1996

[The study of urinary flow in 3 to 14 year-old children. Urinary flow rate nomograms].

A descriptive analysis of 1361 uroflowmetries carried out in healthy children of both sex aged 3 to 14 years is reported. Maximal flow rate (Qmax), average flow rate (Qave), flow time (tQ), and maximal flow time (tQmax) are expressed as a function of body surface (sc) and urinary output volume. It is found that tQ increases as the urinary output volume does and decreases as sc becomes greater, tQ values being higher in males. Qmax and Qave are higher in females and run parallel to sc and urine volume. Comparison between both sex shows significant differences in Qmax values. Study of urinary flow curves reveals a normal pattern in more than 90% of samples. A percentile nomogram is developed for Qmax and Qave as a function of urinary output volume, sex and body surface.

Adolescent↗
PubMedDate not supplied

Introduction of partographic records in a District Hospital in Zambia and development of nomograms of cervical dilatation.

Partographic records of labour have been successfully introduced in a district hospital in Zambia. Nomograms of cervical dilatation show no significant difference compared to those obtained by other workers in other parts of the world. There was no difference in the duration of the active phase of the 1st stage of labour between multiparous patients (para 1--4) and grand multiparous patients (para greater than 4).

Cervix Uteri↗
PubMed1977

[Prevision of the hazard of acute carbon monoxide poisoning. A nomogram for calculating blood HbCO on the basis of the carbon monoxide concentration in air, the length of exposure and the lung ventilation (author's transl)].

The kinetics of carbon monoxide absorption was studied by the authors. An equation is proposed which enables to define the percentage of blood HbCO on the basis of the CO concentration in the air, the length of exposure, and the lung ventilation. The results proved to be satisfactory and were found to be comparable to the experimental data reported in the literature. A set of nomograms is reported which enables to define the blood HbCO saturation on the basis of the parameters which it depends on, therefore appearing to be very profitable to the physician in order to foresee and then prevent the hazard of acute carbon monoxide poisoning.

Air Pollution↗
PubMedDate not supplied

[The use of correction factors in establishing the time of death at the site where the corpse was found with the help of the nomograms of C. Henssge].

Assessment of the time of death (TD) at the site where the corpse is found is a most difficult task. Use of the method proposed by C. Henssge based on the use of special nomograms holds good promise. Our purpose was to derive the allowance coefficients which will extent the range of applications of this method. The research sample consisted of 156 cases. For each case we knew the ambient temperature at the site of the accident at the level of the corpse (which varied from -2 to +31 degrees C) and rectal body temperature (from +12 to +37 degrees C). The time of death was estimated with an accuracy of up to 15-30 min and varied from 2 to 22 h before investigation.

Autopsy↗
PubMed1998

Nomograms to follow recovery rate in status asthmaticus in a veteran population.

Data from 12 Department of Veterans Affairs patients hospitalized for status asthmaticus were analyzed to determine the rate and degree of response to therapy. The time to achieve recovery was directly related to the level of baseline obstruction at the time of hospital admission. The recovery rate was constant and could be described by a single second-degree polynomial regression equation. Nomograms were constructed showing this rate of improvement of pulmonary function over time at four levels of baseline pulmonary obstruction.

Aminophylline↗
PubMed1998

Nomogram of nuchal fold thickness of Thai fetuses.

The aim of the study was to establish normal values of nuchal fold thickness during 14-21 weeks of pregnancy. Three hundred Thai pregnant women before 12 weeks of gestation were recruited. Gestational age was determined by last menstrual period and confirmed by crown-rump length. Subjects with date-size discrepancy of more than 7 days were excluded from the study. Nuchal fold thickness was measured twice, first during 14-17 weeks, and then during 18-21 weeks. Five hundred and nine measurements were obtained. Nomogram of nuchal fold thickness was constructed. Mean values of nuchal fold thickness increased steadily from 2.59 +/- 0.77 millimeters (mm) at 14 weeks to 4.12 +/- 0.98 mm at 21 weeks. Average rate of increase were 0.22 mm per week. In conclusion, nuchal fold thickness increased with advancing gestational age from 14 to 21 weeks of pregnancy. Different normal cut-off levels for each gestational week may be more appropriate for screening of fetal Down syndrome in Thai pregnant women.

Down Syndrome↗
PubMed1976

Nomograms for obtaining a necessary, minimum sample size. II. When distribution of proportions from binomial data is approximately normal.

Two different nomograms corresponding to finite and infinite populations were devised to obtain a necessary, minimum sample size at a 95% confidence rate when the distribution of sample proportions calculated from binomial data was approximately normal. They could also be used for obtaining the 95% confidence limits of the population proportion from a sample proportion after having carried out a work.

Ecology↗
PubMed2026

Stretched penile length in boys with hypospadias: Population-based analysis using validated nomogram.

BACKGROUND: Hypospadias affects 1 in 200-300 male births. Parents are often concerned about penile adequacy beyond the urethral defect itself, yet few studies have systematically compared stretched penile length (SPL) in hypospadias against population-based reference standards. OBJECTIVE: To evaluate SPL distribution patterns in boys with Types I and II hypospadias and compare them with established normative data. METHODS: The authors studied 876 consecutive boys aged 1-14 years with unoperated Types I (distal) and II (mid-shaft) hypospadias. Two observers independently measured SPL using the validated SPLINT technique. The SPL measurements were compared against age-matched normative data from 1276 Indian children. Exact binomial probability tests were used for percentile distributions, chi-square tests for subtype comparisons and t-tests for mean deviations. RESULTS: The cohort included 479 Type I and 397 Type II cases. SPL distribution showed a marked leftward shift: 71% fell below the 50th percentile (expected 50%, p < 0.001) and 41.5% below the 25th percentile. Lower percentiles were overrepresented, 20.7% were below the 10th percentile and 20.8% in the 10th-25th range. Upper percentiles were depleted: only 7.4% in the 75th-90th range and 1.7% above the 90th percentile (all p < 0.001). Mean SPL was reduced by 6.8% (95% CI: -8.18 to -5.42%) in Type I and 7.5% (95% CI: -9.05 to -5.92%) in Type II. The two subtypes showed no significant distributional difference (&#x3c7;2 = 6.22, p = 0.18), suggesting that meatal position does not predict SPL reduction. CONCLUSIONS: Boys with distal and mid-shaft hypospadias show clinically meaningful SPL reduction that follows a continuous distribution rather than an all-or-none pattern. SPL reduction appears independent of meatal position. These findings support routine SPL assessment using population-specific references and can guide preoperative counselling.

Humans↗