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101.
102.
Jenner F Edwards RB Voss JR Southwood L Markel MD Richardson DW 《American journal of veterinary research》2005,66(1):36-42
OBJECTIVE: To evaluate the use of hydrothermal ablation of articular cartilage for arthrodesis in horses through investigation of the effects of joint lavage with physiologic saline (0.9% NaCI) solution (80 degrees C) for various treatment times on chondrocyte viability in the articular cartilage of the metacarpophalangeal and metatarsophalangeal joints of cadaveric horse limbs. Sample Population-7 pairs of metacarpophalangeal and 8 pairs of metatarsophalangeal joints from 8 Thoroughbreds. PROCEDURE: The horses were euthanatized for reasons unrelated to musculoskeletal disease. On a random basis, 1 joint of each pair underwent intra-articular lavage for 5, 10, or 15 minutes with heated saline solution (80 degrees C); the other joint underwent sham treatment of similar duration with saline solution at 22 degrees C (control). Cartilage samples from the distal articular surface of metacarpus III (or metatarsus III), the proximal surface of the proximal phalanx, and the lateral and medial proximal sesamoid bones were assessed for chondrocyte viability via confocal microscopy and viability staining following enzymatic digestion. RESULTS: Compared with the control joints, findings of both viability assays indicated that the percentage of sites containing viable chondrocytes in heat-treated joints was decreased.Treatment hazard ratios of 0.048 (confocal microscopy) and 0.2 (digestion assay) were estimated. Histologically, periarticular soft tissues had minimal detrimental effects after heat treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Ex vivo intra-articular lavage with saline solution at 80 degrees C resulted in the death of almost all articular chondrocytes in the joint. This technique may be a satisfactory method for extensive cartilage ablation when performing arthrodesis by minimally invasive techniques. 相似文献
103.
Histomorphometric analysis of the proximal portion of the femur in dogs with moderate osteoarthritis
OBJECTIVE: To describe the histomorphometric properties of epiphyseal and metaphyseal trabecular bone of the proximal portion of the femur of dogs with moderate osteoarthritis. SAMPLE POPULATION: Proximal portions of a femour from 24 dogs. PROCEDURE: The proximal portion of a femur was obtained from each dog. Eleven and thirteen specimens were sectioned in the transverse and coronal planes, respectively. Three evenly spaced sections from each specimen were chosen, surface stained, and digitized, and the stained areas were preferentially selected. Custom software was used for histomorphometric analysis of each section. A mixed-model analysis was used to evaluate the effect of slice location and region on 6 parameters, and a Fisher protected t test was used when differences were detected. RESULTS: There was a significant difference between the femoral head and femoral neck for all parameters tested. In coronal sections, the femoral neck was significantly more anisotropic than the femoral head. In transverse sections, the craniolateral region of the femoral neck was significantly more anisotropic than the caudomedial and craniomedial regions. CONCLUSIONS AND CLINICAL RELEVANCE: There is a predictable cancellous microarchitecture in the proximal portion of femurs from dogs with moderate osteoarthritis. Trabeculae are more numerous, thicker, and closer together but more randomly arranged in the femoral head than in the femoral neck. Dogs with moderate osteoarthritis had an increase in trabecular anisotropy in the craniolateral region of the femoral neck. However, there was no corresponding increase in trabecular alignment of the proximomedial region of the femoral head. Results support an association between trabecular alignment and the progression of osteoarthritis. 相似文献
104.
Effects of sub-minimum inhibitory concentration antibiotic levels and temperature on growth kinetics and outer membrane protein expression in Mannheimia haemolytica and Haemophilus somnus
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Brenda Y. Reeks Franklin R. Champlin Daniel B. Paulsen Daniel W. Scruggs Mark L. Lawrence 《Canadian journal of veterinary research》2005,69(1):1-10
The objective of this study was to determine the effects of sub-minimum inhibitory concentrations (sub-MICs) of 2 veterinary antibiotic preparations, chlortetracycline (CTC) and chlortetracycline-sulfamethazine (CTC + SMZ), on growth kinetics and outer membrane protein expression in Mannheimia haemolytica and Haemophilus somnus at normal and febrile body temperatures. Sub-minimum inhibitory concentrations of both antibiotics reduced the growth rates of M. haemolytica and H. somnus. Growth of both species was not inhibited when grown at 41 degrees C compared to 37 degrees C. There was no detectable consistent effect of antibiotic or temperature on outer membrane protein expression for either species. Our study indicates that sub-MIC levels of CTC and CTC + SMZ markedly impair growth of clinical M. haemolytica and H. somnus isolates, potentially allowing more effective host clearance during infection. 相似文献
105.
Senior M 《Veterinary anaesthesia and analgesia》2005,32(4):193-200
OBJECTIVES: To review information on the pathogenesis, diagnosis and treatment of post-anaesthetic pulmonary oedema in horses. DATABASES USED: Pubmed 1970-present, personal files. 相似文献
106.
Transformation of the nitrogen cycle: recent trends, questions, and potential solutions 总被引:12,自引:0,他引:12
Galloway JN Townsend AR Erisman JW Bekunda M Cai Z Freney JR Martinelli LA Seitzinger SP Sutton MA 《Science (New York, N.Y.)》2008,320(5878):889-892
Humans continue to transform the global nitrogen cycle at a record pace, reflecting an increased combustion of fossil fuels, growing demand for nitrogen in agriculture and industry, and pervasive inefficiencies in its use. Much anthropogenic nitrogen is lost to air, water, and land to cause a cascade of environmental and human health problems. Simultaneously, food production in some parts of the world is nitrogen-deficient, highlighting inequities in the distribution of nitrogen-containing fertilizers. Optimizing the need for a key human resource while minimizing its negative consequences requires an integrated interdisciplinary approach and the development of strategies to decrease nitrogen-containing waste. 相似文献
107.
BACKGROUND
Multicopters are used for releasing particulates seeds, fertilizer and spray. Their low cost and high manoeuvrability make them attractive for spraying in steep terrain and areas where overspray is undesirable. This article describes a model of multicopter wake and its influence on particulate dispersion, which is computationally economical compared to many computational fluid dynamics (CFD) approaches, yet retains reasonable accuracy.RESULTS
A model was successfully implemented in OpenFOAM . It features source terms for the rotor wash, Lagrangian particle tracking, an evaporation model, and a porous medium approach to model the effect of the ground vegetation. Predictions were validated against the field tests of Richardson et al. which used a DJI Agras MG-1 multicopter in three different flights with airspeeds of 3.2–4.9 m s−1, ground speeds of 2.1–2.9 m s−1 and cross-wind speeds of 0.04–2.2 m s−1. The effective swath width (30% line separation) was predicted to within one standard deviation. Sensitivity to a rotor rotational speed, flight height, flight velocity, multicopter roll and yaw angles, surface roughness length, plant height and leaf density was checked.CONCLUSION
In all flight trials, the modelled swath was closest to the experimentally obtained swath when the surface roughness of the fetch was equal to 0.5 m (bushes) and the rotational speed of all rotors was equal to 2475 rpm with 0.75R (0.2 m) tall plant canopy (grass) introduced to the model. The model showed acceptable validity for flight velocities of ≤2.8–5 m s−1 when flight parameters can be approximately estimated. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献108.
Derek W. Gammon Mark A. Brown John E. Casida 《Pesticide biochemistry and physiology》1981,15(2):181-191
Pyrethroids are divided into two classes (Types I and II) based on their effects on the cercal sensory nerves recorded in vivo and in vitro and on the symptomology they produce in dosed cockroaches, Periplaneta americana. Type I compounds include pyrethrins, S-bioallethrin, [1R,cis]resmethrin, kadethrin, the 1R,trans and 1R,cis isomers of tetramethrin, phenothrin, and permethrin, and an oxime O-phenoxybenzyl ether. Electrophysiological recordings from dosed individuals reveal trains of cercal sensory spikes and sometimes also spike trains from the cercal motor nerves and in the CNS. Low concentrations of these pyrethroids act in vitro to induce repetitive firing in a cercal sensory nerve following a single electrical stimulus. This in vitro measurement, standardized for evaluating structure-activity relationships, shows that only 1R, insecticidal isomers are highly effective neurotoxins. The most potent compounds on the isolated nerve are [1R,trans]- and [1R,cis]tetramethrin, each active at 3 × 10?13M. The poisoning symptoms of Type I compounds are restlessness, incoordination, hyperactivity, prostration, and paralysis. Type II compounds include [1R,cis,αS]- and [1R,trans,αS]cypermethrin, deltamethrin, and [S,S]fenvalerate. These α-cyanophenoxybenzyl pyrethroids do not induce repetitive firing in the cercal sensory nerves either in vivo or in vitro; moreover, they cause different symptoms, including a pronounced convulsive phase. Two other pyrethroids with an α-cyano substituent, i.e., fenpropathrin and an oxime O-α-cyanophenoxybenzyl ether, are classified as Type I based on their action on a cercal sensory nerve but the symptoms with these compounds resemble Type II. The two classes of pyrethroid action evident with the cockroach are discussed relative to their neurophysiological effects and symptomology in other organisms. 相似文献
109.
Serologic and fecal markers to predict response to induction therapy in dogs with idiopathic inflammatory bowel disease
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110.
Falush D Wirth T Linz B Pritchard JK Stephens M Kidd M Blaser MJ Graham DY Vacher S Perez-Perez GI Yamaoka Y Mégraud F Otto K Reichard U Katzowitsch E Wang X Achtman M Suerbaum S 《Science (New York, N.Y.)》2003,299(5612):1582-1585
Helicobacter pylori, a chronic gastric pathogen of human beings, can be divided into seven populations and subpopulations with distinct geographical distributions. These modern populations derive their gene pools from ancestral populations that arose in Africa, Central Asia, and East Asia. Subsequent spread can be attributed to human migratory fluxes such as the prehistoric colonization of Polynesia and the Americas, the neolithic introduction of farming to Europe, the Bantu expansion within Africa, and the slave trade. 相似文献