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981.
Proximal radio‐ulnar synostosis (RUS) may occur congenitally, either as an isolated condition or as part of a syndrome, or it may occur as a secondary complication of forearm trauma. We provide a key for the differential diagnosis of congenital versus traumatic RUS, and for differentiation between types of congenital RUS. Congenital cases (CRUS) include absence of fracture, radial head abnormalities, radial shaft bowing, and absence of a sigmoid notch, whereas post‐traumatic RUS results from either radial neck fracture or evulsion of the biceps brachii, followed by ossification of the resulting haematoma or of the interosseous (IO) membrane. Congenital cases include those which result from incompetent differentiation of the single mesenchymal mass that gives rise to the radius and ulna (Type I) and those that result from radial head dislocation in utero, resulting usually from humeral or ulnar defects (Type II). Type II CRUS can be differentiated by the presence of radial overgrowth, among other factors. Following these guidelines, we describe and compare the morphology of three congenital cases from North America. Two present bony fusions and one a functional fusion with radial overgrowth. In each case, CRUS significantly limits both supination and pronation. Despite differences among the cases, several morphological accommodations are shared as a result of fixation in the neutral (semi‐pronated) position. These changes include the ventral migration of the IO crests of the ulnae and enlargement of the dorsal tubercles of the radius. Understanding the pattern of accommodations made in the face of compromised function ultimately increases our understanding of the patterns of growth in normal functional regimes. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
982.
B. F. Leach J. M. Davidson L. M. Horwood 《International Journal of Osteoarchaeology》1997,7(5):481-496
Twenty-four measurements were taken on five of the paired cranial bones and the otoliths of a modern sample of 177 blue cod. Parapercis colias. Regression analysis was performed on these measurements to estimate live fork length and ungutted weight. A number of regression models were examined (linear, logarithmic, exponential and power curve) to work out the optimum estimator for each bone measurement. It was found that live fork length of this species can be estimated with a standard error of less than ±28 mm, and the weight to less than ±140 g. Coefficients are provided for 48 equations linking bone size to live characteristics. This is followed by a study of blue cod from an archaeological site at Waihora in the Chatham Islands. Measurements were made on 8036 archaeological bones with a minimum number of individuals of 2547. It was found that the blue cod catch had near normal characteristics, with a mean fork length of 327 mm and SD of 57 mm. The mean body weight was estimated at 569 g. The usable meat weight represented by these fish is estimated to be 1.0 t. © 1997 John Wiley & Sons, Ltd. 相似文献
983.
The first data on bird hunting by the ancient people from El Hierro island are given here. Ninety-three bones have been examined from a cave situated in the archaeological site of Guinea. The majority of the bones are broken, burned and some of them have cuts showing human exploitation. There are species that have been eaten from the lower levels to the present day (Calonectris diomedea, Columba sp. and Corvus corax), one species that does not now live on El Hierro (cf. Pyrrhocorax pyrrhocorax), and an extinct species (Coturnix gomerae). © 1997 John Wiley & Sons, Ltd. 相似文献
984.
Christopher M. Stojanowski 《International Journal of Osteoarchaeology》2002,12(4):259-278
In this paper I evaluate the effects of wave and tidal erosion on element‐specific measures of phenotypic variability. Previous research has found a high correlation between skeletal weight, shape, and density and the transport potential of an element exposed to hydrodynamic forces. However, no previous studies have attempted to address the issue of within‐element sorting based on selective removal of only the smallest members of a given element class. I evaluate this hypothesis using a human skeletal sample from Bird Island (8DI52) located in Dixie County, Florida. This sample comprises two components, an eroded sample that was exposed during severe storm and tidal activity, and an uneroded sample excavated from primary context. The measurement‐specific means for the subcomponents were compared using Student's t and Wilcoxon tests and variability differences were evaluated based on standard deviations, coefficients of variation, and maximum/minimum indices. The data included maxillary and mandibular tooth dimensions and postcranial metrics. No evidence for selective winnowing based on within‐element size was found in this data set. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
985.
M. Steyn J. H. Meiring W. C. Nienaber M. Loots 《International Journal of Osteoarchaeology》2002,12(4):291-296
Unusually large fontanelles were found in four skeletons of children from a cemetery in the North West Province of South Africa. These remains date from the last decade of the 19th and first half of the 20th century. Three small infants (two of about nine months, and one of about six months) and one child (of about three years) were affected. In the case of the three‐year‐old child pathologic changes were evident on the rest of the skeleton, which probably resulted in the delayed closure. The cause of the unusually large fontanelles in the other three individuals is less clear. Some possibilities are discussed, but it seems as though general hardship and malnutrition, congenital syphilis or other infectious diseases like rubella syndrome may be involved. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
986.
Knowledge of Sicilian biology during the past is very important in understanding the complex processes that characterized the population of the Mediterranean Basin. The problem of the first Greek settlement in Sicily is essential in understanding and reconstructing the indigenous biological tissue of an island that was and still is a fundamental crossroads for migratory strategies. In this research we studied ten Sicilian series chronologically attributed to the second and first millennium BC , using discrete cranial traits. The results show that the first biologically significant Greek presence in eastern Sicily could go back to the Bronze Age, while the cosmopolitan Hellenistic city of Syracuse showed the nature of the biological pattern during the first millennium BC . Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
987.
Petrological and geochemical evidence is presented on the occurrence of aegirine in the Palaeoproterozoic Hotazel iron‐formation, which hosts the giant manganese deposits of the Kalahari manganese field, South Africa. The mineral has an essentially pure Na end‐member composition and occurs sporadically in iron‐formation immediately bordering the manganese ore beds. The development of aegirine appears to have taken place due to the action of late‐infiltrating, saline hydrothermal fluids at the expense of a pre‐existing, binary quartz–hematite assemblage. It is proposed that such a process would have overprinted (and therefore post‐dated) a spatially more extensive, low‐temperature alteration event which brought about thorough carbonate leaching, oxidation and residual enrichment of metals in the Hotazel iron–manganese rocks. 相似文献
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