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61.
Within the Ecosystem-based fisheries management framework, we evaluated the changes over time in bycatch species of the European tuna purse-seine fishery operating in the eastern Atlantic Ocean. Bycatch data was collected during two scientific observer programs conducted in the late 1990s and in the late 2000s. Over these two time periods, we compared the temporal trends in bycatch species composition, the probability of occurrence of functional groups per fishing set, the spatio-temporal species richness and the potential impact on several species listed in the red list of the International Union for Conservation of Nature (IUCN). The analyses were performed separately on the two main fishing modes of the fleet, i.e. sets on free-swimming school sets and on fish aggregating devices (FADs). Owing data quality constraints, we did not estimate bycatch rates. Ours results showed that the species composition of sharks caught on FADs decreased over time. The total species richness was higher for FAD sets than for free-swimming school sets (87 vs. 61 species respectively), such difference is common between fishing modes worldwide. For the species catalogued as threatened by the IUCN, in free-swimming schools, 25.5 % of the species caught during first period increased to 30.4 % during second period, while for FAD-fishing the increase was from 28.8 % during first period to 34.9 % in second period. Ours findings suggest that tropical tuna purse-seine fisheries should include ecosystem-based governance of bycatch. Effective tuna management will require a combination of technological improvements for mitigating incidental catch of vulnerable species, best use of byproduct species, regulations in fishing practices and in spatial distribution of fishing effort, and international agreements that, together, can monitor and manage bycatch, reducing the negative fishing effects on the epipelagic ecosystem biodiversity.  相似文献   
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There is a natural symbiosis between vergence and vestibular responses. Deficits in vergence can lead to vertigo, disequilibrium, and postural instability. This study examines both vergence eye movements in patients with idiopathic bilateral vestibular loss, and their standing balance in relation to vergence. Eleven patients participated in the study and 16 controls. Bilateral loss of vestibular function was objectified with many tests; only patients without significant response to caloric tests, to video head impulse tests and without vestibular evoked myogenic potentials were included in the study.

Vergence testing (from 8 patients and 15 controls)

A LED display with targets at 20, 40, and 100 cm along the median plane was used to elicit vergence eye movements, recorded with the IRIS device.

Standing balance (11 patients and 16 controls)

Four conditions were run, each lasting 1 min: fixation of a LED at 40 cm (convergence of 9°), at 150 cm (convergence of 2.3°); this last condition was repeated with eyes closed. Comparison of the eyes closed-eyes open conditions at 150 cm allowed evaluation of the Romberg Quotient. In the forth condition, two LEDS, at 20 and at 100 cm, were light on, one after the other for 1 sec, causing the eyes to converge then diverge. Standing balance was recorded with an accelerometer placed at the back near the center of mass (McRoberts, Dynaport).

Results

Vergence

Relative to controls, convergence eye movements in patients showed significantly lower accuracy, lower mean velocity, and saccade intrusions of significantly higher amplitude.

Balance

The normalized 90% area of body sway was significantly higher for patients than for controls for all conditions. Yet, similarly to controls, postural stability was better while fixating at near (sustained convergence) than at far, or while making active vergence movements. We argue that vestibular loss deteriorates convergence, but even deficient, convergence can be helpful for postural control.  相似文献   
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Human APOBEC3 cytidine deaminases target and edit single-stranded DNA, which can be of viral, mitochondrial, or nuclear origin. Retrovirus genomes, such as human immunodeficiency virus (HIV) genomes deficient in the vif gene and the hepatitis B virus genome, are particularly vulnerable. The genomes of some DNA viruses, such as human papillomaviruses, can be edited in vivo and in transfection experiments. Accordingly, herpesviruses should be no exception. This is indeed the case for herpes simplex virus 1 (HSV-1) in tissue culture, where APOBEC3C (A3C) overexpression can reduce virus titers and the particle/PFU ratio ~10-fold. Nonetheless, A3A, A3G, and AICDA can edit what is presumably a small fraction of HSV genomes in an experimental setting without seriously impacting the viral titer. Hyperediting was found in HSV genomes recovered from 4/8 uncultured buccal lesions. The phenomenon is not restricted to HSV, since hyperedited Epstein-Barr virus (EBV) genomes were readily recovered from 4/5 established cell lines, indicating that episomes are vulnerable to editing. These findings suggest that the widely expressed A3C cytidine deaminase can function as a restriction factor for some human herpesviruses. That the A3C gene is not induced by type I interferons begs the question whether some herpesviruses encode A3C antagonists.  相似文献   
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Land abandonment is common in the Mediterranean Basin, a global biodiversity hotspot, but little is known about its impacts on biodiversity. To upscale existing case-study insights to the Pan-Mediterranean level, we conducted a meta-analysis of the effects of land abandonment on plant and animal species richness and abundance in agroforestry, arable land, pastures, and permanent crops of the Mediterranean Basin. In particular, we investigated (1) which taxonomic groups (arthropods, birds, lichen, vascular plants) are more affected by land abandonment; (2) at which spatial and temporal scales the effect of land abandonment on species richness and abundance is pronounced; (3) whether previous land use and current protected area status affect the magnitude of changes in the number and abundance of species; and (4) how prevailing landforms and climate modify the impacts of land abandonment. After identifying 1240 potential studies, 154 cases from 51 studies that offered comparisons of species richness and abundance and had results relevant to our four areas of investigation were selected for meta-analysis. Results are that land abandonment showed slightly increased (effect size  = 0.2109, P<0.0001) plant and animal species richness and abundance overall, though results were heterogeneous, with differences in effect size between taxa, spatial-temporal scales, land uses, landforms, and climate. In conclusion, there is no “one-size-fits-all” conservation approach that applies to the diverse contexts of land abandonment in the Mediterranean Basin. Instead, conservation policies should strive to increase awareness of this heterogeneity and the potential trade-offs after abandonment. The strong role of factors at the farm and landscape scales that was revealed by the analysis indicates that purposeful management at these scales can have a powerful impact on biodiversity.  相似文献   
67.
According to Charles Hauss, “[i]n the last few years, reconciliation has become one of the ‘hottest’ topics in the increasingly ‘hot’ field of conflict resolution” (2003, ?1). However, despite the apparent interest in this “hot” academic topic (which is becoming increasingly warm in Canada as our own Truth and Reconciliation Commission commences), reconciliation studies have been dominated by Truth-based approaches. The restrictions of these approaches, which emphasize objectivity and rationality, often elide the body and the primacy of emotions in the reparative process. This essay begins a conversation on the role of the body and emotion in the study of reconciliation by engaging the work being done in the social sciences with contemporary trends in critical theory and literature. I argue that by looking at the fundamental role the body plays on the “road to reconciliation” we can devise a more vital approach to conflict resolution and the various processes that make it up.  相似文献   
68.
This article describes the fabrication and use of microfluidic devices for investigating spatial orientation behaviors in nematode worms (Caenorhabditis elegans). Until now, spatial orientation has been studied in freely moving nematodes in which the frequency and nature of encounters with the gradient are uncontrolled experimental variables. In the new devices, the nematode is held in place by a restraint that aligns the longitudinal axis of the body with the border between two laminar fluid streams, leaving the animal's head and tail free to move. The content of the fluid streams can be manipulated to deliver step gradients in space or time. We demonstrate the utility of the device by identifying previously uncharacterized aspects of the behavioral mechanisms underlying chemotaxis, osmotic avoidance, and thermotaxis in this organism. The new devices are readily adaptable to behavioral and imaging studies involving fluid borne stimuli in a wide range of sensory modalities.  相似文献   
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