خيارات البحث
النتائج 61 - 70 من 269
Ontogeny, distributions and relative frequencies of the somatostatin-immunoreactive cells in the proventriculus of the chicken embryos with incubation periods
1999
Chang, J.W. | Lee, H.S. (Kyunsan University, Kyungsan (Korea Republic). Department of Biology, Faculty of Natural Science) | Ku, S.K. | Lee, J.H. (Kyungpook National University, Taegu (Korea Republic). Laboratory of Histology, College of Veterinary Medicine)
Ontogeny, distributions and relative frequencies of somatostatin-immunoreactive cells were investigated in the proventriculus of the chicken embryos with incubation periods. Samples were taken from 10 groups(10 days of incubation to hatching) and studied by immunogistochemical methods. The findings were as follows. Somatostatin-immunoreactive cells were observed from 12 days of incubation in the proventricular glands and after that increased with incubation periods. The first observation time of these cells in the epithelium were at 15 days of incubation in the basal portion but in 16 and 17 days of incubation, no immunoreactive cells were observed in the epithelium but after that a few immunoreactive cells were observed in the basal portion and gastric gland regions. The shpaes of these cells were spherical to spindle in the proventricular glands and spherical to round in the epithlium and gastric gland.
اظهر المزيد [+] اقل [-]Studies on the application of bone alkaline phosphatase and percentage of BALP values to total alkaline phosphatase as a marker of bone formation
1999
Kim, N.S. | Choi, I.H. (Chonbuk National University, Chonju (Korea Republic). Department of Veterinary Medicine)
Twenty-one dogs(male 11 heads, female 10 heads) which were about 16 months (16.3+_3.5) old and 10kg(10.1+_2.0) body weight, were allotted randomly into four groups as follows. Group I consisted of five dogs whose muscles were operated for sham muscle injuries. Group II consisted of seven dogs treated for cystic duct obstruction. Group III consisted of five dogs treated for the union fracture model. Group IV consisted of five dogs treated for the nonunion fracture model. Radiographical and histological observations were carried out to determine bone alkaline phosphatase(BALP) and total alkaline phosphatase(TALP) values of each group for 20 weeks after the treatments with the condition of new bone formation. And also the applicability of percentage of BALP values to TALP (B/T) was studied after BALP was compared respectively with TALP. The level of TALP was increased without any relation to bone formation in group II, and all levels of BALP and B/T were increased in group III. The mean of B/T was high in statistical significance, due to varied levels of B/T and BALP. The changes of rates of B/T were significantly increased only in the case of the active new bone formation in group III, union fracture model. It was recognized that the mean values of B/T were statistical significant of the high applicability of the B/T ratio as and index of bone formation.
اظهر المزيد [+] اقل [-]Effects of ischemic preconditioning, K atp channel on the SOD activation and apoptosis in ischemic areperfused skeletal muscle of rat
1999
Ahn, D.C. | Paik, D.J. (Hanyang University, Seoul (Korea Republic). Department of Anatomy, College of Medicine) | Yang, H.H. (Chonbuk National University, Chonju (Korea Republic). Department of Veterinary Anatomy, College of Veterinary Medicine)
Ischemic preconditioning (IPC), i.e., a preliminary brief episode of ischemia and reperfusion, has been shown to reduce the cell damage induced by long ischemia and reperfusion. Superoxide radical which is produced during reperfusion after ischemia was recongnized as a factor of the ischemic injury and it is dismutated into H2O2 and O2 by two types of intracellular superoxide dismutase (SOD), Cu,Zn-SOD in cytoplasm and Mn-SOD in mitochondria. Recently oxygen free radicals are suggested to induce the apoptosis, however mechanism of the reduced apoptosis by ischemic precondition was unknown, while many studies performed in mammalian heart indicated that ATP-sensitive K+(K atp) channel activation related with the protective effects. The aim of present study is toinvestigate 1)whether IP upregulate the Cu,Zn-SOD and Mn-SOD activities, and 2)whether ischemic preconditioning decreases apoptosis via K atp channel activation in timely reperfused skeletal muscle after long ishemia. The experimental animals, Sprague-Dawley rats weighing 250~300g, were divided into 8 group; 1)control group, 2)ischemic preconditioning only groups, 3)pinacidil, a K atp channel opener, treatment only groups, 4)glibenclamide, a K atp channel blocker, treatment only groups, 5)ischemia groups, 6)ischemia after IPC groups, 7)ischemia and pinacidil treatment groups, and 8)IP and ischemia after glibenclamide pretreatment groups. Animals of the control group were administered with the vehicle (DMSO) alone. Pinacidil (1mg/kg) was administred intravenously 5 minutes after initiation of ischemia, and glibenclamide(0.5mg/kg) was injected intravenously 20 minutes before IPC. In rats that were ischemic preconditioned, the left common iliac artery was occluded for 5 minutes followed by 5 minutes of reperfusion by three times usign vascular clamp. Ischemia was done by occlusion of the same artery for 4 hours. The specimens of left rectus femoris muscle were obtained immediately (0 hours), 12 hours, 24 horus after drug administrations, IP or ischemia and reperfusion. The immunoreactivities of SOD and its alterations were observed by use of sheep antihuman Cu,Zn-SOD and Mn-SOD antibodies onthe 10 micro meter cryosections. The incidencies of apoptosis were observed by TUNEL methods with in situ apoptosis detection kit on 6 micro meter paraffine section. The results obtained were as follows: 1. After IPC, immunoreactivities of Cu,Zn-SOD mainly in the small-sized fibers were increased by 24 hours, that of Mn-SOD at 0 hour and 24 hours. 2. No significant changes in immunoreactivities of SDO was observed in the pinacidil and in the glibenclamide treatment only groups, and in the ischemia only groups. 3. The immunoreactivities of the Cu,Zn-SOD were incresed in the ischemia after IPC groups and the ischemia and pinacidil treatment groups. 4. The immunoreactivities of the Cu,Zn-SOD in the IPC and ischemia after glibenclamide pretreantment groups were not increased except for the 12 hours reperfusion group. But, Mn-SOD immunoreactivities were incresed in to 0 hours, 12 hours and 24 hours after reperfusion. 5. In the control group, the IPC only groups, and the pinacidil treatment only groups, negative or trace apoptotic reactions were observed, but the positive apoptotic reaction occured in the glibenclamide treatment groups. 6. Moderate or many number of apoptosis were revealed in the ischemia groups, and also the IPC and ischemia after glibenclamide pretreatment group except for 12 hours and 24 hours after reperfusion. However, the incidence of apoptosis was decreased in the ischemia after IPC groups and in theischemia and pinacidil treatment groups. 7. There is a coincidence between the increase of Cu,Zn-SOD immunoreactivities and the decrease of apoptosis in thepresence of ischemia and reperfusion. These results suggest that the protective effects of ishemic preconditioing may related to the SOD activation, and the ischemic preconditioning decreases the apoptosis partially via K atp channel activation in timely reperfused rat skeletal muscle. It is also suggested that inhibition of apoptosis by IPC may related with the SOD activation.
اظهر المزيد [+] اقل [-]Distribution and characteristics of Staphylococcus aureus subtypes isolated from dairy herds
1999
Yoo, J.H. | Park, H.M. | Oh, T.H. | Sohn, D.H. | Han, H.R. (Seoul National University, Suwon (Korea Republic). Department of Veterinary Internal Medicine, College of Veterinary Medicine)
Staphylococcus aureus is one of most prevalent intramammary pathogens and have characteristics which are not easily eradicated. Recently, to understand the sources and transmission of S aureus, many studies have focused on the subtyping of field isolate. This study was preformed to investigate the distribution pattern and characteristics of the isolates using phenotyping and genotyping. Samples were collected from milk of each udder, cow bodies (perianal region, vagina, tail, udder skin, sole) and environment (floor, liner, milker's hand, water, towel, insect) from 6 herds located in Kyung-gi province. Forty five strains of S aureus were isolated from 3 dairy herds (A, B, C) and were typed by hemolytic pattern, antibiotic resistant pattern, enterotoxin typing and PCR-based DNA fingerprinting. Slime productivity was also compared by each subtype to examine potential infectiousness. Of 45 strains, 41 were isolated from milk samples and 4 were isolated from liners. No strains isolated in the bodies and environment. Forty five strains isolated were classified as 18 subtypes by phenotyping and genotyping. There was common subtype between A and B herd, but the subtype of C herd showed different pattern. Among predominant subtypes, 60% of S aureus strain isolated from A and B herd showed subtype I and 50% of S aureus strain isolated from C herd belong to subtype VI and XII. Neither somatic cell count (SCC) nor slime production was significantly different between predominant and minor subtypes. In summary, the study revealed that liners play more important roles in the mode of transmission than enmironmental sources. Several subtypes can be found in a herd, only a few subtype, however, was largely associated with the majority of infection.
اظهر المزيد [+] اقل [-]The karyotype of Korean native goat (Capra hircus)
1999
Oh, S.H. | Yun, Y.M. | Seong, J.K. (Yonsei University, Seoul (Korea Republic). Department of Laboratory Animal Medicine, Medical Research Center, College of Medicine) | Yoon, Y.S. | Lee, J.S. (Seoul National University, Suwon (Korea Republic). Department of Veterinary Histology and Embryology, College of Veterinary Medicine) | Lee, H.S. (Seoul National University, Suwon (Korea Republic). Department of Veterinary Anatomy, College of Veterinary Medicine)
We investigated the cytogenetic characteristics of Korean native goat(Capra hircus). Chromosome slides were prepared from peripheral blood cell cultures. GTG, GBG, RBG and CBG-banding techniques were employed on those slides. The high resolution karyotype of Korean native goat could be made with the incorporation of BrdU. Korean native goat has 60 chromosomes composed of 58 autosomes and XY or XX sex chromosomes. All of autosomes of Korean native goat were acrocentric chromosomes. X chromosome was submetacentric and Y chromosome was metacentric. The GTG, GBG and RBG-band patterns of Korean native goat were similar to those of other goats. CBG-band regions were distince at the proximal portion of the long arms of all autosomes in Korean native goats. According to our investigation, there was no significant difference in chromosomal band patterns between Korean native goat and other goats. It might be necessary ot use molecular genetic markers for clarifying the genetical characteristics of Korean native goat whose biological characteristics are not clearly defined.
اظهر المزيد [+] اقل [-]The reasons of drug residues in bulk milk
1999
Kang, J.H. | Kim, J.S. | Lee, W.C. (Konkuk University, Seoul (Korea Republic). School of Veterinary Medicine) | Choi, P.S. (Konkuk Dairy, Seoul (Korea Republic). Department of Dairy Control)
The 102 farms received a positive result of the milk drug residue test were selected to investigate the reasons of drug residues in bulk milk. The most frequent causes of drug residues were milker or producer mistakes (28.4%), failure to observe withdrawal time (21.5%), and withholding milk from treated quarters only (19.6%). Milker or producer mistakes occurred high at the farms having a parlor system (4 cases out of 11 farms), and related to the inadequate records and marking of treated cows. The lack of knowledge on the absorption of antibiotic from treated quarters and its excretion from untreated quarters caused mainly withholding milk from treated quarters only. Among the 91 farms identified the cause of drug residues, most of the route of drug administration was intramammary infusion (81.3%), and mostly drug used for the treatment of cows was beta-lactam antibiotics (57.1%).
اظهر المزيد [+] اقل [-]An immunohistochemical study on the endocrine pancreas of the bean goose, Anser fabalis, Latham
1999
Lee, J.H. | Ku, S.K. (Kyungpook National University, Taegu (Korea Republic). Department of Histology, College of Veterinary Medicine) | Lee, H.S. (Kyungsan University, Kyungsan (Korea Republic). Faculty of Basic Science, College of Natural Science)
The regional distribution and relative frequency of the endocrine cells in the pancreas of the bean goose were investigated by immunohistochemical methods using 6 types of the specific antisera. Spindle shpaed serotonin-immunoreactive cells were detected in the exocrine portions. Spherical or spindle shpaed glucagon-immunoreactive cells were observed in the exocrine and dark and mammalian type islets. In the dark type islets, numerous cells were dispersed throughout whole islets but they were located in the peripheral regions of the mammalian type islets. No glucagon-immunoreactive cells were detected in light type islets. Round or spherical shpaed insulin-immunoreactive cells were observed in the exocrine and dark, light and mammalian type islets. They were observed in the exocrine regions with a few numbers. Extremely rare cells were detected in central portion of the dark type islets but moderate to numerous cells were found in the central regions of the mammalian and light type islets, respectively. Spherical or spindle shaped somatostatin-immunoreactive cells were observed in the exocrine and dark, light and mammalian type islets. A few single cells were detected in the exocrine portions. In the dark type islets, numerous cells were dispersed throughout whole islets but a few to moderate numbers of cells were located in the peripheral regions of the light and mammalian type islet. Moderate numbers of the bovine pancreatic polypeptide-immunoreactiv ecells were found in the exocrime portions with round, spherical or spindle shape. But no bovine Sp-1/chromogranin-immunoreactive cells were observed in this study.
اظهر المزيد [+] اقل [-]Pathological evaluation of renal changes induced by myltiple nephropathogenic factors in SPF chickens
1999
Kang, K.I. | Hahn, T.W. | Han, J.H. (Kangwon National University, Chuncheon (Korea Republic). Department of Veterinary Medicine) | Mo, I.P. | Kwon, Y.K. | Kang, M.S. (National Veterinary Research and Quarantine, Anyang (Korea Republic).)
Renal failure is one of the main causes of economic impacts in the poultry industry and complex syndrome with different severity of clinical signs caused by multiple nephropathogenic factors such as infectious bronchitis viral infection and excess salt and calcium in diet. To evaluate the correlation between severity of renal failure and the causative nephropathogenic factors, one-day-old specific pathogen free chickens were treated with either single causative factor or multiple causative factors described as above. Each group was designed as control for non-treated control, IB for infectious bronchitis virus (IB virus) infection, IBHNa for IB virus infection with high diet salt, IBHCa for IB virus infection with high diet calcium, IBHNC for IB virus infection with high diet salt and calcium, HNa for high diet salt, HCa for high diet calcium and HNC for high diet salt and calcium. Chickens were inoculated with IB virus at 1-day-old and remained on their respective diets until 21 day of age. Plasma Na+, Cl-, BUN, creatinine, calcium and uric acid values were examined. The results obtained were as follows; IB virus and high dietary calcium combined treatment showed elevated plasma uric acid. BUN and creatinine values were not characteristic on chicken renal failure. But plasma uric acid values were increased according to renal lesion. Hypercalcemia and hyperuicemia did not induce urate deposition and mineralization in the kidney.
اظهر المزيد [+] اقل [-]Pathological evaluation of renal changes induced by multiple nephropathogenic facotrs in SPF chickens
1999
Kang, K.I. | Hahn, T.W. | Han, J.H. (Kangwon National University, Chuncheon (Korea Republic). Department of Veterinary Medicine) | Mo, I.P. | Kwon, Y.K. | Kang, M.S. (National Veterinary Research and Quarantine, Anyang (Korea Republic).)
Renal failure is one of the main causes of economic impacts in the poultry industry and complex syndrome with different severity of clinical signs caused by multiple nephropathogenic factors such as infectious bronchitis viral infection and excess salt and calcium in diet. To evaluate the correlation between severity of renal failure and the causative nephropathogenic factors, one-day-old specific patogen free chicks were treated with either single causative factor or multiple causative factors described as above. Each group was designed as control for non-treated control, IB for infectious bronchitis virus (IB virus) infectio, IBHNa for IB virus infection with high diet salt, IBHCa for IB virus infectio with high diet calcium, IBHNC for IB virus infection with high diet salt and calcium, HNa for high diet salt, HCa for high diet calcium and HNC for high diet salt and calcium. Chickens were inoculated with IB virus at 1-day-old and remained on their respective diets until 21 day of age. The high dietary salt feeding groups such as IBHNa, IBHNC, HNa, HNC increased water intake, watery diarrhea, general subcutaneous edema and the high dietary calcium feeding groups such as IBHCa and IBHNC showed severe visceral gout. Two more than treated groups caused high mortality in comparison with the single treated groups. In virus exposure significantly increased urate deposition and lymphocytic interstitial nephritis. Espcecially urate deposition dramatically increased when excess diet calcium was combined together. In excess diet salt treated groups enlarged edematous kidneys were observed and hypertrophy of glomeruli were showed. These results suggest that IB virus enhanced the incidence and severity on chicken renal failure clearly related to the quantity of salt and calcium.
اظهر المزيد [+] اقل [-]An assessment of statistical errors in articles in the Korean journal of veterinary research
1999
Park, S.I. (Seoul National University, Seoul (Korea Republic). Department of Internal Medicine, College of Veterinary Medicine)
The purpose of this study is to assess the suitability of the statistical techniques employed in papers published in the Korean Journal of Veterinary Research from March 1997 to March 1999 and it is hoped that the critical assessment may be of help to other researchers preparing their works for publication. Of the 246 original papers 94 were inclluded in the analysis. of 62 papers with the measure of central location and dispersion of data 34(54.8%) used them correctly:9 (39.1%) of 23 for t-test; 1 (33.3%) of 3 for correlation analysis; 7 (43.8%) of 16 for analysis of variance (ANOVA); 5 (62.5%) of 8 for chi-square test; 44 (71%) of 62 for description of p-value. A number of papers employed ANOVA did not perform subsequent analysis of multiple comparison. Compared to the results of others, relatively higher proportion of papers in the present study was evaluated as appropriate analysis. The reason is that papers described insufficiently on the study design were not included, and evaluation items were restricted to the cases violated seriously ingerent assumptions for each statistical technique. Statistical misuse or abuse appeared in the study is due to lack of knowledge on statistics and short of its importance for improvement the quality of paper. Because an inappropriate analysis can lead the readers to misunderatand on findings, observed statistical analyses must be valid,and correctly undertaken. It is suggested that more intensive statistical refereeing are needed,and the communication should be allowed for the controversial points.
اظهر المزيد [+] اقل [-]