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1.
ABSTRACT

The employment of timber pegs in timber structure joints is a widespread technology in the field of timber frame building in the United States, where the Timber Frame Engineering Council has published a special Standard to supplement the National Design Specification for Wood Construction. The authors have been studying the possibility of supplementing the Eurocode 5 design formulas, thought for timber joints with metal connectors, with specifications needed for a reliable design when employing timber pegs. The field of application envisaged is that of restoring timber structures and results obtained until now are quite encouraging. In this step of the research, more attention has been paid to deformation process: fir and chestnut samples have been tested to determine their dowel-bearing behavior with steel and ash timber peg while double-shear plane joints made of the same wood species, and fastened with steel as well as timber pegs, have been analyzed.  相似文献   
2.
This article examines the modernization of northern Finnish food culture, especially in 17th- and 18th-century urban Oulu, by applying the methods of archaeology and history research. During the 17th century, the food culture was still quite conservative. Coffee, sugar, wheat flour, and fruit began entering the diet of affluent northern Finnish people from the 18th century onwards. The food culture of Oulu inhabitants is studied by comparing dental material retrieved from Oulu Cathedral graveyard to data obtained from historical document sources. A comparison point to the early modern bone material of Oulu is provided by late Middle Ages material from Ii, which lies north of Oulu on the coast of the Gulf of Bothnia. Carbohydrate consumption is related to many dental conditions, such as caries and calculus, which can be traced in archaeological human skeletal remains. The diets of males and females, as well as the diets of adults and children, are compared, in order to retrieve information on the emerging consumption of sugar in different groups, such as gender and age groups. The relationship between carbohydrate consumption and class identity in northern Finland is discussed.  相似文献   
3.
The sacro-iliac joint has largely been excluded in studies of sex identification from the adult human skeleton. Yet this is a joint involved in the transmission of body weight and as such would be expected to exhibit sexual dimorphism. In addition, the auricular surface of the ilium tends to persist even in fragmented remains by virtue of its close proximity to the acetabulo-cristal buttress. The aim of this investigation was to assess the accuracy with which sex could be predicted from dimensions of the auricular surface of the ilium. Significant sex differences were found in the size and shape of the auricular surface. However, these differences were of insufficient magnitude to permit discrimination between the sexes with any acceptable degree of accuracy. Therefore, the auricular surface of the ilium is not recommended for the purpose of sex identification.  相似文献   
4.
This study investigates temporal changes in dietary practices in the Caribbean archipelago during the Ceramic Age (400 BC–AD 1500), through analyses of dental wear and pathology. Some previous studies in the region have suggested that diet and subsistence practices changed over time due to increasing sociopolitical complexity, climate change, or adaptation to island environments rich in marine resources. Both horticultural/agricultural intensification and increased marine focus of the diet over time have been posited, based among other things on faunal and botanical remains, and early ethnohistorical accounts. Local and micro‐regional stable isotope studies of temporal dietary variation have found few indications for change over time, and large regional isotope studies are still lacking. Dentitions from sites throughout the region dating to the Early Ceramic Age (400 BC–AD 600/800) and the Late Ceramic Age (AD 600/800–1500) were analysed in order to assess temporal differences. Intra‐individual rates of wear were calculated using the difference in degree of wear between the adjacent molars and the two groups were compared with principal axis analysis. Caries, antemortem tooth loss, abscesses and dental calculus were recorded per individual and per tooth/socket, and population caries and antemortem tooth loss rates were assessed and compared by age group, tooth class and sex. Comparisons between the two occupation periods revealed significant differences in the rate of dental wear and pathology, indicating a shift in dietary practices over time, coinciding with known social changes. The increase in pathology rates suggests a rise in the consumption of cariogenic foods or preparation techniques that increase cariogenicity. The decrease in rate of wear over time indicates a reduction in abrasivity of the diet. Together these data suggest that there was a growing focus on refined, cariogenic foods, likely horticultural/agricultural produce. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
5.
The purpose of this research was to explore the relationship between degenerative joint disease (DJD) in the apophyseal joints and intervertebral joints in the vertebral column and assess which vertebral DJD is the more reliable indicator of general activity‐related stress. We hypothesized that the more reflecting vertebral DJD for general activity‐related stress would appear to show a higher correlation with Schmorl's nodes (SNs). To test this hypothesis, we examined 125 individuals from Eunpyeong Cemetery (mid‐15th to early 20th centuries) in Seoul, Korea and analyzed the frequencies of two types of vertebral DJD and their relationship with SNs. Cross‐tabulation chi‐square tests were used to evaluate the significance of the differences between frequencies of vertebral pathologies. In conclusion, results revealed that the relationship between the two kinds of vertebral DJD appeared differently depending on vertebral region, joint type and sex. The test results of association between the two types of vertebral DJD were statistically significant at the cervical and lumbar regions of males. SNs appeared independently of the pattern of vertebral DJD in nearly all joints with the exception of a correlation between DJD in the intervertebral joints and SNs of the lumbar region in females. As indicated in some studies, this study reconfirmed that the differences in the two kinds of vertebral DJD result from differences in normal vertebral morphology and anatomical function. This study contributes to the overall discussion on the relationship between vertebral DJD and physical activity by showing that the detailed recording and understanding of the two types of vertebral DJD is required before they can be used convincingly in a study on activity‐related stress. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
6.
从老股票看20世纪50年代的股份制企业   总被引:2,自引:0,他引:2  
从已搜集到的20世纪50年代上海市的几种老股票来看,新中国成立初期的股份制企业至少存在三种类型。旧社会承继下来的资本主义性质的股份制企业是接受社会主义改造的重点对象和主角,通过实行“定息”,以“赎买”的方式,切断了所有制与经营者之间的联系,此时的股票与债券无异,股东与企业的关系是债权债务关系;农村的供销合作社和城市中的街道办股份制企业,与真正意义上的股份制企业相比都有很大的不同,它们的目的都是在抵制资本主义复辟和改变小生产方式的前提下发展社会生产力,目标是建成生产资料公有制的社会主义计划经济。  相似文献   
7.
1949年5月上海解放后,不同层次的私营金融业在走向公私合营的共同目标中,所需的时间、具体的过程有着较大的区别。上海私营金融业曾两次组织对生产与其他经济事业的联合放款,此外规模较大的银行较早实现了公私合营,而数十家中小行庄公司则通过组成四个联营集团进行多种业务的联合经营并逐步过渡到两个联合总管理处,实现了从业务到人事、财务、组织多种形式的联合管理,最后在条件成熟的时候与大银行共同组成统一的公私合营银行。政府对上海地区数量众多的私营金融机构采取了导向联放、联营和联管的循序渐进的谨慎政策,是符合整个中国金融业历史实际的正确之举,体现了中国私营金融业社会主义改造的历史必然性和复杂性。  相似文献   
8.
Dislocation is the most severe form of developmental dysplasia of the hip (DDH). It significantly impairs hip function in the young, and may lead to debilitating early‐onset osteoarthritis in adults. To our knowledge no thorough study of a large skeletal population has ever been undertaken to determine the wide range of diagnostic criteria for this condition in pathological specimens. To identify these criteria we have analysed the cases of developmental dislocation from a large series of 6000 individuals (6580 hips) from the medieval cemetery at Spitalfields in London, UK. We describe the changes at the true acetabulum, and have created a four‐stage classification of the false acetabulum. The skeletal response to the altered biomechanics and limb shortening that occurs in developmental dislocation is described in the pelvis, lower limb and spine. This includes asymmetric growth in childhood, and asymmetric degenerative change in adulthood. We conclude with a discussion of the clinical literature on developmental dislocation of the hip that will aid palaeopathologists to estimate the symptoms that an excavated individual may have experienced during their lifetime. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
9.
This study examines possible morphological variation in the knee joint of Homo sapiens with increasing age in ostensively healthy and non‐pathological distal femora and proximal tibiae. Throughout the lifetime of each individual, the hard tissue of the knee undergoes considerable remodelling as a response to biomechanical stresses, changes in bone microarchitecture and reduction of bone mineral content as a concomitant of ageing. The knee is also subject to greater levels of degenerative joint disease than any other joint. If death occurs whilst such diseases are in the earliest stages, initial bone changes may not be visually obvious in museum specimens. If such specimens are used for comparative analyses, it is hypothesised that changes might render it problematic if all ages are conglomerated into discrete samples. This study therefore investigates the degree to which the distal femur and proximal tibia change shape during ageing and, if changes are present, whether they are expressed similarly in males and females. It also examines whether changes are of greater magnitude than those morphological differences which might exist between populations. In an example population of African‐Americans, results indicate that there is a statistically significant difference in shape between age groups and those differences become progressively greater between the youngest and oldest adults. Results also show that although morphological variation caused by ageing is apparent, those shape differences attributable to sexual dimorphism are more powerful. When two additional populations are analysed jointly with the African‐Americans (Caucasian Americans and the European Spitalfields sample), results indicate that inter‐population shape differences are considerably greater than differences caused by increasing age. Results imply that it is justifiable to combine specimens of all ages into discrete samples for comparative purposes. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
10.
A small pit in the articular surfaces of the third tarsometatarsal joint has been noted with particularly high frequency in North American Indians. This pit varies in depth, and covers most of the inferior third of the articular surfaces of the third metatarsal and the lateral cuneiform; it is accompanied by remodelling of the inferior surfaces of the bones involved. In the present study, patterns of occurrence are examined in a prehistoric skeletal population from west-central Illinois. This population is extremely well preserved, enabling a thorough examination of feet as well as hands for most individuals. The sample included 496 adults and juveniles above the age of 6 years. Of this total population, 18 per cent exhibit the variation, which occurs more frequently in females and is unrelated to size. Furthermore, 29 per cent of the individuals in which it occurs exhibit this variant only unilaterally, with no significant side differences. Various lesions, trauma and acquired or activity-related aetiologies are explored, as are the patterns of sex association, occurrence near an area of ligamentous attachment and lack of age and size association. It is hypothesized that a discrete genetic trait is represented in the third tarsometatarsal joint of this population in the form of an anomalous interosseous plantar ligament. © 1997 by John Wiley & Sons, Ltd. Int. J. Osteoarchaeol., 7 : 124–132 (1997) No. of Figures: 3. No. of Tables: 2. No. of References: 26.  相似文献   
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