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931.
Lynn K. Nyhart 《Theorie in den Biowissenschaften》2003,122(2-3):162-173
Summary The school Carl Gegenbaur cultivated at Heidelberg (1873–1901) was critical to the history of German morphology in multiple
ways. During and after his lifetime, the school carried out detailed comparative anatomical and embryological investigations
in an evolutionary framework, thereby contributing substantially to the project of vertebrate evolutionary morphology. Its
members also defended their mentor when his ideas came under attack. After his death, they labored to perpetuate his program
and his memory in the increasingly unwelcoming environment of medical education and research. While the senior members of
the school did this largely through institutional means-seeking to place Gegenbaur sympathizers in academic and editorial
positions-its junior members absorbed some of the criticisms of the school to develop a modified, more functional approach
to evolutionary morphology. The school thus kept the Gegenbaur program alive and active in the German-speaking lands for over
fifty years.
This paper is drawn largely from Nyhart (1995), esp. chapter 7 (supported by NSF award no. 8910873). Information not otherwise
documented derives from this book. 相似文献
932.
933.
Reinterpreting Responsiveness for Health Systems Research in Low and Middle‐Income Countries
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The ethical concept of responsiveness has largely been interpreted in the context of international clinical research. In light of the increasing conduct of externally funded health systems research (HSR) in low‐ and middle‐income countries (LMICs), this article examines how responsiveness might be understood for such research and how it can be applied. It contends that four features (amongst others) set HSR in LMICs apart from international clinical research: a focus on systems; being context‐driven; being policy‐driven; and being closely linked to development objectives. These features support reinterpreting responsiveness for HSR in LMICs as responsiveness to systems needs, where health system performance assessments can be relied upon to identify systems needs, and/or responsiveness to systems priorities, which entails aligning research with HSR priorities set through country‐owned processes involving national and sub‐national policymakers from host countries. Both concepts may be difficult to achieve in practice. Country ownership is not an established fact for many countries and alignment to their priorities may be meaningless without it. It is argued that more work is, therefore, needed to identify strategies for how the responsiveness requirement can be ethically fulfilled for HSR in LMICs under non‐ideal conditions such as where host countries have not set HSR priorities via country‐owned processes. Embeddedness is proposed as one approach that could be the focus of further development. 相似文献
934.
To determine when the life of a human organism begins, Mark T. Brown has developed the somatic integration definition of life. Derived from diagnostic criteria for human death, Brown’s account requires the presence of a life-regulation internal control system for an entity to be considered a living organism. According to Brown, the earliest point at which a developing human could satisfy this requirement is at the beginning of the fetal stage, and so the embryo is not regarded as a living human organism. This, Brown claims, has significant bioethical implications for both abortion and embryo experimentation. Here, we dispute the cogency of Brown’s derivation. Diagnostic criteria for death are used to determine when an organism irreversibly ceases functioning as an integrated whole, and may vary significantly depending on how developed the organism is. Brown’s definition is derived from a specific definition of death applicable to postnatal human beings, which is insufficient for generating a general definition for human organismal life. We have also examined the bioethical implications of Brown’s view, and have concluded that they are not as significant as he believes. Whether the embryo is classified as a human organism is of peripheral interest—a far more morally relevant question is whether the embryo is a biological individual with an identity that is capable of persisting during development. 相似文献
935.
RICHARD A. ERICKSON 《The Journal of wildlife management》2008,72(2):575-579
ABSTRACT Student Chapters of The Wildlife Society serve the parent organization as a source of new members while promoting professional development among aspiring wildlife biologists. However, little is known about the operation of the Student Chapters across North America. I conducted an online survey between March and May 2006 to learn about variation among chapters and to define successful chapters with a quantifiable, objective parameter (e.g., the active members or budgets). I sent chapter advisors and student officers the online survey via e-mail. Of 92 Student Chapters known to the parent Society in 2005, 66 active and one inactive chapters responded. Activities, sizes, and budgets varied greatly among chapters. Additionally, perceived values of membership by survey participants matched the parent Society's goals. No clear definition of a successful chapter (e.g., those with the most money or members) emerged, but chapters faced some evident problems including apathy from students and advisors as well as a lack of support from the parent Society. Based upon the survey, I recommend Student Chapters have strong projects and activities as well as consider collaborating with other professional organizations. I recommend the parent Society continue to expand student programs and incorporate students into the Society. 相似文献
936.
Auguste Dargent Jean-Paul Pais de Barros Samir Saheb Randa Bittar Wilfried Le Goff Alain Carri Thomas Gautier Isabelle Fournel Anne Laure Rerole Hlne Choubley David Masson Laurent Lagrost Jean-Pierre Quenot 《Journal of lipid research》2020,61(12):1776
Lipopolysaccharide (LPS) is a key player for innate immunity activation. It is therefore a prime target for sepsis treatment, as antibiotics are not sufficient to improve outcome during septic shock. An extracorporeal removal method by polymyxin (PMX) B direct hemoperfusion (PMX-DHP) is used in Japan, but recent trials failed to show a significant lowering of circulating LPS levels after PMX-DHP therapy. PMX-DHP has a direct effect on LPS molecules. However, LPS is not present in a free form in the circulation, as it is mainly carried by lipoproteins, including LDLs. Lipoproteins are critical for physiological LPS clearance, as LPSs are carried by LDLs to the liver for elimination. We hypothesized that LDL apheresis could be an alternate method for LPS removal. First, we demonstrated in vitro that LDL apheresis microbeads are almost as efficient as PMX beads to reduce LPS concentration in LPS-spiked human plasma, whereas it is not active in PBS. We found that PMX was also adsorbing lipoproteins, although less specifically. Then, we found that endogenous LPS of patients treated by LDL apheresis for familial hypercholesterolemia is also removed during their LDL apheresis sessions, with both electrostatic-based devices and filtration devices. Finally, LPS circulating in the plasma of septic shock and severe sepsis patients with gram-negative bacteremia was also removed in vitro by LDL adsorption. Overall, these results underline the importance of lipoproteins for LPS clearance, making them a prime target to study and treat endotoxemia-related conditions. 相似文献
937.
The experiences of pregnant women in an interventional clinical trial: Research In Pregnancy Ethics (RIPE) study
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Angela Ballantyne Susan Pullon Lindsay Macdonald Christine Barthow Kristen Wickens Julian Crane 《Bioethics》2017,31(6):476-483
There is increasing global pressure to ensure that pregnant women are responsibly and safely included in clinical research in order to improve the evidence base that underpins healthcare delivery during pregnancy. One supposed barrier to inclusion is the assumption that pregnant women will be reluctant to participate in research. There is however very little empirical research investigating the views of pregnant women. Their perspective on the benefits, burdens and risks of research is a crucial component to ensuring effective recruitment. The Research In Pregnancy Ethics (RIPE) study set out to ascertain the views of pregnant women about research participation using an inductive thematic analysis. We conducted semi‐structured interviews with 20 women who had participated in a double‐blind randomised placebo controlled trial in Wellington (New Zealand) while pregnant. Our results show that at least some pregnant women recognise the value and importance of research during pregnancy. The women we interviewed were deeply invested in the research process and outcomes. Key motivations for participating were altruism, playing a valuable civic role and the importance of research. The main perceived burdens related to inconvenience and time commitment. For some women, possible randomization to the placebo arm was regarded as a burden or disadvantage. 相似文献
938.
Recent studies indicate poor understanding of the causes and consequences of climate change among college students. In an effort to improve climate change literacy, we have developed an authentic research experience for upper level undergraduate students focused on resolving spatial and temporal patterns of coral reef bleaching, an ecologically and economically important consequence of climate warming. In the research, students use a public archive of maps generated by the United States National Oceanographic and Atmospheric Association (NOAA) that use coloration to depict ocean areas experiencing above-average surface temperatures and where corals are at an increased risk of bleaching. Students are required to quantify the total area of coloration on individual maps using open-source image analysis software called Image J. By quantifying coloration (ie bleaching risk) over a large number of maps in a chronological sequence, students can test hypotheses regarding the relationship between ongoing climate warming and coral bleaching risk. Students are required to summarise their findings in a scientific journal-style report that incorporates graphical representations and statistical tests of their coral bleaching risk data. The research activity is cost-effective, repeatable, requires little specialised knowledge and addresses common programmatic learning outcomes that target scientific communication, quantitative reasoning and sustainability. 相似文献
939.
Per Milberg 《应用植被学》2014,17(3):604-608
The effect of applied vegetation science on society has the potential to increase by adopting an evidence‐based approach. However, this would require a shift in focus towards effect size and results suitable for meta‐analyses, a focus on practitioners as potential readers, more emphasis on practical problems rather than mechanism, and an acceptance of all well‐executed experimental studies, even if confirmatory. Thus, the prevailing editorial policies need to be reconsidered, as well as the methods of analysing, reporting and evaluating research, for our research efforts to be of better use within society. 相似文献
940.
Entomologist Jonathan Majer is a world pioneer in using ants as indicators of restoration success. With hundreds of published works to his name (and five species of ants named after him), he reflects in this interview on his undimming passion for learning and teaching about invertebrates – a group of animals that can include up to 95% of faunal species in a reference community. 相似文献