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991.
Abstract.  1. Catches in traps at 12 and 200 m above ground, and observations with entomological radar, were used to document the high-altitude windborne movements of carabid beetles over agricultural land in south-east U.K. during July 1999, 2000, 2002, and 2004.
2.  Notiophilus biguttatus (Fabricius) was found to be the most abundant species at altitude, with flights by reproductively immature adults resulting in millions of beetles passing through a 1 km2 window during the brief migration period in July 2002.
3. This result was unexpected in view of the conclusions of an earlier, classic Dutch study by den Boer and colleagues that classified N. biguttatus as a poorly dispersing species that tended to become isolated in remnants of natural habitat.
4. Reasons for the discrepancy between the two studies are discussed. It is hypothesised that the high mobility seen in the N. biguttatus populations results from a recent adaptation of the beetle's migration syndrome allowing it to exploit the mosaic of temporary habitat patches making up the increasingly intensive agroecosystems of northern Europe.  相似文献   
992.
993.

Cardiovascular disease is the major cause of death worldwide. Extensive cardiovascular biomarkers are available using blood tests but very few, if any, investigations have described non-invasive tests for cardiovascular biomarkers based on readily available hair samples. Here we show, first, that human hair proteins are post-translationally modified by arginine methylation (ArgMe). Using western blot, proteomic data mining and mass spectrometry, we identify several ArgMe events in hair proteins and we show that keratin-83 is extensively modified by ArgMe in the human hair. Second, using a preliminary cohort (n?=?18) of heterogenous healthy donors, we show that the levels of protein ArgMe in hair correlate with serum concentrations of a well-established cardiovascular biomarker, asymmetric dimethylarginine (ADMA). Compared to blood collection, hair sampling is cheaper, simpler, requires minimal training and carries less health and safety and ethical risks. For these reasons, developing the potential of hair protein ArgMe as clinically useful cardiovascular biomarkers through further research could be useful in future prevention and diagnosis of cardiovascular disease.

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994.
995.
Mycobacterium tuberculosis causes a variety of clinical outcomes determined by host as well as bacterial factors. M. tuberculosis disrupted in the mce1 operon causes increased mortality in immunocompetent mice. This operon is negatively regulated by mce1R (Rv0165c). We studied the role of mce1R in infection outcome in mice. At 5 x 10(4) tail vein infectious dose, the median survival time (MST) of mice infected with the mce1R mutant M. tuberculosis H37Rv was 293 days, while mice infected with the wild-type H37Rv survived more than 350 days (P < 0.0001). At a higher dose (5 x 10(6)), the MST of mutant-infected mice was 32 days, compared with 127 days for wild type-infected mice (P < 0.0001). With either tail vein or aerosol infection, mutant-infected mice developed larger granulomatous lesions in their lungs than mice infected with the wild type. Mutant-infected mice were unable to control the bacterial burden in the first 4 weeks of infection, but even after achieving control later, these mice succumbed to granulomatous pneumonia. These observations suggest that the early deregulated expression of the mce1 operon products determines later granulomatous tissue response. mce1 operon may homeostatically regulate the cell wall architecture in vivo that elicits a steady-state granuloma tissue response permitting M. tuberculosis to establish a long-term infection.  相似文献   
996.
FlyMine is a data warehouse that addresses one of the important challenges of modern biology: how to integrate and make use of the diversity and volume of current biological data. Its main focus is genomic and proteomics data for Drosophila and other insects. It provides web access to integrated data at a number of different levels, from simple browsing to construction of complex queries, which can be executed on either single items or lists.  相似文献   
997.
Partial body weight support (PBWS) systems used for rehabilitation status post-neurological and musculoskeletal pathologies and injuries are traditionally passive. Our purpose was to demonstrate the ability of an actively controlled PBWS system to provide a clinically relevant modulated support condition while investigating the impact of such a condition on the dynamics of gait. Using an instrumented treadmill and a motion capture system, we compared gait parameters of six healthy young adults (age 24-31 years) during unsupported walking to those under the assistance of two support conditions (a constant 20% body weight support, and a modulated support providing 20% body weight support during the loading response of each leg while allowing for an unsupported terminal stance). The modulated condition achieved support synchronized to gait cycle events with mean and maximum loading errors at the 20% body weight support level equal to 1.01 and 2.44 kg, respectively. Constant support significantly reduced sagittal plane hip angle range of motion and increased ankle platarflexion as compared to unsupported walking (p < 0.05). Also, a clear trend of decreased stride length was observed for constant support. No significant differences in these parameters were evident between the modulated support condition and unsupported walking. Ankle power generation and absorption both significantly decreased under constant support. The modulated support condition significantly increased ankle power absorption though showed no change in ankle power generation. The ability of the presented active PBWS device to provide individualized support schemes may offer new and possibly improved applications of PBWS rehabilitation.  相似文献   
998.
To study the contribution of T‐cell receptors (TCR) to resulting T‐cell responses, we studied three different human αβ TCRs, reactive to the same gp100‐derived peptide presented in the context of HLA‐A*0201. When expressed in primary CD8 T cells, all receptors elicited classic antigen‐induced IFN‐γ responses, which correlated with TCR affinity for peptide–MHC in the order T4H2 > R6C12 > SILv44. However, SILv44 elicited superior IL‐17A release. Importantly, in vivo, SILv44‐transgenic T cells mediated superior antitumor responses to 888‐A2 + human melanoma tumor cells upon adoptive transfer into tumor‐challenged mice while maintaining IL‐17 expression. Modeling of the TCR ternary complexes suggested architectural differences between SILv44 and the other complexes, providing a potential structural basis for the observed differences. Overall, the data reveal a more prominent role for the T‐cell receptor in defining host T‐cell physiology than traditionally assumed, while parameters beyond IFN‐γ secretion and TCR affinity ultimately determine the reactivity of tumor‐reactive T cells.  相似文献   
999.
Ecosystems - Woody debris (WD) stocks and fluxes are important components of forest carbon budgets and yet remain understudied, particularly in tropical forests. Here we present the most...  相似文献   
1000.
Highly variable phenotypic responses in mycorrhizal plants challenge our functional understanding of plant‐fungal mutualisms. Using non‐invasive high‐throughput phenotyping, we observed that arbuscular mycorrhizal (AM) fungi relieved phosphorus (P) limitation and enhanced growth of Brachypodium distachyon under P‐limited conditions, while photosynthetic limitation under low nitrogen (N) was exacerbated by the fungus. However, these responses were strongly dependent on host genotype: only the faster growing genotype (Bd3‐1) utilised P transferred from the fungus to achieve improved growth under P‐limited conditions. Under low N, the slower growing genotype (Bd21) had a carbon and N surplus that was linked to a less negative growth response compared with the faster growing genotype. These responses were linked to the regulation of N : P stoichiometry, couples resource allocation to growth or luxury consumption in diverse plant lineages. Our results attest strongly to a mechanism in plants by which plant genotype‐specific resource economics drive phenotypic outcomes during AM symbioses.  相似文献   
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