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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.
A 12-year-old Thoroughbred gelding exhibited a unilateral exophthalmos on the left side. There had been no other clinical symptoms, such as rhinorrhea, before the first consultation. Clinical, hematologic, plasma biochemical, cytologic, and computed tomography (CT) examinations and complete necropsy were performed. These examinations did not reveal neoplastic lesions. CT images suggested that maxillary and frontal sinuses may have been filled with fluid. Cytologic and pathologic examinations revealed that the maxillary and orbital bones were pushed up with a large amount of the inflammatory fluid effused by chronic sinusitis. The CT and cytologic examinations were of great use for differential diagnosis in this case. This was an unusual case of exophthalmos induced by deformation of the orbital bones resulting from chronic sinusitis.  相似文献   
3.
Amaranthus leaf mottle virus (AmLMV) was classified as a member of the genus Potyvirus on the basis of its particle morphology, serology, and biological properties (Casetta et al., 1986). Based on these properties, an Amaranthus viridis-infecting virus isolated in Spain, causing mottle and leaf blistering as well as reduced growth has been identified as AmLMV. The 3′ terminal genomic region of this and a reference isolate from Italy has been sequenced and reveals a 95% nucleotide identity between the two isolates. The sequenced part comprises the coat protein with 281 amino acids and 315 nucleotides of the 3′ untranslated region (UTR) preceding a polyadenylated tail. Pairwise comparisons and phylogenetic analysis of the nucleotide and deduced amino acid sequences of the CP and 3′ UTR of the cloned cDNAs with those of other potyviruses shows that AmLMV is a distinct potyvirus closely related to Potato virus Y.  相似文献   
4.
The antimicrobial activity of ethanol, acetone and aqueous extracts of the aerial parts of Pseudognaphalium moritzianum was evaluated. Ethanol and acetone extracts showed activity against Staphlococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa. The aqueous extract was active against S. aureus and P. aeruginosa.  相似文献   
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The objective of the present research was to study the inheritance of reduced plant height in the sunflower line Dw 89. Plants of the cytoplasmic male sterile version of this line, cmsDw 89 (mean plant height of 47.4 cm) were crossed with plants of the restorer line RHA 271 (mean of 120.9 cm). F1 plants averaged 120.4 cm, which indicated dominance of standard over reduced plant height. F2 plants followed a segregation pattern of 1 : 15 (reduced : normal height), suggesting that reduced plant height in Dw 89 is controlled by alleles at two loci, designated Dw1 and Dw2. Class assignment in the F2 was confirmed through the evaluation of the F3 generation. Backcrosses to Dw 89 segregated with 1 : 3 (reduced : normal height) ratios, which confirmed the digenic inheritance of the trait. The evaluation of plant height distributions in F3 families suggested possible genetic interaction between the Dw1 and Dw2 loci.  相似文献   
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Zero erucic acid germplasm of Ethiopian mustard is characterized by high levels of linolenic acid (about 21%). Two genetic sources of low linolenic acid (N2‐4961 and HF‐186, about 5%), have been developed in a high erucic acid background. The objectives of this research were to study the genetic relationship between the two low linolenic acid lines and to transfer the trait to zero erucic acid germplasm. F1 seed generations from crosses between both lines had higher average linolenic acid concentration than both parents. F2 seeds segregated for linolenic acid content following a continuous variation from 1.8 to 7.4%, exceeding the limits of the parental distribution ranges. Transgressive recombinants with very low linolenic acid concentration (0.7‐2.7%) were confirmed in the F3 seed generation. The results suggested that N2‐4961 and HF‐186 possess alleles for low linolenic acid at different loci. Transgressive low linolenic acid F3 plants were crossed with plants of a zero erucic acid line and a selection for zero erucic, low linolenic acid was conducted. As a result, a zero erucic acid F3:4 line containing 1.5 ± 0.7% linolenic acid was developed.  相似文献   
9.
The influence of type and concentration of carboxymethyl cellulose (CMC) on flavor and textural properties of custard desserts was examined. A synthetic strawberry flavor mixture was used to flavor the custards; it comprised 15 volatile flavor compounds. The viscosity of the custards was determined using rheometric measurements. Static headspace gas chromatography and in-nose proton transfer reaction-mass spectrometry analyses were conducted to determine the custards' volatile flavor properties. Perceived odor, flavor, and textural properties were assessed in sensory analysis experiments using magnitude estimation against a fixed modulus. Both type and concentration of CMC altered the viscosity of the custards. Softer custards had higher static headspace flavor concentrations. On the contrary, firmer custards demonstrated higher in-nose flavor concentrations. In sensory analysis, firmer custards showed higher thickness and lower sweetness intensities than their low-viscosity counterparts. The thickness perception corresponded to the viscosity of the custards. Removal of sucrose from the custards affected sweetness intensity only and not the intensity of other attributes. Therefore, the influence of the viscosity of the custards on the release of sweet-tasting components is held responsible for the effect on perceived sweetness intensity. Odor intensities were generally higher for the low-viscosity custard, whereas fruity flavor intensities were higher for the firmer custards. Odor intensities correlated with static headspace concentrations and flavor intensities related reasonably well with in-nose concentrations. Opening and closing of the nasal cavity is regarded as an important factor determining the discrepancy between static and in-nose measurements.  相似文献   
10.
Effect of red grapes co-winemaking in polyphenols and color of wines   总被引:1,自引:0,他引:1  
The red grapes co-winemaking effect on phenolic fraction and wine color has been studied for the first time, where Monastrell was comacerated and cofermentated with Cabernet Sauvignon and Merlot. Changes in the relative abundance of anthocyanins were observed as well as hyperchromic shifts at 530 and 620 nm; these effects remain constant after aging. Co-winemaking also favored copigmentation, giving way to more stable anthocyanins and facilitating their polymerization. With regard to color evolution, the mixture of Monastrell with Merlot grapes was more appropriate than with Cabernet Sauvignon for aging wines in oak barrels. The extent of copigmentation was more important in young wines than in aged wines. This is mainly due to the self-anthocyanin monomer reactions in the case of young wines, whereas in aged wines copigmentation is mainly due to the reaction between the anthocyanins and other polyphenolic cofactors. Discriminant analysis showed the possibility of differentiating wines according to the aging time and the type of wine, with color parameters (color intensity, OD 620 nm, and OD 520 nm) being the most important discrimination variables in the first case and petunidin-3-glucoside and peonidin-3-glucoside contents in the second case.  相似文献   
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