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 共查询到11条相似文献,搜索用时 15 毫秒
1.
ABSTRACT  Physical anthropologist Aleš Hrdlička is often remembered as an institutional and political opponent of Franz Boas and as an advocate of racial typology against which the Boasian antiracialist position in American anthropology developed. I argue that Hrdlička nonetheless also has more subtle lessons to offer about the political limits of Boasian antiracism. Examining Hrdlička's engagement with the politics of Europe and East Asia from the 1920s to the 1940s, particularly with the intellectual grounding of Japanese imperialism, I suggest that he was perhaps uniquely cognizant of a "second problem of race in the world"—the racist assimilationism of the Japanese empire—vis-à-vis the Boasian grasp of race, rooted in a response to U.S. and Nazi racisms, as a category of invidious difference. Moreover, I contend that the lacuna that Hrdlička helps us identify has continued to haunt the discipline at certain key moments of Boasian critique of other ideological forces.  相似文献   

2.
This article compares the status of "culture" as a politically engaged concept in Franz Boas's time and in our own time. Taking a Boasian approach to "neo-Boasianism," I examine the limits of this comparability in order to shed light on the nature of public culture-talk today and to identify dimensions of the Boasian concept of "culture" particularly relevant to a contemporary anthropology.  相似文献   

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A compound that can enhance the apparent synthesis of acetylcholine in cultured explants of the medial septal nucleus has been purified from rat brain and identified as phosphoethanolamine. Acetylcholine synthesis is stimulated two- to threefold in cultures grown for 5 days in the presence of phosphoethanolamine, ethanolamine, or cytidine 5'-diphosphoethanolamine at concentrations above 100 microM. This effect appears to result from an increase in the accumulation of choline via the high-affinity, sodium-dependent uptake mechanism. The development of choline acetyltransferase activity is not affected. Phosphoethanolamine and ethanolamine seem to enhance the ability of developing cholinergic neurons to utilize choline accumulated via the sodium-dependent high-affinity choline uptake mechanism for the preferential production of acetylcholine without increasing the general metabolism of the cultures. Choline itself and its related derivatives are not stimulatory for these effects.  相似文献   

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Children with language impairments have limitations of phonological short-term memory (STM) and have distinctive problems with certain aspects of grammar. Both deficits have been proposed as phenotypic markers of heritable language impairment. We studied 173 twin pairs, selected to be over-representative of children with risk of developmental language impairment, using a battery of standardized language and intelligence tests, a test of nonword repetition to index phonological STM and two elicitation tasks to assess use of verb tense marking. As predicted, the phonological STM and the verb tense measures both discriminated children with risk of language impairment from low risk children, and DeFries-Fulker analysis showed that impairments on both tasks were significantly heritable. However, there was minimal phenotypic and etiological overlap between the two deficits, suggesting that different genes are implicated in causing these two kinds of language difficulty. From an evolutionary perspective, these data are consistent with the view that language is a complex function that depends on multiple underlying skills with distinct genetic origins.  相似文献   

7.
Xiang ZF  Huo S  Xiao W  Cui LW 《动物学研究》2010,31(6):645-650
黑白仰鼻猴(Rhinopithecus bieti)是仅存于滇西北和藏东南的横断山脉的濒危灵长类动物,目前仅有野外15群约2500只个体,并且西藏红拉雪山自然保护区的小昌都群也许是自1988年调查以来唯一数量保持稳定的种群。通过调查访问、以及分析社会经济数据中隐含的保护信息,该文通过实例研究探讨了传统文化和社会经济发展模式对红拉雪山自然保护区小昌都猴群的影响,试图探讨传统文化和人类活动对该猴群种群保持稳定的正面影响:1)研究结果表明传统的生产方式对黑白仰鼻猴的生境保护有益,例如主要依靠畜牧业和非木材的林产品而不是毁林开荒种植青稞;2)受印度教和佛教影响的藏传佛教对生灵的敬畏,避免当地村民对黑白仰鼻猴的猎杀;3)一妻多夫的大家庭,其人均资源消耗(特别是薪柴,建房木材等)明显比一夫一妻的小家庭少,这种婚俗也许可以缓解人类索取相应自然资源时对黑白仰鼻猴的生境破坏。因此,考虑到小昌都是唯一种群稳定的群,我们认为是当地的社会生产方式、宗教文化以及婚俗习惯让小昌都群长期维持在该生境的最大容纳量。  相似文献   

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Ovariectomy (OVX) in rats results in increased bone turnover and decreased bone volume and bone mineral density when measured in the metaphyses of long bones. We have investigated the effects of OVX on changes in the number of progenitors in cell populations derived from the metaphyseal bone of femurs of ovariectomized rats at 12 months of age, by using colony assays, bone nodule assays, and limiting dilution analysis at 1.5 and 9 months post-OVX. We have also measured histomorphometric parameters of bone formation and resorption in the corresponding tibia at the same time-points. A significant increase, as shown by bone nodule assays and limiting dilution analysis, occurs in the number of progesterone- and dexamethasone-responsive osteoprogenitors in cell populations isolated from ovariectomized rats at the 9-month post-OVX time-point. Progesterone-responsive osteoprogenitors are also increased at 1.5 months post-OVX. The number of fibroblast colony-forming units does not change. Histomorphometry has shown that OVX causes an increase in osteoblast surfaces, mineralizing surfaces, and bone formation rate at both 1.5 and 9 months post-OVX. The mineral apposition rate is increased at 1.5 months post-OVX. OVX also increases parameters of bone resorption at both time-points, the net result being a decrease in bone mineral density and cancellous bone volume at 9 months post-OVX. Thus, OVX in rats at 12 months of age is associated with an increase in the number of both progesterone- and dexamethasone-responsive osteoprogenitors 9 months post-OVX; this corresponds with increases in the histomorphometric parameters of bone formation.  相似文献   

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The turnover of mouse intestinal brush border membrane enzymes has been studied by kinetic analysis of the evolution of enzyme activities during organ culture. By comparing the results obtained in these studies with the predictions from a mathematical model of enzyme synthesis and degradation in orgen cultures, it has been possible to reach the following conclusions: (1) There is no degradation of brush border membrane enzymes during culture and the rate of synthesis of each enzyme is directly measurable from the kinetics of total enzyme accumulation (tissue + media). (2)_Brush border membrane enzymes are released in culture media by two complementary processes. The first one involves a differential solubilization of enzymes but its exact nature cannot be exactly stated. The second one involves a microvesiculation of brush border membranes, the importance of which in vivo is seen in the possible conciliation between unitary membrane synthesis and heterogeneous turnover of membrane components.  相似文献   

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将芥形橐吾(Ligularia brassicoides Hand.-Mazz.)、岷县橐吾(L. ianthochaeta C. C. Chang)和半裂橐吾(L. paradoxa Hand.-Mazz. var. palmatifida S. W. Liu  相似文献   

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To increase the understanding of poplar and willow perennial woody crops and facilitate their deployment for the production of biofuels, bioproducts, and bioenergy, there is a need for broadscale yield maps. For national analysis of woody and herbaceous crops production potential, biomass feedstock yield maps should be developed using a common framework. This study developed willow and poplar potential yield maps by combining data from a network of willow and poplar field trials and the modeling power of PRISM‐ELM. Yields of the top three willow cultivars across 17 sites ranged from 3.60 to 14.6 Mg ha?1 yr?1 dry weight, while the yields from 17 poplar trials ranged from 7.5 to 15.2 Mg ha?1 yr?1. Relationships between the environmental suitability estimates from the PRISM‐ELM model and results from field trials had an R2 of 0.60 for poplar and 0.81 for willow. The resulting potential yield maps reflected the range of poplar and willow yields that have been reported in the literature. Poplar covered a larger geographic range than willow, which likely reflects the poplar breeding efforts that have occurred for many more decades using genotypes from a broader range of environments than willow. While the field trial data sets used to develop these models represent the most complete information at the time, there is a need to expand and improve the model by monitoring trials over multiple cutting cycles and across a broader range of environmental gradients. Despite some limitations, the results of these models represent a dramatic improvement in projections of potential yield of poplar and willow crops across the United States.  相似文献   

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