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991.
U P Kalkofen 《Veterinary Clinics of North America: Small Animal Practice》1987,17(6):1341-1354
Hookworms are probably the most faithful intestinal parasites of dogs and cats. Infecting all ages, they are life-threatening to the very young and potentially so to the fully mature hookworm-resistant host. Discussed in this article are the diagnosis of hookworm infection, the life cycle of hookworms, the cutaneous and intestinal manifestations of hookworm infection and disease, and the treatment and prevention of infection. 相似文献
992.
993.
Moser I Prodinger WM Hotzel H Greenwald R Lyashchenko KP Bakker D Gomis D Seidler T Ellenberger C Hetzel U Wuennemann K Moisson P 《Veterinary microbiology》2008,127(3-4):399-406
Tuberculosis infections caused by Mycobacterium (M.) pinnipedii in a South American sea lion, Bactrian camel, and Malayan tapirs kept in two zoological gardens spanning a time period of 5 years are reported. The zoos were linked by the transfer of one tapir. Conventional bacteriological and molecular methods were applied to detect the pathogen. Spoligotyping and MIRU/VNTR-typing performed to assess the genetic similarity revealed identical molecular characteristics of the isolates from all animals involved. Anti-tuberculosis antibodies were detected using ELISA and a recently developed serological rapid test. The study shows that: (i) using molecular methods, the assessment of the genetic relationship of infectious agents helps to confirm the routes of infection, and that (ii) immunological tests may help to detect tuberculosis infections ante mortem more reliably and early. This would prevent the transfer of tuberculosis by asymptomatic animals. 相似文献
994.
Detection of virulent strains of Streptococcus suis type 2 and highly virulent strains of Streptococcus suis type 1 in tonsillar specimens of pigs by PCR. 总被引:17,自引:0,他引:17
H J Wisselink F H Reek U Vecht N Stockhofe-Zurwieden M A Smits H E Smith 《Veterinary microbiology》1999,67(2):143-157
We developed a PCR assay for the rapid and sensitive detection of virulent Streptococcus suis type 2 and highly virulent S. suis type 1 in tonsillar specimens from pigs. The PCR primers were based on the sequence of the gene encoding the EF-protein of virulent S. suis type 2 strains (MRP+EF+) and highly virulent S. suis type 1 strains (MRP(s)EF+) and of the EF protein of weakly virulent S. suis type 2 strains (MRP+EF). The latter strains give rise to larger PCR products than the virulent strains of S. suis type 1 and 2. A positive control template was included in the assay to identify false negative results. The PCR was evaluated using tonsillar specimens from herds known (or suspected) to be infected and herds without an S. suis history. The results obtained with the PCR assay were compared with the results obtained with a newly developed bacteriological examination. In this bacteriological examination we were able to identify the EF-positive strains directly in the tonsillar specimens. From the 99 tonsils examined, 48 were positive in the PCR and 51 negative. All specimens from which EF-positive S. suis strains were isolated were also positive in the PCR assay. Three samples were positive in the PCR, but negative by bacteriological examination. The results demonstrated that the PCR is a highly specific and sensitive diagnostic tool for the detection of pigs carrying virulent strains of S. suis type 2 and highly virulent strains of type 1. Application of the assay may contribute to the control of S. suis infections. 相似文献
995.
996.
Protein-DNA interactions in vivo upstream of a cell cycle-regulated human H4 histone gene 总被引:23,自引:0,他引:23
Cell cycle-dependent histone genes are transcribed at a basal level throughout the cell cycle, with a three- to fivefold increase during early S phase. Protein-DNA interactions in the 5' promoter region of a cell cycle-regulated human H4 histone gene have been analyzed at single-nucleotide resolution in vivo. This region contains two sites, with four potential protein-binding domains, at which the DNA is protected from reaction with dimethyl sulfate in cells and from digestion with deoxyribonuclease I in nuclei. These protein-DNA interactions persist during all phases of the cell cycle and dissociate with 0.16 to 0.2M sodium chloride. 相似文献
997.
U Johannsen 《Archiv fuer experimentelle veterinaermedizin》1973,27(3):449-479
998.
Bartels T Krautwald-Junghanns ME Portmann S Gille U Brinkmeier J Kummerfeld N 《Veterinary pathology》2002,39(3):396-399
Four birds in a flock of 125 purebred Crested ducks (Anas platyrhynchos f. dom.) had cerebellar signs of unknown etiology. They had radiographically evident perforations of various sizes in the parieto-occipital calvaria. Gross necropsy of euthanatized ducks revealed yellow intracranial masses in the brain of each. Histologically, these masses were intracranial lipomas consisting of univacuolated fatty tissue separated into lobules by strands of connective tissue. The masses had caused serious deformation of the rostral part of the cerebellum, leading to a nearly complete flattening of cerebellar folia, and were interpreted as the cause for the central nervous clinical signs observed. These intracranial lipomas were similar to those previously reported in other animals and humans. 相似文献
999.
1000.