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991.
Esophagoscopy.     
Esophageal pathology is one of the areas that had the major benefits from the advent of endoscopy. Esophagoscopy is a highly reliable diagnostic method for evaluating esophageal disorders that affect the mucosa or alter the lumen of the organ, such as foreign bodies, esophagitis, reflux disease, strictures, ulcers, fistula, and neoplasia. With endoscopy, the treatment of esophageal disorders has greatly improved as well, with the retrieval of foreign bodies and the dilation of esophageal strictures under direct visualization the main therapeutic indications.  相似文献   
992.
We report the results of clinical and microbiological investigations on Listeria monocytogenes infections in a flock of 55 sheep and describe the implications for the safety of the raw milk and raw-milk cheeses produced in the on-farm dairy. The outbreak was caused by feeding grass silage, which was contaminated with 5 log10 CFU L. monocytogenes/g. Clinically, although having been fed from the same batch of silage, abortive (nine ewes), encephalitic (one ewe) and septicaemic (four ewes) forms of listeriosis were observed during the outbreak phase. As the starting point of feeding the contaminated silage was known we could calculate an incubation period of 18+/-2 and 26 days for the abortive and the encephalitic form of listeriosis, respectively. Pathologically, the septicaemic cases suffered from Listeria accumulation at comparable numbers in visceral organs but not in the brain. Only a single ewe developed central nervous symptoms and a rhomb-encephalitis was immunohistologically confirmed. In this case the infection proceeded from the nasal mucosa into the brain, with no infections of the liver, spleen and other visceral organs. Sampling of the cheese production chain, the farm environment and the persons living at the farm revealed the exposure of a farm-worker to an isolate genetically indistinguishable from the outbreak clone, obviously through the consumption of faecally contaminated bovine raw milk. The cheese under processing was free of Listeria because, as a result of intensive consultations, the farmer ensured a proper acidification of the cheese. The epidemiological findings suggest that food safety matters should be assessed in any case where infection of food-producing animals with potential human pathogens is observed.  相似文献   
993.
A surgically induced model of arterial thrombosis in pigs (60–80 kg live weight) has been developed using a balloon angioplasty technique. The purpose of this model is to assess the thrombogenicity of milkfat in comparison with other dietary lipids, thereby assessing its importance in the pathogenesis of human coronary heart disease. Balloon angioplasty catheters (Meditech, 3 cm X 8 mm balloon) are inserted into the left and right femoral arteries via a cut-down on to the saphenous artery. The balloons are inflated five times for 30 seconds with 30 second intervals between inflations. This results in endothelial denudation, exposure of sub-endothelial connective tissue and formation of platelet rich thrombi. Thrombus size is quantitated using autologous blood platelets labelled with 99Tc-HMPA0 (technetium - “Deretec”).  相似文献   
994.
Reasons for performing the study: Removal of large chip fractures of the carpal bones and the osteochondral deficits that result, have been associated with a worse prognosis than removal of small fragments in similar locations. Hypothesis: Reducing the articular defects by repair of large osteochondral fragments may have advantages over removal. Methods: Horses with osteochondral chip fractures that were of sufficient size and infrastructure to be repaired with small (2.7 mm diameter) AO/ASIF cortex screws were identified and repair effected by arthroscopically guided internal fixation. Results: Thirty‐three horses underwent surgery to repair 35 fractures of the dorsodistal radial carpal bone (n = 25), the dorsal margin of the radial facet of the third carpal bone (n = 9) and the intermediate facet of the distal radius (n = 1). There were no surgical complications and fractures healed satisfactorily in 26 of 28 horses and 23 horses returned to racing performance. Conclusion: Arthroscopically guided repair of carpal chip fractures with small diameter cortex screws is technically feasible and experiences with 33 cases suggest that this may have advantages over fragment removal in managing such cases. Potential relevance: Surgeons treating horses with large chip fractures of the carpal bones should consider arthroscopically guided internal fixation as an alternative to removal.  相似文献   
995.
996.
导读:虾料配制时首先考虑的因子。 前言 凡纳滨对虾原产于美洲中南部的太平洋沿岸,我国于1988年引进,由于该虾生长快、适应性强、食性广、价格高、抗病力强等优点,迅速成为主要养殖品种。当前,饲料成本占总养殖成本的50~60%,而蛋白水平又是影响生长性能和饲料成本的主要因素。那么怎样才能降低饲料成本呢?通过优化蛋白能量和非蛋白能量在饲料中的比例,可以达到这一目的。如果蛋白相对于能量过量,那么,  相似文献   
997.
Testing all the cattle in an entire state with a uniform procedure for each animal affords an opportunity to relate human injury data to a known number of animals handled while carrying out a standardized procedure. Our objective was to describe the type and incidence density of injuries associated with TB-testing a large number of cattle herds, and to delineate the various factors associated with the risk of injury. A survey was mailed to all veterinarians (N = 259) who had completed at least five official bovine TB (bTB) herd tests in Michigan in 2001. We collected data regarding basic demographics and health status, work experience, veterinary specialty, and practice information. Each veterinarian was also requested to complete a separate injury questionnaire for each injury received while TB testing livestock in 2001. Accurate addresses were found for 247 eligible veterinarians, 175 (71%) of whom returned the survey. Thirty-six veterinarians reported a total of 53 injuries (10 major, 12 minor and 31 self-treated). Hands (29%) and legs (21%) were the anatomic locations most frequently injured, with sprains/strains (30%) and abrasion/contusion (30%) the most common types of injuries sustained. The overall incidence density of injuries was 1.9 per 10,000 animals tested. Female gender (RR = 3.3), being employed by the government (RR = 4.5), and smoking (RR = 6.0) were significantly associated with a higher rate of injury. Significant colliniearities were found between some risk factors associated with an increased rate of injury and participants thought 81% of their injuries could have been prevented. These results are explained by the administrative structure of the bTB testing program in Michigan, and the changing demographics of the veterinary workforce.  相似文献   
998.
999.
The development of methods to produce embryos in vitro in the horse has been delayed compared with other domestic species. Oocytes can be collected from excised ovaries or from the small or preovulatory follicles of live mares. Intracytoplasmic sperm injection is the only reliable method to fertilize equine oocytes in vitro. Intracytoplasmic sperm injection-produced embryos can be transferred into the oviducts of recipient mares or cultured to the morula or blastocyst stage of development for nonsurgical embryo transfers into recipients' uteri. Embryos cultured in vitro have some morphological differences compared with embryos collected from the mares' uteri. Most notably, the embryonic capsule does not form in culture, and the zona pellucida fails to expand completely. However, embryo produced in vitro can result in viable pregnancies and healthy offspring.  相似文献   
1000.
The results of a series of experiments to investigate the use of the arylmethane dye, malachite green, for the control of proliferative kidney disease in rainbow trout (Salmo gairdneri Richardson) are described. Under field conditions using the bath application method the dye gave good control of the disease with treatments at 1.6 ppm for 40 minutes repeated at seven, 14 and 21 day intervals. Flush treatments were also successful using the same treatment intervals and beginning with 3.2 ppm malachite green. The problems of toxicity and of standardising the exposure of the fish to the dye with flush treatments are discussed.  相似文献   
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