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Thyroid scintigraphy is commonly used for evaluation of cats with hyperthyroidism, with the thyroid‐to‐salivary ratio (T/S) being the most common method to quantify the degree of thyroid activity and disease. Calculation of thyroid‐to‐background ratios (T/B) or percent thyroidal uptake of 99mTcO?4 (TcTU) has only been reported in a few studies. The purpose of this prospective, cross‐sectional study was to evaluate a number of quantitative scintigraphic indices as diagnostic tests for hyperthyroidism, including the T/S, three different T/B, TcTU, and estimated thyroid volume. Of 524 cats referred to our clinic for evaluation of suspected hyperthyroidism, the diagnosis was confirmed (n = 504) or excluded (n = 20) based on results of a serum thyroid panel consisting of thyroxine (T4), triiodothyronine (T3), free T4 (fT4), and thyroid‐stimulating hormone (TSH) concentrations. In the hyperthyroid cats, median values for TcTU, T/S, and three T/B ratios were all significantly higher (P < 0.001) than values in euthyroid suspect cats or clinically normal cats. All scintigraphic parameters were relatively sensitive and specific as diagnostic tests for hyperthyroidism, but the T/S ratio had the highest test accuracy. The T/S ratio correlated strongly with the TcTU (r = 0.85). However, the TcTU had a higher and more significant correlation (P < 0.01) with serum T4 (r = 0.76 vs. 0.64), T3 (r = 0.77 vs. 0.64), and estimated thyroid volume (r = 0.62 vs. 0.38). Overall, calculation of TcTU is an accurate diagnostic test, but also appears to be the best parameter to predict the functional volume and metabolic activity of the feline adenomatous thyroid gland.  相似文献   
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许多国家的法律已经明确规定食用动物的屠宰应使用人道主义方式。一些消费者提出,先击昏动物再进行宰杀,是一种更人道、先进、符合消费者需求的屠宰方式。屠宰动物是残忍的,所以应当充分考虑如何改进宰杀手段及宰杀程序,最大限度地减少对屠宰动物的不良影响。本文综述了人道屠宰的科学原理,并详尽阐述了不同规模屠宰系统(例如:屠宰厂、农场),以及在疫病控制或出现自然灾害等需要大量屠宰活禽时如何改善动物福利的问题。  相似文献   
4.
The role that environmental contamination might play as a reservoir and a possible source of Methicillin-resistant Staphylococcus aureus (MRSA) for patients and personnel at equine veterinary hospitals remains undefined, as the environment has only been monitored during outbreaks or for short periods. Therefore, the objectives of this study were to determine the monthly presence, distribution, and characteristics of environmental MRSA at an equine hospital, and to establish patterns of contamination over time using molecular epidemiological analyses. For this purpose, a yearlong active MRSA surveillance was performed targeting the environment and incoming patients. Antimicrobial susceptibility testing, SCCmec typing, PFGE typing, and dendrographic analysis were used to characterize and analyze these isolates. Overall, 8.6% of the surfaces and 5.8% of the horses sampled were positive for MRSA. The most common contaminated surfaces were: computers, feed-water buckets, and surgery tables-mats. Ninety percent of the isolates carried SCCmec type IV, and 62.0% were classified as USA500. Molecular analysis showed that new pulsotypes were constantly introduced into the hospital throughout the year. However, maintenance of strains in the environment was also observed when unique clones were detected for 2 consecutive months on the same surfaces. Additionally, pulsotypes were circulating throughout several areas and different contact surfaces of the hospital. Based on these results, it is evident that MRSA is constantly introduced and frequently found in the equine hospital environment, and that some contact surfaces could act as “hot-spots”. These contaminated surfaces should be actively targeted for strict cleaning and disinfection as well as regular monitoring.  相似文献   
5.
Growing research interest in crop wild relatives (CWR) has highlighted their value for crop improvement, particularly to mitigate the impact of climate change and contribute to global food security. As most conservation activities are implemented at national level there is a requirement for each country to develop and implement a national CWR conservation strategy. This will contribute to regional and global CWR conservation actions and so help achieve CBD Aichi Targets 13 of improved genetic conservation of socio-economically important taxa. Cyprus has historically lacked systematic CWR conservation but is rich in CWR diversity being located in the eastern Mediterranean Vavilov centre and abutting the Fertile Crescent. Therefore a more coherent approach to CWR conservation is desirable. From an initial checklist of 1,722 Cypriot CWR taxa, 178 CWR were prioritized and eco geographic data was collated and analysed using GIS techniques. The Troodos and Pafos mountains are CWR hotspots and ten priority sites containing the genetic diversity of 74.7 % of priority CWR taxa were identified. These will form the basis of a national network of in situ genetic reserves and 78 priority CWR taxa that have no accessions in the national Cyprus gene bank are highlighted for collection and ex situ storage.  相似文献   
6.
Southwest China played a pivotal role in the spread of agriculture across East and Southeast Asia. Both rice and millet were important in the spread of populations and the expansion of agriculture into this region. Recent finds in the mountainous peripheries of Sichuan Province show that the earliest inhabitants of this region practiced a combination of broomcorn and foxtail millet agriculture (ca 4000?C2500 BC). These crops are adapted to high altitude and arid environments, which facilitated their movement across this region and eventually into the Tibetan Plateau. At around 2700 BC, a combined system of rice and foxtail millet agriculture appears suddenly in sites of the Baodun culture on the Chengdu Plain. The use of this double cropping system provided advantages to the inhabitants of this region in both risk reduction and yield. I argue that this had important consequences for spurring population growth, facilitating expansion into new territories and the development of social complexity.  相似文献   
7.
Renaud  Anaïs K  Savage  Jade  Adamowicz  Sarah J 《BMC ecology》2012,12(1):1-15

Background

Disturbance is an important process structuring ecosystems worldwide and has long been thought to be a significant driver of diversity and dynamics. In forests, most studies of disturbance have focused on large-scale disturbance such as hurricanes or tree-falls. However, smaller sub-canopy disturbances could also have significant impacts on community structure. One such sub-canopy disturbance in tropical forests is abscising leaves of large arborescent palm (Arececeae) trees. These leaves can weigh up to 15 kg and cause physical damage and mortality to juvenile plants. Previous studies examining this question suffered from the use of static data at small spatial scales. Here we use data from a large permanent forest plot combined with dynamic data on the survival and growth of > 66,000 individuals over a seven-year period to address whether falling palm fronds do impact neighboring seedling and sapling communities, or whether there is an interaction between the palms and peccaries rooting for fallen palm fruit in the same area as falling leaves. We tested the wider generalisation of these hypotheses by comparing seedling and sapling survival under fruiting and non-fruiting trees in another family, the Myristicaceae.

Results

We found a spatially-restricted but significant effect of large arborescent fruiting palms on the spatial structure, population dynamics and species diversity of neighbouring sapling and seedling communities. However, these effects were not found around slightly smaller non-fruiting palm trees, suggesting it is seed predators such as peccaries rather than falling leaves that impact on the communities around palm trees. Conversely, this hypothesis was not supported in data from other edible species, such as those in the family Myristicaceae.

Conclusions

Given the abundance of arborescent palm trees in Amazonian forests, it is reasonable to conclude that their presence does have a significant, if spatially-restricted, impact on juvenile plants, most likely on the survival and growth of seedlings and saplings damaged by foraging peccaries. Given the abundance of fruit produced by each palm, the widespread effects of these small-scale disturbances appear, over long time-scales, to cause directional changes in community structure at larger scales.  相似文献   
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服饰革命     
其实有谁会真的在乎别人穿什么?只要穿着舒适,只要能赢得比赛,就算是裹着报纸上场又有什么关系?上个世纪20年代,苏珊·朗格伦第一次穿着过膝短裙出现在球场上。人们蜂拥在场边,或许就单单为了欣赏她跑动接球时不经意地撩动裙摆露出的风光。由裙到裤,女士们用变换的衣装增添了网球的魅力,而现  相似文献   
10.
阿迪是妹妹养的一头下司犬。下司犬属中型犬,相貌凶猛,多为纯白毛或红毛,嘴脸多直立硬毛,犹如长针,其红鼻子、红眼睛、三角眼、虎头、尾直、散尾、猫耳朵,聪明善跑、忠厚老实,所以,该犬除有一定的观赏性外,常被当地苗族训练为“追山犬”,用于狩猎,夜间狩猎时,其身影犹如一条白龙穿梭在茫茫山岭中,因此当地苗族同胞又将其称为“白龙犬”。  相似文献   
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