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1.
Cephalometry, X-ray cephalometry, and somatoscopy were used in the studies of 65 adult males with a severe unilateral microtia subdivided into three groups: with marked asymmetry, with slight asymmetry, and without any obvious facial asymmetry. The group with marked asymmetries was designated as hemifacial microsomia. In this group the affected side of the face was depressed on the average from above and from below towards the level of the external auditory canal. The center of the anteroposterior reduction was situated in the region in front of the pterygomaxillar fissure. The anteroposterior and vertical facial dimensions on the affected side were reduced most markedly, while the width dimensions showed the slightest changes. Hypoplasia was most severe within the lower face and increased towards the otocephalic centre. The mandibular joint was displaced in an anteroinferior and medial direction. Hypertelorism did not occur, but the orbit on the affected side was smaller in height and was frequently vertically dislocated. The facial profile was unchanged except for retrusion of the chin and increased frequency of bite disorders. The mobility of the mandible was limited. Hemihypoplasia also exerted an influence on structures that were not of branchiogenic origin, e.g., the cranial base (narrowing, asymmetry, and more pronounced curvature), the neurocranium (depression in mastoid and tympanotemporal regions, posterior rotation of the vault), and the frontonasal component (deviation of the nose and premaxilla). The cranial vault and the bottom of the occipital bone showed on the average no asymmetries. The similar character of deviations in slightly affected groups revealed that in spite of the high variability of changes typical for branchiogenic malformations the development of the face in these defects was subjected to certain rules. Marked facial asymmetry occurred only in every fifth patient with a severe degree of microtia, while definite signs of asymmetry were absent in every third patient.  相似文献   

2.
Congenital muscular torticollis is caused by idiopathic fibrosis of the sternocleidomastoid muscle that restricts movement and pulls the head toward the involved side. Deformation of the craniofacial skeleton will develop if the restriction is not released and result in aesthetic and functional problems. The purpose of this study was to use three-dimensional computed tomography imaging for qualitative and quantitative evaluation of the craniofacial deformity in a series of patients with uncorrected congenital muscular torticollis, and to assess age as a precipitating factor for severity of the deformity. A total of 14 patients from 1 month to 24 years of age were included. The skull images were rotated into standard orientation and reconfigured for evaluation of the cranium, endocranial base, and facial skeletal structures. The midlines of cranial base and facial bone, angle of midline deviation, width of each hemicranium and hemiface, and the orbital index were defined and measured. The results showed that the cranium and cranial base deformation took place as early as in infant stage, with the most prominent change occurring in the posterior cranial fossa. Facial bone asymmetry started to appear after 5 years of age, at which time the mandibular and occlusal abnormalities were observed. The deformity of the orbits and maxilla occurred at an older age, characterized by the deviation and decreased vertical height on the affected side. The severity of the observed deformities increased with age. The angle of midline deviation was 2.48 +/- 1.68 degrees in the cranial base and 3.26 +/- 3.28 degrees on the facial bone. Both of the midline deviations were significantly correlated with age. Compared with the contralateral side, the width of the ipsilateral posterior hemicranium was longer (54.36 +/- 6.72 mm versus 50.81 +/- 6.55 mm), and the width of the ipsilateral lower hemiface was shorter (35.30 +/- 7.27 mm versus 43.49 +/- 11.34 mm). Both differences were statistically significant. Measurement of the orbital index demonstrated a significantly flatter orbit on the ipsilateral side (89.48 +/- 0.11 versus 92.74 +/- 0.08). This study showed that the cranium and cranial base deformity occurred early in patients with uncorrected torticollis, while the facial bone deformity occurred in childhood stage. The cranial and facial deformity became more severe with age. Early release of the muscle restriction is advised to prevent craniofacial deformation.  相似文献   

3.
The shape of the craniofacial complex was analysed cephalometrically in sixty-four adult 45,X females (Turner syndrome) using lateral skull radiographs, and the subjects were compared with first-degree female relatives and control females. The results showed that 45,X females have marked changes in relatively few craniofacial areas compared to the controls. Most of the changes are located in the cranial base, so that the face is retrognathic. The mandible is short, whereas the maxilla is of normal length. The results support the view that the morphology of the cranial base is markedly affected in 45,X females, whereas most other craniofacial changes could be considered secondary to the cranial base abnormality. It is suggested that retarded cartilage growth may be a factor leading to the present findings.  相似文献   

4.
The regions of deviation method has been proposed as a technique for identifying regions of the gait cycle where joint motion deviates from normal (Shorter et al., 2008). The original statistical analysis distinguished only peak values during stance and swing. In the current article, we extend the approach by examining deviations from normal throughout the entire gait cycle using pointwise t tests. These methods were demonstrated on hind-limb joint angles of 21 Labrador Retrievers without and with cranial cruciate ligament disease. Results were compared with peak difference analysis previously performed on these subjects. All points in the gait cycle where symmetry deviations were significantly affected by cranial cruciate ligament disease (via pointwise t tests) were defined as regions of deviation from symmetry. Discriminant function analysis was used to consider single subjects and validate that these regions were truly areas of difference between groups. Regions of deviation encompassed previously determined significant peak differences, while extending analysis to additional areas of asymmetry. Discriminant function analysis suggested that the region of deviation method is a viable approach for distinguishing motion pattern differences. This enhanced method may help researchers better understand the mechanisms behind lameness and compensation.  相似文献   

5.
Nutritional imbalance is one of the main sources of stress in both extant and extinct human populations. Restricted availability of nutrients is thought to disrupt the buffering mechanisms that contribute to developmental stability and canalization, resulting in increased levels of fluctuating asymmetry (FA) and phenotypic variance among individuals. However, the literature is contradictory in this regard. This study assesses the effect of prenatal nutritional stress on FA and among‐individual variance in cranial shape and size using a mouse model of maternal protein restriction. Two sets of landmark coordinates were digitized in three dimensions from skulls of control and protein restricted specimens at E17.5 and E18.5. We found that, by the end of gestation, maternal protein restriction resulted in a significant reduction of skull size. Fluctuating asymmetry in size and shape exceeded the amount of measurement error in all groups, but no significant differences in the magnitude of FA were found between treatments. Conversely, the pattern of shape asymmetry was affected by the environmental perturbation since the angles between the first eigenvectors extracted from the covariance matrix of shape asymmetric component of protein restricted and control groups were not significantly different from the expected for random vectors. In addition, among‐individual variance in cranial shape was significantly higher in the protein restricted than the control group at E18.5. Overall, the results obtained from a controlled experiment do not support the view of fluctuating asymmetry of cranial structures as a reliable index for inferring nutritional stress in human populations. Am J Phys Anthropol 154:544–553, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

6.
A study of 491 patients with femur-fibula-ulna (FFU) complex is presented. The term FFU complex has been proposed for cases in which the femur, fibula and/or ulna show defects, which tend to be associated. These cases are usually sporadic. Some rare anomalies of the arms which are present are particularly frequent in FFU complex. These are amelia, peromelia of humerus, humeroradial synostosis and defect of ulna. In our study, 491 patients were investigated for involvement of limb malformations. Our results, showing nearly equal proportions of the most common malformations in four analysed groups (with one, two, three and four limbs affected) supports the hypothesis that even if one arm or one leg only is affected, the cases may still be classifiable as FFU complex. There is a striking asymmetry in presence and in degree. All malformations are more often unilateral than bilateral. Upper limbs are affected more often than lower limbs. The right side and the male sex are preferentially affected. The limb malformations present in the FFU complex are different from those seen in most other types of limb defects, so there is virtually no overlap between FFU and other limb malformations. Some arguments in favour of early somatic mutation as a cause are discussed.  相似文献   

7.
Previous studies of population structure among prehistoric groups in the Ohio valley region have shown that hunting-gathering populations exhibited a different structure than horticultural populations. Among both Late Archaic hunter-gatherers and Late Prehistoric horticulturists, covariance structures for cranial metrics were found to be homogenous within the populations, but the Late Archaic subpopulations showed little differentiation while the Late Prehistoric subpopulations exhibited a marked differentiation. Biodistance based on cranial discrete trait frequency showed similar patterns, but in the Late Archaic discrete trait distance was associated significantly with the geographical distance separating populations. The present investigation is an extension of the previous studies increasing the Late Prehistoric sample (n = 8 samples and n = 341 individuals) and using the Harpending-Ward model, modified for use with multivariate quantitative data, to estimate the effects of differential gene flow and the amount of differentiation within populations. Results of the present analyses indicate that differentiation among subpopulations, measured by minimum F(ST), was greater in the Late Prehistoric compared to the Late Archaic period. However, for both periods the minimum F(ST) is comparable to values found for historic native populations of the northeast woodlands. Analysis of differential gene flow in the Late Archaic period indicates that geographically peripheral populations were affected more by external gene flow than more central populations. Late Prehistoric populations exhibit a very complex pattern of differential gene flow. We discuss the latter pattern in terms of proposed culture change in the Late Prehistoric period of Ohio.  相似文献   

8.
Atelencephalic microcephaly, a rare and extreme disorder, is known morphologically by only six cases. Derivatives of the telencephalon are absent or dysplastic, while more caudal structures are normal or mildly deformed. A more extensive form, aprosencephaly, involves structures of the diencephalon and may be associated with holoprosencephalic facies. Extracranial anomalies may be present in both atelencephaly and aprosencephaly. We describe the seventh and youngest specimen, a 21-week female with atelencephaly. Maternal and gestational histories were unremarkable; the fetus was obtained by therapeutic abortion following diagnosis of a severe cranial malformation by ultrasound. A small and depressed, but intact, calvarium covered the brain. The forebrain was rounded and showed fused hemispheres, absent gyri, olfactory bulbs, and tracts. Caudal structures were mildly deformed. An oval mass of bone filled much of the middle cranial fossa. By light microscopy, several dysplastic changes were apparent in the forebrain. Ventricles were not present; small round cells resembling those of the germinal matrix were prominent in the forebrain. Pyramidal tracts were absent at all levels. The process responsible for these changes cannot be established with certainty; the changes are, however, in keeping with previous damage, such as that accepted for other encephaloclastic disorders. The insult in atelencephaly presumably occurs after closure of the rostral neuropore; earlier damage, with more widespread consequences, is possible for aprosencephaly. As with other destructive processes, etiology in atelencephaly and aprosencephaly is most likely heterogeneous.  相似文献   

9.
Crocodilians show a high degree of cranial variation and convergence throughout their 80 million-year fossil record that complicates their phylogenetic reconstruction. Conflicting phylogenetic results from different data partitions and character homoplasies typify crocodilian phylogeny, and differences between molecular and morphological phylogenetic hypotheses are believed to be associated with the slender-snout skull shape of Gavialis gangeticus and Tomistoma schlegelii. Slender-snout skulls are one of five identified eusuchian cranial ecomorph shape categories (ESCs) thought to reflect functional or ecological specialization. This paper tested the effect of transitions among general, blunt and slender ESCs on cranial character-state distributions in phylogeny using the concentrated changes test. In addition, 'tree-free' character compatibility analysis of character independence was conducted on the morphological character matrix to determine if character correlations are observed independent of specific tree topologies. Results suggest cranial ESCs do affect cranial character-state gains in phylogeny. Concentrated changes identify a broad suite of character-state changes that significantly correlate with transitions to slender, general and blunt ESCs on morphological, molecular and combined-data tree topologies, but numbers of correlated characters for each category differ according to topology. Character compatibility analysis results do not mirror the concentrated changes test results and reflect hierarchically distributed support throughout the data. As cranial ESCs affect character-state transitions, it is possible that nonphylogenetic variables could affect inferences of crocodilian phylogeny by affecting cranial morphology.  相似文献   

10.
Ultrasonography is a powerful new tool in reproductive physiology and ecology but quantitative evaluations of acoustic window efficacies are necessary to assess methodological accuracy. We evaluated the efficacy of the left inguinal, right inguinal and cranial acoustic windows for detecting ovarian follicles and oviducal eggs in three tortoise species. Incorporating cranial results improved upon inguinal efficacies for detecting follicles in the three species, and for detecting eggs in Chersina angulata, which had small inguinal apertures for its body size. The cranial window provided the best follicle results (highest numbers detected) but the left inguinal window provided the best egg results. This asymmetry was probably due to the primarily posterior position of the oviducts (eggs) and the pliable ovarian sheets allowing follicles to move cranially. The left-right asymmetry may result from intestinal asymmetry (i.e., between the cecum and descending colon) in obscuring ultrasound transmission or displacing follicles and eggs. Seasonal influences upon efficacies varied with species, partially due to species differences in a) reproductive cycles and b) size and number of follicles and eggs. We attributed other efficacy differences among species to differences in body size and shell morphology, especially the inguinal apertures. Correlation analyses revealed strong individual influences upon window efficacy, suggesting that individuals varied in the position of follicles and eggs and the degree of obfuscation by nonreproductive structures. The paucity of correlations between efficacies and body size reflects the complex interactions of body size, shell morphology, reproductive structures and reproductive cycles on efficacies.  相似文献   

11.
A new type of cardiac malformation in rainbow trout Oncorhynchus mykiss from a broodstock fish farm is described. The ventricle of affected fish was located dorsodextrally to the atrium, while the latter was saccular, grossly enlarged and protruded through the muscles of the ventral body wall, forming a hernia covered only by dermis and epidermis. Histopathological changes included hypoplasia of the outer compact layer of the ventricular myocardium and severe distension of trabecular structures within the ventricle and atrium. Affected fish tolerated stress very poorly, and the majority of the affected fish died during the freshwater period. The causation(s) are not known, but hereditary and environmental factors are likely, as no infectious agents were isolated or detected microscopically.  相似文献   

12.
On 14 March 2001, an 8 mo old, male white-tailed deer (Odocoileus virginianus) was found in lateral recumbency exhibiting neurologic signs including inability to rise, opisthotonus, paddling, and respiratory distress. There was evidence of minor cranial trauma. Postmortem examination revealed atlantoaxial instability with ventral deviation of the axis due to malformation of the caudal atlas and cranial axis. Given the age of the fawn, the instability was assumed to be congenital with minor trauma inducing severe, acute neurologic signs.  相似文献   

13.
We tested whether directional selection on an index-based wing character in Drosophila melanogaster affected developmental stability and patterns of directional asymmetry. We selected for both an increase (up selection) and a decrease (down selection) of the index value on the left wing and compared patterns of fluctuating and directional asymmetry in the selection index and other wing traits across selection lines. Changes in fluctuating asymmetry across selection lines were predominantly small, but we observed a tendency for fluctuating asymmetry to decrease in the up-selected lines in both replicates. Because changes in fluctuating asymmetry depended on the direction of selection, and were not related to changes in trait size, these results fail to support existing hypotheses linking directional selection and developmental stability. Selection also produced a pattern of directional asymmetry that was similar in all selected lines whatever the direction of selection. This result may be interpreted as a release of genetic variance in directional asymmetry under selection.  相似文献   

14.
The method of multiple correlations was used to assess the interrelations between basic characteristics of the facial bony framework and the cranial base. The study was based on x-ray measurements in 50 normal adult males, and the result disclosed the extent to which the variability of the investigated characteristics was determined by the variability of several combined facial parameters. The characteristics of shape and position of individual facial structures were more closely interrelated than characteristics of size. The lowest degree of association was shown by the parameters of the cranial base, which confirmed its independent development. The highest degree of interrelations was shown by the parameters of shape and position of the lower jaw, which characterized the marked adaptation and compensation capacity of the mandible. Some of these relations were causal. The present findings could be useful in orthodontic therapy and during anthropologic reconstructions.  相似文献   

15.
The present paper considers the significance of interosseous flexions of the palatal complex in the process of orthocephalization of the rat skull between birth and 7 d p.n. The study is based on a sample of 90 rats divided into 4 age groups, i.e. 0, 4, 7, and 14 d. These rats have been X-rayed, and their photographs subsequently analysed. During the studied period, the constituents of the bony palate, i.e. the horizontal part of the palatine bone, the palatal process of maxilla and the palatal part of premaxilla, increase markedly in length, but with individual differences in growth rate. There is, in the period, a marked decrease in angulation between the cranial base and the palatal plane. This means that the rat skull becomes more orthocranial. There is also a straightening (orthopalatalization) of the palate, as the angle between maxilla and premaxilla becomes more obtuse, and a marked decrease in angulation between the palatine bone and the cranial base. The patterns of angular changes suggest that the process of orthocephalization in the period between birth and 14 d p.n. primarily is a result of an upwards rotation of the palatine bone relative to the cranial base, while interosseous deflections in the palate only play a minor role.  相似文献   

16.
This article generalizes the results of many years’ studies of the EEG of patients with tumorous lesions in the diencephalic, brainstem, and limbic structures, which fulfill the regulatory function in ensuring integral brain activity. The specific features of the inclusion of individual structures under investigation in the organization of the intra- and interhemispheric relations of cortical biopotentials were demonstrated against the background of diffuse changes in the biopotentials that reflect the systemic character of neurodynamic reorganizations when the regulatory brain structures are involved in the pathological process. This study expands the idea of the predominant functional connection of the diencephalic structures with the right hemisphere and brainstem structures with the left one with determination of the regional specific features of changes in the intrahemispheric EEG coherences. The distinguishing features of intercentral relations when the limbic structures are involved in the pathological process show similarity with the neurodynamic reorganizations in patients with lesions in both diencephalic and (even more so) brainstem structures. Universal elements were detected in the formation of integral adaptive reactions of the brain with lesions in its regulatory structures, which reflects their close functional interaction and makes it possible to consider them the individual links of an integral regulatory system. The study revealed reciprocal changes in various forms of electrical activity, which reflects reciprocation of interaction of individual regulatory structures. This is one of the EEG equivalents of the formation of adaptive-compensatory cerebral reactions. The specificity of influence of the studied regulatory structures are clearly seen in situations of their morphofunctional isolation observed during cerebral coma. In these conditions, when the cortex is functionally inactive, the authors demonstrated the dynamic character of changes in interhemispheric asymmetry, which reflects the dominance of individual links of the regulatory system playing the role of supreme regulator of life support of the body in critical states.  相似文献   

17.
零模型是判定网络嵌套性的重要依据, 菌根共生关系网络经常出现高度非对称性, 该文通过探究矩阵非对称变化对基于不同零模型构建方法的网络嵌套性的影响, 试图为非对称网络零模型的选择提供依据。结果表明: 不同零模型保守性不同, 增加限定条件减少零模型构建过程中的自由空间, 高度限定条件易导致第II类错误。高度非对称网络会增加基于完全随机(r00)零模型的矩阵温度(NT)偏离、降低配对重叠度(NODF)偏离, 标准化指数z-score值显示网络非对称增加后有助于NTNODF显著性判定。行或列限定对非对称网络嵌套性判定的影响存在差异, 列限定(c0)的网络嵌套性判定对网络非对称性变化的响应规律与r00零模型的响应趋势基本一致, 具有更低的嵌套性偏离和标准差值。行限定(r0, 包括行列限定(backtrack))零模型NT值和NT偏移随矩阵非对称性的变化保持稳定, 较之c0零模型在高度非对称网络中呈现更低的NODF偏离值。选用完全随机和限定零模型相结合的方法, 有助于更加准确判断非对称网络是否具有嵌套结构。高度非对称网络嵌套性判定中对行属性特征比较敏感, 不同非对称性网络间嵌套性水平相比较时选用r0零模型要优于r00和c0零模型。  相似文献   

18.
Seven different limb malformations types were defined in 544 affected newborns, apparently free from other anomalies, obtained from a series of 297,299 livebirths. These seven malformation types were: polydactyly, limb reduction, brachydactyly, symphalangy, syndactyly and split hand/foot. One anomaly type was present in 472 newborns (1.58/1,000) and two or three in 72 (0.24/1,000). The observed combinations of two or three limb malformation types cannot be explained as chance association. Therefore, a common etiopathogenic mechanism has to be considered when two or more limb malformation types are combined in a given individual. The most frequent observed combinations were: reduction-brachydactyly, reduction-syndactyly, brachydactyly-syndactyly, polydactyly-syndactyly, and reduction-brachydactyly-syndactyly. Based on affected limb distribution, sex ratio, and familial recurrence rates, it is suggest that a reduction anomaly is the primary component in all tested combinations while syndactyly tends to be a secondary one when combined with any other limb anomaly type.  相似文献   

19.
Present paper presents proton MRS investigation results. The investigation was carried out with Magnetom Vision device. Twenty-five patients in the age of 20-44 years suffering with generalization epileptic fits validated by EEG (no visible changes on MRT) were examined. In all cases independently on the localization of the changes, decreasing of NAA and increasing of Cho were recorded. At one side temporal lobe injury recorded by EEG at the damaged part decreasing of NAA/Cr and NAA/Cho + Cr ratios were registered. Patients with bilateral changes registered by EEG showed non-equal changes of metabolite concentration on both sides. Examination of patients suffering with distinct symptoms of temple epileptics has shown ipsilaterality decrease of NAA and Cr concentration. But on the injured side NAA/Cr ratio decrease was more distinct. In general, the laterality was recorded in 14 patients out of 22 with pathological changes registered by proton MRS and in 10 patients out of 14 the above mentioned changes corresponds to the side of the fit initiation. In the patients with bilaterality changes NAA/Cr ratio asymmetry was recorded in all cases, but the most distinctly in the medium part of the temple lobe. Comparison of data recorded in 8 patients suffering with one side fit complex has shown significant asymmetry of metabolites which was observed in ipsilaterality and contra laterality NAA ratio obtained in hippocampal areas. Difference in NAA ratio obtained between left and right sides are 19-25%. Left-right ratio of other metabolites corresponded to that ratio in the control group and was symmetrical.  相似文献   

20.
P2X receptors are non-selective cation channels operated by extracellular ATP. Currently, little is known concerning the functions of these receptors during development. Previous work from our lab has shown that zebrafish have two paralogs of the mammalian P2X3 receptor subunit. One paralog, p2rx3.1, is expressed in subpopulations of neural and ectodermal cells in the embryonic head. To investigate the role of this subunit in early cranial development, we utilized morpholino oligonucleotides to disrupt its translation. Loss of this subunit resulted in craniofacial defects that included malformation of the pharyngeal skeleton. During formation of these structures, there was a marked increase in cell death within the branchial arches. In addition, the epibranchial (facial, glossopharyngeal, and vagal) cranial sensory ganglia and their circuits were perturbed. These data suggest that p2rx3.1 function in ectodermal cells is involved in purinergic signaling essential for proper craniofacial development and sensory circuit formation in the embryonic and larval zebrafish.  相似文献   

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