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At least 109 records · Page 6Linked to original sources
PubMed2004

Sonographic biometrical range of external genitalia differentiation in the first trimester of pregnancy: analysis of 2593 cases.

OBJECTIVES: The aim of this study was to establish the accuracy of fetal gender assignment by sonography in the biometrical range of 18 to 29 mm of biparietal diameter (BPD). METHODS: Transvaginal and/or transabdominal sonography was used to detect the sagittal sign as a marker of fetal gender in 2593 fetuses with BPD between 18 and 29 mm. The results of sonographic examination were compared with the gender at birth or with karyotype obtained from amniotic fluid cells or chorionic villus sampling. RESULTS: Fetal gender assignment was feasible in 2374 of 2593 cases (91%). Of the 2188 fetuses with known fetal sex outcome, 1025 were males and 1157 were females, and 6 had genital anomalies. In fetuses without genital anomalies, an accuracy rate of 100% was achieved at a BPD of >/=24 mm. The results of the six cases with genital malformations were considered separately. CONCLUSION: Sonography is a reliable method for the study of the morphological development of the external genitalia in fetuses 'in vivo'; it is possible to assign fetal gender in 95 to 99% starting at a BPD of 20 mm and to achieve an accuracy rate of 99 to 100% from a BPD of 22 mm, but fetal sex assignment should not be undertaken below a BPD of 22 mm, and especially not in cases where fetal sexing affects pregnancy management.

Amniotic Fluid↗
PubMed1994

Biometric assessment of prostate cancer's metastatic potential.

Currently, no protocol exists that can assess the metastatic potential of prostate adenocarcinoma. The reason for this is partly due to the lack of information on cellular changes that result in a tumor cell's becoming metastatic. In this investigation, attempts were made to devise a method that correlated with the metastatic potential of AT-1, Mat-Lu, and Mat-LyLu cell lines of the Dunning R-3327 rat prostatic adenocarcinoma system. To accomplish this, we applied BioQuant biometric parameters, i.e., area, shape factor, and cell motility. AT-1 had a lower shape factor and a greater area as compared with the more highly metastatic Mat-Lu subline. No significant difference in area or shape factor was detected between the AT-1 cell line and the highly metastatic Mat-LyLu line. However, the lowly metastatic AT-1 line had less motility as compared with the Mat-Lu and Mat-LyLu lines. This study revealed that metastatic potential could be partially predicted via area and shape factor and accurately predicted via cell motility.

Adenocarcinoma↗
PubMed1987

The posterior crico-arytenoid muscle in two cases of Shy-Drager syndrome with laryngeal stridor. Comparison of the histological, histochemical and biometric findings.

The histological, histochemical and biometric findings in the posterior crico-arytenoid muscle in two patients with Shy-Drager syndrome were compared with those found in cases of carcinoma of the larynx. In biopsy specimens from the patients with laryngeal carcinoma, neurogenic atrophy and various structural changes in the muscle fibres were the prominent features. In the two patients with Shy-Drager syndrome these changes were not present and the only significant finding was the more pronounced type I fibre atrophy, with type II fibre predominance in the more severely affected case. These findings do not permit the vocal cord paralysis seen in the Shy-Drager syndrome to be explained by motorneuron loss and denervation. It is postulated that a possible cause may be a biochemical defect in the brain.

Aged↗
PubMed1992

Biometrical analysis of individual growth curves.

Longitudinal data for height (length) between birth and 2 years of age were examined for 690 Dutch Registry twin pairs. A two-stage analysis was performed, where individual growth curves were first fit to available data for each subject using a linear multiple regression procedure and estimated individual growth curve parameters were then subjected to multivariate biometrical analysis. Quadratic polynomial curves were found to adequately represent observed growth patterns for the majority of cases (median R2 = .98). A specific scalar model of sex limitation best characterized individual variation in growth curve parameters. That is, there was significantly greater genetic variation for boys than for girls in both the predicted length and rate of growth at 1 year of age and the amount of deceleration in individual growth curves across age.

Anthropometry↗
PubMed1981

Genetics of escape-avoidance conditioning in laboratory and wild populations of rats: a biometrical approach.

The interest of biometrical geneticists in the genetic architecture of behavior is explained with reference to the additive, dominance, and epistatic components of variation and their relation to evolutionary pressures. For one phenotype, escape-avoidance conditioning in Rattus norvegicus, a fairly complete description of its genetic architecture has been gradually built and the major conclusions from four studies of this phenotype are reported: a selection study initially demonstrated the presence of large amounts of additive genetic variation and produced phenotypically extreme lines needed for later work; a diallel cross provided the opportunity for detailed examination of the dominance effects; a triple test cross permitted a similar examination of epistatic effects; and finally, another triple test cross using wild rats provided a confirmatory first attempt to test the assumption that a wild population's genetic architecture did not differ markedly from that found in laboratory populations. In relating the genetic findings to the evolutionary significance of behaviors in the escape-avoidance paradigm, it is argued that interspecific comparisons might play a major role.

Animals↗
PubMed1984

Circatrigintan (30 +/- 5 d) variations of the cellular component of female urethral expulsion fluid. A biometrical study.

Data on the amount of uroepithelial squamous cells released into the fluid of urethral expulsions were obtained in a 37-year-old multipara by daily five consecutive repeated applications of the digital stimulation technique, carried out over the period of one and a half of her menstrual cycle. During the secretory phase of the cycle the rate of the cellular component was far higher than during the proliferative phase. These quantitative biometrically analysed data provide a complementary picture to the qualitative cytological changes of uroepithelial squamous cells occurring during the menstrual cycle that have been reported so far.

Adult↗
PubMed1986

Preliminary note on biometric data relating to the human coraco-acromial arch.

A biometric study based on 20 human scapulae made it possible to specify the variations in the gap of the coraco-acromial arch in relation to its depth and height. A graphic representation in rectangular coordinates, then in spatial representation in relation to the three planes of reference, leads to the following findings: the bony variations in the arch occur essentially: at the coracoid apophysis, and two types of arch can be distinguished depending on the predominance of bony or of ligamentous components.

Acromion↗
PubMed1994

The biometric evaluation of the acute-toxic-class method (oral).

The acute toxic class method (ATC method) is an alternative to the LD50 test, with the use of substantially fewer animals needed for the classification of substances. Like the classical LD50 test the biometry of the ATC method is based on the probit model. The biometric calculations of the ATC method were carried out not only for the classification categories of the European Union but also for the classification criteria of various countries and organizations, currently in use. It is demonstrated that in comparison with the LD50 test in general the same classification is obtained with the ATC method and with the use of substantially fewer animals. Substances with high slopes are likely to be allocated to the predicted toxicity class in comparison with substances having low slopes, with both the ATC method and the LD50 test. Substances are more likely to be allocated into a lower toxicity class with the LD50 test than with the ATC method.

Animal Testing Alternatives↗
PubMed2001

Extracorporeal shockwave therapy (ESWT) in the treatment of plantar fasciitis--a biometrical review.

The application of extracorporeal shockwave therapy (ESWT) as a treatment for conservatively unsuccessfully treated plantar fasciitis has experienced a rapid increase over the last years. However, the efficacy of ESWT has not yet been established unequivocally, as published studies have led to inconsistent results. Furthermore, reviews on clinical trials on ESWT are either not up to date, incomplete, or methodologically inadequate. As a consequence, a systematic literature search was conducted which yielded 21 relevant articles on ESWT in the treatment of plantar fasciitis. These were rated according to biometrical criteria for the conduct of therapeutic trials based on international guidelines. None of the rated trials fulfilled all of the criteria, and it is concluded that at this point the efficacy of ESWT can be neither confirmed nor excluded. Randomised and controlled clinical trials are required to adequately estimate the value of ESWT as a treatment for plantar fasciitis.

Biometry↗
PubMed2001

[Biometric data on risk of pneumothorax from vertical infraclavicular brachial plexus block. A magnetic resonance imaging study].

In the present study 48 sagittal and transversal magnetic resonance images of volunteers were examined for biometric data concerning risk of pneumothorax at the vertical infraclavicular blockade (VIP) of the brachial plexus. With a correct puncture the plexus can be reached after 3 cm. The shortest way to the lung is 5.3 cm (3.1-8.7 cm) at a incorrect medial angle of puncture of 46.3 degrees (35-58 degrees). While moving the angle of puncture at a minimum of 24.1 degrees (1-51 degrees) in a medial direction, a depth of 6.1 cm (4-8.9 cm) has to be reached for fatal lung puncture. The puncture point has to be determined 2.8 cm (0-4.1 cm) towards the midline of the body to have a pleura connection by a strictly vertical puncture at 6 cm (4-8.9 cm). In asthenic women, shorter distances were obtained. A considerable lower deviation can lead to pleural damage (7.5 degrees; 4.7 cm). The plexus is very close to the skin surface (1.6-3 cm). In one case, the risk for pneumothorax could be measured even with the correct puncture technique. Overall, the VIP is a very safe method for brachial plexus anaesthesia with regard to the risk of pneumothorax. In asthenic women, the risk seems to be higher but can be minimised by reducing the maximum puncture depth.

Brachial Plexus↗
PubMed1997

The inhalation acute toxic class method: test procedures and biometric evaluations.

A method of inhalation acute toxic (ATC) classification is presented with the use of significantly fewer animals in comparison with the classical LC50 test. The principle of the inhalation ATC method is based on the oral ATC method, which has been adopted in 1996 as an official test guideline of the OECD and the European Union. The inhalation ATC method, like the oral ATC method, is a stepwise procedure; three animals of each sex are used simultaneously for each tested concentration, and not, as in the oral ATC method, three animals of each sex separately for each dose. The method was developed for three starting concentrations and two reference systems (based on ppm and mg/l). Depending on the LC50, slope, classification system and starting concentration, on average 50 to 80% fewer animals will be used in comparison to at least 30 animals with the classical LC50 test. The method was biometrically evaluated with the use of the probit model for dose-response relationships. At present, there are 12 different international classification systems based on LC50 values: 6 systems referring to mg/litre and 6 systems based on ppm values, and exposure time varying from 1 to 4 h. The test procedures and the calculations of the classification probabilities demonstrate that the inhalation ATC method is a reliable alternative to the classical LC50 test with the use of significantly fewer animals. Classification probabilities are presented for all classification systems currently in use, and expected numbers of experimental and of moribund/dead animals are demonstrated for one system of each reference system and for all three starting concentrations. The conclusion is justified that there is no need to validate the inhalation ATC method with the use of experimental animals.

Administration, Inhalation↗
PubMed1998

The dermal acute toxic class method: test procedures and biometric evaluations.

A dermal acute toxic class (ATC) method is presented with the use of significantly fewer animals in comparison with the classical dermal 50% lethal dose (LD50) test. The principle of the dermal ATC method is based on the oral and the inhalation ATC method. The method was developed for three fixed starting doses. Depending on the dermal LD50, the slope, the classification system and the starting dose on average 40 to 90% fewer animals will be used in comparison to at least 30 animals with the dermal LD50 test. The method was biometrically evaluated by using the Probit model for dose-response relationships. At present, there are eight different international classification systems based on dermal LD50 values. The test procedures and the calculations of the classification probabilities demonstrate that the dermal ATC method is a reliable alternative to the dermal LD50 test with the use of significantly fewer animals. Classification probabilities are presented for all classification systems currently in use, and expected numbers of experimental and of moribund/dead animals are demonstrated for the system of chemicals in the European Union for all three starting doses. The conclusion is justified that, similarly to the inhalation ATC method, there is no need to validate the dermal ATC method with the use of experimental animals.

Animals↗
PubMed1998

Morphologic, biometric, and isoenzyme characterization of Trichuris suis.

Trichuris suis isolates were collected from the cecum of Sus scrofa domestica (pig) and S. s. scrofa (wild boar). Morphology and biometry studies were carried out. Morphology studies showed the existence of typical caudal papillae in males of T. suis from wild boars, but no other difference was observed in the biometric parameters (total length, esophageal length, posterior-portion body length, and spicular length) of T. suis isolated from either host. Individual extracts were subjected to malate dehydrogenase (MDH), malic enzyme (ME), glucose 6-phosphate dehydrogenase (G6PD), lactate dehydrogenase (LDH), and superoxide dismutase (SOD) isoenzyme analysis following starch-gel electrophoresis, and the isoenzyme patterns were compared with those obtained from other species of trichurids. MDH, ME, G6PD, LDH, and SOD isoenzyme patterns were identical for T. suis from both hosts. MDH isoenzyme patterns were characterized by the presence of one cathodic isoenzyme. ME, G6PD, and LDH isoenzyme patterns indicated the presence of three phenotypes, whereas the SOD isoenzyme pattern showed only one phenotype characterized by the existence of two (anodic and cathodic) bands. Different LDH and SOD isoenzyme patterns observed for T. suis, T. ovis, and T. skrjabini confirm once more that isoenzyme patterns have potential as a diagnostic tool for differentiation of different species of Trichuris.

Animals↗
PubMed2006

The influence of the biometric parameters on metallothionein and metal level in the heat-treated cytosol of the whole soft tissue of transplanted mussels.

The influence of the biometric parameters (shell mass, whole soft tissue mass, condition index) on MT and metal levels in the heat-treated cytosol of the whole soft tissue of transplanted mussels was studied over the period of one year. The positive correlation of three metals (Cd, Fe, Zn) with the shell mass indicated to time-dependent increase of their contents. Strong correlation of Mn content with the whole soft tissue mass (r = 0.74, p < 0.0001), and almost identical changes of these two parameters over the year make Mn a good indicator of mussel's condition. As opposed to the other metals, Cu content does not exhibit connection with biometry. On the other hand, MTs are highly influenced by biometry. As much as 65% of their variability could be explained by the changes of the shell mass and the whole soft tissue mass. Consequently, it is difficult to distinguish if the obtained positive correlation between Cd and MTs (r = 0.48, p < 0.05) reflects MT induction by Cd, or Cd accumulation as a result of age-dependent increase of MTs. Due to the strong influence of the biometry on MT level, the whole soft tissue is not considered as the best choice for measuring MTs as a biomarker. Better option would be to isolate a specific tissue that shows indisputable connection between MT induction and metal accumulation.

Animals↗
PubMed1993

A biometric analysis in the rat of the horizontal component of physiological tooth migration and its response to altered occlusal function.

The direction and amplitude of physiological tooth migration, as well as the influence of occlusal force on this movement, were evaluated macroscopically in the rat by biometric means. The first experiment, which compared the position of the teeth in the anteroposterior plane of the maxilla between two groups of 20 and 28 rats killed at age 15 and 52 weeks, respectively, confirmed the distal direction of this drift. In a second experiment, after suppression of the antagonist occlusal contacts of the maxillary left dental hemiarch in nine rats, the migration of this hemiarch was compared to that of the hyperfunctional contralateral hemiarch and to that of the molars in a control group of 20 rats. A statistically significant (t-test) reduction of the physiological migration in the absence of occlusion, was revealed.

Animals↗
PubMed1985

Biometric comparison of bur and electrosurgical retraction methods.

A biometric comparison of two retraction methods was made on 20 adult patients who received complete crowns. Free gingival tissue height was recorded after 4, 8, and 12 weeks. The conclusions were (1) the electrosurgical method showed more tissue loss at each time interval than the bur method, (2) electrosurgical retraction showed more subject variability than the bur method, (3) clinically, the tissue appearance of both groups was indiscernable at the time intervals tested, and (4) the electrosurgical method provided for a greater bulk of impression material at the margin than the bur method.

Adult↗
PubMed1981

A biometrical-genetic analysis of granule cell number in the area dentata of house mice.

Considerable variability in the number of granule cells in the area dentata has been found among inbred strains of mice. In this report a simplified triple-test cross breeding design was employed to identify and discriminate between heritable and non-heritable sources of this variability. Granule cell numbers were estimated in two previously identified extreme strains of mice and in their reciprocal F1 hybrids with 3 strains of mice known to be intermediate between the 2 extremes. Analytical techniques of biometrical genetics applied to the neuron number estimates indicated that genetic transmission of this trait involves genes located upon autosomes. Transmission does not involve cytoplasmic factors within the female egg, or maternally-mediated differences in nutrition. Of the total variability in dentate granule cell number, 86% is estimated to be determined by an additive genetic component. A dorsal-to-ventral increase in the size of granule cell nuclei was found for all genotypes; some possible bases for this increase are discussed.

Animals↗
PubMed1985

Biometrical studies upon hominoid teeth: the coefficient of variation, sexual dimorphism and questions of phylogenetic relationship.

Sexual dimorphism as a function of variation in hominoid tooth metrics has been investigated for four groups of taxa: Recent great apes (two subfamilies), Dryopiths (one subfamily), Ramapiths (one subfamily) and hominids (one family). Gorilla, and to a lesser extent Pan, appear characterized by very high levels of sexual dimorphism and meet several criteria for statistical outliers. Recent great apes are the only group exhibiting consistently high levels of sexual dimorphism. Ramapiths are the only group characterized by low levels of sexual dimorphism and their relative canine length is most similar to Dryopiths. Both Dryopiths and hominids contain taxa with low and intermediate levels of sexual dimorphism. The Gingerich and Shoeninger hypothesis relating coefficients of variation to occlusal complexity is supported. Non-parametric statistics suggest that homogeneity of coefficient of variation profiles over most of the tooth row is characteristic of only the Dryopiths and a composite data set composed of the Dryopith plus Ramapith tooth measurements. Oxnard's model for the multifactorial basis of multiple sexual dimorphisms is also supported. The Dryopith and hominid patterns of sexual dimorphism are similar, an observation that suggests phylogenetic relationship. At the taxonomic level of subfamily or family, sexual dimorphism is a character of cladistic usefulness and possible phylogenetic valence. Assuming that breeding system and sexual dimorphism are functional correlates as many workers suggest, then Ramapithecus sp. China, Sivapithecus indicus and possibly Australopithecus boisei are good candidates for having possessed monogamous breeding/social structures. All Dryopith taxa, S. sivalensis, Sivapithecus sp. China, A. afarensis, Homo habilis and H. erectus emerge as the best candidates for having possessed a polygynous breeding/social structure. No biometrical affinities of Ramapiths with hominids can be demonstrated and some phylogenetic relationship with Dryopiths is suggested. Kay's interpretation of Ramapith sexual dimorphism and taxonomic affinity is not supported. The lack of control over temporal and geographic range variation is discussed and the loose association of these variables with differences in tooth morphology is noted. The high heritability of tooth size also suggests that assignment of "high" or "low" index values to extinct taxa as a measure that describes evolving clades at discrete points in evolutionary time is appropriate.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗