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21.
BackgroundDiagnosis of cancer through an emergency presentation is associated with worse clinical and patient experience outcomes. The proportion of patients with cancer who are diagnosed through emergency presentations has consequently been introduced as a routine cancer surveillance measure in England. Welcome reductions in this metric have been reported over more than a decade but whether reductions reflect true changes in how patients are diagnosed rather than the changing case-mix of incident cohorts in unknown.MethodsWe analysed ‘Routes to Diagnosis’ data on cancer patients (2006–2015) and used logistic regression modelling to determine the contribution of changes in four case-mix variables (sex, age, deprivation, cancer site) to time-trends in emergency presentations.ResultsBetween 2006 and 2015 there was an absolute 4.7 percentage point reduction in emergency presentations (23.8%–19.2%). Changing distributions of the four case-mix variables explained 19.0% of this reduction, leaving 81.0% unexplained. Changes in cancer site case-mix alone explained 16.0% of the total reduction.ConclusionChanges in case-mix (particularly that of cancer sites) account for about a fifth of the overall reduction in emergency presentations. This would support the use of adjustment/standardisation of reported statistics to support their interpretation and help appreciate the influence of case-mix, particularly regarding cancer sites with changing incidence. However, most of the reduction in emergency presentations remains unaccounted for, and likely reflects genuine changes during the study period in how patients were being diagnosed. 相似文献
22.
Lucas Molleman Eva van den Broek Martijn Egas 《Proceedings. Biological sciences / The Royal Society》2013,280(1757)
There is ample evidence that human cooperative behaviour towards other individuals is often conditioned on information about previous interactions. This information derives both from personal experience (direct reciprocity) and from experience of others (i.e. reputation; indirect reciprocity). Direct and indirect reciprocity have been studied separately, but humans often have access to both types of information. Here, we experimentally investigate information use in a repeated helping game. When acting as donor, subjects can condition their decisions to help recipients with both types of information at a small cost to access such information. We find that information from direct interactions weighs more heavily in decisions to help, and participants tend to react less forgivingly to negative personal experience than to negative reputation. Moreover, effects of personal experience and reputation interact in decisions to help. If a recipient''s reputation is positive, the personal experience of the donor has a weak effect on the decision to help, and vice versa. Yet if the two types of information indicate conflicting signatures of helpfulness, most decisions to help follow personal experience. To understand the roles of direct and indirect reciprocity in human cooperation, they should be studied in concert, not in isolation. 相似文献
23.
Several competing hypotheses have been put forward to explain why females of many species mate preferentially with males possessing the most conspicuous signals (e.g., ornaments, displays, or songs). We performed a laboratory experiment using two species of poison frogs, Dendrobates leucomelas and Epipedobates tricolor, to test the hypothesis that male calling performance is an honest indicator of parental quality. Our analyses are based on data from behavioral observations of mating activities of captive-reared individuals (and their offspring) that were housed in terraria for four consecutive breeding seasons. Male mating success increased with male calling rate and chirp duration in both species, suggesting that females preferred males with more elaborate calls. Because calling performance improved with age in D. leucomelas, female poison frogs that prefer males with more elaborate calls in the wild may end up mating with older males that have already proven their ability to survive. Females that mated with good callers obtained higher quality offspring. Eggs fertilized by males with high calling rates and long chirp durations had higher hatching success and produced tadpoles that were more likely to metamorphose into surviving frogs. As a consequence, females that mated with males with high calling performance obtained more surviving offspring per egg, compared to females that mated with poor callers. Collectively, our findings comply with the notion that female poison frogs prefer to mate with good callers because calling performance is a reliable predictor of offspring quality. The possible influence of maternal allocation and reasons for the strong effect size compared to previous studies are discussed. 相似文献
24.
This study investigates how rising obesity has affected eligibility to serve in the United States Public Health Service Commissioned Corps (PHSCC), the uniformed service charged with protecting and promoting public health in the U.S. Data are drawn from the National Health and Nutrition Examination Surveys. Between 1959 and 2010, the percentage of eligible civilians who exceed the weight-for-height and body fat standards of the PHSCC rose from 9.05% to 18.24% among men, and from 6.13% to 23.10% among women. Simulations indicate that a further 1% increase in population body weight will result in an additional 3.42% of men and 5.08% of women exceeding PHSCC accession standards.This study documents an under appreciated consequence of the rise in obesity: fewer Americans eligible to develop and implement a public health response to obesity through the PHSCC. This illustrates how a public health problem can undermine the public health labor force, compromising a response and risking a self-reinforcing trend. These findings are timely as the Patient Protection and Affordable Care Act (ACA) calls for a major expansion of the PHSCC. 相似文献
25.
When monocytes isolated from human blood adhere to glass substratum, actin- and vinculin-containing punctate plaques rapidly appear at the ventral surface of the cells. We show here that highly purified human leukocyte interferon (IFN) can inhibit formation of these adhesion plaques in a dose-dependent manner. Complete inhibition was obtained when 300 IU/ml IFN were added into the cell-seeding medium. Plaques already formed in the absence of IFN were only partially affected by subsequent addition of IFN into the culture medium. Prevention by IFN of the formation of the adhesion plaques was associated with loosened attachment of the cells to the substratum. Effect of IFN on cellular morphology was complex. At higher doses, IFN added to the cultures within 24 h of seeding almost completely inhibited the differentiation of monocytes to macrophages and most of the cells remained rounded. At lower doses, however, an enhancement of the bipolar spreading was seen and the end result was a culture with predominantly elongated fibroblastoid cells. The latter cells, unlike the fibroblastoid cells in untreated monocyte-macrophage cultures, were completely devoid of the actin plaques, while the reorganization of vimentin-type intermediate filaments took place in a normal manner. These results further support the view that the actin- and vinculin-containing plaques have a role in mediating firm adherence of human monocytes to growth substratum. 相似文献
26.
Martin A. Nowak Corina E. Tarnita Tibor Antal 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1537):19-30
Evolutionary dynamics shape the living world around us. At the centre of every evolutionary process is a population of reproducing individuals. The structure of that population affects evolutionary dynamics. The individuals can be molecules, cells, viruses, multicellular organisms or humans. Whenever the fitness of individuals depends on the relative abundance of phenotypes in the population, we are in the realm of evolutionary game theory. Evolutionary game theory is a general approach that can describe the competition of species in an ecosystem, the interaction between hosts and parasites, between viruses and cells, and also the spread of ideas and behaviours in the human population. In this perspective, we review the recent advances in evolutionary game dynamics with a particular emphasis on stochastic approaches in finite sized and structured populations. We give simple, fundamental laws that determine how natural selection chooses between competing strategies. We study the well-mixed population, evolutionary graph theory, games in phenotype space and evolutionary set theory. We apply these results to the evolution of cooperation. The mechanism that leads to the evolution of cooperation in these settings could be called ‘spatial selection’: cooperators prevail against defectors by clustering in physical or other spaces. 相似文献
27.
我国转基因技术风险交流分析 总被引:3,自引:0,他引:3
随着生物技术的迅猛发展,发展转基因产业的战略选择与公众对转基因安全疑虑的矛盾十分突出。通过转基因舆情分析,指出我国转基因风险交流存在的不足主要为风险交流工作缺乏顶层设计,信息公开程度较低,风险交流方式和内容单调,公益机构未能发挥应有作用。在此基础上,提出了加强转基因风险交流的政策建议:(1)明确转基因风险交流的目标;(2)建立转基因风险交流协调框架;(3)建立转基因信息公开平台和信息监测平台;(4)完善管理部门和公益机构的风险交流职能;(5)改革科技项目政策。 相似文献
28.
The assessment of sustainability of public services is an important issue, especially at local level, taken into account the central role of local governments as a major public employer and provider of a diversity of services. Local governments are close to citizens and are moving faster than other public sector levels with regard to the integration of sustainability principles in their operations and strategies. A sustainability label to communicate public service performance enables to disclose information directly to service users. However, there is a dearth of research about labels addressing specific sustainability criteria for local services. The main aim of this research was the development of a conceptual framework to define a sustainability label, as a tool to assess and communicate sustainability of local public services. The approach was developed taking into account criteria of the European Union Ecolabel and indicators of the Global Reporting Initiative guidelines. The ecolabel is a relatively well-known voluntary instrument in Europe and has the potential for application in public service activities and operations, but only assess the environmental component of sustainability. The Global Reporting Initiative, in particular the Sector Supplement for Public Agencies, was then used to integrate the other sustainability components. Thirty-six (36) criteria and respective indicators were adapted for the proposed sustainability label conceptual framework. A Portuguese local public service was used as an exploratory case study to test the proposed conceptual model into practice. The overall results demonstrate that few criteria were accomplished in this local public service, stressing that new practices and public policies need to be adopted to invert the current trend, especially through the application of assessment systems. This exploratory case study research has shown how useful can be a sustainability label to support local governments in evaluating and communicating the sustainability performance of their public services. This case could drive and support other government levels, including central and regional public administration, in adopting and exploring public service labels and their associated performance approaches. 相似文献
29.
David B. Resnik 《Developing world bioethics》2018,18(2):135-143
Effective community engagement is an important legal, ethical, and practical prerequisite for conducting field trials of genetically modified mosquitoes, because these studies can substantially impact communities and it is usually not possible to obtain informed consent from each community member. Researchers who are planning to conduct field trials should develop a robust community engagement strategy that meets widely recognized standards for seeking approval from the affected population, such as timeliness, consent, information sharing, transparency, understanding, responsiveness, mutual understanding, inclusiveness, and respectfulness. Additional research is needed on the effectiveness of different methods of engaging communities in field trials of genetically modified mosquitoes and how to respond to public opposition to genetically modified organisms. For research programs involving the genetic modification of disease vectors to move forward, they must have public acceptance and support, which cannot be achieved without effective community engagement. 相似文献
30.
Bruce Knauft 《The Australian journal of anthropology》2019,30(1):3-17
‘Dark Anthropology’ and its complementary ‘Anthropology of the Good’ have become influential and debated notions in anthropology in recent years. I here parse distinctive features of these emphases, address their relation to theory and to ethnography, and consider the stakes involved in concretely applying their conceptual designations. I discuss the general shift in anthropology from grand theory to key concept, and the topical delimitation of theory that results. In larger purview, Dark Anthropology and the Anthropology of the Good both have long theoretical genealogies as well as practical contexts of political and social understanding, including vis‐à‐vis recent events in the U.S. and elsewhere. I suggest that considering the relationship between politico‐economically structured inequality and attempts to assert positive meaning and purpose is the most productive way to ethnographically apply their alternative conceptualisations. This brings to greater focus the thorny question of whose understanding of inequality or suffering, or of moral value and positive wellbeing, is being articulated—the sentiments of the people studied, or the concepts of the analyst? It seems vital to examine both analytic and indigenous views of dark times, and of the good, to refine our understanding of both, that is, in order to consider our complementary conceptualisations in relation to both sides of the emic/etic coin. This refines our understanding of local sensibilities and also of the appropriate limit points of our own conceptual associations. 相似文献