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《Plains anthropologist》2013,58(93):195-212
Abstract

A variety of quite different theories and models concerning the fracture of solids and the behavior of solids under stress have been developed by physical scientists. On the basis of their work, 19 variables are identified that are likely to be important in studying the mechanics of stone flaking. These variables fall into three classes: (1) properties of the material being fractured; (2) properties of the flaking device; and (3) variables relating to the experimental situation. A lack of knowledge concerning the physical properties of many common stone tool materials seriously hinders the direct application of theories of stress and fracture to practical archaeological problems. However, the work of physical scientists may still suggest approaches to problems in lithic technology and variables which may be worth examining.  相似文献   

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《Endocrine practice》2015,21(3):275-279
ObjectiveInjectable osteoporosis drugs are increasing in popularity due to their efficacy and convenient administration. In this retrospective comparison of the two available treatments, denosumab (Prolia®) and zoledronic acid (ZA, Reclast®), we aimed to determine and compare the efficacy and tolerability of denosumab and ZA.MethodsThe charts of patients who received denosumab and ZA at Loyola Hospital were reviewed, and adverse events were noted. Of primary interest were myalgias, flu-like symptoms, back pain, and fractures. A questionnaire regarding the efficacy, tolerability, and treatment cost supplemented this chart review in a subset of study participants. Bone mineral density (BMD) changes, bone turnover markers, and questionnaire results were also compared.ResultsThe study cohort consisted of 107 patients (51 denosumab, 56 ZA). The denosumab group had a greater mean increase in spine BMD at 1 year (0.060 g/cm2) than the ZA group (0.021 g/cm2; P = .04). The change in femur and spine BMD at 1 year were not significantly different between the 2 groups. The ZA group had a significantly greater incidence of mild flu-like symptoms (29% ZA group vs. 0% denosumab group; P = .04).ConclusionThe denosumab group had a higher mean increase in spine BMD, and the ZA group had a higher incidence of flu-like symptoms, but the study groups were statistically similar in terms of patient satisfaction. As denosumab is still a relatively new therapy, there were a limited number of patients with posttreatment data available for comparison. As more posttherapy data become available, it can be further investigated. (Endocr Pract. 2015;21:275-279)  相似文献   

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Drawing on research conducted among patients in Ireland, this article examines the narrative constructions of chronic kidney failure and explores the ways in which patient narratives cross-cut and subvert modernist medical constructions of transplantation as a therapeutic outcome, an endgame, a “gift of life.” In experience, patients dismantle this construction structure by emplotting their stories around the painful lack of an ending, ardently brought to bear by the lived realities of immunosuppressant drug therapy, the silent fears of graft rejection, and the isolation of recipiency. They articulate, instead, stories that disclose a multi-directional flow between past and future therapeutic interventions, between the altering nature of the renal body and personal experience. These storied dimensions are phenomenologically embedded in the sensory and temporal aspects of this condition as essential elements of chronic illness and as organizational properties of patient narratives.  相似文献   

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Male-centred aspects of political behaviour have generally remained the explanatory and interpretive focuses in analyses of the social organization of African pastoralists. While recent work on African pastoralists has shed increasing light on the lives of women, I argue that key assumptions underlying anthropological models of male dominance in these societies have been insufficiently challenged. Drawing on recent approaches in gender and social organization that highlight the mutual constitution of domestic and political domains, I examine comparative material from two well-known pastoralist societies: the Samburu of northern Kenya and the Nuer of southern Sudan. In doing so, I suggest strong linkages between male-dominated 'political spheres' and areas of domestic life in which the role of women is more significant – particularly processes of domestic food distribution. In re-examining central facets of Samburu politics – which are best known through Paul Spencer's seminal analysis of the gerontocratic aspects of Samburu political life – I suggest that the status and identities of Samburu men are in fundamental ways defined through their relationship to women as providers of food within Samburu households. Comparative material from the Nuer suggests, additionally, the strategic use of food by women in influencing male 'political spheres'. In comparing these cases, I suggest a more general model through which domestic processes of food allocation as realms of female-centred social action may be seen to play a central role in the forms and processes of pastoral 'political' life.  相似文献   

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The interrelationships within the clade comprised of turtles, pareiasaurs, and procolophonid-like taxa are investigated via a cladistic analysis incorporating 56 characters. A single most parsimonious tree was found (80 steps, c. i. = 0·8) in which the successive outgroups to turtles are: pareiasaurs, Sclerosaurus, lanthanosuchids, procolophonoids (=Owenetta, Barasaurus and procolophonids), and nyctiphruretians (= nycteroleterids). Thus, as suggested recently by other workers (Reisz, in Fischman, 1993) turtles are the highly modified survivors of a radiation of poorly-known reptiles commonly called ‘parareptiles’. Pareiasaurs are united with turtles on the basis of twenty unambiguous derived features which are absent in other basal amniotes (=‘primitive reptiles’) and reptiliomorph amphibians: for example, the medially located choana, enlarged foramina palatinum posterius, blunt cultriform process, fully ossified medial wall of the prootic, opisthotic-squamosal suture, lateral flange of exoccipital, loss of ventral cranial fissure, thickened braincase floor, ‘pleurosphenoid’ ossification, reduced presacral count, acromion process, trochanter major, reduced fifth pedal digit, and presence of transverse processes on most caudals. Recent phylogenetic proposals linking turtles with captorhinids, with dicynodonts, and with procolophonoids are evaluated. None of the proposed traits supporting the first two hypotheses is compelling. The procolophonoid hypotheses is supported by only one synapomorphy (the slender stapes). All other synapomorphies proposed in favour of the above groupings either occur in many other primitive amniotes, or are not primitive for turtles, or are not primitive for the proposed chelonian sister-group. Nyctiphruretus and Lanthanosuchids and nycteroleterids, often considered to be seymouriamorph amphibians, are demonstrated unequivocally to be amniotes. The ‘rhipaeosaurs’, currently considered to be pareiasaur relatives, are shown to be a heterogenous assemblage of seymouriamorphs, therapsids and nycteroleterids. The phylogeny proposed here indicates that many of the traits of the earliest known turtle, Proganochelys, previously interpreted as unique specialisations, also occur in pareiasaurs and other near outgroups of turtles, and must instead represent the primitive chelonian condition: for example, the wide parietals and the short quadrate flange of the pterygoid. The sequence of acquisition of chelonian traits is discussed: many features once thought to be diagnostic of turtles actually characterize larger groupings of procolophonomorphs, and must have evolved long before the chelonian shell appeared. These traits include most of the chelonian-pareiasaur synapomorphies listed above, and many others which characterize more inclusive groupings found in this analysis. In putting Proganochelys much closer to the main line of chelonian evolution, in elucidating the sequence of acquisition of chelonian traits, and in reducing greatly the number of differences between turtles and their nearest relatives, this study helps bridge one of the major gaps in the fossil record. The failure of previous cladistic analyses to identify correctly the nearest relatives of turtles is attributed to biased character selection, caused by an over-reliance on cranial characters deemed ‘important’ by earlier workers, and by a tendency to shoehorn ‘parareptile’ taxa into phylogenies derived from analyses restricted to ‘mainstream’ groups such as synapsids, diapsids, turtles, and ‘captorhinomorphs’. Many of the synapomorphies that resolve turtle origins are postcranial, and the three nearest outgroups to turtles are all highly bizarre groups which were dismissed as ‘too specialized’ by early workers and continued to be inadequately assessed even by workers using a cladistic framework.  相似文献   

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《Endocrine practice》2018,24(1):6-13
Objective: To determine the prevalence of obesity according to the American Association of Clinical Endocrinologists/American College of Endocrinology (AACE/ACE) framework based on a complications-centric model with further application of the Cardiometabolic Disease Staging (CMDS) system in a Venezuelan population.Methods: A total of 1,320 adults were randomly selected from 3 regions. The AACE/ACE framework definitions were as follows: overweight, body mass index (BMI) 25 to 29.9 kg/m2 and no obesity-related complications (ORC); obesity stage 0, BMI ≥30 and no ORC; stage 1, BMI ≥25 and 1 or more mild-to-moderate ORC; and stage 2, BMI ≥25 and 1 or more severe ORC. CMDS definitions were as follows: stage 0, no metabolic syndrome (MS) components; stage 1, 1 to 2 MS components without impaired fasting glucose (IFG); stage 2, IFG or ≥3 MS components but without IFG; stage 3, IFG and MS; and stage 4, type 2 diabetes (T2D) or cardiovascular disease.Results: The mean age was 44.8 ± 0.4 years, and 68.5% were female. The prevalence of obesity according to the AACE/ACE framework was 63.1%: overweight 3.0% (95% confidence interval &lsqb;CI]: 2.1–3.9); obesity stage 0: 0.1% (0.07–0.27); obesity stage 1: 26.6% (24.2–29.0); and obesity stage 2: 36.4% (33.8–39.0). Most subjects with a BMI <25 were CMDS 0 or 1. In those with BMI ≥ 25, only 4.6% were CMDS 0. The prevalence of obesity according to the World Health Organization (WHO, BMI ≥30) was 29.3% (24.7–33.7).Conclusion: In a general population study, applying the AACE/ACE framework for obesity and CMDS increased the detection of ORC and therefore higher risk subjects compared to classic anthropometric measurements.Abbreviations: AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; BMI = body mass index; CMDS = Cardiometabolic Disease Staging; DALY = disability-adjusted life years; LA = Latin America; MS = metabolic syndrome; ORC = obesity-related complications; WC = waist circumference; WHO = World Health Organization  相似文献   

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Over 90% of the prey of the Short-eared Owl in Britain and Ireland comprises small mammals, particularly the Short-tailed Vole. Birds, Wood Mice and Brown Rats are of secondary importance and, with Pygmy Shrews, may be the staple foods on islands lacking voles.  相似文献   

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目的探讨DFR与CR联合运用在静脉尿路造影中的应用价值。资料与方法综合DFR与CR的优点对1007例静脉尿路造影效果分析。结果数字透视与数字摄影相结合的方法在静脉尿路造影中效果明显。结论数字透视与数字摄影联合运用的方法应用于静脉尿路造影具有应用前景。  相似文献   

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