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971.
972.
973.
In an in vivo study, the rate of iodide oxidation by horseradish peroxidase was found to be reduced by the addition of ammonium thiocyanate to the system. The seleetive herbicidal activity of sodium iodide towards dwarf bean, pea, kale and cabbage was tested while the poicnlial ihioeyanale conteni of these platits was measured, A good relationship between inereasmg thiocyanale content and inereasing resistance to iodide was observed. 相似文献
974.
Campylobacter jejuni is a microorganism that only recently has been implicated in gastroenteritis in humans. As appropriate methods used for detection of the bacterium have been developed, the rates of illness caused by the pathogen were found to approach or surpass those attributed to Salmonella. Substantial evidence has been gathered to document that the route for human infection is through the ingestion of adulterated food and drink. Some slaughter animals harbor this potential pathogen among the intestinal flora and, consequently, transfer of the organism to carcasses and to the resulting meat products does occur. The most frequently implicated meat is poultry, with an incidence of recovery of C. jejuni from the store-bought poultry meat reported to be at least 50%. Red meat from slaughter animals have also yielded this bacterium from carcasses, but at lower incidence levels. Foodborne disease has been associated most frequently with the ingestion of raw milk, but poultry, hamburger, and other foods have all been implicated as potential sources. However, cause and effect relating the presence of C. jejuni in meat and human gastroenteritis has not been demonstrated. Additional research is needed to determine whether C. jejuni isolated from meat causes gastroenteritis and whether all strains of the organism are virulent. Recognition of C. jejuni as a potential meatborne pathogen by the meat industry is necessary, and appropriate sanitary practices to prevent passage of the organism through meat products should be implemented. 相似文献
975.
Distribution of immunoglobulin-bearing cells in the gut-associated lymphoid tissues of the turkey: effect of antibiotics 总被引:2,自引:0,他引:2
Distribution of immunoglobulin (Ig)-bearing cells in the gut-associated lymphoid tissues of antibiotic treated and untreated control turkeys (Meleagris gallopavo) was compared. Antibiotic treatment was similar to a regimen used in commercial turkey production, which included preincubation dipping of fertile eggs in gentamicin solution, injection of turkeys with gentamicin at hatching, and inclusion of chlortetracycline in the diet. Tissues were examined from turkeys at 3, 7, 14, and 21 days of age with a direct immunofluorescence procedure. Cell distribution in control turkeys was as follows: In the bursa of Fabricius, IgA-carrying cells predominated at 3 days of age, but at later intervals, the 3 classes of Ig-bearing cells were in equal numbers. In the cecal tonsils, IgM- and IgA-bearing cells were in larger numbers at 3 days of age, whereas, the IgG-bearing cells were sparsely distributed. By 7 days of age, IgM cells became more numerous in the cecal tonsils and remained numerous until 21 days of age. At 3 days of age, IgA cells predominated in the small intestines and IgM cells predominated in the large intestine. At 7 and 14 days of age, IgM cells were more numerous in the small and large intestines, but by 21 days of age, IgA cell population equaled that of IgM. The IgG cells were generally sparse in the intestines. Antibiotic treatment often resulted in lower numbers of Ig-positive cells, especially those bearing IgM and IgA. Normal development of the bursa of Fabricius was also retarded in this group. 相似文献
976.
Toxocara canis second stage larvae (L2) hatched in the stomach of mice and within 2 h reached all parts of the small intestine, the posterior half being the preferred site for larval penetration. Following penetration at the base of crypts of leiberkuhn they followed tortuous routes in the lamina propria, and entered the tunica muscularis obliquely. Larvae only appeared to be arrested in their migration in the submucosa and lamina propria by an inflammatory reaction composed mainly of lymphocytes and eosinophils. Larvae were seen entering and within lymphatic vessels as well as the peritoneal cavity and invasion of the vascular system followed though actual penetration of intestinal blood vessels was not seen. Proteolytic enzyme activity was detected in culture media in which L2 larvae were maintained. 相似文献
977.
Isolation and functional analysis of normal canine blood monocytes and resident alveolar macrophages 总被引:2,自引:0,他引:2
The percentage of mononuclear phagocytes bearing the Fc receptor for immunoglobulin G, the percentage of cells phagocytic for Candida albicans and latex particles, and the phagocytic index for blood monocytes and alveolar macrophages from healthy dogs are reported. Blood monocytes were concentrated by density-gradient centrifugation, whereas alveolar macrophages were obtained in high yield by bronchoalveolar lavage. Adherent populations of those cells were used for functional assays after repeated washing to remove nonadherent cells. A greater percentage of adherent alveolar macrophages than adherent blood monocytes showed evidence of the Fc receptor for immunoglobulin G. Similarly, adherent alveolar macrophages showed significantly greater phagocytic ability, as measured by percent phagocytic cells and phagocytic index, using C albicans and latex particles, than did adherent canine blood monocytes. 相似文献
978.
979.
Infection studies in kittens, using feline infectious peritonitis virus propagated in cell culture 总被引:4,自引:0,他引:4
The propagation of feline infectious peritonitis virus (NW1-FIPV strain) in cell culture is described. Tissue culture-propagated virus was used to inoculate specific-pathogen-free kittens intraperitoneally, intratracheally, or orally. Intraperitoneal inoculation caused seroconversion and effusive peritonitis in 100% of the kittens. Intratracheal inoculation produced disease in 60% of the kittens, and oral inoculation in only 20%. Seroconversions without production of disease occurred in 10% of the kittens inoculated by either the intratracheal or the oral route. The remainder of the kittens inoculated by the intratracheal (30%) and oral (70%) routes did not develop serum antibodies or disease. 相似文献
980.