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21.

Background and methods

Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.

Results

We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.

Conclusion

HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely.  相似文献   
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Introduction  

Fatigue is one of the most disabling symptoms associated with fibromyalgia that greatly impacts quality of life. Fatigue was assessed as a secondary objective in a 2-phase, 24-week study in outpatients with American College of Rheumatology-defined fibromyalgia.  相似文献   
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The willingness to utilise caves as shelters is held to have been important to early humans but dependent on pyrotechnology. Despite anecdotal evidence that non-human primates will also exploit caves there has as yet been no detailed account of such exploitation or of the reasons underlying it. Here we provide the first such data, on the frequency and patterning of the use of an underground cave system by baboons (Papio hamadryas)—and show that usage is determined, at least in part, by above-ground temperatures.  相似文献   
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Urbanisation and agriculture dramatically modify the landscapes available for use by wildlife, affecting key aspects of their ecology such as survival, foraging, predation, competition and reproductive success. Relatively little is known about the effects of urbanisation and agriculture on the genetic structure, gene flow and genetic diversity of wild species. Here, landscape genetic techniques were applied to compare local genetic diversity and gene flow between wood mouse populations in urban and arable landscapes. Using nine microsatellite markers, individuals were genotyped from six arable and seven urban sample sites. Inter‐population genetic differentiation was significantly greater in urban than arable habitat, while allele richness, private allele richness and heterozygosity were higher for arable sample sites, with varying degrees of significance. These suggest that urban habitat was sufficiently fragmented to limit gene flow. To test the effect of landscape features on gene flow, several cost‐distance measures were generated. Overland distance and Euclidean distance correlated best with inter‐population genetic differentiation in arable habitat, whereas distances that accommodated differences in habitat quality better explained differentiation in urban habitat. There was no evidence that margins adjacent to roads, rivers or railways facilitated gene flow. Together, the results indicate that urban landscapes expose wood mice to greater fragmentation in habitat quality than arable areas, leading to greater population isolation that is not mitigated by the presence of dispersal corridors.  相似文献   
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Water table management systems can be designed to alleviate soil water excesses and deficits, as well as reduce nitrate leaching losses in tile discharge. With this in mind, a standard tile drainage (DR) system was compared over 8 years (1991 to 1999) to a controlled tile drainage/subirrigation (CDS) system on a low-slope (0.05 to 0.1%) Brookston clay loam soil (Typic Argiaquoll) in southwestern Ontario, Canada. In the CDS system, tile discharge was controlled to prevent excessive drainage, and water was pumped back up the tile lines (subirrigation) to replenish the crop root zone during water deficit periods. In the first phase of the study (1991 to 1994), continuous corn (Zea mays, L.) was grown with annual nitrogen (N) fertilizer inputs as per local soil test recommendations. In the second phase (1995 to 1999), a soybean (Glycine max L., Merr.)-corn rotation was used with N fertilizer added only during the two corn years. In Phase 1 when continuous corn was grown, CDS reduced total tile discharge by 26% and total nitrate loss in tile discharge by 55%, compared to DR. In addition, the 4-year flow weighted mean (FWM) nitrate concentration in tile discharge exceeded the Canadian drinking water guideline (10 mg N l(-1)) under DR (11.4 mg N l(-1)), but not under CDS (7.0 mg N l(-1)). In Phase 2 during the soybean-corn rotation, CDS reduced total tile discharge by 38% and total nitrate loss in tile discharge by 66%, relative to DR. The 4-year FWM nitrate concentration during Phase 2 in tile discharge was below the drinking water guideline for both DR (7.3 mg N l(-1)) and CDS (4.0 mg N l(-1)). During both phases of the experiment, the CDS treatment caused only minor increases in nitrate loss in surface runoff relative to DR. Hence CDS decreased FWM nitrate concentrations, total drainage water loss, and total nitrate loss in tile discharge relative to DR. In addition, soybean-corn rotation reduced FWM nitrate concentrations and total nitrate loss in tile discharge relative to continuous corn. CDS and crop rotations with reduced N fertilizer inputs can thus improve the quality of tile discharge water substantially.  相似文献   
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