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101.
This study investigated the effect of using an artificial bright light on the entrainment of the sleep/wake cycle as well as the reaction times of athletes before the Rio 2016 Olympic Games. A total of 22 athletes from the Brazilian Olympic Swimming Team were evaluated, with the aim of preparing them to compete at a time when they would normally be about to go to bed for the night. During the 8-day acclimatization period, their sleep/wake cycles were assessed by actigraphy, with all the athletes being treated with artificial light therapy for between 30 and 45 min (starting at day 3). In addition, other recommendations to improve sleep hygiene were made to the athletes. In order to assess reaction times, the Psychomotor Vigilance Test was performed before (day 1) and after (day 8) the bright light therapy. As a result of the intervention, the athletes slept later on the third (p = 0.01), seventh (p = 0.01) and eighth (p = 0.01) days after starting bright light therapy. Regarding reaction times, when tested in the morning the athletes showed improved average (p = 0.01) and minimum reaction time (p = 0.03) when comparing day 8 to day 1. When tested in the evening, they showed improved average (p = 0.04), minimum (p = 0.03) and maximum reaction time (p = 0.02) when comparing day 8 to day 1. Light therapy treatment delayed the sleep/wake cycles and improved reaction times of members of the swimming team. The use of bright light therapy was shown to be effective in modulating the sleep/wake cycles of athletes who had to perform in competitions that took place late at night.  相似文献   
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Taurine bulls are highly susceptible to heat stress, leading to increased oxidative stress (OS) and impaired sperm viability. Polyunsaturated fatty acids (PUFAs) supplementation can be an alternative to improve semen quality, which also results in more sperm susceptibility to lipid peroxidation. Moreover, this deleterious effect can be exacerbated in animals affected by heat stress. Vitamin E is a key antioxidant that counteracts lipid peroxidation of sperm membrane caused by OS. Thus, combining PUFAs with vitamin E may improve sperm quality. In this context, this study aimed to evaluate the effect of interaction between PUFAs and vitamin E on sperm quality in Bos taurus bulls under testicular heat stress. Sixteen taurine bulls under testicular heat stress were randomly assigned in four groups: Control, Vitamin E, PUFA, and PUFA?+?Vitamin E. All groups lasted for 60 days. Samples were cryopreserved/thawed and analyzed for motility variables (CASA), membrane and acrosome integrity, mitochondrial activity, susceptibility to oxidative stress, DNA integrity, and sperm-binding capacity. Results showed that vitamin E had a beneficial effect on some sperm characteristics, whereas PUFA supplementation had an adverse effect when the two treatments were evaluated separately. Finally, the association between PUFAs and vitamin E did not improve sperm quality.  相似文献   
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The infraorder Cicadomorpha (Hemiptera) is a cosmopolitan species‐rich lineage of phytophagous insects. They have holocentric chromosomes and vary greatly in diploid number across families, with X0 as the predominant sex male mechanism. Here, we advance the understanding of chromosome mapping of repetitive elements of four families of cicadomorphan insects, the spittlebugs (Cercopidae), leafhoppers (Cicadellidae), and treehoppers (Aetalionidae and Membracidae). Sampled individuals from 19 species show considerable variation in diploid number, which may have originated from fusions between autosomes or between autosomes and the ancient X. The distribution of CMA3+ blocks, primarily observed in low numbers in autosomal regions, was a conserved trait. Likewise, fluorescence in situ hybridization (FISH) mapping revealed mainly one locus per haploid genome for the 18S rRNA gene and for H3, each of which is located on distinct chromosomes. Despite the extensive variation in the number of autosomes and sex systems, the number of loci of ribosomal and H3 genes remained stable and may reflect the ancestral genome organizations in these groups. These results shed light on the chromosomal‐level organization in Cicadomorpha and provide new insights into the evolutionary history of karyotypes and repetitive elements in this diverse insect lineage.  相似文献   
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Journal of Plant Growth Regulation - Cytokinin is a plant hormone and an important regulator of root growth. Reduced cytokinin levels increase root systems, which can be beneficial for crops grown...  相似文献   
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Lithium and valproate (VPA) are the most commonly prescribed mood-stabilizing drugs. Recently, several studies have reported their neuroprotective properties in several models of neural toxicity and, in some pathological conditions, large amounts of intracellular ATP can be released from damaged cells. In the present study, we investigate the potential neuroprotective effect of lithium and VPA against ATP-induced cell death in hippocampal slices of adult rats. Acute (in vitro) and chronic (in vivo) treatment at therapeutic doses with lithium or VPA significantly prevent the ATP-induced cell death. Lithium and VPA also exerted a synergic effect in the prevention of ATP-induced cell death. Moreover, hippocampal slices prepared from rats chronically treated with lithium or VPA presented a significant reduction in cell death in the presence of cytotoxic extracellular ATP. Although further investigations are necessary, our results show the neuroprotective effect of lithium and VPA against neuronal death induced by extracellular ATP, probably through a different pathway, and suggest novel uses of these drugs in neurogenerative diseases. L. C. Wilot and A. Bernardi equally contributed by this work.  相似文献   
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The aim of this study was to evaluate the chemical, antioxidant, and antimicrobial activity of the essential oils as well as the anatomy of the aerial parts from Baccharis aracatubaensis, Baccharis burchellii, and Baccharis organensis owing to the therapeutic potential of Baccharis. The volatile constituents were analyzed using GC/MS, the antioxidant activity was evaluated by oxygen radical absorbance capacity (ORACFL) and DPPH assays, and the antimicrobial activity by a microdilution technique. Of the 56 compounds identified, only seven (β‐caryophyllene, γ‐muurolene, bicyclogermacrene, β‐germacrene, spathulenol, τ‐muurolol, and α‐cadinol) were common in the three specimens studied. Of these, γ‐muurolene was found abundantly in B. aracatubaensis, while bicyclogermacrene was abundant in B. burchellii and B. organensis. The essential oils exhibited antioxidant activity in the ORACFL (>500.0 μmol TE g?1) and DPPH assays. However, they did not exhibit any antimicrobial activity. Secretory ducts and flagelliform glandular trichomes were observed in the anatomical study of all the Baccharis species studied.  相似文献   
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