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101.
Effect of hemi-circumferential periosteal transection and elevation in foals with experimentally induced angular limb deformities 总被引:1,自引:0,他引:1
Read EK Read MR Townsend HG Clark CR Pharr JW Wilson DG 《Journal of the American Veterinary Medical Association》2002,221(4):536-540
OBJECTIVE: To evaluate the effect of hemi-circumferential periosteal transection and elevation (HCPTE) in foals with, experimentally induced angular limb deformities. DESIGN: Prospective study. ANIMALS: 10 healthy foals. PROCEDURE: When foals were 30 days old, transphyseal bridge implants were placed on the lateral aspects of both distal radial physes. At 90 days of age (or when 15 degrees of angulation had developed), implants were removed, and HCPTE was performed on 1 limb. Foals were confined in small pens after surgery; the front feet of the foals were rasped weekly to maintain medial-to-lateral hoof wall balance. Dorsopalmar radiographic projections of the carpi were obtained before HCPTE and 2, 4, 6, 8, and 48 weeks later. RESULTS: At the time of transphyseal bridge removal and HCPTE, both treated and control limbs were observed to have a significantly greater carpal valgus, compared with the initial degree of angulation at 30 days of age. Following HCPTE or sham surgery, all limbs straightened over the subsequent 2 months of the study. Median angulation was not significantly different between treated and control limbs at any time during the study. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in foals with experimentally induced limb deformities, HCPTE was no more effective than stall confinement and hoof trimming alone for correction of the deformity. 相似文献
102.
Wilke VL Conzemius MG Besancon MF Evans RB Ritter M 《Journal of the American Veterinary Medical Association》2002,221(10):1426-1429
OBJECTIVE: To compare tibial plateau angle (TPA) between Greyhounds without damage to the cranial cruciate ligaments and Labrador Retrievers with and without damage to the cranial cruciate ligaments. DESIGN: Clinical study. ANIMALS: 87 client-owned dogs and 15 research colony Greyhounds. PROCEDURE: Standing position, horizontal-beam radiography was performed on Greyhounds and unaffected Labrador Retrievers to determine standing TPA. Lateral radiography of the stifle joint was performed on all dogs to determine traditional TPA. Age and body weight were recorded for unaffected and affected Labrador Retrievers. RESULTS: Greyhounds had mean standing TPA of 1.56 degrees and mean traditional TPA of 22.50 degrees. Unaffected Labrador Retrievers had mean standing TPA of 3.52 degrees and traditional TPA of 27.97 degrees. Affected Labrador Retrievers had mean traditional TPA of 25.55 degrees. No significant difference was found in mean standing TPA between Greyhounds and unaffected Labrador Retrievers. Standing TPAs in Greyhounds and unaffected Labrador Retrievers were not significantly different from a plane drawn parallel to the ground. Significant differences in traditional TPAs were detected among all 3 groups. CONCLUSIONS AND CLINICAL RELEVANCE: Greyhounds had mean traditional TPA of 22.50 degrees; similar angles should be considered normal for dogs. Although affected Labrador Retrievers had mean traditional TPA that was significantly greater than that of Greyhounds, the steepest TPA was found in unaffected Labrador Retrievers. Because Greyhounds and unaffected Labrador Retrievers had similar standing TPAs, we conclude that although TPA may be associated with damage to the cruciate ligaments, many dogs with a steep TPA do not develop cruciate ligament disease. 相似文献
103.
104.
Jesús Jaime Guerra-Santos Rosa María Cerón-Bretón Julia Griselda Cerón-Bretón Diana Lizett Damián-Hernández Reyna Cristina Sánchez-Junco Emma del Carmen Guevara Carrió 《林业研究》2014,25(1):129-134
We report the results of carbon stored in soil and aboveground biomass from the most important area of mangroves in Mexico,with dominant vegetation of Red mangrove(Rhizophora mangle L.),Black mangrove(Avicennia germinans L.),white mangrove(Laguncularia racemosa Gaertn.)and button mangrove(Conocarpus erectus L.).We sampled soils with high fertility during the dry season in 2009 and 2010at three sites on Atasta Peninsula,Campeche.We used allometric equations to estimate above ground biomass(AGB)of trees.AGB was higher in C.erectus(253.18±32.17 t·ha-1),lower in A.germinans(161.93±12.63t·ha-1),and intermediate in R.mangle(181.70±16.58 t·ha-1)and L.racemosa(206.07±19.12 t·ha-1).Of the three studied sites,the highest absolute value for AGB was 279.72 t·ha-1in button mangrove forest at any single site.Carbon stored in soil at the three sites ranged from36.80±10.27 to 235.77±66.11 t·ha-1.The Tukey test(p0.05)made for AGB was higher for black mangrove showed significant differences in soil carbon content between black mangrove and button mangrove.C.erectus had higher AGB compared with the other species.A.germinans trees had lower AGB because they grew in hypersaline environments,which reduced their development.C.erectus grew on higher ground where soils were richer in nutrients.AGB tended to be low in areas near the sea and increased with distance from the coast.A.germinans usually grew on recently deposited sediments.We assumed that all sites have the same potential to store carbon in soil,and then we found that there were no significant differences in carbon content between the three samples sites:all sites had potential to store carbon for long periods.Carbon storage at the three sampling sites in the state of Campeche,Mexico,was higher than that reported for other locations. 相似文献
105.
Emma L. Gillingham Jessica L. Hall Richard J. Birtles Kevin J. Bown Jolyon M. Medlock Robert Smith Kayleigh M. Hansford Jenny C. Warner Matthew Dryden Maaike E. Pietzsch 《Zoonoses and public health》2020,67(5):591-599
Lyme borreliosis (LB) is a tick‐borne disease caused by Borrelia burgdorferi sensu lato complex. In Europe, it is predominately transmitted by the sheep tick, Ixodes ricinus. Compared with other European countries, the United Kingdom (UK) is considered to have a low incidence of LB, although this varies regionally. To determine whether an association exists between tick bite consultations and LB incidence in the UK, retrospective questionnaires were sent to general practitioners (GPs) in high (Wiltshire), medium (Cumbria) and low (Wales) incidence areas. During 2011, the greatest incidence of consultations for tick bites was reported by GPs in Cumbria (204 consultations per 100,000 inhabitants), followed by Wiltshire (160 per 100,000 population) and Wales (54 per 100,000 population). In Wiltshire and Cumbria, GPs predominantly provided advice on tick removal, whilst Welsh GPs mostly advised patients on tick bite prevention. Focusing on Cumbria during 2011–2013, 72.5% of GPs removed ticks from patients (incidence of 101 consultations per 100,000 population), and more GPs diagnosed LB based on clinical features than laboratory‐confirmed diagnoses. To date, this is the first study to investigate the incidence of tick bite consultations and LB in England and Wales. 相似文献
106.
Species richness often peaks at intermediate productivity and decreases as resources become more or less abundant. The mechanisms that produce this pattern are not completely known, but several previous studies have suggested environmental heterogeneity as a cause. In experiments with evolving digital organisms and populations of fixed size, maximum species richness emerges at intermediate productivity, even in a spatially homogeneous environment, owing to frequency-dependent selection to exploit an influx of mixed resources. A diverse pool of limiting resources is sufficient to cause adaptive radiation, which is manifest by the origin and maintenance of phenotypically and phylogenetically distinct groups of organisms. 相似文献
107.
This paper investigates how Food Security (FS) is enacted in a southern region of Italy, characterized by high rates of mafias-related activity, arguing for the inclusion in the research of socio-cultural features and power relationships to explain how Alternative Food Networks (AFNs) can facilitate individual empowerment and community resilience. In fact, while FS entails legality and social justice, AFNs are intended as ‘instrumental value’ to reach the ‘terminal value’ of FS within an urban community in Sicily, as well as the space where citizens can act their individual and collective political food choices. Building on the social psychology literature and on ecologic-psychopolitical models (Christens and Perkins in J Commun Psychol 36(2):214–231, 2008), we discuss the case of Addiopizzo, a citizen project promoting the legality of their AFNs through the rejection of the payment of the pizzo (the protection money asked by racket) in the local food chain. The aim is to problematize the extent to which FS is able to re-localize ‘legal’ food in the market. This was done by reconnecting citizens to their space and territory in a socio-cultural context at risk where agro-food producers, retailers and consumers are not free to fully enact their citizenship agency because of a widespread illegal structure. The research findings show that Addiopizzo project enables citizens to act their social power: agro-food producers and retailers by subscribing to formal requirements based on values that reject racket; consumers by purchasing Addiopizzo labelled products; individuals and groups by participating further open-to-the-public activities that promote everyday politically oriented behaviour. The citizen empowerment and community resilience can be exerted within AFNs as they are interconnected paths of reflexivity and social learning within social adaptation. The paper concludes by advocating the role of urban communities as a pivotal agent to maintain positive social adaptations, where AFNs work as a socio-cultural synthesis of traditional and alternative producer–consumer ways of interaction, which are embodied in the FS value. 相似文献
108.
Dalley JW Fryer TD Brichard L Robinson ES Theobald DE Lääne K Peña Y Murphy ER Shah Y Probst K Abakumova I Aigbirhio FI Richards HK Hong Y Baron JC Everitt BJ Robbins TW 《Science (New York, N.Y.)》2007,315(5816):1267-1270
Stimulant addiction is often linked to excessive risk taking, sensation seeking, and impulsivity, but in ways that are poorly understood. We report here that a form of impulsivity in rats predicts high rates of intravenous cocaine self-administration and is associated with changes in dopamine (DA) function before drug exposure. Using positron emission tomography, we demonstrated that D2/3 receptor availability is significantly reduced in the nucleus accumbens of impulsive rats that were never exposed to cocaine and that such effects are independent of DA release. These data demonstrate that trait impulsivity predicts cocaine reinforcement and that D2 receptor dysfunction in abstinent cocaine addicts may, in part, be determined by premorbid influences. 相似文献
109.
110.
González-Barrio R Salmenkallio-Marttila M Tomás-Barberán FA Cantos E Espín JC 《Journal of agricultural and food chemistry》2005,53(15):5990-5996
White table grapes, var. Superior, were treated with UV-C light after harvest to increase stilbenes concentration, especially trans-resveratrol (RES), because this may be of relevance to the health-promoting properties assigned to these compounds. However, irradiated grapes also developed some browning on the surface on the third day of storage at 22 degrees C, with the subsequent detriment in the sensorial quality of the fruit. Possible causes for browning development during storage were investigated. The phenolic-related oxidative enzymes, polyphenol oxidase (PPO) and peroxidase (POD), were not specifically activated, and no new isoforms appeared upon UV-C treatment. UV-treated grapes had lower content of chlorophyll b than control grapes on the fourth day of storage, concomitant with the increase of pheophytins (chlorophyll degradation derived compounds). Microscopy data showed lower fluorescence emission in chloroplasts from the UV-treated samples, which may explain the decrease of chlorophylls content in the corresponding grape berries extracts. In addition, microscopy images showed cell wall thickening in the skin tissue of UV-treated grapes which could be considered as a general wound response in plant tissues. These results suggest that the development of browning in Superior white grapes after UV-C treatment is not closely related with the evolution of oxidative enzymes during storage and may be mainly due to the decrease of chlorophylls content. 相似文献