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51.
Abstract

The way in which foraging wasps use cues for prey location and choice appears to depend on both the context and on the type of prey. Vespula germanica is an opportunistic, generalist prey forager, and individual wasp foragers often return to hunt at sites of previous hunting success. In this paper, we studied which cues are used by this wasp when relocating a food source. Particularly we analysed the response to a displaced visual cue versus a foraging location at which either honey or cat food had been previously presented. We conclude that location is used over a displaced visual cue for directing wasp hovering, although the landing response is directed differently according to bait type. When wasps are exploiting cat food, location also elicits landing, but if they are exploiting honey, a displaced visual cue elicits landing more frequently than location.  相似文献   
52.
Today, the search for new energy sources continues unabated throughout the North. At the same time, scientists are increasingly concerned over the degradation of the Arctic and sub-Arctic environment stemming from fossil fuel and other large-scale energy projects already underway. Similar apprehensions are expressed by indigenous peoples who have often suffered from the impact of such development. While the most dramatic evidence of environmental devastation and social disruption is found in the Russian North, serious problems are by no means confined to that area alone. Nor are these negative effects necessarily limited to the borders of the country in which they originated. Indeed, the deleterious environmental impact of our global industrial economy has become sufficiently profound that social analysts are beginning to ask whether development strategies that cause such harm to the Arctic and sub-Arctic region should continue; and if not, what should replace them. This article addresses these issues as they relate to questions of sustainability, equity, political empowerment, and human rights in northwest Siberia and northern North America.  相似文献   
53.
Summary The genusPlebeia has a special significance for the study of social evolution of stingless bees: morphologically primitive, its species display a wealth of behavioural evolution, especially with respect to the oviposition process. We comparePlebeia remota with the few other members of the genus studied so far.Related to its subtropical geographical range, brood production is seasonal (there is no brood in the colony in colder months), and adult workers occur as summer and winter bees. The nest is in tree cavities, and the involucrum is absent or restricted to the winter period. Brood cells are arranged in horizontal combs, and new cells are built completely synchronously. Each series consists of up to 50 cells, their number being mainly dependent on colony size. Construction speed is remarkably constant, allowing 4–6 batches per 24 hours. Cell building and provisioning are activities of a small group of specialized workers.The oviposition cycle follows the classical subdivisions for stingless bees. During the patrolling phase a worker may offer a trophic egg in a most remarkable way: while retreating backward from the queen she bends the abdomen under thorax and head, and lays an egg on the comb. This egg is eaten by the queen or a worker.The provisioning, oviposition and operculation of all cells occur simultaneously, each cell is provisioned by 4–9 workers. Localization of a cell by the queen may be facilitated by its characteristic guard, which defends the cell against the approaching queen. The degree of synchronization within a batch is very high: the duration per cell lasts 420–950 sec, the batch of up till 50 cells needs only 557–1160 sec. Operculation is done by a worker that was not involved in the previous steps.Males are generally produced by the queen. Several male producing cycles per year occur. In orphan colonies laying workers give rise to males, and in queenright colonies workers may occasionally reproduce as well.Division of labour follows the general pattern for stingless bees; however, cell building and provisioning are activities of a specialized group of workers.  相似文献   
54.
The combination of highly equipped smartphones, with the increased use of social media, has offered a wide database. Given this, citizen science can be used to record and monitor non-native fish fauna, target new samples and collaborate with monitoring occurrences in new areas. We aimed to demonstrate the efficiency of social media in citizen science as a tool to cooperate with monitoring studies of non-native species. Consequently, we determined the occurrence points of S. brasiliensis in the Iguaçu River basin, indicating sites of greatest occurrence and analyzing the impact of the invasion on the native fauna of the basin. Files and information available on the YouTube® and Facebook® media platforms were used as data, was carried out from April 2019 to April 2020. The results were 40 records, 22 videos obtained from Youtube, and seven videos and 11 photos from Facebook, the oldest record was from April 2013, while the largest number of posts was in 2016. Fish records available from online platforms can reveal the occurrence and progressive dispersion of species, in the context of biological invasions, these tools can be of great value in studies that aim to follow the progress of introduced species, contributing by helping to direct new sampling programs and corroborating the occurrence of species in new areas in conjunction with standard monitoring programs. Based on citizen science records, it was possible to update the range of occurrence of the non-native S. brasiliensis in the Iguaçu River basin, cooperating with scientific knowledge. Innovative monitoring and control measures are necessary to deal with invasive species, with citizen science proving to be competent for determining the occurrence of species and showing promise in the entire field of ichthyology.  相似文献   
55.
56.
Compromised TLR-mediated chronic inflammation contributes to bacterial infection-caused chronic suppurative otitis media, but the mechanisms are unclear. The present study examined the expression status of nuclear erythroid 2-related factor 2 (Nrf2) and TLRs in human middle-ear mucosae tissues collected from patients with chronic suppurative otitis media, chronic otitis media and non-otitis media, and found that Nrf2 was high-expressed, whereas TLR4, instead of other TLRs, was low expressed in chronic suppurative otitis media compared to chronic otitis media and non-chronic otitis media groups. Consistently, inflammatory cytokines were significantly up-regulated in the chronic suppurative otitis media group, instead of the chronic otitis media and non-chronic otitis media groups. Next, LPS-induced acute otitis media and chronic suppurative otitis media models in mice were established, and high levels of inflammatory cytokines were sustained in the mucosae tissues of chronic suppurative otitis media mice compared to the non-otitis media and acute otitis media groups. Interestingly, continuous low-dose LPS stimulation promoted Nrf2 expression, but decreased TLR4 levels in chronic suppurative otitis media mice mucosae. In addition, knock-down of Nrf2 increased TLR4 expression levels in chronic suppurative otitis media mice, and both Nrf2 ablation and TLR4 overexpression inhibited the pro-inflammatory cytokine expression in chronic suppurative otitis media. Finally, we found that both Nrf2 overexpression and TLR4 deficiency promoted chronic inflammation in LPS-induced acute otitis media mice models. Taken together, knock-down of Nrf2 reversed chronic inflammation to attenuate chronic suppurative otitis media by up-regulating TLR4.  相似文献   
57.
A direct HPLC method was developed for the enantioseparation of pantoprazole using macrocyclic glycopeptide-based chiral stationary phases, along with various methods to determine the elution order without isolation of the individual enantiomers. In the preliminary screening, four macrocyclic glycopeptide-based chiral stationary phases containing vancomycin (Chirobiotic V), ristocetin A (Chirobiotic R), teicoplanin (Chirobiotic T), and teicoplanin-aglycone (Chirobiotic TAG) were screened in polar organic and reversed-phase mode. Best results were achieved by using Chirobiotic TAG column and a methanol-water mixture as mobile phase. Further method optimization was performed using a face-centered central composite design to achieve the highest chiral resolution. Optimized parameters, offering baseline separation (resolution = 1.91 ± 0.03) were as follows: Chirobiotic TAG stationary phase, thermostated at 10°C, mobile phase consisting of methanol/20mM ammonium acetate 60:40 v/v, and 0.6 mL/min flow rate. Enantiomer elution order was determined using HPLC hyphenated with circular dichroism (CD) spectroscopy detection. The online CD signals of the separated pantoprazole enantiomers at selected wavelengths were compared with the structurally analogous esomeprazole enantiomer. For further verification, the inline rapid, multiscan CD signals were compared with the quantum chemically calculated CD spectra. Furthermore, docking calculations were used to investigate the enantiorecognition at molecular level. The molecular docking shows that the R-enantiomer binds stronger to the chiral selector than its antipode, which is in accordance with the determined elution order on the column—S- followed by the R-isomer. Thus, combined methods, HPLC-CD and theoretical calculations, are highly efficient in predicting the elution order of enantiomers.  相似文献   
58.
Video displays for behavioral research lend themselves particularly well to studies with chimpanzees (Pan troglodytes), as their vision is comparable to humans', yet there has been no formal test of the efficacy of video displays as a form of social information for chimpanzees. To address this, we compared the learning success of chimpanzees shown video footage of a conspecific compared to chimpanzees shown a live conspecific performing the same novel task. Footage of an unfamiliar chimpanzee operating a bidirectional apparatus was presented to 24 chimpanzees (12 males, 12 females), and their responses were compared to those of a further 12 chimpanzees given the same task but with no form of information. Secondly, we also compared the responses of the chimpanzees in the video display condition to responses of eight chimpanzees from a previously published study of ours, in which chimpanzees observed live models. Chimpanzees shown a video display were more successful than those in the control condition and showed comparable success to those that saw a live model. Regarding fine-grained copying (i.e. the direction that the door was pushed), only chimpanzees that observed a live model showed significant matching to the model's methods with their first response. Yet, when all the responses made by the chimpanzees were considered, comparable levels of matching were shown by chimpanzees in both the live and video conditions.  相似文献   
59.
Taking into consideration that shift work has a wide-ranging impact on circadian and sleep functioning, it seems likely that shift work increases the risk of a general sleep disturbance, spread out over a multitude of comorbid sleep disorders. The aim of the present study is to analyze and present the sleep disorder data of 250 shift workers and 971 permanent day workers, taken from a nationally representative sample. Additional data concerning duration, timing, and quality of sleep, daytime functioning and social/family variables were added to the analyses. The results showed that the shift workers experienced significantly more difficulties with the variability of their sleep times, reported more napping and considered themselves more as poor sleepers than the day workers. Most importantly, shift work, in comparison with day work, appeared associated with a significantly higher prevalence of the clinical, International Classification of Sleep Disorders’ defined symptoms of nearly all main sleep disorders (including shift work disorder). For shift workers, the prevalence of a general sleep disturbance was 39.0% (95%CI 33.2 – 45.2), significantly higher than for day workers (24.6%, 95%CI 22.0 – 27.4). Moreover, shift workers were characterized by high levels of sleep disorder comorbidity. In addition, exclusively for shift workers, the prevalence of disordered sleep systematically decreased across decades of life and was considerably higher for single versus partnered shift workers. This study adds to the insight into the interacting factors that determine shift work coping and may play a role in occupational health interventions aimed at reducing sleep problems and thus improving the resilience and tolerance of the shift worker.  相似文献   
60.
Atp1a3 is the Na‐pump alpha3 subunit gene expressed mainly in neurons of the brain. Atp1a3‐deficient heterozygous mice (Atp1a3+/?) show altered neurotransmission and deficits of motor function after stress loading. To understand the function of Atp1a3 in a social hierarchy, we evaluated social behaviors (social interaction, aggression, social approach and social dominance) of Atp1a3+/? and compared the rank and hierarchy structure between Atp1a3+/? and wild‐type mice within a housing cage using the round‐robin tube test and barbering observations. Formation of a hierarchy decreases social conflict and promote social stability within the group. The hierarchical rank is a reflection of social dominance within a cage, which is heritable and can be regulated by specific genes in mice. Here we report: (1) The degree of social interaction but not aggression was lower in Atp1a3+/? than wild‐type mice, and Atp1a3+/? approached Atp1a3+/? mice more frequently than wild type. (2) The frequency of barbering was lower in the Atp1a3+/? group than in the wild‐type group, while no difference was observed in the mixed‐genotype housing condition. (3) Hierarchy formation was not different between Atp1a3+/? and wild type. (4) Atp1a3+/? showed a lower rank in the mixed‐genotype housing condition than that in the wild type, indicating that Atp1a3 regulates social dominance. In sum, Atp1a3+/? showed unique social behavior characteristics of lower social interaction and preference to approach the same genotype mice and a lower ranking in the hierarchy.  相似文献   
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