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1.
Oxidative damage to the membrane in canine erythrocytes with inherited high Na, K-ATPase activity (HK cells) was compared with that in normal canine cells (LK cells). When 30 mM beta-acetylphenylhydrazine (APH) was applied to HK and LK cells, lipid peroxidation and hemoglobin denaturation occurred. Lipid peroxidation determined from malondialdehyde (MDA) formation was significantly lower in HK than in LK cells so far as endogenous glutathione (GSH) concentration was maintained at appropriate levels. With the depletion of GSH, MDA formation was accelerated and difference between HK and LK cells was not significant. Denatured hemoglobin bound to the membrane protein was less in HK than in LK cells. During incubation with APH, osmotic fragility increased markedly in LK cells, while HK cells showed very little change. The amounts of total lipid, total and free cholesterol, glycolipid, phospholipid and fatty acids were essentially the same in both cell types. Fatty acid compositions showed very small differences. The membrane of HK cells thus appear to have greater protection against oxidative damage induced by APH, owing to the presence of excess GSH in HK cells. The capability of HK cells to withstand oxidative damage would not be due to differences in membrane lipid compositions.  相似文献   
2.
Based on the Chiang's method, the life table for cats was constructed from the death data of 3936 cats. They died in the Kanto area and were buried in an animal cemetery in Tokyo from June 1981 through May 1982. This life table seems to be the first one for domestic pet cats. The expectation of life for cats was 4.2 years at age 0, 5.0 years at age 1, 5.4 years at age 4, 5.3 years at age 5, 3.5 years at age 10, and 2.2 years at age 15. The maximum age at death was 22 years. From age 0 to age 5, the probability of dying for cats was higher than that for dogs, but over 6 years of age it seemed that Gompertz's equation was applicable to this life table for cats. From these results, if the probability of dying for cats at early ages decreases, the fundamental pattern of dying curve for cats seems to be a similar figure of dogs. The life table was constructed for different breeds and localities. Comparing the expectation of life at age 1 (e1) of the two populations divided by breeds or localities, there was significant difference in the e1 among different localities but not among different breeds. These facts suggest the existence of some factors which may influence the life span of cats among different localities.  相似文献   
3.
DAS-ELISA proved to be reliable enough to detect a latent infection by Tomato spotted wilt virus (TSWV) in asymptomatic stock plants of chrysanthemum. A high density of Frankliniella occidentalis, the predominant vector, in the presence of latently infected stock plants resulted in a high incidence of disease in the chrysanthemum production field. The incidence of disease was low when the vector thrips were not abundant in spite of the presence of latently infected stock plants. These results suggest that an infestation of the vector thrips causes severe secondary spread of TSWV originating from latently infected stock plants in chrysanthemum production fields. Received 27 July 2001/ Accepted in revised form 27 November 2001  相似文献   
4.
We investigated the synthesis and herbicidal activity of optically active cinmethylin, its enantiomer, and C3-substituted cinmethylin analogs. Optically active cinmethylin could be obtained in seven steps with the Sharpless asymmetric dihydroxylation of α-terpinene. The synthesized cinmethylin and its enantiomer showed similar herbicidal activity, which was independent of the stereochemistry. Next, we synthesized cinmethylin analogs with various substituents at the C3 position. We found that analogs with methylene, oxime, ketone, or methyl groups at the C3 position show excellent herbicidal activity.  相似文献   
5.
Genetic parameters for sow stayability were estimated from farrowing records of 10,295 Landrace sows and 8192 Large White sows. The record for sow stayability from parity k to parity k + 1 (k = 1, …, 6) was 0 when a sow had a farrowing record at parity k but not at parity k + 1, and 1 when a sow had both records. Heritability was estimated by using single-trait linear and threshold animal models. Genetic correlations among parities were estimated by using two-trait linear–linear and single-trait random regression linear animal models. Genetic correlations with litter traits at birth were estimated by using a two-trait linear–linear animal model. Heritability estimates by linear model analysis were low (0.065–0.119 in Landrace & 0.061–0.157 in Large White); those by threshold model analysis were higher (0.136–0.200 & 0.110–0.283). Genetic correlations among parities differed between breeds and models. Genetic correlation between sow stayability and number born alive was positive in many cases, implying that selection for number born alive does not reduce sow stayability. The results seem to be affected by decisions on culling made by farmers.  相似文献   
6.
Using target and reference fattened steer populations, the performance of genotype imputation using lower‐density marker panels in Japanese Black cattle was evaluated. Population imputation was performed using BEAGLE software. Genotype information for approximately 40 000 single nucleotide polymorphism (SNP) markers by Illumina BovineSNP50 BeadChip was available, and imputation accuracy was assessed based on the average concordance rates of the genotypes, varying equally spaced SNP densities, and the number of individuals in the reference population. Two additional statistics were also calculated as indicators of imputation performance. The concordance rates tended to be lower for SNPs with greater minor allele frequencies, or those located near the ends of the chromosomes. Longer autosomes yielded greater imputation accuracies than shorter ones. When SNPs were selected based on linkage disequilibrium information, relative imputation accuracy was slightly improved. When 3000 and 10 000 equally spaced SNPs were used, the imputation accuracies were greater than 90% and approximately 97%, respectively. These results indicate that combining genotyping using a lower‐density SNP chip with genotype imputation based on a population of individuals genotyped using a higher‐density SNP chip is a cost‐effective and valid approach for genomic prediction.  相似文献   
7.
8.
The mammalian uterus changes dramatically during the estrous cycle, pregnancy, and involution post partum. Dynamic changes in the uterine endometrium are a type of homeostasis and proceed with proliferation and exclusion of cells. Homeostasis of the uterus is closely related to apoptosis involving various hormones and cytokines. The objective of the present study was to determine the morphological features and occurrence of apoptosis in the porcine endometrium during the estrous cycle, early pregnancy, and post partum. Cyclic changes in the morphology of the surface epithelium were observed during the estrous cycle. The heights of surface epithelia were significantly high on day 4 of the estrous cycle and the early pregnancy. The heights of the surface epithelium remained low from days 1 to 31 post partum. We then used terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end-labeling (TUNEL) of the 3'-terminal of fragmented DNA, which is effective for detection of apoptosis in various tissues. We found that apoptosis in the porcine endometrium contributed to homeostasis of the endometrium during the estrous cycle through control of cell proliferation and exclusion. Conversely, apoptosis on days 4 and 8 of gestation before the implantation window depended on the plasma estrogen and progesterone levels; however, suppressive homeostasis of apoptosis occurred at the time of implantation on days 15, 18 and 21 of gestation. Our study is the first to demonstrate apoptotic cell death in the porcine endometrium directly by TUNEL method. The results strongly suggest that uterine homeostasis is mainly controlled by apoptosis during the estrous cycle and early pregnancy.  相似文献   
9.
<正>Dear Editor,Rice is an important staple food crop in Asia, but the anaerobic soil conditions in rice fields cause emission of the potent greenhouse gas, methane(CH4)(Le Mer and Roger,2001), and promote the accumulation of arsenic(As) in the grain(Le Mer and Roger, 2001; Khanam et al., 2020).To facilitate sustainable agriculture, using wastewater as an organic fertilizer is essential for reducing wastewater treatment-associated energy consumption and the recycling of wastewate...  相似文献   
10.
Journal of Plant Diseases and Protection - Three isolates of chrysanthemum white rust fungus, Puccinia horiana, were collected from two regions in Hiroshima Prefecture, Japan, in 2017. In an in...  相似文献   
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