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991.
Myelolipomas of the liver in a domestic cat 总被引:1,自引:0,他引:1
I M Gourley J A Popp R D Park 《Journal of the American Veterinary Medical Association》1971,158(12):2053-2057
992.
Park JH Kang KS Lee YS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(7):767-771
Four doses (equivalent to 4, 2, 1, and 0.5 liter water) of organic extracts from raw, treated and drinking waters sampled from seven different treatment plants in five cities in Korea were challenged to the Ames test using S. typhimurium strains TA98 and TA100 in the presence/absence of S9 mix. The mutagenicity was usually observed from chlorine-treated (28.6%) and drinking (42.9%) waters rather than raw (3.4%) waters. The strain TA98 (33.3%) was more sensitive to detect the mutagenicity of water samples than the strain TA100 (16.7%). However, the absence of S9 mix showed higher mutagenic activity of waters compared to the presence of S9 mix, corresponding to the detection of 42.9% and 7.1%, respectively. These results indicate that the bacterial mutagenicity of treated and drinking waters may be derived from chlorination in water treatment plants but that the mutagenicity in humans may be limited due to enzymatic metabolism. 相似文献
993.
994.
cDNA microarray gene expression analysis and toxicological phenotype for anticancer drug 总被引:1,自引:0,他引:1
Lee GJ Lee WS Jeon KS Um CH Kim YS Kim SJ Lee CH Yoon HK Hwang SY Park JS Hwang JW Kang KS Lee YS Kim MS Chon KJ Yeo CD Kang JS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1339-1345
Toxicogenomics, the subdiscipline that merges genomics with toxicology, hold the promise to contributing toward the goal of elucidating mechanism by studying genomic profiling related with various drugs. The application of gene expression profiling technology to examine multiple genes and signaling pathways promises a significant advance in understanding the toxic mechanisms of various drugs and prediction of new drug candidate. Toxicogenomics is emerging field combining genomics and bioinformatics to identify and characterize mechanisms of toxicity of drug and various compounds. The principal hypothesis underlying on this field is that chemical-specific pattern of altered gene expression is related with each chemicals properties, especially toxicological property, and it will be revealed using high-density microarray analysis of sample from exposed organisms. So, in this study we compare the gene expression pattern of two anticancer drugs paclitaxel and orally absorbable paclitaxel, using the cDNA microarray. And from the result of this study, it is possible to provide the new possibility for genome-wide insight into mechanism of their anticancer activity and toxicological phenotype. 相似文献
995.
ABSTRACT The infection of Japanese pear by Venturia nashicola, the cause of scab on Asian pears (Japanese pear, Pyrus pylifolia var. culta; Chinese pear, P. ussuriensis), was examined using light and electron microscopy to determine the mechanism of resistance in pears. Early stages of infection were similar on the susceptible cv. Kosui, the resistant cv. Kinchaku, and the nonhost European pear (P. communis) cv. Flemish Beauty. V. nashicola penetrated only the cuticle layer on pear leaves and formed subcuticular hyphae on all three cultivars. Hyphae were localized in the pectin layer of pear leaves and never penetrated into the cytoplasm of epidermal cells. This restriction of fungal growth suggested that pectinases released by infection hyphae or subcuticular hyphae may be important in infection. Subcuticular hyphae were modified ultrastructurally in the pectin layer of resistant pear cultivars accompanied by fungal cell death. In contrast, fungal cells appeared intact in susceptible pear cultivars, suggesting the existence of resistance mechanisms. 相似文献
996.
Park JH Lee BJ Lee YS Park JH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(7):725-729
Tightly spiral bacteria were observed only in the pyloric mucosa of 4 (8.0%) of 50 swine stomachs, mainly in the surface of epithelia, the gastric pits and the lumen of gastric glands. The presence of the spiral bacteria was significantly associated with chronic pyloric gastritis (p<0.05). Mean gastritis score of the bacteria-positive pyloric mucosa was 3.25 +/- 0.25, whereas that of the bacteria-negative pyloric mucosa was 2.37 +/- 0.12. Parakeratosis and hyperkeratosis were spontaneously seen in the mucosa layer of pars oesophagea, regardless of the bacterial infection. Marked infiltration of mononuclear cells and granulocytes were seen in the cardiac mucosa, regardless of the bacterial infection. Mean gastritis score of the bacteria-positive cardiac mucosa was 3.27 +/- 0.32, whereas that of the bacteria-negative cardiac mucosa was 2.84 +/- 0.13. There was no significant difference between the bacteria-positive and negative cardiac mucosa (p>0.05). Inflammatory response in the fundic mucosa was rare (gastritis score=0.75 +/- 0.08). The tightly spiraled bactera were not cultured with various culture media. These results suggest that the presence of tightly spiraled bacteria is associated with only the pyloric gastritis in pigs. 相似文献
997.
Kap Seung Yang Young Ok Choi Yong Min Kim Sang Hee Park Cheol Min Yang Yong Joong Kim Soon Young Soh 《Fibers and Polymers》2000,1(2):97-102
Pitch precursors were synthesized from coal tar(CT) and pyrolysis fuel oil(PFO, petroleum residue oil) at relatively low temperature
of 250°C, in the presence of borontrifluoride/diethyletherate complex(BFDE) as a catalyst and nitrobenzene(NB) as a co-catalyst.
The softening point, nitrogen content and carbon yield increased with an increase of concentration of NB. The pitch precursors
with good spinnability were prepared by removing the volatile components through N2 blowing. The precursor pitches were spun through a circular nozzle, stabilized at 310°C and finally carbonized at 1000°C.
The optically anisotropic structure formed at the absence of NB was changed into isotropic structure, showing a decrease in
size of the flow domain. The hollow carbon fiber could be prepared in the process of stabilization. The results proposed that
the morphology of carbon materials could be controlled by changing the concentration of catalyst and/or co-catalyst and/or
stabilization condition that affect on the mobility of molecules during carbonization. 相似文献
998.
999.
Lucinda van Stee Sarah Boston Ameet Singh Fiona Park Danielle Richardson Anthony Abrams-Ogg Andrew Vince 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(9):849-856
We describe 3 cases of cats that were presented with a sudden onset of monoparesis as a result of arterial thromboembolism without evidence of cardiovascular disease that were subsequently diagnosed with a primary pulmonary carcinoma. Arterial tumor thromboemboli due to pulmonary carcinoma should be considered as a differential diagnosis in cases of lameness or paresis in older cats. We theorize that large tumor emboli may obstruct peripheral arteries leading to acute monoparesis. 相似文献
1000.
The assembly properties of two- and three-component rod-like building blocks consisting of gold and polymer block domains have been investigated. These structures behave like mesoscopic amphiphiles and form a series of single-layer superstructures consisting of bundles, tubes, and sheets depending upon the compositional periodicity. Unlike molecular systems, the template used to initially synthesize them plays a critical role in the assembly process by prealigning them in a manner that facilitates their assembly by optimizing the correct collisional orientation upon dissolution of the template. Tubular structures with tailorable diameters can be assembled in a predictable manner on the basis of an estimate of the hybrid rod packing parameters. 相似文献