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51.
A 14-year-old female cougar died from gastroduodenal adenocarcinomas and rectal adenoma. At necropsy, polypoid tumor masses of various sizes were scattered on the mucosal surfaces of the stomach, duodenum, and rectum. Histologically, the gastric tumor was diagnosed as an intestinal type adenocarcinoma and the tumor cells metastasized to the mesenteric lymph nodes, spleen, and lung. Helicobacter-like organisms were detected in the lumina lined by foveolar epithelium. In the duodenum, the carcinoma cells were localized in the limina propria and many of them were intensely positive for proliferating cell nuclear antigen (PCNA). In contrast, the rectal adenoma had a lower number of PCNA-positive cells. In the rectum, chronic inflammation with numerous spirochetes was also noted. These results indicated that the occurrence of the gastrointestinal tumors might be associated with the bacterial infection described above.  相似文献   
52.
In 1996 and 1997, the seroprevalence against Leptospira in parturient sows with premature birth or stillbirth from two herds was investigated. In three out of four sow serum samples obtained in Gunma Prefecture, the antibody titers to Leptospira interrogans serovar copenhageni (M20) were higher than 10,000 (the reciprocal of the serum dilution). Furthermore, the antibody titers to L. interrogans serovar canicola (Hond Utrecht IV) were significantly high in the three sows and the titers ranged from 1,000 to 3,000. In sows obtained in Chiba Prefecture, significantly high antibody titers to serovar copenhageni (M20) were confirmed in eight out of 40 sows, and antibody titers greater than 10,000 in six of them. Significantly high antibody titers to L. interrogans serovar icterohaemorrhagiae (RGA) and L. canicola (Hond Utrecht IV) were confirmed in four and 18 out of the 40 sows, respectively, compared with the titers to the other serovars. These findings may indicate the prevalence of leptospirosis in pig herds in both Gunma and Chiba Prefectures.  相似文献   
53.
Formalinized Aeromonas (A.) hydrophila agglutinated loosely with the formalinized American channel catfish erythrocytes (FACCE), while live A. hydrophila agglutinated tightly with the FACCE. There was a significant difference on the number of attaching bacterial cells to the FACCE (p<0.01) (n=40 erythrocytes) between formalinized and live A. hydrophila. The other bacteria such as Salmonella (S.) Typhimurium ST-5, Escherichia (E.) coli V-517 and Staphylococcus (S.) hyicus ATCC1249 used in this experiment did not attach the FACCE.  相似文献   
54.
The abilities of Salmonella serovars to colonize the reproductive organs of chickens and to contaminate eggs were compared. Mature laying hens were inoculated intravenously with 10(5) colony-forming units of Salmonella enteritidis, Salmonella typhimurium, Salmonella infantis, Salmonella hadar, Salmonella heidelberg, or Salmonella montevideo to cause the systemic infection. Salmonella enteritidis was recovered from three yolks of the laid eggs (7.0%), suggesting egg contamination from the transovarian transmission of S. enteritidis. The liver, spleen, and cecum were colonized by each serovar similarly at 4 or 7 days postinoculation (PI), whereas the ovary and preovulatory follicles were colonized by S. enteritidis with significantly (P < 0.05) higher levels than by the other serovars at 4 and 7 days PI. Salmonella enteritidis was recovered from the cloaca and vagina at 2, 4, and 7 days PI and from the other portions of the oviduct at 4 and 7 days PI. In addition, S. enteritidis had been persistent in the peripheral blood for 7 days PI. These results suggest that S. enteritidis is the predominant serovar to colonize the reproductive organs of mature laying hens among six serovars used in this study, reflecting the field situatibn in which the predominant outbreaks of human salmonellosis were caused by S. enteritidis-contaminated eggs recently. The ability of S. enteritidis to colonize the reproductive organs may be one of the reasons that egg contamination with S. enteritidis has increased.  相似文献   
55.
The feces, colonic contents, and colonic mucosa from two beagles and a mongrel with and without mucohemorrhagic diarrhea were anaerobically cultured and after 72 hr, lucent and rough colonies with weak beta-hemolysis were observed. Small spirochetes with one or two loose waves in the colonies were observed under a phase contrast microscope and the spirochete cells sometimes aggregated. The 16SrDNA sequencing results demonstrated that the canine isolates were B. pilosicoli and the base alignments registered in DDBJ. This is the first report concerning the isolation of B. pilosicoli from dogs in Japan.  相似文献   
56.
Microorganisms from 45 jungle crows (Corvus macrorhynchos) captured from July to December 2002 at Ueno Zoo, Tokyo were identified as Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Enterobacter agglomerans, Pseudomonas maltophila, Staphylococcus spp., Micrococcus spp., and Streptococcus spp. E. coli showed the highest rate of isolation (21.6%). In an in vitro susceptibility test for 29 isolates of E. coli to 14 antimicrobial agents, all the isolates were resistant to penicillin G, vancomycin, erythromycin, lincomycin, bicozamycin, sulfadimethoxine, and olaquindox. Several isolates of them were also resistant to tetracycline, oxytetracycline, streptomycin, chloramphenicol, and ampicillin. Twenty-nine isolates were divided into 19 serogroups and the most frequently identified serogroups were O8, O114 and O144, which showed the same multidrug-resistant patterns.  相似文献   
57.
Salmonella enteritidis (SE)-induced changes in various T and B lymphocyte subpopulations in the cecal tonsils of chickens were analyzed using flow cytometry. At 1 day post-SE inoculation, the percentages of CD3(+) and CD8(+) T lymphocytes were significantly decreased in the group inoculated with 1x10(9) SE colony-forming units (CFU) (SE high) and in the group inoculated with 1x10(6) SE CFU (SE low) compared with the uninfected control group. The percentage of CD4(+) T lymphocytes was significantly increased in the SE high group compared to the uninfected and the SE low groups at 4 days after SE inoculation. The percentage of IgG(+) B lymphocytes was also significantly increased in both SE high and low groups compared to the uninfected control at 6 days post-SE inoculation. In contrast, the SE low group showed significantly fewer IgM(+) B lymphocytes compared to the uninfected and SE high groups. These results show that SE infection induces significant changes in the cecal tonsil lymphocytes subpopulations shortly following SE inoculation.  相似文献   
58.
Feral raccoons (Procyon lotor) have been growing in number in Japan, and they are becoming a problematic invasive species. Consequently, they are commonly captured and killed in pest control programs. For effective population control of feral raccoons, it is necessary to understand their reproductive physiology and ecology. Although the reproductive traits of female raccoons are well known, those of the males are not well understood because specialized knowledge and facilities are required to study them. In this study, we first used a simple evaluation method to assess spermatogenesis and presence of spermatozoa in the tail of the epididymis of feral male raccoons by histologically examining the testis and epididymis. We then evaluated the possibility of using 7 variables—body weight, body length, body mass index, testicular weight, epididymal weight, testicular size and gonadosomatic index (GSI)—to estimate spermatogenesis and presence of spermatozoa in the tail of the epididymis. GSI and body weight were chosen as criteria for spermatogenesis, and GSI was chosen as the criterion for presence of spermatozoa in the tail of the epididymis. Because GSI is calculated from body weight and testicular weight, this model should be able to be used to estimate the reproductive state of male raccoons regardless of season and age when just these two parameters are known. In this study, GSI was demonstrated to be an index of reproductive state in male raccoons. To our knowledge, this is the first report of such a use for GSI in a member of the Carnivora.  相似文献   
59.
OBJECTIVE: Adequate fruit and vegetable intake has been suggested to protect against colorectal cancer. However, several recent prospective studies have reported no association. We therefore examined the association between fruit and vegetable intakes and the risk of colorectal cancer in a prospective cohort study in Japan. DESIGN: Between June and August 1990, 47 605 Japanese men and women completed a self-administered questionnaire, including a food-frequency questionnaire. We divided the subjects into quartiles based on their self-reported fruit and vegetable consumption. There were 165 colon cancer and 110 rectal cancer incidences identified during 7 years of follow-up, to the end of December 1997. We used Cox proportional hazards models to estimate the relative risk (RR) of developing colorectal cancer according to the level of fruit and vegetable consumption, applying adjustments for potential confounders. RESULTS: No statistically significant association was observed between fruit and vegetable consumption and the risk of colorectal cancer. The multivariate RR of colon cancer in the highest quartile of fruit and vegetable intake compared with the lowest was 1.13 (95% confidence interval (CI) 0.73-1.75), the RR for vegetables alone was 1.24 (95% CI 0.79-1.95) and that for fruit alone was 1.45 (95% CI 0.85-2.47). The corresponding multivariate RRs for rectal cancer were 1.12 (95% CI 0.67-1.89), 1.14 (95% CI 0.67-1.93) and 1.41 (95% CI 0.73-2.73). CONCLUSIONS: We found no association between the consumption of fruit and vegetables and the risk of colorectal cancer among the Japanese population.  相似文献   
60.
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