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31.
Novel stimuli often require a rapid reallocation of sensory processing resources to determine the significance of the event, and the appropriate behavioral response. Both the amygdala and the visual cortex are central elements of the neural circuitry responding to novelty, demonstrating increased activity to new as compared to highly familiarized stimuli. Further, these brain areas are intimately connected, and thus the amygdala may be a key region for directing sensory processing resources to novel events. Although knowledge regarding the neurocircuit of novelty detection is gradually increasing, we still lack a basic understanding of the conditions that are necessary and sufficient for novelty-specific responses in human amygdala and the visual cortices, and if these brain areas interact during detection of novelty. In the present study, we investigated the response of amygdala and the visual cortex to novelty, by comparing functional MRI activity between 1st and 2nd time presentation of a series of emotional faces in an event-related task. We observed a significant decrease in amygdala and visual cortex activity already after a single stimulus exposure. Interestingly, this decrease in responsiveness was less for subjects with a high score on state anxiety. Further, novel faces stimuli were associated with a relative increase in the functional coupling between the amygdala and the inferior occipital gyrus (BA 18). Thus, we suggest that amygdala is involved in fast sensory boosting that may be important for attention reallocation to novel events, and that the strength of this response depends on individual state anxiety.  相似文献   
32.
Neurotransmitter transporters play an important role in termination of synaptic transmission by mediating reuptake of neurotransmitter, but the molecular processes behind translocation are still unclear. The crystal structures of the bacterial homologue, LeuT, provided valuable insight into the structural and dynamic requirements for substrate transport. These structures support the existence of gating domains controlling access to a central binding site. On the extracellular side, access is controlled by the “thin gate” formed by an interaction between Arg-30 and Asp-404. In the human dopamine transporter (DAT), the corresponding residues are Arg-85 and Asp-476. Here, we present results supporting the existence of a similar interaction in DAT. The DAT R85D mutant has a complete loss of function, but the additional insertion of an arginine in opposite position (R85D/D476R), causing a charge reversal, results in a rescue of binding sites for the cocaine analogue [3H]CFT. Also, the coordination of Zn2+ between introduced histidines (R85H/D476H) caused a ∼2.5-fold increase in [3H]CFT binding (Bmax). Importantly, Zn2+ also inhibited [3H]dopamine transport in R85H/D476H, suggesting that a dynamic interaction is required for the transport process. Furthermore, cysteine-reactive chemistry shows that mutation of the gating residues causes a higher proportion of transporters to reside in the outward facing conformation. Finally, we show that charge reversal of the corresponding residues (R104E/E493R) in the serotonin transporter also rescues [3H](S)-citalopram binding, suggesting a conserved feature. Taken together, these data suggest that the extracellular thin gate is present in monoamine transporters and that a dynamic interaction is required for substrate transport.  相似文献   
33.
34.
Human-carnivore conflicts are complex and are influenced by: the spatial distribution of the conflict species; the organisation and intensity of management measures such as zoning; historical experience with wildlife; land use patterns; and local cultural traditions. We have used a geographically stratified sampling of social values and attitudes to provide a novel perspective to the human – wildlife conflict. We have focused on acceptance by and disagreements between residents (measured as Potential Conflict Index; PCI) towards illegal hunting of four species of large carnivores (bear, lynx, wolf, wolverine). The study is based on surveys of residents in every municipality in Sweden and Norway who were asked their opinion on illegal hunting. Our results show how certain social values are associated with acceptance of poaching, and how these values differ geographically independent of carnivore abundance. Our approach differs from traditional survey designs, which are often biased towards urban areas. Although these traditional designs intend to be representative of a region (i.e. a random sample from a country), they tend to receive relatively few respondents from rural areas that experience the majority of conflict with carnivores. Acceptance of poaching differed significantly between Norway (12.7–15.7% of respondents) and Sweden (3.3–4.1% of respondents). We found the highest acceptance of illegal hunting in rural areas with free-ranging sheep and strong hunting traditions. Disagreements between residents (as measured by PCI) were highest in areas with intermediate population density. There was no correlation between carnivore density and either acceptance of illegal hunting or PCI. A strong positive correlation between acceptance of illegal hunting and PCI showed that areas with high acceptance of illegal hunting are areas with high potential conflict between people. Our results show that spatially-stratified surveys are required to reveal the large scale patterns in social dynamics of human-wildlife conflicts.  相似文献   
35.
The effect of patch isolation on reproductive synchrony in the root vole   总被引:1,自引:0,他引:1  
Both social and environmental cues can synchronise breeding, but are likely to operate at different spatial and temporal scales. Here we test if breeding is synchronised at the patch or the population level in experimental patchy populations of root voles. We found no overall synchronisation neither at the patch nor at the population level. However, at the patch level, breeding was synchronised within patches if the patches were isolated and thus had little exchange of animals with other patches. In accordance with what has been predicted for matrilineally structured populations, we conclude that breeding synchrony is facilitated when social cues are exchanged within stable female groups.  相似文献   
36.
Four-day-old and newly excysted H. diminuta were exposed in vitro (37 degrees C; 5% CO2/air atmosphere) to serum and peritoneal cells (1.7-4.4 X 10(5] obtained from rats. Four-day-old worms incubated in serum alone were lysed in titres of less than 16. In assays containing peritoneal cells, leucocytes, predominantly eosinophils and macrophages, adhered to the posterior end of the parasite in serum titre 32, but not in serum titres 64 and 128. In this region of the worms phagocytosis of microtriches by macrophages, microthrix denudation and loss of tegument were noted. Serum-mediated lysis of newly excysted cysticercoids occurred at a serum titre of 64 and leucocyte adherence and phagocytosis of microtriches occurred in serum titres 128 and 256. Attachment of peritoneal cells to worms did not occur in assays containing heat-inactivated serum and it is suggested that regional leucocyte adherence and subsequent parasite damage is complement-mediated.  相似文献   
37.
Understanding foraging decisions made by wildlife at different spatio‐temporal scales is important for wildlife management and conservation. We tested whether foraging decisions by Masai giraffe (Giraffa camelopardalis tippelskirchi Matschie) differed with scales; habitat, patch and tree in a heterogeneous savannah. We collected data from Arusha National Park, Tanzania, in March–May and August–October 2013. Visual observations were used to collect data on foraging behaviour. Measurements of tree height and stem height and scoring of accumulated browsing were made in 133 patches around trees where the giraffes had been seen browsing, and in a corresponding number of available patches. Giraffes selected Acacia shrub and Dodonea shrub habitats but not for water availability or predator avoidance. For patch use, giraffe selected high quantity of Acacia xanthophloea and Dodonea viscosa. Between plant species, A. xanthophloea was the most preferred and within plant species, tree quality was enhanced by tree height and high score of accumulated browsing. Generally, giraffes selected for A. xanthophloea at all scales.  相似文献   
38.

Background

Previous research indicates that people with osteoarthritis (OA) are not receiving the recommended and optimal treatment. Based on international treatment recommendations for hip and knee OA and previous research, the SAMBA model for integrated OA care in Norwegian primary health care has been developed. The model includes physiotherapist (PT) led patient OA education sessions and an exercise programme lasting 8–12 weeks. This study aims to assess the effectiveness, feasibility, and costs of a tailored strategy to implement the SAMBA model.

Methods/design

A cluster randomized controlled trial with stepped wedge design including an effect, process, and cost evaluation will be conducted in six municipalities (clusters) in Norway. The municipalities will be randomized for time of crossover from current usual care to the implementation of the SAMBA model by a tailored strategy. The tailored strategy includes interactive workshops for general practitioners (GPs) and PTs in primary care covering the SAMBA model for integrated OA care, educational material, educational outreach visits, feedback, and reminder material. Outcomes will be measured at the patient, GP, and PT levels using self-report, semi-structured interviews, and register based data. The primary outcome measure is patient-reported quality of care (OsteoArthritis Quality Indicator questionnaire) at 6-month follow-up. Secondary outcomes include referrals to PT, imaging, and referrals to the orthopaedic surgeon as well as participants’ treatment satisfaction, symptoms, physical activity level, body weight, and self-reported and measured lower limb function. The actual exposure to the tailor made implementation strategy and user experiences will be measured in a process evaluation. In the economic evaluation, the difference in costs of usual OA care and the SAMBA model for integrated OA care will be compared with the difference in health outcomes and reported by the incremental cost-effectiveness ratio (ICER).

Discussion

The results from the present study will add to the current knowledge on tailored strategies, which aims to improve the uptake of evidence-based OA care recommendations and improve the quality of OA care in primary health care. The new knowledge can be used in national and international initiatives designed to improve the quality of OA care.

Trial registration

ClinicalTrials.gov NCT02333656
  相似文献   
39.
We present the results from a radiotelemetric study on space use and activity in a natural population of the wood lemming Myopus schisticolor. Male home ranges were larger than females, and the ratio female home range to male home range was smaller than expected compared to other small rodents. Males moved distances 4-12 times longer than females. We argue that this difference in mobility gives a higher probability of capturing males than females in snap trap studies. If there is a sex biased trappability, this might explain the increasing female biased sex ratio during the snow free season (1:1 in spring, 3:1 [female:male| in autumn), as a higher mortality of males during the reproductive season.  相似文献   
40.
The biomass of 8-day-old worms of Hymenolepis diminuta in secondary infections, administered to rats 3-10 days after chemotherapeutically expelling a primary infection, was 70-90% less, and the worms were more posteriorly distributed, than in naive controls. The strong depressive effect on growth waned rapidly over 2-5 weeks, but even in rats not challenged until 17 months later, worm growth was weakly depressed by 30%. The extent to which growth was depressed in a secondary infection was independent of the number of worms in the challenge but increased with number of worms in the immunizing infection up to four to eight worms. Further increase up to 64 worms had little effect. This suggests, as it is known that the biomass of worms in a rat reaches a maximum with infections of between five and 10 worms, that the change in the intestine is proportional to biomass, not number, of worms. It is argued that partially suppressed immuno-inflammatory changes in the intestine, which will affect secondary worms so strongly, will also have depressed growth and fecundity effects on the primary worms, that a dynamic equilibrium is reached between the strength of the intestinal response and the biomass of the tapeworm, and that it is reaching this equilibrium, not a 'crowding effect', which limits H. diminuta to a level compatible with the survival of the rat.  相似文献   
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