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1.
SUMMARY The surgical correction of facial deformities of the horse have rarely been undertaken. The surgical and medical management of submucous clefting of the anterior maxilla in a young colt is described.  相似文献   
2.
Computed tomography-dacryocystography (CT-DCG) was used to evaluate the nasolacrimal system in four patients (three dogs and one horse) that were admitted for evaluation of chronic epiphora, facial swelling, or facial trauma. The four patients are reviewed and the technique for performing CT-DCG is described. Additionally, the indications for this procedure are discussed. CT-DCG is advantageous because cross-sectional imaging provides superior resolution of the nasolacrimal apparatus and the relatively long, small-diameter, bony nasolacrimal canal in most veterinary patients.  相似文献   
3.
Cinmethylin (SD 95481), is a novel herbicide developed for the selective pre-emergence control of many annual grass weeds in a wide range of temperate and tropical crops. Representing new herbicide chemistry, cinmethylin is in the cineole family. Cinmethylin is a mobile colourless liquid with a boiling point of 313°C under an inert atmosphere at atmospheric pressure. It has a density of 1015 kg m?3 and a viscosity of 70–90 mPa s, both at 20°C. It is miscible in all proportions with most organic solvents but has a low solubility, 63 mg litre?1, in water. It has a vapour pressure of 10.2 mPa (20°C) and the vapour pressure/temperature relationship is given by loge P(Pa)=28.9–9816/T (K). The n-octanol/water partition coefficient is 6850 and soil organic matter/water sorption coefficient (Kom) ranges between 165 and 235 over the three types of soil used in these studies. Cinmethylin is stable in water over the pH range 3–11. Solutions of cinmethylin in water or solvents are reasonably stable to sunlight, though thin films on a quartz surface photooxidise mainly to an ester within 24 h. This rate can be reduced by the addition of photostabilisers or by sorption onto soil surfaces. In an inert atmosphere cinmethylin is stable to high temperatures, though, in air, oxidation occurs at temperatures above 100°C to give the same product as by photodecay.  相似文献   
4.
A mail-out survey questionnaire was developed by the Agroforestry group at the University of Guelph to determine the level of awareness and interest in the adoption of agroforestry systems by landusers from four townships in Wellington County, Ontario. The questionnaire investigated: (1) the current level of knowledge regarding windbreaks, woodlots and plantations, intereropping, riparian plantations and silvipasture, (2) the present level of participation in each of these systems on-farm, (3) the perceived benefits and/or drawbacks of each of these initiatives with respect to total farm income, income diversity, land rehabilitation, land value/equity, soil/water conservation, labour intensity, overhead and return on the term of investment.The majority of respondents were familiar with conventional agroforestry systems such as windbreaks and woodlots/plantations (80%, 62% respectively), therefore the level of interest in the adoption of these practices was significant (74%, 66% respectively). Response rates were lower for silvipasture, riparian plantations and intercropping, most likely as result of the low level of familiarity with these practices (20%, 32%, 4% respectively). Respondents commented that agroforestry systems would have a neutral effect on farm income, and would increase land stewardship. In some cases, interested landusers indicated a willingness to participate in agroforestry systems even though they anticipated increases in overhead and labour intensity; however, this was only true if they held land stewardship as a priority. Landusers were more concerned with the economic aspects of agroforestry, as a determinant to the future adoptability of particular practices. Age, gender, farm operation and farm size were not correlated with the adoption of agroforestry systems.The success of agroforestry programs on farms in the study area is largely dependent on the attitudes and willingness of landusers to participate in non-traditional agricultural systems.  相似文献   
5.
Elbow dysplasia is a heritable disease that is a common cause of lameness and progressive elbow osteoarthritis in young large breed dogs. The Orthopedic Foundation for Animals (OFA) screens elbow radiographs, and assigns grades 0–3 based on presence and severity of bony proliferation on the anconeal process. Grade 1 is assigned when less than 3 mm is present and considered positive for dysplasia. We investigated the incidence of elbow dysplasia and progression of osteoarthritis in elbows with grades 0 and 1 in 46 elbows screened at least 1 year previously, using CT as a gold standard and with the addition of CT absorptiometry. The incidence of dysplasia based on CT was 62% in grade 0, and 75% in grade 1 elbows, all of which had medial coronoid disease. Progressive osteoarthritis at recheck was consistent with elbow dysplasia. The sensitivity and specificity of the OFA grade for elbow dysplasia compared to CT findings was 75% and 38%, respectively. Increased bone mineral density of the medial coronoid process as characterized by osteoabsorptiometry warrants further investigation with respect to elbow dysplasia. Proliferation on the anconeal process without CT evidence of dysplasia or osteoarthritis was present in 20% of the elbows, and is theorized to be an anatomic variant or enthesopathy of the olecranon ligament/synovium. Results of our study suggest that the “anconeal bump” used for elbow screening by the OFA is a relatively insensitive characteristic, and support the use of CT for identifying additional characteristics of elbow dysplasia.  相似文献   
6.
7.
R J Paul  M Bauer  W Pease 《Science (New York, N.Y.)》1979,206(4425):1414-1416
Under aerobic conditions, glucose is primarily catabolized by vascular smooth muscle to lactate, in spite of an adequate oxidative capacity. Although this is often considered to be indicative of some nonspecific metabolic insufficiency, there is evidence that aerobic glycolysis is specifically coupled to sodium and potassium transport processes, whereas oxidative metabolism is couple to contracticle energy requirements.  相似文献   
8.
DNA translocases are molecular motors that move rapidly along DNA using adenosine triphosphate as the source of energy. We directly observed the movement of purified FtsK, an Escherichia coli translocase, on single DNA molecules. The protein moves at 5 kilobases per second and against forces up to 60 piconewtons, and locally reverses direction without dissociation. On three natural substrates, independent of its initial binding position, FtsK efficiently translocates over long distances to the terminal region of the E. coli chromosome, as it does in vivo. Our results imply that FtsK is a bidirectional motor that changes direction in response to short, asymmetric directing DNA sequences.  相似文献   
9.
10.
AIM: To establish the prevalence of anthelmintic resistance in parasitic nematodes on sheep farms in New Zealand.

METHODS: A cross-sectional prevalence study was conducted, using a standardised faecal nematode egg count (FEC) reduction (FECR) test (FECRT) for ivermectin, at a full (0.2 mg/kg) and half (0.1 mg/kg) dose rate, and albendazole, levamisole and albendazole-levamisole in combination, on 60 lambs (n=10 per group) on farms selected from throughout New Zealand. Farms that conformed with selection criteria were chosen at random (n=80) or with a history of suspected resistance to macrocy- clic lactone (ML) anthelmintics (n=32). Resistance to an an- thelmintic was inferred when there was <95% reduction in FEC 7-10 days after treatment. Larval cultures were performed for all control groups and for treated groups for which resistance was evident.

RESULTS: Of the farms randomly selected, 36% showed ≥95% FECR for all anthelmintics tested; resistance to ivermectin at 0.1 and 0.2 mg/kg liveweight was evident on 36% and 25% of these farms, respectively. Resistance to both ivermectin (0.2 mg/kg) and levamisole was evident on 8/80 (10%) farms, to ivermectin and albendazole on 10/80 (13%) farms, and to iver- mectin, levamisole and albendazole on 6/80 (8%) farms. The prevalence of resistance to a half dose of ivermectin tended to be more prevalent on farms with a history of suspected ML resistance (p=0.06). Resistance to albendazole was seen across all the main parasite genera, and to levamisole in Nematodirus, Ostertagia (= Teladorsagia) and Trichostrongylus species. Resistance to ivermectin was dominated by Ostertagia spp, although Cooperia, Nematodirus and Trichostrongylus species were also implicated.

CONCLUSION: Anthelmintic resistance in parasitic nema-todes of sheep is common in New Zealand. Not only was resistance to albendazole and levamisole common, but resistance to the ML, ivermectin, was at a higher prevalence than expected. Sheep farmers and advisors in New Zealand need to re-evaluate the way they manage parasites, and more research is urgently needed if the steady decline in anthelmintic susceptibility is to be halted.  相似文献   
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