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11.
Practicing action research in workplaces is a choice of letting oneself be closely involved in other peoples’ integrity as working men and women. The encounter between the researcher and the social group in the contract organization is the vital and sometimes only instrument for generating new learning and lasting change, thus it is critical for engaged action researchers to continuously be self-reflective on our praxis and appearance in this encounter. Within the action research literature, this encounter is discussed in relatively broad terms emphasizing preferred roles, values and strategies for organizing collaborative learning processes. Relatively little is reported, however, on the unpleasant sides of this interaction between the researcher and the collaborative group. In line with Greenwood and Levin’s (1998) argument for the action researcher as a friendly outsider who confronts in a supportive way, most researchers practicing action research have experienced how difficult it is to be as confronting as it takes if dysfunctional social routines are to be changed. In this article, I report on my own practice from an action research project, where I gradually developed my skills and confidence in acting more confronting as to bring forward new collaborating working routines among metal workers. I discuss three different forms of confrontation to be of critical necessity. By daring to act more confrontational, I also realized that it made me feel better about myself as a professional engaged researcher as I could reveal my true meanings and perspectives to the workers. I conclude by suggesting that in order for an engaged researcher to be able to develop her role as a confronting practitioner it is important to work closely in a team with fellow researchers, as well as to have the personal capacity to be self-reflexive and self-therapeutic.  相似文献   
12.
Womelsdorf T  Fries P  Mitra PP  Desimone R 《Nature》2006,439(7077):733-736
Our capacity to process and respond behaviourally to multiple incoming stimuli is very limited. To optimize the use of this limited capacity, attentional mechanisms give priority to behaviourally relevant stimuli at the expense of irrelevant distractors. In visual areas, attended stimuli induce enhanced responses and an improved synchronization of rhythmic neuronal activity in the gamma frequency band (40-70 Hz). Both effects probably improve the neuronal signalling of attended stimuli within and among brain areas. Attention also results in improved behavioural performance and shortened reaction times. However, it is not known how reaction times are related to either response strength or gamma-band synchronization in visual areas. Here we show that behavioural response times to a stimulus change can be predicted specifically by the degree of gamma-band synchronization among those neurons in monkey visual area V4 that are activated by the behaviourally relevant stimulus. When there are two visual stimuli and monkeys have to detect a change in one stimulus while ignoring the other, their reactions are fastest when the relevant stimulus induces strong gamma-band synchronization before and after the change in stimulus. This enhanced gamma-band synchronization is also followed by shorter neuronal response latencies on the fast trials. Conversely, the monkeys' reactions are slowest when gamma-band synchronization is high in response to the irrelevant distractor. Thus, enhanced neuronal gamma-band synchronization and shortened neuronal response latencies to an attended stimulus seem to have direct effects on visually triggered behaviour, reflecting an early neuronal correlate of efficient visuo-motor integration.  相似文献   
13.
There is concern that variola virus, the aetiological agent of smallpox, may be used as a biological weapon. For this reason several countries are now stockpiling (vaccinia virus-based) smallpox vaccine. Although the preventive use of smallpox vaccination has been well documented, little is known about its efficacy when used after exposure to the virus. Here we compare the effectiveness of (1) post-exposure smallpox vaccination and (2) antiviral treatment with either cidofovir (also called HPMPC or Vistide) or with a related acyclic nucleoside phosphonate analogue (HPMPO-DAPy) after lethal intratracheal infection of cynomolgus monkeys (Macaca fascicularis) with monkeypox virus (MPXV). MPXV causes a disease similar to human smallpox and this animal model can be used to measure differences in the protective efficacies of classical and new-generation candidate smallpox vaccines. We show that initiation of antiviral treatment 24 h after lethal intratracheal MPXV infection, using either of the antiviral agents and applying various systemic treatment regimens, resulted in significantly reduced mortality and reduced numbers of cutaneous monkeypox lesions. In contrast, when monkeys were vaccinated 24 h after MPXV infection, using a standard human dose of a currently recommended smallpox vaccine (Elstree-RIVM), no significant reduction in mortality was observed. When antiviral therapy was terminated 13 days after infection, all surviving animals had virus-specific serum antibodies and antiviral T lymphocytes. These data show that adequate preparedness for a biological threat involving smallpox should include the possibility of treating exposed individuals with antiviral compounds such as cidofovir or other selective anti-poxvirus drugs.  相似文献   
14.
Zusammenfassung Wachstumstimulation von 2,3-Dibromo-4,5-Dihydroxybenzylalkohol (Lanosol) in Konzentrationen von 4×10–5–4×10–6 wurde in axenischen Kulturen der RotalgenGoniotrichum alsidii undPolysiphonia urceolata festgestellt. Während das Disulfatdikaliumsalz nicht toxisch und von niedrigerer Aktivität war, hatte 2×10–4 M Lanosol eine Hemmwirkung aufPolysiphonia.  相似文献   
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16.
The dynamics of chromosome evolution in birds and mammals   总被引:20,自引:0,他引:20  
Comparative mapping, which compares the location of homologous genes in different species, is a powerful tool for studying genome evolution. Comparative maps suggest that rates of chromosomal change in mammals can vary from one to ten rearrangements per million years. On the basis of these rates we would expect 84 to 600 conserved segments in a chicken comparison with human or mouse. Here we build comparative maps between these species and estimate that numbers of conserved segments are in the lower part of this range. We conclude that the organization of the human genome is closer to that of the chicken than the mouse and by adding comparative mapping results from a range of vertebrates, we identify three possible phases of chromosome evolution. The relative stability of genomes such as those of the chicken and human will enable the reconstruction of maps of ancestral vertebrates.  相似文献   
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