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11.
To estimate the prevalence and distribution of Salmonella in the chain from cattle to the consumer, faeces, mesenteric lymphnodes and beef cuts from 235 cattle, stool samples from 300 workers of the same Addis Ababa abattoir, and 330 minced beef samples from supermarkets in Addis Ababa were analyzed. Isolated Salmonella strains were serotyped and tested for antibiotic susceptibility. Low prevalence in faeces and lymphnodes, and higher contamination rates of beef cuts (diaphragm, abdominal muscles) indicate severe cross-contamination during slaughter. Animals of poor health status were far more frequently carriers of salmonellae, which stresses the need of intensive ante-mortem inspection on slaughter animals. During transport from slaughterhouse to the supermarkets, production and selling of minced beef, the prevalence of Salmonella did not increase.  相似文献   
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Three-dimensional (3D)/four-dimensional (4D) volume ultrasound is an established method in human medicine that offers various options for analysing and presenting ultrasound volume data. However, the successful application of the different 3D/4D imaging modalities in pregnant dogs and cats has not yet been reported in the literature. The main reasons for this are: (1) the high costs of 3D/4D ultrasound systems, (2) operation difficulties due to high breathing frequency in non-sedated animals and (3) the missing specific knowledge in veterinary medicine concerning how to perform high-quality volume scans. Automatically acquired ultrasound volume data sets were generated with two different ultrasound systems: the portable Voluson i and the stationary Voluson Expert 730. Different 3D/4D imaging modalities were tested in regard of their practicability in pregnancy monitoring in dogs and cats. Nine different volume imaging modalities were applied using the saved files. For the presentation of the static 3D volume data sets, we used the multiplanar, niche, surface, transparency, glass body, inversion, volume calculation and tomographic ultrasound imaging modes. For the dynamic 4D data, the surface and glass body modes were applied. By changing the human standard settings to the requirements of small animal anatomy, it was found that 3D/4D ultrasound has great potential for the characterization of pregnancy in queens and bitches. The 3D/4D technology offered advanced information about pregnancy status and birth prediction and improved the diagnostic confidence. By using standardized examination protocols, 3D/4D ultrasound will allow a reduction in examination time by generating even more relevant information. These benefits, combined with possible future cost reduction of commercial ultrasound systems, might lead to frequent utilization in routine pregnancy diagnostic and birth management in small animal practice.  相似文献   
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Laser-cooled 9Be+ ions confined in two-dimensionally extended lattice planes were directly observed, and the images were used to characterize the structural phases of the ions. Five different stable crystalline phases were observed, and the energetically favored structure could be sensitively tuned by changing the areal density of the confined ions. The experimental results are in good agreement with theoretical predictions for the planar (infinite in two dimensions) one-component plasma. Qualitatively similar structural phase transitions occur, or are predicted to occur, in other experimentally realizable planar systems.  相似文献   
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During the five year period from early 1982 to 1986, we engaged in research concerning the chlorinated hydrocarbon content of eels (Anguilla anguilla L.) in the limnic water ecosystem of Berlin (West). The total count of analytical samples, taken at 11 different sampling points, comprised 370 samples, divided up into 41 collectives. Each fish was checked individually for the patterns of contamination with chlorinated hydrocarbons, especially DDT-, BHC-, and PCB-related compounds. The various areas of the Berlin water system develop different particularities as regards pollution. The northern part, consisting mainly of the Tegeler See and the Niederneuendorfer See above the Spree river junction, is in near-neutral condition as shown by rather low levels of chlorinated hydrocarbons in the eels. The Teltowkanal, as it is heavily affected by industrial and urban wastewater, shows considerable contamination of its fish population. Main pollutants are the BHC-isomers, including delta-BHC and the DDT-metabolites 4.4-DDD and 4.4-DDE, as well as higher and lower chlorinated biphenyls (PCB). The lower part of the Havel river, a lake system represented in this study by the fishing stations St?ssensee, Pichelsdorfer Gemünd, Schwanenwerder and Pfaueninsel, is limnologically a changing zone characterized by the influx of Spree and Havel rivers and in part by the Teltowkanal, which is reflected in the composition of the organochlorine contamination as well. Three main fishing stations were chosen to represent typical conditions of the ecosystem (Niederneuendorfer See, Pfaueninsel, Teltowkanal) and the trends of concentration of organochlorines in eels were monitored.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A 1-year-old, female spayed domestic shorthair cat was presented with a 4-week history of dysphagia and regurgitation soon after oral treatment with clindamycin. Fluoroscopic and endoscopic examinations confirmed the presence of a single cervical oesophageal stricture 4 cm caudal to the pharynx. A fluoroscopically and endoscopically guided balloon dilation was performed six times consecutively over a period of 3 weeks as reformation of the stricture appeared within 3-7 days. Feeding via percutaneous endoscopic gastrostomy-tube as long-term management of the condition was declined by the owner. A self-expanding metal oesophageal stent with the following dimension was subsequently implanted: fully open diameter 16 mm, length 30 mm. After stent implantation, the cat was fed on mashed canned food and did not show any clinical signs for 12 months. Twelve months post-implantation the cat was no longer able to eat even liquid food, became lethargic and the owner opted for euthanasia. On post-mortem examination the stent surfaces were overgrown by oesophageal mucosa by approximately 50%. Stent obstruction was detected and caused by swallowed hair which also seemed to have hampered mucosal integration in the distal part of the stent.  相似文献   
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Flow cytometric sexing of spermatozoa followed by application in artificial insemination or in vitro fertilization provides a unique opportunity to predetermine the sex of offspring and might enhance the conservation management of endangered species in captivity such as the elephant and rhinoceros. To obtain an indication of the sortability of spermatozoa from these species, the relative DNA differences between X and Y chromosome bearing spermatozoa (fresh, frozen thawed, epididymal) from three rhinoceros species [white ( Ceratotherium simum ), black ( Diceros bicornis ), Indian ( Rhinoceros unicornis )] and both elephant species, the Asian and the African elephant ( Elephas maximus, Loxodonta Africana ), were determined through separation of spermatozoa into X and Y chromosome bearing populations, using a modified high speed flow cytometer. The head profile areas of spermatozoa from all five species were measured using light microscopy. By multiplying the relative DNA differences and the head profile areas, the sperm sorting indices were calculated to be 47, 48 and 51 for white, black and Indian rhinoceros respectively. The calculated sorting index for the Asian elephant was 66. In the African elephant, we determined the highest sorting index of 76. These results indicate the practicability of flow cytometric sex sorting of spermatozoa from the tested rhinoceros species and both elephant species. The lower sorting indices in rhinos indicate that sex sorting of spermatozoa from the rhinoceros will be more challenging than in elephants.  相似文献   
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