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111.
112.
随着各种生物全基因组测序工作的不断深入,越来越多的核酸序列清晰的呈现在世人面前。与此同时,我们明确知道空间结构的蛋白质数目却增长缓慢,而且两者之间增长速度的差异正在进一步扩大。因为蛋白质的生物学功能在很大程度上取决于其空间结构,所以弄清楚蛋白质的结构进而理解其结构与功能的关系具有重要意义。但通过实验方法获得蛋白质结构不仅成本高而且速度慢, 相似文献
113.
Kawano K Mori S Hirashima T Man ZW Natori T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(11):1219-1228
We conducted protein loading to examine the progression and pathogenesis of diabetic nephropathy. For this experiment, male OLETF, LETO, F344 and BN rats were used. This experiment was performed on rats between 5 and 30 weeks of age. Examination parameters included body weight, food intake, oral glucose tolerance test (OGTT), urinary protein level (UP), urinary albumin level (UA), glomerular filtration rate (GFR), kidney weights, light microscopy (LM) and electron microscopy (EM). In the protein-loaded OLETF group, the UP level was markedly increased 20 weeks or more after birth. In OLETF control group, GFR were higher than those in other strains. Glomerular hypertrophy and kidney weights were markedly increased in protein-loaded groups in OLETF rats. Thirty weeks after birth, EM showed that the number of polyethyleneimine (PEI) of the glomerular basement membrane (GBM) in protein-loaded OLETF group was significantly decreased compared to that in control group. These changes in OLETF rats were more marked in the protein-loaded group than those in the control group. LM showed that the number of exudative lesions with fibrin-cap in the protein-loaded OLETF group was significantly increased than those in control group. In OLETF rats, protein loading caused deterioration of nephropathy at 30 weeks of age. Therefore, it was demonstrated that not only blood sugar control but also protein intake factors play important roles in the deterioration of nephropathy in OLETF rats. 相似文献
114.
Flow cytometric assessment of ethylene glycol monoethyl ether on spermatogenesis in rats 总被引:1,自引:0,他引:1
Yoon CY Hong CM Cho YY Chung YH Min HK Yun YW Lee BJ Yang KH Lee YS Kim CK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(2):207-212
The effects of ethylene glycol monoethyl ether (EGEE) on testicular cell populations in rats were investigated by a flow cytometric method. Rats were administered by gavage with EGEE at the various doses of 0 (saline alone), 100, 200, 400, and 800 mg/kg body weight/day for 4 weeks. The treatment of EGEE caused decreases in the weight of testis and epididymis and in the number of testicular cells. Histopathologically, exfoliation of germ cells into the tubular lumen was observed at the doses of above 200 mg/kg. The treatment of EGEE at the dose of 400 mg/kg caused moderate testicular degeneration. A significant depletion of haploid cells and a disproportionate ratio of diploid and tetraploid cells were observed as determined by flow cytometric analysis. These results indicate that the toxic effect of EGEE on the male reproductive system may be strongly associated with the disproportion of testicular germ cells. 相似文献
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ABSTRACT Hybrid isolates of Phytophthora nicotianae x P. cactorum from five different hosts (Cyclamen, Lavandula, Lewisia, Primula, and Spathiphyllum spp.) were identified by their atypical morphology and their well-defined heterozygous isozyme patterns. The hybrid nature of these isolates was tested by restriction fragment length polymorphism analysis of the internal transcribed spacer (ITS) region of rDNA, generating fragments typical for both P. nicotianae and P. cactorum. In hybrid isolates, polymerase chain reactions (PCR) with primers derived from unique parts of the ITS region (ITS-PCR) of both species yielded a combination of unique amplicons typical of both parental species. Eleven hybrid isolates, three isolates of each parental species and two atypical isolates from Rhododendron and Idesia spp. close to P. cactorum, were analyzed for amplified fragment length polymorphisms (AFLP). Consistent differences in AFLP patterns existed among the hybrid isolates, strongly indicating that these hybrids have arisen from independent hybridization events between P. nicotianae and P. cactorum. The two atypical isolates morphologically resembling P. cactorum were identical to the latter species in ITS-restriction fragment length polymorphism and response to the specific PCR primers but were intermediate between P. nicotianae x P. cactorum and P. cactorum in isozyme profiles and AFLP patterns. Since the introduction of hydroponic systems in greenhouses in the Netherlands, outbreaks of Phytophthora diseases are occurring in previously unaffected host species. This may be due to interspecific hybridization events resulting in novel pathogenic behavior. 相似文献
117.
Taehoon Oh Md. Mizanur Rahman Ji-Hey Lim Mi-Sun Park Dae-Yong Kim Jung-hee Yoon Wan Hee Kim Masanori Kikuchi Junzo Tanaka Yoshihisa Koyama Oh-Kyeong Kweon 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(1):73-77
This study was performed to evaluate the effect of beta-tricalcium phosphate and poly L-lactide-co-glycolide-co-epsilon-caprolactone (TCP/PLGC) membrane in the repair of partial bone defects in canine proximal humerus. Three adult mixed-breed dogs were used during the experimental period. The length of the defect was quarter of the full length of humerus, and width of the defect was quarter of middle diameter of the lateral aspect of humerus. The humeri of each dog were divided into treatment (TCP/PLGC) and control groups. The defect was covered with TCP/PLGC membrane in treatment group. To evaluate regeneration of the bone, computerized tomography (CT) and histopathologic examination were performed. The radiopaque lines were appeared at the original defect sites in TCP/PLGC group but below the original site in control at 4th week. Radiopacity and thickness of the defect sites, and radiopaque lines were more increased at 8th week than those of 4th week. Histopathologic findings revealed fibrous connective tissue migration into the defect and the migration inhibited the structure of new cortex to be placed in the original level in control whereas new cortex growth was found in the level of original line in TCP/PLGC group. However, the new cortical bone in the TCP/PLGC group was thinner and less organized than the adjacent intact cortex, and the amount of new cancellous bones were also scanty. The result suggested that TCP/PLGC membrane is a good guided bone regeneration material to restore the original morphology of humerus in partial defect. 相似文献
118.
Won-Il Jeong Sun Hee Do Da-Hee Jeong Jae-Yong Chung Hai-Jie Yang Dong-Wei Yuan Il-Hwa Hong Jin-Kyu Park Moon-Jung Goo Kyu-Shik Jeong 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(3):299-301
Three dead dogs were brought to the College of Veterinary Medicine, Kyungpook National University for study. Clinically, all the dogs showed emaciation, anorexia, depression, hemorrhagic vomiting and diarrhea for 7~10 days before death. All the clinical signs were first noted for about one month after feeding the dogs with commercial diets. At necropsy, all 3 dogs had severe renal damage with the same green-yellowish colored nephroliths in the renal pelvis. They also showed systemic hemorrhage and calcification of several organs, which might have been induced by uremia. Microscopically, necrosis, calcification and calculi were detected in the renal tubules, and especially in the proximal convoluted tubules and collecting ducts of the kidney. These findings were supportive of a mycotoxic effect, and especially on their kidneys. However, the precise cause of the toxic effect in these cases of canine renal failure could not be determined. 相似文献
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120.
Water shortage has become a major agricultural concern, and “The Sustainable Water Resources Research Program” in Korea is currently addressing this problem through the development of treatment systems for reclaiming wastewater and the assessment of human health risks associated with its reuse. Through this program, started in 2001, many studies have examined various water resources. Reclaiming wastewater is one way to alleviate water-shortage pressures, and one of the major potential uses of reclaimed water is irrigation. However, the main concern with reusing reclaimed wastewater is the increased likelihood of human contact that might result in exposure to pathogens and increased health risks. Relatively few studies have examined the toxic risks using reclaimed wastewater for irrigation in rice paddy fields. This study provides an overview of methods for quantitative microbial risk assessment and toxic risk assessment of heavy metal concentrations developed in the previous studies that can be applied to the evaluation of rice paddy fields irrigated with reclaimed wastewater in South Korea. 相似文献