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The rapid decrease of biodiversity and limited resources for surveying it have forced researchers to devise short-cuts for biodiversity surveys and conservation planning. These short-cuts include environmental surrogates, higher taxon surrogates, indicator species and indicator groups. We considered indicator groups as surrogates for wholesale biodiversity and cross-taxon congruence in biodiversity patterns in littoral macroinvertebrates of boreal lakes. Despite the fact that we considered indicator groups amongst a wide variety of taxa, such as two-winged flies, mayflies, caddisflies, beetles, bugs and molluscs, none of the proposed groups possessed all of the qualities of a good indicator taxon for biodiversity surveys and conservation planning. We found generally weak, yet typically significant, relationships between the proposed indicator groups and remaining taxa in both species richness and assemblage similarity. Low congruence was paralleled by somewhat differing relationships of the taxonomic groups to various environmental features of lakes. Furthermore, the relationships of most indicator groups to the environmental features of lakes were not particularly strong. The present findings are unfortunate, because indicator groups did not perform well in predicting the wholesale biodiversity of littoral macroinvertebrates. Thus, there appears to be no short-cut for considering all groups of macroinvertebrates in biodiversity surveys, conservation planning and characterisation of environmental relationships of lake littoral assemblages.  相似文献   
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Subtilisin QK, which is newly identified as a fibrinolytic enzyme from Bacillus subtilis QK02, has the ability of preventing nitrotyrosine formation in bovine serum albumin induced by nitrite, hydrogen peroxide and hemoglobin in vitro verified by ELISA, Western-blot and spectrophotometer assay. Subtilisin QK also attenuates the fluorescence emission spectra of bovine serum albumin in the course of oxidation caused by nitrite, hydrogen peroxide and hemoglobin. Furthermore, subtilisin QK could suppress the transformation of oxy-hemoglobin to met-hemoglobin caused by sodium nitrite, but not the heat-treated subtilisn QK. Compared with some other fibrinolytic enzymes and inactivated subtilisin QK treated by phenylmethylsulfonylfluoride, the ability of inhibiting met-hemoglobin formation of subtilisin QK reveals that the anti-oxidative ability of subtilisin QK is not concerned with its fibrinolytic function. Additionally, nitrotyrosine formation in proteins from brain, heart, liver, kidney, and muscle of mice that is intramuscular injected the mixture of nitrite, hydrogen peroxide and hemoglobin is attenuated by subtilisin QK. Subtilisin QK can also protect Human umbilical vein endothelial cell (ECV-304) from the damage caused by nitrite and hydrogen peroxide.  相似文献   
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Herpes simplex virus (HSV) 1 stimulates type I IFN expression through the cGAS–STING–TBK1 signaling axis. Macrophages have recently been proposed to be an essential source of IFN during viral infection. However, it is not known how HSV‐1 inhibits IFN expression in this cell type. Here, we show that HSV‐1 inhibits type I IFN induction through the cGAS–STING–TBK1 pathway in human macrophages, in a manner dependent on the conserved herpesvirus protein ICP27. This viral protein was expressed de novo in macrophages with early nuclear localization followed by later translocation to the cytoplasm where ICP27 prevented activation of IRF3. ICP27 interacted with TBK1 and STING in a manner that was dependent on TBK1 activity and the RGG motif in ICP27. Thus, HSV‐1 inhibits expression of type I IFN in human macrophages through ICP27‐dependent targeting of the TBK1‐activated STING signalsome.  相似文献   
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Objectives

A number of studies have demonstrated the ontogenetic plasticity of long bone diaphyseal structure in response to mechanical loading. Captivity should affect mechanical loading of the limbs, but whether captive apes grow differently than wild apes has been debated. Here, we compare captive and wild juvenile and adult Gorilla to ascertain whether growth trajectories in cross‐sectional diaphyseal shape are similar in the two environments.

Materials and methods

A sample of young juvenile (n = 4) and adult (n = 10) captive Gorilla gorilla gorilla specimens, with known life histories, were compared with age‐matched wild G.g. gorilla (n = 62) and G. beringei beringei (n = 75) in relative anteroposterior to mediolateral bending strength of the femur, tibia, and humerus. Cross sections were obtained using peripheral quantitative CT.

Results

Captive and wild adult G.g. gorilla differed in bending strength ratios for all three bones, but these differences were not present in young juvenile G.g. gorilla. In comparisons across taxa, captive juvenile G.g. gorilla were more similar to wild G.g. gorilla than to G.b. beringei, while captive adult G.g. gorilla were more similar in shape to G.b. beringei in the hind limb.

Discussion

Captive and wild G. gorilla follow different ontogenetic trajectories in long bone diaphyseal shape, corresponding to environmental differences and subsequent modified locomotor behaviors. Differences related to phylogeny are most evident early in development.
  相似文献   
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Chlorophyll a fluorescence (ChlF) is closely related to photosynthesis and can be measured remotely using multiple spectral features as solar‐induced fluorescence (SIF). In boreal regions, SIF shows particular promise as an indicator of photosynthesis, in part because of the limited variation of seasonal light absorption in these ecosystems. Seasonal spectral changes in ChlF could yield new information on processes such as sustained nonphotochemical quenching (NPQS) but also disrupt the relationship between SIF and photosynthesis. We followed ChlF and functional and biochemical properties of Pinus sylvestris needles during the photosynthetic spring recovery period to answer the following: (a) How ChlF spectra change over seasonal timescales? (b) How pigments, NPQS, and total photosynthetically active radiation (PAR) absorption drive changes of ChlF spectra? (c) Do all ChlF wavelengths track photosynthetic seasonality? We found seasonal ChlF variation in the red and far‐red wavelengths, which was strongly correlated with NPQS, carotenoid content, and photosynthesis (enhanced in the red), but not with PAR absorption. Furthermore, a rapid decrease in red/far‐red ChlF ratio occurred in response to a cold spell, potentially relating to the structural reorganization of the photosystems. We conclude that all current SIF retrieval features can track seasonal photosynthetic dynamics in boreal evergreens, but the full SIF spectra provides additional insight.  相似文献   
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ABSTRACT

Chronotype is the temporal preference for activity and sleep during the 24 h day and is linked to mental and physical health, quality of life, and mortality. Later chronotypes, so-called “night owls”, consistently display poorer health outcomes than “larks”. Previous studies have suggested that preterm birth (<37 weeks of gestation) is associated with an earlier chronotype in children, adolescents, and young adults, but studies beyond this age are absent. Our aim was to determine if adults born preterm at very low birth weight (VLBW, ≤1500 g) display different chronotypes than their siblings. We studied VLBW adults, aged 29.9 years (SD 2.8), matched with same-sex term-born siblings as controls. A total of 123 participants, consisting of 53 sibling pairs and 17 unmatched participants, provided actigraphy-derived data on the timing, duration, and quality of sleep from 1640 nights (mean 13.3 per participant, SD 2.7). Mixed effects models provided estimates and significance tests. Compared to their siblings, VLBW adults displayed 27 min earlier sleep midpoint during free days (95% CI: 3 to 51 min, p =.029). This was also reflected in the timing of falling asleep, waking up, and sleep-debt corrected sleep midpoint. The findings were emphasized in VLBW participants born small for gestational age. VLBW adults displayed an earlier chronotype than their siblings still at age 30, which suggests that the earlier chronotype is an enduring individual trait not explained by shared family factors. This preference could provide protection from risks associated with preterm birth.  相似文献   
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