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121.
122.
脂质组学在医药研究中的应用   总被引:2,自引:0,他引:2  
脂质组学是对整体脂质进行系统分析的一门新兴学科,通过比较不同生理状态下脂代谢网络的变化,进而识别代谢调控中关键的脂生物标志物,最终揭示脂质在各种生命活动中的作用机制。电喷雾电离-质谱技术是脂质组学领域中最核心的研究手段,目前已能对各种脂质尤其是磷脂进行高分辨率、高灵敏度、高通量的分析。随着质谱技术的进步,脂质组学在疾病脂生物标志物的识别、疾病诊断、药物靶点及先导化合物的发现和药物作用机制的研究等方面已展现出广泛的应用前景。  相似文献   
123.
In genomic research the ideal standard of free, informed, prior and explicit consent is sometimes difficult to apply. This has raised concern that important genomic research will be restricted. Different consent procedures have therefore been proposed. This paper explicitly examines the question how, in genomic research, the principles of solidarity and justice can be used to justify forms of diminished individual control over personal data and bio-samples. After a discussion of the notions of solidarity and justice and how they can be related to health care and genomic research, we examine how and in which situations these notions can form a strong moral basis for demanding certain financial sacrifices. Then we examine when these principles can justify consent procedures which diverge from the ideal standard. Because much genomic research is not expected to lead to immediate (clinical) benefits we also discuss the question of whether we can be obliged to make any sacrifices for future (not yet existing) patients. We conclude with the formulation of a number of conditions that have to be met before autonomy sacrifices can be reasonably demanded in genomic research.  相似文献   
124.
BACKGROUND: The objective of this study was to identify factors motivating women to take part in endometriosis research and to determine if these factors differ for women participating in clinical versus basic science studies. METHODS: A consecutive series of 24 women volunteering for participation in endometriosis-related research were asked to indicate, in their own words, why they chose to volunteer. In addition, the women were asked to rate, on a scale of 0 to 10, sixteen potentially motivating factors. The information was gathered in the form of an anonymous self-administered questionnaire. RESULTS: Strong motivating factors (mean score > 8) included potential benefit to other women's health, improvement to one's own condition, and participation in scientific advancement. Weak motivating factors (mean score < 3) included financial compensation, making one's doctor happy, and use of 'natural' products. No difference was detected between clinical and basic science study participants. CONCLUSION: This study is the first study to specifically investigate the factors that motivate women to take part in endometriosis research. Understanding why women choose to take part in such research is important to the integrity of the informed consent process. The factors most strongly motivating women to participate in endometriosis research related to improving personal or public health; the weakest, to financial compensation and pleasing the doctor.  相似文献   
125.
The direct, highly selective and sensitive real-time imaging of neuro- and biochemical mediators is the only way to clarify precisely the chemistry of the brain and to discover the key molecular targets involved in regulation of brain homeostasis. To realize that, we need: high-speed deep-tissue imaging techniques with high spatial and temporal resolution; and ultra-fast and highly selective molecular sensors, giving a possibility to monitor target molecules directly in their physiological environment; in addition, these molecular sensors have to be comparatively small and permeable for blood-brain barrier, to be applicable in brain studies. The present view accents on the perspectives for development of direct approach for investigation of function/flow coupling phenomenon in the brain, based on the current progress in development of ultra-fast molecular sensors for direct visualization of biochemical mediators (e.g., nitric oxide, Ca ions), and high-speed two-photon/multi-photon deep-tissue imaging.  相似文献   
126.
Economic principles motivating social attention in humans   总被引:1,自引:0,他引:1  
We know little about the processes by which we evaluate the opportunity to look at another person. We propose that behavioural economics provides a powerful approach to understanding this basic aspect of social attention. We hypothesized that the decision process culminating in attention to another person follows the same economic principles that govern choices about rewards such as food, drinks and money. Specifically, such rewards are discounted as a function of time, are tradable for other rewards, and reinforce work. Behavioural and neurobiological evidence suggests that looking at other people can also be described as rewarding, but to what extent these economic principles apply to social orienting remains unknown. Here, we show that the opportunity to view pictures of the opposite sex is discounted by delay to viewing, substitutes for money and reinforces work. The reward value of photos of the opposite sex varied with physical attractiveness and was greater in men, suggesting differential utility of acquiring visual information about the opposite sex in men and women. Together, these results demonstrate that choosing whom to look at follows a general set of economic principles, implicating shared neural mechanisms in both social and non-social decision making.  相似文献   
127.
Rudimentary studies on aspects of biochemistry in India date back to 1927. But, in the field of Immunology, such studies were started by scholars only during early 1970s at the All India Institute of Medical Sciences, New Delhi, India. Science and Technology was not an immediate priority until 1961 due to domestic and political conditions in the country. We were then 11 years old since independence and our focus was on economic and social developments. Gradually, improvements were made in the field and now we have 15 to 20 major groups (small in size) of immunologists in the country, who have made significant contribution in the field during the last 8 to 10 years. Hence, we anticipate improvements in manpower and infrastructure in the near future.  相似文献   
128.
回顾了世界蜉蝣目化石研究简史,列出已发表的化石种类名录、分布及年代,共40科、124属、218种,其中包括中国的8属13种;描述了不同地质时期主要蜉蝣化石的分类单元和分布地区.简要介绍了蜉蝣分类系统及系统发育、稚虫食性、与其它昆虫的关系和古生态等方面的研究成果.在本文的第2部分,初步分析了目前该类群所存在的一些问题,并对今后的研究工作进行了展望.  相似文献   
129.
橘皮中含有丰富的黄酮类化合物,尤其是其中的黄酮和黄酮醇含量虽低,却表现出更强的生物活性。本文就近年来广大研究者对橘皮中黄酮类化合物的种类、生理活性及其制备和开发利用等方面的研究状况作一综述,旨在为发现结构新颖的橘皮黄酮类活性成分及其深度开发利用提供依据。  相似文献   
130.
Questions: 1. Which plant traits and habitat characteristics best explain local above‐ground persistence of vascular plant species and 2. Is there a trade‐off between local above‐ground persistence and the ability for seed dispersal and below‐ground persistence in the soil seed bank? Locations: 845 long‐term permanent plots in terrestrial habitats across the Netherlands. Methods: We analysed the local above‐ground persistence of vascular plants in permanent plots (monitored once a year for ca. 16 year) with respect to functional traits and habitat preferences using survival statistics (Kaplan‐Meier analysis and Cox’ regression). These methods account for censored data and are rarely used in vegetation ecology. Results: Local above‐ground persistence is determined by both functional traits (especially the ability to form long‐lived clonal connections) and habitat preferences (especially nutrient requirements). Above‐ground persistence is negatively related to the ability for dispersal by wind and to the ability to accumulate a long‐term persistent soil seed bank (‘dispersal through time’) and is positively related to the ability for dispersal by water. Conclusions: Most species have a half‐life expectation over 15 years, which may contribute to time lags after changes in habitat quality or ‐configuration (‘extinction debt’). There is evidence for a trade‐off relationship between local above‐ground persistence and below‐ground seed persistence, while the relationship with dispersal in space is vector specific. The rate of species turnover increases with productivity.  相似文献   
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