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121.

Mountain ecosystems are considered to be sensitive to global change and human disturbance. Our retrospective analysis of archival aerial imagery showed dynamics of arctic-alpine tundra vegetation in the Krkono?e Mountains, Czech Republic; image classification revealed a change in land cover classes in 44% of the study area over the past eighty years. This particular ecosystem holds many rare features, such as high numbers of endemic, glacial relict and rare species as well as relict geomorphological components such as sorted patterned ground. Our study revealed an accelerating expansion of the native and planted shrub, Pinus mugo, from 30.6% of the study area in 1936 to 48.6% in 2018, mostly at the expense of grasslands that decreased from 59.3% in 1936 to 44.2% in 2018. Shrub expansion represents a threat to relict periglacial landforms, covering 8% of the sorted patterned ground in 1936 and 26.5% in 2018. Shrub encroachment was shown to be due to artificial planting of the pine in the past as well as the cessation of former farming (mowing and cattle grazing) and, most probably, also by global change. Both dwarf pine stands and tundra grasslands hold high conservation value (Natura 2000 habitats); a balance between different nature protection interests must, therefore, be ensured. Detailed spatio-temporally, explicit outputs of the remote sensing analysis can serve as a baseline for nature conservation in order to prepare corresponding management plans.

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Music has a pervasive tendency to rhythmically engage our body. In contrast, synchronization with speech is rare. Music’s superiority over speech in driving movement probably results from isochrony of musical beats, as opposed to irregular speech stresses. Moreover, the presence of regular patterns of embedded periodicities (i.e., meter) may be critical in making music particularly conducive to movement. We investigated these possibilities by asking participants to synchronize with isochronous auditory stimuli (target), while music and speech distractors were presented at one of various phase relationships with respect to the target. In Exp. 1, familiar musical excerpts and fragments of children poetry were used as distractors. The stimuli were manipulated in terms of beat/stress isochrony and average pitch to achieve maximum comparability. In Exp. 2, the distractors were well-known songs performed with lyrics, on a reiterated syllable, and spoken lyrics, all having the same meter. Music perturbed synchronization with the target stimuli more than speech fragments. However, music superiority over speech disappeared when distractors shared isochrony and the same meter. Music’s peculiar and regular temporal structure is likely to be the main factor fostering tight coupling between sound and movement.  相似文献   
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Insect and veteran trees are important parts of ecosystems and are usually included in ecological studies of forest management. The loss of veteran trees in woodlands and open landscapes would lead to the loss of saproxylic organisms—an important part of biodiversity. Hence, the persistence of many specialized insects depends on the presence of veteran trees scattered in woodlands (e.g. ancient wood pastures, game parks or protected areas), cities, towns and villages (e.g. avenues, parks or chateau parks) or open landscapes (e.g. fishpond dams, solitary trees or fruit orchards). Veteran tree conditions could be fairly well described by three components—diameter, age and microhabitats present. The problem is that diameter belongs to the most studied characteristics, while age and microhabitats, which can be quite complicated to measure, are much less studied. This paper illustrates that, due to this unbalanced use of indicators of veteran-tree conditions, we are still missing some important information on saproxylic species ecology—and sometimes only large trees might be studied, rather than real veterans. Although we already know that veteran trees are essential habitat for a range of saproxylic organisms, there are still gaps in our knowledge of the specific conditions that veteran trees provide. It is vital that these are quantified and understood so that this information can be used to conserve veteran trees and their associated species.  相似文献   
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Colorectal cancer (CRC) is one of the most common cause of death among neoplasms around the world. The environmental factors, like diet and obesity, are crucial in CRC pathogenesis by creating cancer-favorable microenvironment and hormonal changes. Adiponectin, the adipose tissue-specific hormone, is generally considered to negatively correlate with CRC development. The interleukin 6 (IL-6) is one of the most important pro-inflammatory cytokine connected with CRC, which is strongly inflammation-associated. The opioids are variable group substantially correlated with cancers - the endogenous opioids affect immune system and cell cycle including proliferation and cell death whereas exogenous opioids are leading clinically used analgesics in terminal cancer patients. In this review we discuss the involvement of adiponectin, IL-6 and opioids in CRC pathogenesis, their link with obesity, possible cross-talk and potential novel therapeutic approach in CRC treatment.  相似文献   
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Although the negative impact of timber stacks on populations of saproxylic beetles is a well-known phenomenon, there is relatively little data concerning the scale of this impact and its spatial aspect. Beech timber stored in the vicinity of the forest can act as an ecological trap for the Rosalia longicorn (Rosalia alpina), so in this study we have attempted to determine the spatial range of the impact of a network of timber stacks. Timber stacks in the species’ range in the study area were listed and monitored during the adult emergence period in 2014–2016. Based on published data relating to the species’ dispersal capabilities, buffers of four radii (500, 1000, 1600, 3000 m) were delineated around the stacks and the calculated ranges of potential impact. The results show that the percentage of currently known localities of the Rosalia longicorn impacted by stacks varies from 19.7 to 81.6%, depending on the assumed impact radius. The percentage of forest influenced by timber stacks was 77% for the largest-radius buffer. The overall impact of the ecological trap network is accelerated by fragmentation of the impact-free area. It was also found that forests situated close to the timber stacks where the Rosalia longicorn was recorded were older and more homogeneous in age and species composition than those around stacks where the species was absent. Such results suggest that timber stacks act as an ecological trap in the source area of the local population.  相似文献   
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The aim of this study was to conduct a survey assessing (a) the ochratoxin A (OTA) content in different samples of Astragalus propinquus root (AR), one of the fundamental herbs in traditional Chinese medicine, and (b) the rate of OTA transfer to AR decoctions that are traditionally used to reduce general weakness and increase overall vitality. A validated method of high-performance liquid chromatography with fluorescence detection (HPLC-FLD) was used to determine OTA concentrations in AR samples and AR decoctions. The limit of quantification was 0.35 ng/g; the recovery of the HPLC method for AR samples was 82%; and the relative standard deviation (SD) of repeatability was 2.6%. All 40 tested AR samples were positive, with a mean value of 451.0 ng/g (range, 28.8–1700.0 ng/g). The transfer rate of OTA to decoctions, from a naturally contaminated and homogenized AR sample (internal reference material) with a concentration of OTA of 288.9 ng/g?±?12.3 (SD), was 83.4%?±?8.5 (SD). We believe it is necessary to continue OTA monitoring in AR and other herbal products, estimate the actual human usual intake, and perform health risk assessment.  相似文献   
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