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961.
The role of Th17 cells in cancer patients remains unclear and controversial. In this study, we have analyzed the phenotype of in vitro primed Th17 cells and further characterized their function on the basis of CCR4 and CCR6 expression. We show a novel function for a subset of IL-17-secreting CD4(+) T cells, namely, CCR4(+)CCR6(+)Th17 cells. When cultured together, CCR4(+)CCR6(+)Th17 cells suppressed the lytic function, proliferation, and cytokine secretion of both Ag-specific and CD3/CD28/CD2-stimulated autologous CD8(+) T cells. In contrast, CCR4(-)CCR6(+) CD4(+) T cells, which also secrete IL-17, did not affect the CD8(+) T cells. Suppression of CD8(+) T cells by CCR4(+)CCR6(+)Th17 cells was partially dependent on TGF-β, because neutralization of TGF-β in cocultures reversed their suppressor function. In addition, we also found an increase in the frequency of CCR4(+)CCR6(+), but not CCR4(-)CCR6(+) Th17 cells in peripheral blood of hepatocellular carcinoma patients. Our study not only underlies the importance of analysis of subsets within Th17 cells to understand their function, but also suggests Th17 cells as yet another immune evasion mechanism in hepatocellular carcinoma. This has important implications when studying the mechanisms of carcinogenesis, as well as designing effective immunotherapy protocols for patients with cancer.  相似文献   
962.
Recently, it has been demonstrated that disease progression during HIV infection is not determined merely by the number of HIV-specific T cells but also by their quality (J. R. Almeida, et al., J. Exp. Med. 204:2473-2485, 2007; C. T. Berger, et al., J. Virol. 85:9334-9345, 2011; M. R. Betts, et al., Blood 107:4781-4789, 2006; V. V. Ganusov, et al., J. Virol. 85:10518-10528, 2011; P. Kiepiela, et al., Nat. Med. 13:46-53, 2007; and F. Pereyra, et al., J. Infect. Dis. 197:563-571, 2008). Therefore, strategies to specifically enhance or induce high-quality, HIV-specific T-cell responses are necessary to develop effective immune therapies. Thalidomide, lenalidomide, and pomalidomide have a strong capacity to boost immune responses and are therefore referred to as immunomodulatory drugs (IMiDs). We evaluated the effects of lenalidomide and pomalidomide on HIV-specific T cells. We found that the presence of IMiDs during in vitro T-cell stimulation with dendritic cells electroporated with Gag- or Nef-encoding mRNA resulted in higher numbers of cytokine-secreting HIV-specific CD8(+) T cells, particularly inducing polyfunctional HIV-specific CD8(+) T cells with an enhanced lytic capacity. Furthermore, CD8(+) T-cell responses were detected upon stimulation with lower antigenic peptide concentrations, and a higher number of Gag epitopes was recognized upon addition of IMiDs. Finally, IMiDs reduced the proliferation of the HIV-specific CD4(+) T cells while increasing the number of polyfunctional CD4(+) T cells. These results provide new information about the effects of IMiDs on antigen-specific T cells and suggest that these drugs increase the efficacy of immune therapies for infectious diseases and cancer.  相似文献   
963.
This paper investigates fault diagnosis in batch processes and presents a comparative study of feature extraction and classification techniques applied to a specific biotechnological case study: the fermentation process model by Birol et al. (Comput Chem Eng 26:1553–1565, 2002), which is a benchmark for advanced batch processes monitoring, diagnosis and control. Fault diagnosis is achieved using four approaches on four different process scenarios based on the different levels of noise so as to evaluate their effects on the performance. Each approach combines a feature extraction method, either multi-way principal component analysis (MPCA) or multi-way independent component analysis (MICA), with a classification method, either artificial neural network (ANN) or support vector machines (SVM). The performance obtained by the different approaches is assessed and discussed for a set of simulated faults under different scenarios. One of the faults (a loss in mixing power) could not be detected due to the minimal effect of mixing on the simulated data. The remaining faults could be easily diagnosed and the subsequent discussion provides practical insight into the selection and use of the available techniques to specific applications. Irrespective of the classification algorithm, MPCA renders better results than MICA, hence the diagnosis performance proves to be more sensitive to the selection of the feature extraction technique.  相似文献   
964.
A change in land use from agriculture to forest generally increases soil acidity. However, it remains unclear to what extent plant traits can enhance or mitigate soil acidification caused by atmospheric deposition. Soil acidification is detrimental for the survival of many species. An in‐depth understanding of tree species‐specific effects on soil acidification is therefore crucial, particularly in view of the predicted global increases in acidifying nitrogen (N) deposition. Here, we report soil acidification rates in a chronosequence of broadleaved deciduous forests planted on former arable land in Belgium. This region receives one of the highest loads of potentially acidifying atmospheric deposition in Europe, which allowed us to study a ‘worst case scenario’. We show that less than four decades of forest development caused significant soil acidification. Atmospheric deposition undoubtedly and unequivocally drives postagricultural forests towards more acidic conditions, but the rate of soil acidification is also determined by the tree species‐specific leaf litter quality and litter decomposition rates. We propose that the intrinsic differences in leaf litter quality among tree species create fundamentally different nutrient cycles within the ecosystem, both directly through the chemical composition of the litter and indirectly through its effects on the size and composition of earthworm communities. Poor leaf litter quality contributes to the absence of a burrowing earthworm community, which retards leaf litter decomposition and, consequently, results in forest‐floor build‐up and soil acidification. Also nutrient uptake and N2 fixation are causing soil acidification, but were found to be less important. Our results highlight the fact that tree species‐specific traits significantly influence the magnitude of human pollution‐induced soil acidification.  相似文献   
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966.
967.
Various stakeholders in science have put research integrity high on their agenda. Among them, research funders are prominently placed to foster research integrity by requiring that the organizations and individual researchers they support make an explicit commitment to research integrity. Moreover, funders need to adopt appropriate research integrity practices themselves. To facilitate this, we recommend that funders develop and implement a Research Integrity Promotion Plan (RIPP). This Consensus View offers a range of examples of how funders are already promoting research integrity, distills 6 core topics that funders should cover in a RIPP, and provides guidelines on how to develop and implement a RIPP. We believe that the 6 core topics we put forward will guide funders towards strengthening research integrity policy in their organization and guide the researchers and research organizations they fund.

Research funders are prominently placed to foster research integrity by requiring that researchers make an explicit commitment to research integrity. This Consensus View suggests 6 core topics that funders should cover in a research integrity promotion plan and provides practical recommendations for how to implement one.

To improve research quality and validity, foster responsible research cultures, and maintain public trust in science, various stakeholders have put research integrity high on their agenda. Among them, research funders are increasingly acknowledging their pivotal role in contributing to a culture of research integrity. For example, the European Commission (EC) is mandating research organizations receiving funding from the €95 billion Horizon Europe program to have, at the institutional level, policies and processes in place for research integrity covering the promotion of good practice, prevention of misconduct and questionable practices, and procedures to deal with breaches of research integrity [1]. To meet these obligations, the EC requires beneficiaries to respect the principles of research integrity as set out in the European Code of Conduct for Research Integrity (ECoC) and suggests that research organizations develop and implement a Research Integrity Promotion Plan (RIPP) [2]. In this Consensus View, we have adopted the World Conference on Research Integrity’s approach to research integrity, by having “research integrity” refer to “the principles and standards that have the purpose to ensure validity and trustworthiness of research” [3]. More specifically, we mostly adhere to the principles outlined in the ECoC: reliability, honesty, respect, and accountability. While many definitions of research integrity exist [4,5], for example, those that distinguish between the integrity of a researcher, integrity of research, and integrity of the research record, the ECoC combines these approaches in a balanced way [1].We believe that funders are prominently placed to foster a culture of research integrity by requiring that the organizations and individual researchers they support make an explicit commitment to research integrity. At the same time, funders need to adopt appropriate research integrity practices themselves. Of late, attention to research integrity among funders has gathered pace, as reflected in several initiatives around the globe that demonstrate how funders can support a culture of research integrity. For example, the US National Science Foundation (NSF) [6] requires applicants’ research organizations to provide training and oversight in the responsible conduct of research, designate individuals responsible for research integrity, and have an institutional certification to testify of its commitment. Also, in 2016, 3 Canadian federal funders joined forces to support research integrity in the Canadian Tri-Agency Framework: Responsible Conduct of Research–Harmony and Responsibility [7]. The framework was subsequently updated in 2021. This framework sets out responsible practices that research organizations and researchers should follow, including rigor, record keeping, accurate referencing, responsible authorship, and the management of conflicts of interest. It also acknowledges the responsibilities of the funders, including “helping to promote the responsible conduct of research and to assist individuals and institutions with the interpretation or implementation of this Responsible Conduct of Research (RCR) Framework”.It is not only major funding organizations in highly developed research environments that are taking steps. Smaller funders are also acting to mandate compliance with research integrity standards. The constantly growing literature on the topic is another sign of development within this area [2,3]. In the USA, research integrity recently reached the political arena, when, following a call from researchers [8], President Biden’s administration published a memorandum on restoring trust [9] that highlights the importance of integrity in research. The memorandum will be supported by the reintroduction of the Scientific Integrity Act. This act will prohibit research misconduct and the manipulation of research findings. It talks of a “culture of research integrity” and demands that funding agencies adopt and enforce research integrity policies, appoint a research integrity officer, and provide regular research integrity and ethics training. The US are not alone in their endeavors. Governments in other countries are equally gearing up to support the integrity and reproducibility of research [10]. However, so far, there is only limited evidence about the effectiveness of such initiatives, although it is generally accepted that they raise awareness among various stakeholders concerning research integrity challenges, strengthen the sense of responsibility of those stakeholders to address those challenges, and thereby ultimately contribute to fostering a culture of research integrity.In a collective effort to foster research integrity, research organizations and funders have their own, complementary roles. The Standard Operating Procedures for Research Integrity (SOPs4RI) consortium has recommended that both research organizations and funders develop a RIPP. A RIPP outlines the key responsibilities of an organization concerning research integrity and details methods and procedures to foster it. For example, in the case of research organizations, a RIPP should facilitate and stimulate a healthy research environment, proper mentoring and supervision, research ethics structures, research integrity training, high-quality dissemination practices, research collaboration, effective data management, and open and fair procedures to deal with breaches of research integrity [11]. Funders have a different role. They can support, safeguard, and incentivise, or even mandate, responsible research practices from research organizations and researchers. Equally important, funders should make sure that their internal processes live up to the highest standards of research integrity. We recognize that funders are many and varied in their scale, portfolio, disciplinary focus, and the extent to which they have procedures and governance arrangements to support research integrity. For all funders, adopting a RIPP will structure and coordinate research integrity practices, giving clarity and transparency to applicant institutions and researchers.In this Consensus View, we highlight examples of best practice of funders worldwide to foster a research integrity culture. With these examples in mind, we suggest guidelines to support funders in taking a leading role in fostering research integrity. In so doing, we acknowledge the local contexts in which funders operate, but we believe that all funders, large and small, in all parts of the world, can and should contribute to improving research validity and building and maintaining trust in science through incentivising and mandating a culture of research integrity. Our core argument is that developing a tailored RIPP will contribute to building an institutional culture of research integrity, both within funding organizations and among the research organizations and individual researchers they fund. Based on empirical work from the SOPs4RI project, we have identified 6 key research integrity topics: researchers’ compliance with research integrity standards; expectations for research organizations; selection of grant applications; declaration of interests; monitoring funded research; and dealing with internal integrity breaches (Fig 1). We recommend that these topics should be included in a RIPP and provide guidelines on developing and implementing a RIPP.Open in a separate windowFig 1Topics to be covered in a RIPP for funders.An overview of the 6 most important topics identified by the SOPs4RI to be included in research funding organization’s RIPP. RIPP, Research Integrity Promotion Plan; SOPs4RI, Standard Operating Procedures for Research Integrity.  相似文献   
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969.
To understand the impact of alternative translation initiation on a proteome, we performed a proteome‐wide study on protein turnover using positional proteomics and ribosome profiling to distinguish between N‐terminal proteoforms of individual genes. By combining pulsed SILAC with N‐terminal COFRADIC, we monitored the stability of 1,941 human N‐terminal proteoforms, including 147 N‐terminal proteoform pairs that originate from alternative translation initiation, alternative splicing or incomplete processing of the initiator methionine. N‐terminally truncated proteoforms were less abundant than canonical proteoforms and often displayed altered stabilities, likely attributed to individual protein characteristics, including intrinsic disorder, but independent of N‐terminal amino acid identity or truncation length. We discovered that the removal of initiator methionine by methionine aminopeptidases reduced the stability of processed proteoforms, while susceptibility for N‐terminal acetylation did not seem to influence protein turnover rates. Taken together, our findings reveal differences in protein stability between N‐terminal proteoforms and point to a role for alternative translation initiation and co‐translational initiator methionine removal, next to alternative splicing, in the overall regulation of proteome homeostasis.  相似文献   
970.
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