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101.
Our claim in this paper is that not being identified as the data source might cause harm to a person or group. Therefore, in some cases the default of anonymisation should be replaced by a careful deliberation, together with research subjects, of how to handle the issues of identification and confidentiality. Our prime example in this article is community participatory research and similar endeavours on indigenous groups. The theme, content and aim of the research, and the question of how to handle property rights and ownership of research results, as well as who should be in charge of the research process, including the process of creating anonymity, should all be answered, before anonymity is accepted.  相似文献   
102.
AIMS: Thermal inactivation of a mixture of five strains of Listeria monocytogenes, four strains of Escherichia coli O157:H7 and eight serotypes of Salmonella were compared with that of indigenous microflora in 75% lean ground beef. METHODS AND RESULTS: Inoculated meat was packaged in bags that were completely immersed in a circulating water bath and held at 55, 57.5 and 60 degrees C for predetermined lengths of time. The surviving cell population was enumerated by spiral plating heat-treated samples onto tryptic soya agar supplemented with 0.6% yeast extract and 1% sodium pyruvate. D-values, determined by linear regression, in beef were 77.49, 21.9, and 10.66 min at 55, 57.5, and 60 degrees C, respectively, for indigenous microflora (z = 5.81 degrees C). When either of the three pathogens were heated in beef, their D-values calculated were significantly lower (P < 0.05) than those of indigenous microflora at all temperatures. The slope of the thermal death time curve for L. monocytogenes, E. coli O157:H7 and indigenous microflora were similar. Using a survival model for nonlinear survival curves, the D1-values at all temperatures for L. monocytogenes were significantly higher (P < 0.05) compared with those for Salmonella serotypes, E. coli O157:H7 or indigenous microflora. However, higher recovery of a subpopulation of the indigenous microflora in beef exposed to heating at 55, 57.5 or 60 degrees C resulted in significantly higher (P < 0.05) D2-values at all three temperatures, compared with those of the three pathogens at the same test temperatures. CONCLUSIONS: If the thermal process is designed to ensure destruction of indigenous microbial flora, it should also provide an adequate degree of protection against L. monocytogenes, Salmonella serotypes or E. coli O157:H7. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study will assist the retail food industry in designing acceptance limits on critical control points that ensure safety, without introducing pathogens in a retail food environment, against L. monocytogenes, E. coli O157:H7 and Salmonella in cooked ground beef.  相似文献   
103.
Weed invasion in East Africa: insights from herbarium records   总被引:2,自引:0,他引:2  
The invasion process was documented from data on the labels of specimens stored in the East African Herbarium at the National Museums of Kenya. We analysed data from seven abundant alien plant species: Ageratum conyzoides L. (Asteraceae), Capsella bursa‐pastoris (L.) Med . (Brassicaceae ) , Datura stramonium L. (Solanaceae), Galinsoga parviflora Cav. (Asteraceae), Tagetes minuta L. (Asteraceae), Spergula arvensis L. (Caryophyllaceae) and Stellaria media (L.) Vill. (Caryophyllaceae) and compared these data with the spread of two native weeds: Cynoglossum coeruleum A.DC. (Boraginaceae) and Senecio discifolius Oliv. (Asteraceae). Although all investigated species had been already recorded before the Second World War, most specimens were collected between 1960 and 1980. This regional spread is correlated with a change in the agricultural systems of Kenya. The early records of alien weeds were restricted to higher altitudes. With the increasing human population and the associated increase of agricultural activities (e.g. irrigation in arid areas) the weed species from South America were able to spread to lower altitudes.  相似文献   
104.
This paper explores the scope and limitations of the economic valuation of biodiversity. How and why is this a useful exercise, but in what way is its usefulness constrained? These issues are discussed with particular reference to cultural values within the context of medicinal plants and phytopharmaceutical development. It is argued that whilst economic valuation is an extremely important and necessary aid to formulating conservation policy, it probably is not that informative about the motivations of people in their use of certain natural resources. This is especially true for the case of medicinal plants where belief systems about the causes of disease and therefore strategies for healing are important. The paper reviews studies which have attempted to put monetary values on medicinal plants and the option values of pharmaceuticals developed from plants, and discusses the applicability of the various approaches. The implications for conservation policy, and for likely collaboration between social and natural scientists is discussed.  相似文献   
105.
Established approaches to human hunting-gathering behavior have failed to integrate economic, political, and cultural motivations and to describe the rich array of meanings foragers derive from their practices. This essay examines an Australian Aboriginal community's foraging and settlement behavior. It argues that in order to understand the form and meaning of Australian Aboriginal economic practices, researchers must attend to local and regional economic, historical, and ecological constraints on foraging behavior. Equally important are local understandings of the productive potential of foraging activity, including a capacity to maintain the physical and mythic topology of the countryside and human body.I would like to thank Hal Conklin, Hal Scheffler, Bill Kelly, Susan Edmunds, and the anonymous reviewers atHuman Ecology for their insightful comments on drafts of this essay. Sigma Xi, The Scientific Research Council, the National Science Foundation (Grant No. BNS-88414363), and the Yale International and Areas Studies Program provided grants for various stages of my fieldwork.  相似文献   
106.
云南澜沧县陆稻品种资源多样性和原生境保护   总被引:9,自引:0,他引:9  
云南澜沧县不仅存在丰富的陆稻品种多样性和形态多样性,而且也存在陆稻生长环境和栽种管理方法的多样性,即山地民族在陆稻栽种方面的土著知识(indigenous knowledge,IK)多样性,讨论了由传统的刀耕火种生产制度过渡到现代固耕生产方式对陆稻生产及品种资源保存和保护的影响。提出了陆稻资源多样性保护的建议。  相似文献   
107.
Resurgent protectionists advocate a return to strict nature protection characterized by excluding most people from ecologically fragile areas. Certain groups of indigenous residents, namely those with low population densities, simple technologies, and subsistence economies, are seen as conservation friendly, but groups who are experiencing demographic growth, using Western technologies, and producing for the market are perceived as incompatible with biodiversity conservation. Using insights from common property theory as well as ethnographic observations of the Huaorani Indians of Ecuador, I illustrate how such assumptions constitute a conservation Catch-22 in which cultural conditions deemed compatible with biodiversity conservation are precisely those from which we would not predict conservationist practices to emerge. Romanticized conditions deemed harmonious with nature lack the incentives necessary for people to develop conservationist practices. Conservation is not a state of being, but a social process inextricably linked to social and political institutions influencing resource management.  相似文献   
108.
We describe a scenario of plant speciation across a relict forest archipelago in South Africa involving Pleistocene habitat expansion-contraction cycles, dispersal and adaptation to lower temperatures. This is the first population level study using molecular data in South African forests and has significant implications for conservation efforts in this area. Populations of the mesophytic forest floor herbs Streptocarpus primulifolius sensu lato and Streptocarpus rexii were sampled throughout their range in the naturally fragmented forests of eastern South Africa in order to investigate population genetic and phylogenetic patterns within the species complex, using nuclear microsatellites, nuclear ribosomal ITS (internal transcribed spacer) sequences and chloroplast genome sequences. S. primulifolius harbours high levels of genetic diversity at both the nuclear (mean HE = 0.50) and the chloroplast level (each population fixed for a unique haplotype). This is consistent with populations of these coastal species being Pleistocene relicts. In contrast, populations of S. rexii in cooler habitats at higher altitudes and lower latitudes harbour little or no nuclear genetic diversity (mean HE = 0.09) and most share a common chloroplast haplotype. The split of S. rexii from populations intermediate between the two species (S. cf. primulifolius) occurred between 0 and 0.44 million years ago according to the calibrated ITS phylogeny of the taxa. The low genetic diversity and homogeneity of S. rexii is congruent with this species having reached its current range during the Holocene. We found no evidence of monophyly of any of the taxa in this study, which we consider a consequence of recent evolution in a fragmented habitat.  相似文献   
109.
AIMS: To study the role of the indigenous yeast flora in traditional Irish cider fermentations. METHODS AND RESULTS: Wallerstein laboratory nutrient agar supplemented with biotin, ferric ammonium citrate, calcium carbonate and ethanol was employed together with PCR-restriction fragment length polymorphism analysis of the region spanning the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene in the identification of indigenous yeasts at the species level, from traditional Irish cider fermentations. By combining the molecular approach and the presumptive media it was possible to distinguish between a large number of yeast species, and to track them within cider fermentations. The Irish cider fermentation process can be divided into three sequential phases based on the predominant yeast type present. Kloeckera/Hanseniaspora uvarum type yeasts predominate in the initial 'fruit yeast phase'. Thereafter Saccharomyces cerevisiae type yeast dominate in the 'fermentation phase', where the alcoholic fermentation takes place. Finally the 'maturation phase' which follows, is dominated by Dekkera and Brettanomyces type yeasts. H. uvarum type yeast were found to have originated from the fruit. Brettanomyces type yeast could be traced back to the press house, and also to the fruit. The press house was identified as having high levels of S. cerevisiae type yeast. A strong link was noted between the temperature profile of the cider fermentations, which ranged from 22 to 35 degrees C and the yeast strain population dynamics. CONCLUSIONS: Many different indigenous yeast species were identified. The mycology of Irish cider fermentations appears to be very similar to that which has previously been reported in the wine industry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has allowed us to gain a better understanding of the role of indigenous yeast species in 'Natural' Irish cider fermentations.  相似文献   
110.
Large-scale economically-driven encroachments into tropical rainforest environments are major factors for disease emergence. A better understanding of the process of disease emergence can be best derived from a multilevel, transdisciplinary ecosystem approach that analyzes health data in its biological, ecological, social, and cultural context. Multiple methods, including ethnographic techniques, are recommended for such an approach. The value of this approach and methodology is presented in this article through a rapid health assessment case study of an unexplained fatal syndrome that occurred among the Secoya peoples of the Ecuadorian Amazon in 1999. This type of study is significant given the lack of health data for indigenous populations at risk of disease emergence. Moreover, indigenous cultures share a long-term, close relationship to the land and each other, which makes information about changes in their environment and health patterns highly salient to them. This local knowledge is of strategic value to researchers working on issues of environmental change and disease emergence.  相似文献   
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