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561.
FT-Ir and ESR were used for on the investigation of the CCl4-induced peroxidation of rat liver microsomes in combination with biochemical methods. Lipid peroxidation was assayed by TBA reagent in the presence of CCl4 and NADPH. The CCl3. radical was detected by ESR spectroscopy with a spin trapping reagent of PBN. The FT-IR spectroscopy revealed that absorption band of -C-H in -C=C-H decreased in intensity at 3012 cm-1, but the absorption bands of the phosphate head and choline in the phospholipids did not significantly change between 1300 and 900 cm-1. These findings were interpreted to be due to the removal of H. from -C=C-H by radicals as the first step of lipid peroxidation, and to the absence of dephosphorylation of phospholipids in the microsomal membrane. This is the first IR spectroscopic evidence indicating the nature of damage to a microsomal membrane caused by CCl4 treatment. The spectroscopies used here demonstrated that they are useful tools to observe the damage to microsomal membranes.  相似文献   
562.
In 1983, 1197 human cases (3.04/10 000 population) of epidemic encephalitis were reported, but practically no further cases of this condition have been reported since 1984. Human cases of encephalitis occurred primarily among those younger than 19 years in rice-field regions in the autumn. The mean number of patients registered annually with hemorrhagic fever from 1979 to 1988 was 46.5 (0.19/10 000 population), being highest in 1979 (73 cases, 0.19/10 000) and lowest in 1982 (32 cases, 0.08/10 000). Hemorrhagic fever occurred among adults mainly in autumn in mountain regions. Two cases of rabies in human and dog were reported in 1984.  相似文献   
563.
Salmonella enterica serovar Typhimurium (S. Typhimurium) isolated and identified from swine were subjected for the analysis of antibiotic resistance pattern and clinically important class 1 and 2 integrons. In addition, S. Typhimurium isolates exhibiting ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline and florfenicol (ACSSuTF) resistance pattern as described in most Salmonella enterica serotype Typhimurium definitive type 104 (DT104) were characterized by polymerase chain reaction. All the isolates were resistant to more than four antibiotics and showed the highest resistance to streptomycin (94.1%), followed by tetracycline (90.1%), ampicillin (64.7%), chloramphenicol (56.8%) and gentamicin (54.9%). MIC value for the ten isolates ranged between 0.125-2 mug/ml for ciprofloxacin. Among the beta-lactams used, only one of the isolate exhibited resistance to ceftiofur (MIC 8 microg/ml). Sixty eight percent of these multi drug resistance (MDR) S. Typhimurium isolates carried clinically important class 1 integron with 1kb (aadA) and/or 2kb (dhfrXII-orfF-aadA2) resistance gene cassettes. This study reports the increasing trend of multi drug resistance (MDR) S. Typhimurium with clinically important class 1 integron in pigs. In addition, emergence of the ACSSuTF-type resistance in S. Typhimurium PT other than DT104 may limit the use of resistance gene markers in its detection methods by PCR.  相似文献   
564.
We report the first case of a primary subcutaneous leiomyosarcoma that originated in the hind leg of a hamster and metastasized to the bone marrow, lung and diaphragm. A 10-month-old female Syrian golden hamster was presented with a large, firm, white subcutaneous mass in the right hind leg. The tumor invaded into the bone marrow and small nodules were also present in the lung and diaphragm; however, no tumor masses were found in the visceral organs. Histologically, the tumors were spindle cell sarcomas, composed of densely packed pleomorphic spindle cells with oval to elongate nuclei and moderate amounts of eosinophilic cytoplasm. Immunohistochemically, the neoplastic cells were positive for vimentin, desmin, and smooth muscle actin, but negative for alpha-sarcomeric actin and S-100. Thus, the diagnosis was primary leiomyosarcoma of the hind leg with metastasis to the bone marrow, lung and diaphragm. To the best of our knowledge, this is the first report of spontaneous primary subcutaneous leiomyosarcoma of the hind leg with distant metastasis in laboratory animals.  相似文献   
565.
We examined the age-related changes of calbindin D-28k (CB)-immunoreactive neurons and overall populations of neurons in the myenteric plexus of gerbil duodenum using whole mount preparations and immunohistochemistry. The circumference of duodenum increased age-dependently. CB-immunoreactive neurons were observed in all groups, and most of them had the Dogiel type II morphology. The fully developed cobweb-like structures were observed in the myenteric plexus of duodenum at postnatal month (PM) 3 to 24. Although the highest numbers of CB-immunoreactive neurons and overall population were observed in PM 1.5, it is related with significant increase of the size of circumference between PM 1.5 to PM 3. CB-immunoreactive neurons were slightly decreased with age between PM 3 to PM 24. We have also found that whole numbers of myenteric neurons were also significantly decreased in PM 24 group. These results suggest that loss of overall numbers of myenteric neurons and CB-immunoreactive neurons may be related with age-related neurodegeneration and functional loss of duodenum in the gerbil.  相似文献   
566.
A total of 280 weaned pigs (Landrace x Yorkshire x Duroc) were used in a 28-d growth study to investigate the effect of feeding different levels of potato proteins on growth performance, nutrient digestibility, immune response, small intestinal morphology, and bacterial populations in feces and large intestine. Pigs (initially 6.42 +/- 0.74 kg of BW and 23 +/- 3 d of age) were randomly allotted to 5 treatments on the basis of BW, each treatment composed of 4 pens, each pen having 14 pigs. Dietary treatments included positive control (PC; basal diet + 150 mg/kg apramycin and 10 mg/ kg colistin sulfate); and potato protein (PP), consisting of the basal diet with 0, 0.25, 0.50, or 0.75% of potato protein. Diets were fed in 2 phases: phase I (d 0 to 14 postweaning) and phase 2 (d 14 to 28 postweaning). Potato protein was extracted from a value-added type of the new potato variety, Solanum tuberosum L. cv. Gogu valley, and was shown to have a minimum inhibitory concentration of 300 to 500 mug/mL. Performance of PC was compared with 0.25 to 0.75% PP, whereas linear and quadratic trends of increasing PP (0 to 0.75% PP) were tested. Over the 28-d trial, pigs fed the PC diets showed improved overall ADG (P < 0.05) and G:F (P = 0.090) compared with pigs fed PP, whereas increasing levels of PP linearly improved ADG (P < 0.05), ADFI (P = 0.052), and G:F (P = 0.098). The digestibility of DM and CP in both the phases was greater in PC than PP, and feeding of PP linearly improved the DM digestibility (P < 0.05) in phase II. The bacterial populations in the feces of pigs fed PC and PP were comparable, except for total bacteria and coliform bacteria in the feces at d 14 and 28, which were decreased in PC; and feeding of PP was effective in linearly reducing the populations of microbes in feces and contents of cecum, colon, and rectum. There was linear increase (P < 0.10) in skin-fold thickness in response to phytohemagglutinin with an increase in PP levels. Haemagglutinin titers on d 21 were greater (P = 0.054) in PC, and at d 28 the haemagglutinin titers were quadratically affected in pigs fed PP (P = 0.070). There was a trend toward a decrease in crypt depth (P = 0.068) and a greater villus height:crypt depth ratio (P = 0.082) of ileum in PC compared with PP. These results suggest that PP may be an alternative to medicated feed with antibiotics because it showed antimicrobial activity by effectively reducing the population of coliform bacteria and also improved the performance of weanling pigs.  相似文献   
567.
568.
An DJ  Yoon SH  Park JY  No IS  Park BK 《Veterinary microbiology》2008,132(3-4):389-395
We sequenced the hemagglutinin (H) genes from four canine distemper virus (CDV) isolates obtained from three dogs and a marten in Korea. These sequences were included in subsequent H gene-focused phylogenetic tree analysis of 89 CDV strains. This analysis revealed eight clades designated as EU1, EU2, EU3, NA1, NA2, Asia 1, Asia 2 and Vaccine. Three of the Korean isolates (97Jindo, 98Marten and 07D111) occurred in the Asia 2 group that also contains many Japanese CDV strains isolated in 1998. The remaining Korean strain (07Q72) fell into the Asia 1 group. The 21 H protein sequences of 25 Asia 1 strains are generally predicted to bear nine potential N-linked glycosylation sites. In contrast, the 9 H protein sequences of 12 Asia 2 strains had eight potential N-linked glycosylation sites. The remaining strains had six (98Marten and 07D111) and seven (97Jindo) potential N-linked glycosylation sites.  相似文献   
569.
The successful eradication of pseudorabies in U.S. domestic swine was accomplished through the use of glycoprotein E (gE) deleted modified live virus vaccines and an accompanying gE differential enzyme-linked immunosorbent assay (ELISA). Yet, pseudorabies virus (PRV) was established in feral swine in the United States, becoming a potential reservoir of PRV for infection of domestic swine and other native wildlife. A critical need for the current PRV surveillance program in the United States is the rapid detection of PRV infection. For this reason, a set of 2 real-time polymerase chain reaction (PCR) assays by using TaqMan chemistry was developed and evaluated for their capability in the detection and differentiation of field and vaccine strains of PRV. PCR primers and probes were designed for gB and gE genes of PRV, respectively. The newly developed PRV-specific real-time PCR assays could detect all wild-type PRV isolates from diagnostic submissions and differentiate them from vaccine strains. The analytical sensitivity of the assays was approximately 0.1 plaque-forming units per reaction. The assays were highly specific for PRV, because no positive results were obtained from testing other common swine viral pathogens and other animal herpesviruses. The results of testing samples from domestic and feral swine and from bovine showed that the real-time PCR assays are more sensitive than gel-based PCR. These results demonstrated the potential application of the developed real-time PCR assays as a differential test for rapid and specific detection of PRV in domestic and feral swine, as well as nonporcine species that can be infected with PRV and serve as carriers.  相似文献   
570.
Handling practices of specimens may affect the sensitivity or specificity of diagnostic tests. In this study, as part of the Voluntary Iowa Bovine Viral Diarrhea Virus Screening Project held in 2006, 2 sample-handling practices were evaluated to determine how they affect the sensitivity and specificity of the antigen-capture enzyme-linked immunosorbent assay (ACE) for bovine viral diarrhea virus (BVDV). The null hypotheses investigated were 1) that maintenance of samples at room temperature would not be associated with decreased sensitivity, and 2) that continued use of a single pair of ear notchers would not be associated with cross-contamination of virus from 1 notch to another and reduce specificity. These hypotheses were tested in 2 studies by collecting known positive and negative samples and giving groups of samples different treatments. The first study used ACE on 4 groups of skin samples, all from a known-positive animal. Each group was subjected to different lengths of time at room temperature, from 24 to 96 hours at 24-hour intervals. No difference in test results was found between specimens subjected to different lengths of time at room temperature. The second study tested the effects of giving 3 different treatments to an ear notcher in between sample collecting (water rinse, Nolvasan solution rinse, or no treatment) on ACE results. No effect on sensitivity or specificity of ACE was observed. No difference in test results was found between the 3 ear-notcher treatment groups. The sample handling practices evaluated appeared to have little impact on test sensitivity or specificity of ACE for BVDV.  相似文献   
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