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1.
Visually seriated radiographs of the proximal femur, proximal humerus, clavicle, and calcaneus from 130 individuals from the Hamann-Todd collection were examined as indicators of skeletal age at death. The clavicle demonstrated the most consistent relationship to age in both sexes. The same radiographs were also seriated by size-normalized optical density as a means of establishing relative radiolucency. In this context, visual seriation proved superior. The four sites studied showed strong divergence in response to age. Since each was sampling bone response from the same individual, it is concluded that bone loss is highly site specific. This demonstrates the individual character of specific skeletal sites. Visual inspection of clavicular radiographs, seriated on a populational basis, provides age estimates that are comparable to anatomical age indicators and provides independent estimates of skeletal age when included in the summary age method (1985: Am. J. Phys. Anthropol. 68:1–14).  相似文献   

2.
LeClair EE 《Tissue & cell》1995,27(5):539-543
Local areas of roughened skeletal calcite are reported from the otherwise smooth, imperforate skeletal articulations of the ophiuroid vertebral ossicle (Echinodermata: Ophiuroidea). Complementary patterns of roughness on both proximal and distal articulating surfaces suggest local points of wear between adjacent ossicles, presumably caused by repeated rotation of the intervertebral joint. This surface feature is discussed with respect to its possible origin (mechanical action, resorption of skeletal material, experimental artifact) and the functional morphology of the ophiuroid arm skeleton.  相似文献   

3.
Traces of skeletal response to trauma are poorly documented for early (i.e. Paleogene, 66–23 Ma) penguins (Sphenisciformes) and infectious diseases that afflicted these seabirds have not been previously put on record. We report osteomyelitis (OM), typically a bacterial infection of bone, in a proximal pedal phalanx of a ‘giant’ penguin from the Eocene (56–34 Ma) of West Antarctica. Osteomyelitis had apparently complicated healing of a fracture. The injury left an oblique scar within the proximal aspect of the plantar surface, resulting in deformation of the articular surface. The recognised evidence of OM includes characteristic periosteal reaction as well as focal bone-loss and necrosis.  相似文献   

4.
5.
We report on the results of applying the so-called lateral angle method for sex determination on skeletal remains. The lateral angle denotes the angle of the internal auditory canal in relation to the medial surface of the petrous part of the temporal bone. The method involves making a small cast of the proximal part of the internal acoustic canal and determining the angle at which the canal opens up to the surface of the petrous bone. The method has the great advantage of utilizing one of the sturdiest bone elements of the human skeleton, and may thus be especially suited for analyses of very fragmented skeletal remains or cremated bones, where the petrous bone may still be readily recognizable. The method was tested using a forensic sample of 113 petrous bones with known sex. Intra- and interobserver testing was also performed. We found a statistically significant difference in angle size between males and females (mean angle size of males, 39.3 degrees ; mean angle size of females, 48.2 degrees ; P < 0.001). There was no bilateral difference in angle size. In blind trials, 83.2% of petrous bones were assigned to the correct sex. We also tested the lateral angle method against an archaeological skeletal sample. True sex was not known for this sample; instead, sexing had been carried out by assessing pelvic and cranial morphology in independent trials. We found a higher concordance between the lateral angle and "pelvic" sex than for lateral angle and "cranial" sex. Finally, we note that subadult sexing may also be possible with this method.  相似文献   

6.
A proximal humerus fragment referred to as Azhdarchidae indet. from the Rybushka Formation (Upper Cretaceous, Lower Campanian) of the Beloe Ozero locality in Saratov Region is described. The proximal articular surface is not saddle-shaped, has a weakly convex profile in the frontal section. The most posteriorly projecting part of the proximal articular surface is displaced ventrally. A large pneumatic foramen is located on the anterior surface ventral to the base of deltopectoral crest and close to the proximal articular surface. The humeral head is slightly declined from the diaphysis and only slightly overhangs the diaphysis posteriorly. This proximal humerus fragment possibly belongs to Volgadraco bogolubovi Averianov, Arkhangelsky et Pervushov, 2008, described from the Rybushka Formation of the Shirokii Karamysh 2 locality in Saratov Region.  相似文献   

7.
Although adult skeletal morphological variation is best understood within the framework of age-related processes, relatively little research has been directed towards the structure of and variation in trabecular bone during ontogeny. We report here new quantitative and structural data on trabecular bone microarchitecture in the proximal tibia during growth and development, as demonstrated in a subadult archaeological skeletal sample from the Late Prehistoric Ohio Valley. These data characterize the temporal sequence and variation in trabecular bone structure and structural parameters during ontogeny as related to the acquisition of normal functional activities and changing body mass. The skeletal sample from the Fort Ancient Period site of SunWatch Village is composed of 33 subadult and three young adult proximal tibiae. Nondestructive microCT scanning of the proximal metaphyseal and epiphyseal tibia captures the microarchitectural trabecular structure, allowing quantitative structural analyses measuring bone volume fraction, degree of anisotropy, trabecular thickness, and trabecular number. The microCT resolution effects on structural parameters were analyzed. Bone volume fraction and degree of anisotropy are highest at birth, decreasing to low values at 1 year of age, and then gradually increasing to the adult range around 6-8 years of age. Trabecular number is highest at birth and lowest at skeletal maturity; trabecular thickness is lowest at birth and highest at skeletal maturity. The results of this study highlight the dynamic sequential relationships between growth/development, general functional activities, and trabecular distribution and architecture, providing a reference for comparative studies.  相似文献   

8.
Mature pollen grains ofNymphaea mexicana have a verrucate proximal surface, a psilate distal surface and an anazonasulculus (encircling-sulcate aperture). The developmental events of microspores and tapetal cells were observed with TEM and SEM. Radially oriented substructural elements are seen in the microspore surface coating ofNymphaea mexicana from the early tetrad stage through the whole exine development. These elements, being the structural units of the microspore surface matrix (glycocalyx), are associated with sporopollenin precursor accumulation. In young free microspores, radially oriented elements are observed at both proximal and distal poles as a palisade between the endexine and plasmalemma.—Several points are discussed: (1) the initial and mature forms of exine substructure elements; (2) the significance of exine substructure for realisation of morphogenetic processes; (3) the ways by which verrucate and psilate sculpture patterns are developed.  相似文献   

9.
Growth series of femora, tibiotarsi, and humeri of the Canada goose Branta canadensis were examined to evaluate whether bone surface textures are reliable indicators of relative age and skeletal maturity in this taxon. The relationship between surface texture and skeletal maturity was analysed by comparing element texture types with both size-based and size-independent maturity estimates. A subsample of hindlimb elements was thin sectioned to observe histological structures underlying various surface textures. Three relative age classes of elements are identifiable based on surface texture. Juvenile and subadult bone textures have fibrous and/or porous areas on the bone shaft and are distinguished by the presence (in juveniles) or absence (in subadults) of coarse longitudinal striations in proximal and/or distal regions. Adult bone texture lacks surface porosity. Immature textures are caused by channels in fibrolamellar bone intersecting the bone surface; the presence or absence of striations is determined by channel orientation. Mature textures may be underlain by fibrolamellar bone with little to no surface exposure of channels, or by lamellar bone deposited after rapid growth ceases. The utility of the textural ageing method appears intimately related to the uninterrupted determinate growth regime of Branta . This suggests that bone surface textures may prove useful as skeletal maturity indicators in both modern and fossil taxa with similar growth regimes, but may not necessarily be reliable for taxa with interrupted and/or indeterminate growth.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 133–168.  相似文献   

10.
A rare origin of the superior thyroid artery   总被引:1,自引:0,他引:1  
In the course of a classroom dissection of a negro male (height: 167 cm; weight: 56.8 kg), and anomalous right superior thyroid artery was noted. It arose from the common carotid artery 27 mm proximal to the bifurcation into external and internal carotids. Previous reports indicate that the incidence of origin of the superior thyroid from the common carotid or its bifurcation varies from 5 to 45%, depending on the population sampled. Moreover, a low origin is more common in females than males, and appears approximately twice as often on the left as on the right. Previous reports also indicate that the origin is only very rarely more than 1 cm proximal to the bifurcation, only one case having been reported of an origin 25 mm proximal. The present case appears to be the most proximal origin so far recorded, and the first far proximal origin in negroes. The implications of such a low origin for surgical approach to the thyroid are considerable.  相似文献   

11.
Compartmentalization of skeletal muscle by multiple motor nerve branches, named as neuromuscular compartment (NMC), has been demonstrated in animals as well as humans. While different functional roles among individual NMCs were reported in the animal studies, no studies have clarified the region-specific functional role within a muscle related with NMCs arrangement in human skeletal muscle. It was reported that the rectus femoris (RF) muscle is innervated by two nerve branches attached at proximal and distal parts of the muscle. The purpose of the present study is to clarify the possible region-specific functional role in the human RF muscle. Multi-channel surface electromyography (SEMG) were recorded from the RF muscle by using 128 electrodes during two different submaximal isometric contractions that the muscle contributes, i.e. isometric knee extension and hip flexion, at 20%, 40%, 60% and 80% of maximal voluntary contraction (MVC). Results indicated that the central locus activation for the amplitude map of SEMG during hip flexion located at more proximal region compared with that during knee extension. Significant higher normalized root mean square (RMS) values were observed at the proximal region during the hip flexion in comparison to those at middle and distal regions at 60% and 80% of MVC (p<0.05). In while, significant higher normalized RMS values were demonstrated at the distal region comparing with that at the proximal region at 80% of MVC (p<0.05). The results of the present study suggest possible region-specific functional role in the human RF muscle.  相似文献   

12.
Compliance of the subcutaneous lymph sacs of the hindlimbs increases from distal to proximal, as does limb segment mass (and presumably rate of lymph formation), for the semiaquatic bullfrog Rana catesbeiana and the cane toad Bufo marinus but not the aquatic clawed toad Xenopus laevis. Subcutaneous lymph-sac compliances vary interspecifically. The distal-to-proximal increase in lymph-sac compliance and estimates of lymph formation rate in the various hindlimb segments indicate that partitioning of hindlimb subcutaneous lymphatic sacs establishes a differential decrease in the intra-lymph-sac pressure for R. catesbeiana and B. marinus. These pressure differentials constitute a "compliance pump" that drives distal-to-proximal intersac lymph flow. The compliance pump alone explains lymphatic return for the aquatic frog X. laevis but does not explain how lymph would reach the dorsally located lymph hearts for terrestrial anurans, so we hypothesize that skeletal muscle pumps return lymph from the femoral and pubic lymph sacs to the lymph heart. This is a fundamentally different role of the subcutaneous lymph-sac system than has been previously proposed. We suggest that the more proximal subcutaneous lymph sacs are important for fluid storage because they have a relatively high compliance.  相似文献   

13.
Bilateral extirpation of the superior cervical sympathetic ganglia carried out during the first month after the birth of ratlings caused a delay in growth by 40-60%. Section of pre-ganglionic sympathetic fibers and also sham operations failed to lead to any significant changes. Normal growth and skeletal development were disturbed in gangliectomized rats: the zone of growth of the proximal end of the tibia was much narrower in the operated animals than in the intact ones and there was a delay in the spread of secondary ossification centres.  相似文献   

14.
Summary Marthasterias glacialis bears two kinds of pedicellariae. The straight pedicellariae are single and occur everywhere on the asteroid body surface except in the ambulacral groove. The crossed pedicellariae are clustered on mobile structures (the rosettes) build around marginal and abactinal spines.Basically, each pedicellaria has a head and a stalk. A skeleton occurs only in the pedicellarial head. It consists of two valves and a basal piece. Muscular bundles are anchored on these skeletal ossicles. The straight pedicellariae have two pairs of adductor muscles (the inner and the outer adductors) and one pair of abductor muscles, these latter being weakly developed. Longitudinal muscle fibers occur all along the stalk of straight pedicellariae. The crossed pedicellariae have two pairs of adductor muscles (the distal and the proximal adductors) and two pairs of abductor muscles (the distal and the proximal abductors). The proximal adductors of crossed pedicellariae are homologous to the stalk muscles of straight pedicellariae.The pedicellariae are able to react to direct and indirect tactile stimuli. There is a great deal of individual variation among pedicellarial responses. Moreover, the reactions occur at random and lack coordination. The seemingly aberrant behavior of the pedicellariae is interpreted as a preventive activity that protects the asteroid body surface against unwanted materials and organisms.  相似文献   

15.
A morphometric analysis of coated and uncoated structures found in the apical portion of principal cells from both the proximal and distal caput epididymidis has been carried out. Almost all endocytic, coated vesicles are found within 1 micron of the luminal surface of principal cells and the volume fraction of these and of uncoated vesicles is much greater in the proximal caput epididymidis. A serial section analysis indicated that many coated "vesicles" are tangentially sectioned coated pits and that a complex network of interconnected vesicular and tubular structures exists in the apical cytoplasm. Efferent duct ligation has no effect on the number of size of large coated and uncoated vesicles in either the proximal or distal caput epididymidis, indicating that substances delivered to principal cells from the lumen are not required to maintain the endocytic machinery. However, this treatment does result in a considerable increase in the number of large coated vesicles associated with the basal surface of principal cells from the proximal but not the distal caput epididymidis. The volume fraction of small, presumably exocytic, coated vesicles is significantly greater in the apical cytoplasm of cells from the distal caput epididymidis in control animals. Efferent duct ligation results in a significant increase in the volume fraction of these vesicles in the proximal but not distal caput epididymidis. These results show that there are marked differences in structure among principal cells from these two regions of the epididymis and that this may reflect differences in control and function.  相似文献   

16.
Microscopic observations were made of wear on the proximal surfaces of tooth crowns of Australian Aboriginals and whites. Typical wear facets displayed well-defined borders within which vertical or near vertical furrows, ranging from about 0.1 to 0.5 mm in width, were noted. Furrows on the interproximal surface of one tooth seemed to "interdigitate" with those on the proximal surface of the adjacent tooth. These observations are not consistent with the commonly-held view that interproximal tooth wear results from a buccolingual movement of adjacent teeth that maintain contact through mesial migration. Vertical or near vertical movement of teeth, possibly including a tipping action, must be an important factor, although the precise nature of the movement requires further investigation.  相似文献   

17.
Magnetoencephalographic source localisation techniques were used to measure oesophageal evoked magnetic fields from the cerebral cortex in 3 subjects. By using rapid balloon distension as a stimulus, a comparison of proximal and distal oesophageal cortical representation was made. The distal oesophagus was represented bilaterally in the insular cortex and SII as well as the inferior aspect of SI. The proximal oesophagus was represented unilaterally in superior and inferior SI, insular cortex and SII. Significantly, the superior portion of SI was consistently activated in subjects following stimulation of the proximal oesophagus, but similar activation was not found in response to distal stimulation. This may reflect the contribution from somatic afferent fibres in the striate muscle of the proximal segment. In conclusion, vagal afferents appear to contribute more to cortical activation following stimulation of the distal rather than the proximal oesophagus, while spinal afferents appear to be activated by both proximal and distal oesophageal stimulation.  相似文献   

18.
Herniation pits (HPs) of the femoral neck were first described in a radiological publication in 1982 as round to oval radiolucencies in the proximal superior quadrant of the femoral neck on anteroposterior radiographs of adults. In following early clinical publications, HPs were generally recognized as an incidental finding. In contrast, in current clinical literature they are mentioned in the context of femoroacetabular impingement (FAI) of the hip joint, which is known to cause osteoarthritis (OA). The significance of HPs in chronic skeletal disorders such as OA is still unclear, but they are discussed as a possible radiological indicator for FAI in a large part of clinical studies.In this paleoradiological study we examined a sample of mummies from the Capuchin Catacombs of Palermo, Sicily, by a mobile computed tomography (CT) scanner. Evaluation of the CT examinations revealed HPs in six out of 16 (37.5%) adult male mummies.The first aim of this study was to compare the characteristics of HPs shown in our mummy collection to the findings described in clinical literature. Thereby CT evaluation revealed that their osseous imaging characteristics are in accordance, consisting of round to oval subcortical lesions at the anterior femoral neck, clearly demarcated by a sclerotic margin.The second aim was to introduce HPs to the paleoradiological and paleopathological methodology as an entity that underwent a renaissance from an incidental finding to a possible radiological indicator of FAI in the clinical situation. As FAI plays an important role in the development of OA of the hip, which is a very common finding in human skeletal remains, HPs should always be considered in paleoradiological evaluation of hip joint diseases.  相似文献   

19.
This study quantifies the proximal articular surface shape of metatarsal (MT) 4 and MT 5 using three-dimensional morphometrics. Humans and apes are compared to test whether they have significantly different shapes that are skeletal correlates to comparative lateral foot function. In addition, shod and unshod humans are compared to test for significant differences in surface shape. The MT 4 fossils OH 8, Stw 628, and AL 333-160, and the MT 5 fossils AL 333-13, AL 333-78, OH 8, and Stw 114/115 are compared with humans and apes to assess whether they bear greater similarities to humans, which would imply a relatively stable lateral foot, or to apes, which would imply a flexible foot with a midfoot break. Apes have a convex curved MT 4 surface, and humans have a flat surface. The MT 4 fossils show greater similarity to unshod humans, suggesting a stable lateral foot. Unshod humans have a relatively flatter MT 4 surface compared with shod humans. There is much overlap in MT 5 shape between humans and apes, with more similarity between humans and Gorilla. The fossil MT 5 surfaces are generally flat, most similar to humans and Gorilla. Because of the high degree of shape overlap between humans and apes, one must use caution in interpreting lateral foot function from the proximal MT 5 surface alone.  相似文献   

20.
Morphogenetic competence (MC) exists in embryonic limb tissue once thought to have lost this property as a consequence of cytodifferentiation. By stage 25 of chick embryonic development, cells in the proximal core of the limb have committed to the cartilage phenotype and are producing their characteristic extracellular matrix. Recombinant limb-bud grafts constructed using isolated fragments of this tissue produce outgrowths with a limb-like skeletal pattern. Inclusion of proximal peripheral tissue in the grafts (with or without the polarizing tissue) inhibits outgrowth and skeletal morphogenesis, explaining the failure of earlier studies to reveal the MC of the proximal core (chondrogenic) cells. Since definitive chondroblasts express MC in more permissive surroundings, it appears that Zwilling's assertion, that the onset of cytodifferentiation causes the loss of MC, is an oversimplification and that complex tissue interactions are probably involved.  相似文献   

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