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The differences of adult female murine mandibular form between two inbred strains of mice (BALB/cBy and C57BL/6By) were analyzed by use of the finite element method (FEM). In the present instance, this method overcomes the conceptual and methodologic constraints of both craniometry and roentgenographic cephalometry by providing two-dimensional, reference-frame-invariant, independent comparisons of the size, shape, and location of the point continua enclosed within the boundaries for each local, finite element into which the mandible was discretized. At the present scale of observation, it is suggested that the FEM kinematic descriptions of form comparisons can be correlated with dynamic interpretations offered by the functional matrix hypothesis, i.e., that certain discrete, causal relationships exist between the continuum form of single elements and the form, or function, of anatomic structures associated with these elements. It is concluded that, in addition to its previously demonstrated use in the analysis of growth, the finite element method seems well suited for comparisons of form.
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The prognostic value of subjective histological and morphometric grading was studied in 75 primary ovarian carcinomas. Histological grading methods recommended by Czernobilsky and by Russell and the morphometric method of Baak and co-workers were compared in a two-observer system. The 5-year survival could be correctly predicted in about two-thirds of the patients with all three methods. When mitotic counting (volume corrected mitotic index, M/V-index) was compared with the above grading methods by using a receiver operating characteristic curve) the M/V-index was generally superior in its prognostic power regardless of the sensitivity/specificity level chosen. The morphometric grading method and the grading method based on the M/V index were also shown to be readily reproducible.
Cerebral blood flow in both hemispheres was studied by the 133Xe inhalation method in 49 patients with cerebral infarction in the unilateral hemisphere. They were classified into three groups by computed tomographic findings as follows; relatively large low density lesion including the cerebral cortex and subcortex (cortical: C group), relatively large low density lesion including the subcortical white matter and basal ganglia (large subcortical: L group), and small low density lesion including the subcortical white matter (small subcortical: S group), respectively. Mean cerebral blood flow (mCBF) in the affected hemispheres was markedly low in C group, moderately low in L group, and slightly low in S group, in all of the examinations. Several cases in C and L groups revealed remarkable changes of mCBF less than one month after the onset. MCBF in both hemispheres was lower in C group than in L and S groups less than one week after the onset. Seven to twelve weeks after the onset, mCBF in the affected hemisphere was lower in C and L groups than in S group, and than in the unaffected hemisphere of C and L groups. There was no difference between mCBF in the affected hemisphere and that in the unaffected hemisphere in most of S group. Sequential changes of mCBF in both hemispheres were divided into seven types in 27 cases, who were examined first less than one week and repeatedly then. However, the sequential changes were classified roughly into two patterns.(ABSTRACT TRUNCATED AT 250 WORDS)
The nuclear DNA content was estimated in 2 microns sections of 18 lymphoma cases by two methods: (1) Feulgen densitometry using QTM 900 with correction by Bins' procedure which allows size-independent DNA distributions; (2) stereological unfolding as proposed by Cruz-Orive giving sphere-size distributions. A general correlation was found between results and DNA measurements obtained by imprint and flow cytometric techniques in the same specimens. When histologic DNA profiles were compared to cytologic histograms, a high correlation was found between the distribution of ploidy classes by correspondence analysis. However two highly proliferating lymphomas were erroneously classified as aneuploid. Conversely, sphere-size distributions allowed the identification of the majority of aneuploid lymphomas but failed to recognize proliferating ones. It appears that when cytologic specimens are not available, densitometric studies on sections may provide valuable information on DNA content, with complementary data obtained from stereological procedures.
The repeatability of weight estimation of cattle by scale and by tape and the agreement of weight estimates obtained by the 2 methods were evaluated. The within-subject standard deviation of replicates was used as a measure of repeatability while the agreement of the 2 methods was evaluated by analysis of the differences in weight estimates. In young cattle, the measurement error of the tape was about twice that of the scale while in adult cattle it was more than 4 times as great. Although weight estimates by the 2 methods were highly correlated, considerable differences occurred in individual cattle. The same was true for estimates of weight gain. It does not appear advisable to use the tape in trials where weight is an independent variable whereas the use of the tape can be justified in experiments where weight is the dependent variable.
Several connective tissues were stained for proteoglycans using the cationic dye Cuprolinic Blue according to the critical electrolyte concentration method. With this method, proteoglycans are visualized as electron-dense filaments. In most tissues, two types of proteoglycan filaments are present: a small (maximum length 60 nm), thin, collagen fibril-associated filament, and a thick, heavily-staining filament which is predominantly localized between bundles of collagen fibrils. Cartilage contains very large (about 300 nm) proteoglycan filaments while in cornea they are very small. Comparison with biochemical data from the literature suggests that the appearance of the proteoglycan filaments may be indicative for the glycosaminoglycan-protein ratio and for the molecular weight of the part of the protein core to which glycosaminoglycans are attached. The data thus obtained on the localization and structure of a proteoglycan may be useful when planning a strategy for its isolation.
The accuracy and reproducibility of indirect measurement of cardiac output at rest by the carbon dioxide rebreathing (indirect Fick) method with an automated respiratory analysis system (Gould 9000IV) were compared with simultaneous measurements made in duplicate by dye dilution and thermodilution in 25 patients having cardiac catheterisation studies. Measurements of cardiac output by the carbon dioxide rebreathing method were not significantly different from those obtained with dye dilution (mean difference -0.3 l/min, SD 0.76, 95% confidence interval -0.7 to 0.1). Thermodilution significantly over-estimated cardiac output by a mean of 2.2 l/min or 39% (SD 1.5, 95% confidence interval 1.6 to 2.8) compared with the carbon dioxide rebreathing method and significantly overestimated cardiac output by 1.9 l/min or 31% (SD 1.2, 95% confidence interval 1.2 to 2.5) compared with dye dilution. The reproducibility of measurements of cardiac output in individual patients was satisfactory with the dye dilution method but was poor with carbon dioxide rebreathing and thermodilution. Indirect measurement of resting cardiac output by the Gould 9000IV automated carbon dioxide rebreathing method is more accurate but the variability inherent with this method requires that multiple measurements be taken for each determination. Measurement of cardiac output by the thermodilution method by a commercially available cardiac output computer was not satisfactory because not only was there considerable variability between repeat measurements but the method also consistently overestimated cardiac output compared with the dye dilution method.
The present study compared abusive, potentially abusive, and control group parents' perceptions of commonly used discipline procedures. The clinical samples were obtained from Parents Anonymous (PA) and consisted of both court-referred (abusive) and self-referred (potentially abusive) members. The subjects were presented with case vignettes that described a child with either mild or severe behavior problems and asked to rate four methods of disciplining the child. The discipline methods involved positive reinforcement, timeout, timeout with spanking, and spanking. The findings indicated that (1) overall, the parents generally evaluated positive reinforcement as significantly more acceptable than timeout, timeout with spanking, and spanking; (2) self-referred PA members viewed timeout, timeout with spanking, and spanking as relatively more acceptable than did their demographically similar comparison group; and (3) court-referred PA parents' ratings did not significantly differ from their comparison group, since both groups rated the reinforcement method as significantly more acceptable than the other three discipline methods.
For the determination of CO2-content from incubation experiments infrared-absorption, interferometer and titration methods were compared with regard of the reproduction of experimental results. The data obtained by titration were general higher. The middle coefficients of variation amounted for infrared-absorption 6.79%, interferometer 13.41% and titration 21.78%. The repititions, which are necessary for the statistical safety of the methods, are given. By the method of infrared-absorption the higher water-loss of the soil is reduced by water-saturation of the air in the incubation vessel.
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Mean frequency estimators as used in pulsed Doppler ultrasound equipment should provide an accurate (quality) and consistent (robustness) estimate over a wide range of signal conditions. In a simplified signal model, the main parameters to consider are the noise level, mean frequency, bandwidth and power of both the Doppler signal and the stationary component over a given time window. It may be expected that one estimator for a given parameter combination exhibits a good performance while another estimator for the same parameter combination behaves poorly. To allow direct comparison between different types of frequency estimators, a method is introduced to evaluate the quality and robustness of estimators for a common signal space covering a wide range of realistic parameter combinations. The method is illustrated using three different mean frequency estimators: (1) a first order autoregressive estimator in combination with a stationary echo filter; (2) a second order autoregressive estimator; and (3) a complex linear regression estimator in combination with a stationary echo filter. It is concluded that, for the parameter combination considered, the complex linear regression estimator exhibits the best quality (low variance and bias of the estimate) and robustness (consistent quality for all parameter combinations).
A study was made to compare accuracy of the 24-hour recall, including both number of items recalled and amounts of food eaten, for elderly subjects using three methods: I, unaided oral recall, II, printed questionnaire, and III, interview with actual-size color pictures of foods. Sixty hospitalized patients, age 65 to 94, were interviewed. Factors studied for influence on scores were age, sex, educational level, obesity, place of residence, and food preparer. Results showed no significant difference in scores owing to method used, except that 30 subjects above the median age of 76 scored higher on number of items recalled and amounts of food eaten when using the printed questionnaire. None of the demographic factors studied made a significant difference in scores.
We investigated the suppressive effects of phosphate on calcium determinations with lanthanum-air/acetylene and potassium-nitrous oxide/acetylene methods, and we evaluated the ability of these methods to meet the suggested analytical goals for urine samples. The 20 g/L La-air/acetylene method was the most nearly accurate for predicting the actual calcium concentrations (t-test value = -0.042), followed by the 2 g/L K-nitrous oxide/acetylene method (t-test value = 0.450), 10 g/L La-air/acetylene (t-test value = -0.733), and finally 5 g/L La-air/acetylene (t-test value = -2.446). The dilution used significantly influences the apparent calcium concentration measured with the La-air/acetylene methods.
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Five different ultrasensitive thyrotropin (TSH) assay kits (Boots-Celltech, Immunotech, ORIS-CIS, Travenol and Boehringer) have been used for TSH measurements in various conditions. All the kits were based on an immunometric method but differed with regard to components and procedure. The sensitivity appeared essentially the same for the five kits (0.10 microU/ml) as well as the intraassay precision (coefficient of variation less than 12%). In contrast, the interassay coefficients of variation in the low TSH range varied from 12.8 to 21.3%. Discrepancies from kit to kit were observed and accounted for by differences in the components and procedure of the kits. Basal serum TSH was determined in normal subjects (n = 261) and in patients with thyroid dysfunction (n = 392). No overlap was shown between normals and patients with overt hypothyroidism. In contrast, an overlap existed between normals and hyperthyroids for all the kits but one. Measurements in patients with nontoxic goiter showed that TSH may be undetectable in clinically euthyroid patients, whatever the kit used. After TRH stimulation, 95% of the 375 patients tested associated either an absence of response to TRH with undetectable basal TSH values, or a blunted response with low basal TSH levels or normal response with normal basal TSH concentrations. However, 9 patients with suppressed TSH showed a response to TRH and 7 patients with normal basal TSH levels presented an exaggerated response to TRH. Taken together, these results demonstrate that even though ultrasensitive measurements of TSH do not meet the expectation of completely discriminating euthyroid from hyperthyroid patients, ultrasensitive TSH assay kits represent a powerful tool in the diagnosis of thyroid dysfunction, which would eliminate, in most instances, the need for TRH test and diminish thyroid hormone assay requests.
A comparative study of antimicrobial susceptibility patterns was performed for a five-year period in four hospitals affiliated with the University of Utah School of Medicine due to concern that susceptibility testing method and results differences between hospital units might complicate training and comprise initial antimicrobial therapy. Few significant pattern changes were detected within or between the individual hospitals during the five-year period, and variances between hospitals were in general no greater than variances demonstrated within individual service units within the University Hospital.