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11.
《Animal : an international journal of animal bioscience》2022,16(11):100657
To predict the impact of climate change on our beef animals and systems, we need a better understanding of how beef cattle traits are affected by varying weather and frequency of extreme events. We analysed the effect of minimum and maximum temperatures and average daily precipitation on a range of important carcass traits, including age at slaughter, cold carcass weight, carcass growth rate and conformation and fat score (N = >1.6 million), as well as calf 200-day live weight and growth rate (N = >270 000), using data from abattoirs across Britain (carcass traits) and calves in Scottish suckler beef herds (live weights and growth). Animals which experienced higher daily maximum and minimum temperatures had slower carcass and calf growth rates. Increased precipitation also led to poorer cold carcass weights, conformation scores, calf 200-day weights and calf growth. We also analysed the effect of frequency of extreme weather events, including heatwaves, cold waves, and dry and wet days. The frequency of heatwaves, dry and wet days were shown to have significant negative effects on almost all traits considered, for example, predicting that an increase in the frequency of heatwaves by 1 day per 100 days of life would reduce cold carcass weights by about 200 g and increase age at slaughter by about 3 days. Results show that varying weather and frequency of extreme weather, across the lifetime of a beef animal, influences traits which affect the potential profit for a beef farmer. These effects may be due to several factors, including direct effects on the animal, as well as feed availability and management decisions made by the farmer. However, there is potential to mitigate negative effects through a range of animal management strategies. 相似文献
12.
目的:研究彩色多普勒超声联合癌胚抗原(CEA)和糖链抗原15-3(CA15-3)检测在乳腺癌诊断中的价值。方法:选取我院2010年2月~2011年1月的98例乳腺肿块患者,患者均行彩色多普勒超声检查,采用化学发光免疫法检测血清CEA、CA-153水平,并结合常规活检和术后诊断进行统计学分析。对比三者联合检测与单一检测的敏感性、准确性。结果:彩色多普勒超声、血清CEA、CA15-3检查及三者联合检查诊断乳腺癌的敏感性、准确性分别为86.11%、30.56%、47.22%、97.22%和88.78%、73.47%、77.55%、94.90%,联合检查的准确性、敏感性高于单一检查,差异有统计学意义(P0.05)。结论:彩色多普勒超声检测方法联合CEA、CA15-3检查可提升乳腺癌诊断的准确性和敏感性,降低漏诊率。 相似文献
13.
目的:探讨彩色多普勒超声(CDFI)对乳腺癌新辅助化疗(NCT)疗效评价的临床应用价值。方法:选取2013年1月~2013年12月在我院接受新辅助化疗后行手术治疗的女性乳腺癌患者55例,以病理学评价为金标准,化疗后根据化疗效果分为有效组和无效组,利用CDFI观察患者NCT前后病灶超声指标、病灶内血流分级及阻力指数(RI)值变化。结果:55例患者中,临床触诊疗效评价符合率为36.4%,敏感度为60.7%;CDFI评价符合率为70.9%,敏感度为85.7%。CDFI检查显示,乳腺癌NCT后原发肿瘤病灶大小显著缩小,边界多清晰可见,内部回声及后方回声倾向正常。有效组NCT前后病灶内的血流类型和RI值变化有统计学意义(P0.05),无效组NCT前后病灶内的血流类型和RI值无明显变化(P0.05)。结论:CDFI技术可对乳腺癌NCT前后病灶大小及病灶内部血流动力学变化提供客观参数,是评价乳腺癌NCT疗效的有效方法。 相似文献
14.
目的:三维超声心动图评估不同年龄段和性别主动脉瓣二叶畸形(bicuspid aortic valve malformation,BAV)的应用价值。方法:超声心动图检测我院2012年6月至2014年9月70例BAV患者,根据年龄段分为4组,≤20岁年龄组7例,21-40岁年龄组14例,41-60岁年龄组30例,≥60岁年龄组19例;根据性别分为2组,男性42例,女性28例。测量不同病例分组的主动脉窦部及升部内径、室间隔厚度、左心功能及左房横径,比较主动脉瓣狭窄、关闭不全、钙化及脱垂四个合并症发生率。结果:在心脏结构指标方面,年龄段分组室间隔厚度≥60岁年龄组12.37±1.64 mm高于≤20岁年龄组10.43±2.22 mm和21-40岁年龄组11.00±1.92 mm;左房横径41-60岁年龄组38.73±7.95 mm和≥60岁年龄组40.05±9.71 mm高于≤20岁年龄组29.86±1.86 mm。性别分组左心功能女性64.18±6.04%高于男性58.71±11.28%。在合并症发生率方面年龄段分组主动脉瓣狭窄41-60岁年龄组80%、≥60岁年龄组84%高于21-40岁年龄组50%,性别分组狭窄男性81%大于女性54%,关闭不全女性79%大于男性50%。结论:三维超声心动图诊断BAV可获得更加全面、具体、直观的诊断信息,BAV的超声表现与患者年龄段和性别密切相关。 相似文献
15.
We report non‐invasive 3D imaging of capillary blood flow within human finger cuticle by the use of Doppler optical microangiography (DOMAG) and ultra‐high sensitive optical microangiography (UHS‐OMAG) techniques. Wide velocity range DOMAG method is applied to provide red blood cell (RBC) axial velocity mapping in capillary loops with ranges of ±0.9 mm/s and ±0.3 mm/s. Additionally, UHS‐OMAG technique is engineered to acquire high resolution image of capillary morphology. The presented results are promising to facilitate clinical trials of treatment and diagnosis of various diseases such as diabetes, Raynaud's phenomenon, and connective tissue diseases by quantifying cutaneous blood flow changes within human finger cuticle. (© 2013 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
16.
In situ adaptive response to climate and habitat quality variation: spatial and temporal variation in European badger (Meles meles) body weight 下载免费PDF全文
Andrew W. Byrne Ursula Fogarty James O'Keeffe Chris Newman 《Global Change Biology》2015,21(9):3336-3346
Variation in climatic and habitat conditions can affect populations through a variety of mechanisms, and these relationships can act at different temporal and spatial scales. Using post‐mortem badger body weight records from 15 878 individuals captured across the Republic of Ireland (7224 setts across ca. 15 000 km2; 2009–2012), we employed a hierarchical multilevel mixed model to evaluate the effects of climate (rainfall and temperature) and habitat quality (landscape suitability), while controlling for local abundance (unique badgers caught/sett/year). Body weight was affected strongly by temperature across a number of temporal scales (preceding month or season), with badgers being heavier if preceding temperatures (particularly during winter/spring) were warmer than the long‐term seasonal mean. There was less support for rainfall across different temporal scales, although badgers did exhibit heavier weights when greater rainfall occurred one or 2 months prior to capture. Badgers were also heavier in areas with higher landscape habitat quality, modulated by the number of individuals captured per sett, consistent with density‐dependent effects reducing weights. Overall, the mean badger body weight of culled individuals rose during the study period (2009–2012), more so for males than for females. With predicted increases in temperature, and rainfall, augmented by ongoing agricultural land conversion in this region, we project heavier individual badger body weights in the future. Increased body weight has been associated with higher fecundity, recruitment and survival rates in badgers, due to improved food availability and energetic budgets. We thus predict that climate change could increase the badger population across the Republic of Ireland. Nevertheless, we emphasize that, locally, populations could still be vulnerable to extreme weather variability coupled with detrimental agricultural practice, including population management. 相似文献
17.
Arnaud Da Silva Mihai Valcu Bart Kempenaers 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1667)
Artificial night lighting is expanding globally, but its ecological consequences remain little understood. Animals often use changes in day length as a cue to time seasonal behaviour. Artificial night lighting may influence the perception of day length, and may thus affect both circadian and circannual rhythms. Over a 3.5 month period, from winter to breeding, we recorded daily singing activity of six common songbird species in 12 woodland sites, half of which were affected by street lighting. We previously reported on analyses suggesting that artificial night lighting affects the daily timing of singing in five species. The main aim of this study was to investigate whether the presence of artificial night lighting is also associated with the seasonal occurrence of dawn and dusk singing. We found that in four species dawn and dusk singing developed earlier in the year at sites exposed to light pollution. We also examined the effects of weather conditions and found that rain and low temperatures negatively affected the occurrence of dawn and dusk singing. Our results support the hypothesis that artificial night lighting alters natural seasonal rhythms, independently of other effects of urbanization. The fitness consequences of the observed changes in seasonal timing of behaviour remain unknown. 相似文献
18.
19.
Kevin M. Ringelman Christopher K. Williams Patrick K. Devers John M. Coluccy Paul M. Castelli Kurt A. Anderson Jacob L. Bowman Gary R. Costanzo Dane M. Cramer Matt T. Dibona Michael W. Eichholz Min Huang Benjamin Lewis Jr. Dawn M. Plattner Tina Yerkes 《The Journal of wildlife management》2015,79(8):1298-1307
20.
RONGJIANG WANG OTSO OVASKAINEN YUNDONG CAO HOUQIANG CHEN YAN ZHOU CHONGREN XU ILKKA HANSKI 《Ecological Entomology》2011,36(2):251-260
1. Habitat fragmentation may lead to natural selection on dispersal rate and other life‐history traits. Both theoretical analyses and empirical studies suggest that habitat fragmentation may select either for increased or decreased dispersal depending on the traits of the species and the characteristics of the landscape. 2. Dispersal and movement rates in Glanville fritillary butterflies (Melitaea cinxia) originating from a continuous landscape in China and from a highly fragmented landscape in Finland were compared using three different methods. 3. The methods included replicated mark‐release‐recapture (MRR) experiments conducted in the natural environments in China and Finland, tracking with harmonic radar of captive‐reared but free‐flying butterflies in a common environment in the field, and replicated common garden experiments in a large outdoor population cage. 4. The results were largely consistent, showing that butterflies from the more continuous landscape in China had a lower movement rate than butterflies originating from the fragmented landscape in Finland. Butterflies originating from newly‐established populations in Finland moved significantly longer distances than butterflies originating from old populations in Finland or from China, demonstrating significant intra‐specific variation in dispersal rate in Finland. These results are consistent with model predictions for the Glanville fritillary. 5. The tracking experiment revealed a result that would have been impossible to obtain with MRR experiments: movement rate was influenced by a significant interaction between population origin (China vs. Finland) and ambient air temperature. 相似文献