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Results for “quantitative analysis”

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PubMed1978

The cranial base in fetal Macaca nemestrina: a quantitative analysis of size and shape.

The applicability of Fourier analysis to quantitate the midsagittal cranial base has been demonstrated utilizing fetal Macaca nemestrina. This methodology accurately measures the irregular form of the endocranial profile, minimizes the effects of size, and maximizes shape differences. This method provides a quantitative dimension to the descriptive analysis of shape change previously observed with a combined histologic and cephalometric analysis.

Animals↗

PubMed1990

[Non-quantitative analysis of the renography using 99mTc-DTPA; clinical efficacy and limitation].

The purpose of this paper is to evaluate the efficacy and limitation of the non-quantitative analysis of renography using 99mTc-DTPA, and to determine the clinical indication of the quantitative analysis of the study. We evaluated the clinical records of the patients and the findings of dynamic imagings and renograms. The non-quantitative analysis of the examination seemed to be useful to the selected cases, and quantitative analysis appeared to be dispensable except for the cases to evaluate the grade of parenchymal damages and causes of asymptomatic hematuria.

Adolescent↗

PubMed1978

Microchromatography of hemoglobins. VIII. A general qualitative and quantitative method in plastic drinking straws and the quantitative analysis of Hb-F.

The microchromatographic procedure for the quantitative analysis of the hemoglobin components in a hemolysate uses columns of DEAE-cellulose in a plastic drinking straw with a glycine-KCN-NaCl developer. Not only may the method be used for the quantitative analysis of Hb-F but also for the analysis of the varied components in mixtures of hemoglobins.

Chromatography, DEAE-Cellulose↗

PubMed1989

Quantitative analysis of autoradiograms.

Quantitative autoradiography of macroscopic specimens using computer-assisted image analysis is now widely used for studying the distribution of peptide receptors in the brain and peripheral tissues and more recently has been used to measure mRNA in tissue sections by in situ hybridisation. The spatial distribution of radiolabelled substances in tissue can be detected by the blackening of the emulsion in sheets of radiation-sensitive film and the resulting pattern of optical densities within the autoradiogram can be quantified by comparison with a calibrated radioactive scale. In this review, the technique of computer-assisted densitometry is described together with guidelines for the selection and preparation of radioactive standards. Strategies are discussed for ensuring that radioactivity can be measured and quantified using film-based emulsions with a precision approaching that of conventional counting techniques.

Animals↗

PubMed1986

Quantitative analysis of immunoglobulin-containing cells in gastrointestinal pathology.

The morphometric quantitative analysis of immunoglobulin-containing cells in gastrointestinal biopsies was explored as a possible additional parameter in making the histologic diagnosis of gastrointestinal diseases. Determination of immunoglobulin-containing cells was useful in the differential diagnosis of small intestinal disorders and may be useful in inflammatory diseases of the colon. However, before its general application in diagnosing inflammatory diseases of the colon can be advocated, prospective studies are necessary to determine the specificity and sensitivity of the quantitative analysis of immunoglobulin-containing cells in individual cases of large bowel disease.

Biopsy↗

PubMed1992

Oscillations in glycolysis: multifactorial quantitative analysis in muscle extract.

A multifactorial quantitative analysis of oscillations in glycolysis was conducted in the postmicrosomal supernatant of rat muscle homogenates incubated in the presence of yeast hexokinase. Oscillations in adenine nucleotides, D-fructose 1,6-bisphosphate, triose phosphates, L-glycerol 3-phosphate, 3HOH generation from D-[5-3H]glucose, NADH and L-lactate production were documented. The occurrence of such oscillations were found to depend mainly on the balance between the consumption of ATP associated with the phosphorylation of D-glucose, as catalyzed by both yeast and muscle hexokinase, and the net production of ATP resulting from the further catabolism of D-fructose 6-phosphate, as initiated by activation of phosphofructokinase. The oscillatory pattern was suppressed in the presence of D-fructose 2,6-bisphosphate. It is proposed that the quantitative information gathered in this study may set the scene for further studies in extracts of cells other than myocytes, e.g. hepatocytes and pancreatic islet cells, in which no oscillation of glycolysis was so far observed.

Adenine Nucleotides↗

PubMed1987

Quantitative analysis of NMR spectroscopic imaging.

A quantitative analysis of recovery curves derived from a series of standard and spectroscopic images is presented. Inversion recovery sequences were modified to produce difference (W-F) images of a water and fat phantom. Adding and subtracting these data from those obtained from standard inversion recovery images resulted in separate recovery curves for the fat and water fractions of emulsions making up the phantom. The procedure yielded consistent reproducible values of longitudinal relaxation times for the constituents of the emulsions.

Emulsions↗

PubMed1991

[Quantitative analysis of signal-averaged electrocardiograms].

Quantitative analysis of the high frequency components of the terminal portion of the high-resolution surface QRS was performed in 119 normal subjects (N), 62 patients with ventricular tachycardia (VT) including 20 patients with sustained VT or VF (VTs/VF) and in 565 ischemic and nonischemic cardiac patients (NO-VT). High-resolution surface ECG (SAECG) was obtained during sinus rhythm with noise level below 0.4 microV by ART-1200EPX. The vector magnitude of the filtered and signal-averaged standard bipolar orthogonal leads X, Y, Z (V = square root of X2 + Y2 + Z2) were used for analysis. Total duration of the QRS (QRST), the duration of the low amplitude (40 microV) signals in the terminal portion of the QRS (D40) and the amplitude of the signals in the last 40 ms (V40) were measured at filter settings of both 25Hz and 40Hz by the computer. Specific values for each of the indices were identified at both 25Hz and 40Hz filterings, which could separate N as well as NO-VT from VTs/VF. They were greater than or equal to 120 ms for QRST, greater than or equal to 34 ms for D40 and less than or equal to 25 microV for V40 at 25Hz, greater than or equal to 120 ms for QRST, greater than or equal to 39 ms for D40 and less than or equal to 20 microV for V40 at 40 Hz filtering.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

Availability and limitations of thallium-201 myocardial SPECT quantitative analysis: assessment as daily routine procedure for ischemic heart disease.

To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia.

Aged↗

PubMed1987

[A method for the quantitative analysis of steroid hormones by HPLC/RIA].

To solve the problem of cross-reaction in immunoassay and determine various steroid hormones simultaneously in a small amount of sample, a method for the quantitative analysis of steroid hormones was developed. This method is a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay (RIA). The purpose of the study is the comprehensive analysis of steroid hormones profiles in normal subjects and adreno-cortical diseases. One hundred microliters of plasma was extracted by ether and the ether layer was evaporated. The residue was redissolved and separated by HPLC. Then fractions of steroid hormones were taken and determined by RIA. In this study, cortisol (F), androstenedione (A), 17 alpha-hydroxyprogesterone (17-OHP), testosterone (T), progesterone (P), estrone (E1) and estradiol (E2) were analyzed in normal adults, congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency and Cushing's syndrome. Results in normal adults were similar with those had been previously reported. In CAH, F was remarkably low and 17-OHP, A, T and P were remarkably high before treatment. During treatment some cases showed that 17-OHP, A, T and P were high, and 17-OHP and P tended to be within normal range, if F had been kept higher than about 20 micrograms/dl. In the analysis of Cushing's syndrome before treatment, there were definite differences between adenoma and hyperplasia. A, 17-OHP, T, E1 and E2 were higher in hyperplasia than those in adenoma. It is suggested that it is possible to diagnose the type of Cushing's syndrome with a small amount of plasma using this method. As a mass screening method of CAH at present, 17-OHP in dried blood on filter paper is determined, therefore the quantitative analysis of 17-OHP in dried blood on filter paper (9 mm disc) was attempted. The quantitative analysis proved to be possible, and it was considered to be applied as the secondary screening method of CAH by the use of dried blood on filter paper.

Adrenal Cortex Hormones↗

PubMed1990

Secondary structure of the ribosome binding site determines translational efficiency: a quantitative analysis.

We have quantitatively analyzed the relationship between translational efficiency and the mRNA secondary structure in the initiation region. The stability of a defined hairpin structure containing a ribosome binding site was varied over 12 kcal/mol (1 cal = 4.184 J) by site-directed mutagenesis and the effects on protein yields were analyzed in vivo. The results reveal a strict correlation between translational efficiency and the stability of the helix. An increase in its delta G0 of -1.4 kcal/mol (i.e., less than the difference between an A.U and a G.C pair) corresponds to the reduction by a factor of 10 in initiation rate. Accordingly, a single nucleotide substitution led to the decrease by a factor of 500 in expression because it turned a mismatch in the helix into a match. We find no evidence that exposure of only the Shine-Dalgarno region or the start codon preferentially favors recognition. Translational efficiency is strictly correlated with the fraction of mRNA molecules in which the ribosome binding site is unfolded, indicating that initiation is completely dependent on spontaneous unfolding of the entire initiation region. Ribosomes appear not to recognize nucleotides outside the Shine-Dalgarno region and the initiation codon.

Base Sequence↗

PubMed1987

Characterization of tissue and plasma glycosaminoglycans during experimental AA amyloidosis and acute inflammation. Qualitative and quantitative analysis.

Qualitative and quantitative methods were used to determine changes in glycosaminoglycans (GAGs) in the spleen and plasma during initial stages of experimental amyloidosis and acute inflammation. GAG deposition in the spleen during the early stages of amyloidosis consists of a 16-fold heparin and heparan sulfate increase. Though splenic weights do increase during protracted inflammation only minor changes arise in splenic GAGs in the absence of amyloid deposition. An overall increase in plasma GAGs, consisting of a 4.5-fold chondroitin-4-sulphate increase, occurred at the time of GAG deposition in the tissues (spleen, liver) and probably accounts for the minor GAG changes seen in the spleen during inflammation. The time course of splenic heparin/heparan sulfate increase during amyloid deposition coincides with the histochemical changes previously described. Plasma GAG changes follow a pattern similar to that of acute phase protein reactants. The results suggest that GAG metabolism, in particular heparin/heparan sulfate, are intimately involved in the process of AA amyloidogenesis.

Acute Disease↗

PubMed1986

Noninvasive identification of left main and triple vessel coronary artery disease: improved accuracy using quantitative analysis of regional myocardial stress distribution and washout of thallium-201.

The capabilities of visual and quantitative analysis of stress redistribution thallium-201 scintigrams, exercise electrocardiography and exercise blood pressure response were compared for correct identification of extensive coronary disease, defined as left main or triple vessel coronary artery disease, or both (50% or more luminal diameter coronary narrowing), in 105 consecutive patients with suspected coronary artery disease. Extensive disease was present in 56 patients and the remaining 49 had either less extensive coronary artery disease (n = 34) or normal coronary arteriograms (n = 15). Although exercise blood pressure response, exercise electrocardiography and visual thallium-201 analysis were highly specific (98, 88 and 96%, respectively), they were insensitive for identification of patients with extensive disease (14, 45 and 16%, respectively). Quantitative thallium-201 analysis significantly improved the sensitivity of visual thallium-201 analysis for identification of patients with extensive disease (from 16 to 63%, p less than 0.001) without a significant loss of specificity (96 versus 86%, p = NS). Eighteen (64%) of the 28 patients who were misclassified by visual analysis as having less extensive disease were correctly classified as having extensive disease by virtue of quantitative analysis of regional myocardial thallium-201 washout. When the results of quantitative thallium-201 analysis were combined with those of blood pressure and electrocardiographic response to exercise, the sensitivity and specificity for identification of patients with extensive disease was 86 and 76%, respectively, and the highest overall accuracy (0.82) was obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1975

Quantitative analysis of the carotid sphygmogram in atherosclerosis.

A study has been made, by means of quantitative analysis, of the changes in the CSG of 355 persons-131 healthy, 112 with ischemic heart disease and 112 with hypertension. The quantitative analysis includes: (1) coefficient of declination, pointing to the declivity of the anacrotic limb; (2) coefficient of propulsion, pointing to the time of formation of the maximum peak and (3) level of indentation, pointing to the height of the valve notch. These 3 indices regularly increase along with progressive induration of the arterial wall and serve as quantitative criteria for a more accurate differentiation of the separate types of CSG used in clinical practice.

Adolescent↗

PubMedDate not supplied

A quantitative analysis of the afferent innervation of the organ of corti in guinea pig.

A quantitative analysis of the afferent innervation of the organ of Corti was made on normal and vestibular nerve-sectioned guinea pigs. Section of the vestibular nerve at the internal auditory meatus provided an efficient means of eliminating the efferent innervation to the cochlea without significant loss of afferent fibres. Nerve counts on normal and de-efferented animals revealed that about 10-15 % of the cochlear afferent innervation supplies the outer hair cells. The remaining 85-90% of afferent fibres innervate the inner hair cells. As in cats, all tunnel spiral bundle fibres and upper tunnel crossing fibres were efferent to outer hair cells. Since unmyelinated fibres in the osseous spiral bundle were not counted, quantitative analysis of the efferent innervation to inner hair cells could not be made. However, a significant loss of myelinated fibres in the osseous spiral lamina after vestibular nerve section confirms that many myelinated efferent fibres are present in this region.

Animals↗

PubMed1990

[Quantitative analysis of background activity using ambulatory EEG monitoring system].

We studied a possibility of the quantitative analysis of background activities using ambulatory EEG monitoring system (AEEG). (1) This recorder system had a stable frequency characteristics from 1.0 Hz to 20 Hz, in which range the background activities on EEG were organized, and also had a good lineality of amplitude until 150 microV. Therefore, this system had no hindrance in quantitative analysis of EEG background activities. (2) We selected the method of continuous spectrum array (CSA) to analyse the records using AEEG. The CSAs at awakening, light sleep and deep sleep respectively revealed the characteristic patterns of spectrum. And, in the long-term examination of CSA during sleep, the dynamic alternation of spectrum was well recognized depending on the change of sleep stages. This method was useful to the evaluation of sleep cycle as well as the judgement of consciousness level. The AGGE has many advantages compared with the other long-term EEG systems. Major advantages are as follows: 1) The patient can move freely with this equipment. 2) A whole day's record can be stored on a cassette. 3) The operative technique is easy. The clinical and research application of AEEG may be more expanded to combine with the various computer analysing methods.

Electrocardiography, Ambulatory↗

PubMed1985

Improved reproducibility and quantitative analysis of phospholipids by flame ionization detection.

Quantitative analysis of phospholipids by flame ionization was improved by careful application of samples with a Hamilton syringe and use of a sealed dual tank system. Chromarods developed more consistently with reproducible scanning times or RF values (coefficient of variation of 1%) and with sharper peaks if development was carried out in a sealed dual tank system. The Chromarods were placed in the inner tank, which was the standard ground glass topped tank furnished with the Iatroscan TH-10 system. This inner tank was placed inside a larger thin-layer chromatography tank which was sealed with silicone grease and the lid held in place with a lead brick. Both tanks were lined with absorbent paper and contained the same solvent system. Biological samples quantified with these procedures and measured in amounts between 1 and 30 micrograms had coefficients of variation between 0.2 and 6%. An efficient method of completely separating neutral lipids from phospholipids and allowing quantitative determination of cholesterol is described. Scanning times and RF values of various phospholipids are compared to determine the best separation of the major phospholipids found in 3T3-L1 and leukocyte membranes.

Cell Membrane↗

PubMed1992

Quantitative analysis in single photon emission tomography (SPET).

Quantitative analysis can improve the sensitivity and specificity of single photon emission tomography (SPET) procedures, as well as reduce inter- and intraobserver variabilities. Quantification of the radioactivity distribution is the ultimate goal of SPET. In this review we consider the basic requirements for an optimum three-dimensional reconstruction of the radionuclide distribution to enable quantification. Attenuation and scatter correction as well as varying resolution are the major problems. In the older SPET systems quantification was hampered by the lack of system sensitivity and sufficient computer power. Therefore, the imaging system was often assumed to be shift invariant and linear and the attenuation throughout the object uniform. More sophisticated solutions have been proposed and with more or less success implemented, but not for application in daily practice. Knowledge (measurement) of the attenuation is often required. New generation SPET systems employing multi-detectors and super minicomputers will ease the implementation of these solutions.

Humans↗