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1.
Using RT-PCR and semi-quantitative PCR, mRNA expression for canine interferon (IFN)-gamma, interleukin (IL)-2, IL-4, IL-5, IL-10, tumor necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta in peripheral blood mononuclear cells (PBMCs) was examined in dogs with or without demodicosis. mRNA expression for IFN-gamma as well as TNF-alpha in dogs with demodicosis (localized (LD) and generalized (GD)) was slightly lower than those in dogs without demodicosis (healthy controls). Expression of IL-5 mRNA in dogs with demodicosis was higher than that in control dogs, but there were no significant differences in IL-4 and IL-10 mRNA expression levels among the three groups. On the other hand, expression levels of TGF-beta mRNA in dogs with GD were higher than those in control dogs and dogs with LD. The expression levels of IL-5 and TGF-beta mRNA decreased in all three dogs with GD which showed resolution of the clinical signs. Taken together, these results suggest that the Th2-like response in PBMCs from dogs with demodicosis is up-regulated, and that subsequent increased expression of IL-5 and TGF-beta mRNA in dogs with GD is reversible after treatment. Therefore, these cytokines, particularly IL-5, might be a useful clinical index of the clinical course in demodicosis. Also, increased TGF-beta mRNA expression might be a key factor for revealing the difference in the mechanism of onset between LD and GD.  相似文献   
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C. M. Lu    B. Zhang    F. Kakihara  M. Kato 《Plant Breeding》2001,120(5):405-410
Fifteen lines of Brassica napus were resynthesized via ovule culture through 24 interspecific crosses between four Brassica oleracea and three Brassica campestris accessions. The degree of success in the interspecific crosses was significantly influenced by maternal genotypes. The interspecific hybrid production rate (HPR) varied with combinations from 0 to 76.9%, with a mean HPR of 24.7% for the crosses with B. campestris as the female parent and 6.9% for the crosses with B. oleracea as female parent. Twenty‐four crosses between seven natural and six resynthesized B. napus gave, on average, 10.3 seeds per pod, and ranged from 1.2 to 22.0 seeds per pod, depending on genotypes of both parents. Resynthesized lines of B. napus showed high erucic acid content and variable content of linolenic acid, ranging from 3.4% to 9.9%. The fatty acid composition in hybrid seeds between natural and resynthesized B. napus was dominated by the embryo genotypes; an additive mode was shown for erucic acid and positive over‐dominance for linolenic acid content.  相似文献   
4.
B. Zhang    C. M. Lu    F. Kakihara  M. Kato 《Plant Breeding》2002,121(4):297-300
The effect of genome composition and cytoplasm on petal colour was studied in Brassica. Three accessions of yellow‐petalled B. rapa (2n= 20, AA) were crossed with a white‐petalled B. oleracea var. alboglabra (2n= 18, CC) and with three cream‐yellow‐petalled B. oleracea var. gongylodes (2n= 18, CC) to produce resynthesized B. napus (2n= 38, AACC or CCAA) and sesquidiploids (2n= 29, AAC or CAA). Petal colour was measured with a Hunter automatic colour difference meter. The results revealed that petal colour in Brassica is controlled by nuclear genes and by cytoplasmic factors. Additive and epistatic gene effects were involved in the action of nuclear genes. When crosses were made between yellow‐petalled B. rapa and white‐petalled B. oleracea var. alboglabra, significant additive, epistatic and cytoplasmic effects were found. White petal colour was partially epistatic over yellow petal colour. When crosses were made between yellow‐petalled B. rapa and cream‐yellow‐petalled B. oleracea var. gongylodes, only epistatic effects were detected. Yellow petal colour was epistatic over cream‐yellow.  相似文献   
5.
Seventy-two accessions covering six varieties of Cucumis melo were characterized by using 35 morphological characters with emphasis on shelf-life, and the relationships between shelf-life and related characters was investigated. Principal component analysis (PCA) revealed that development period of plant and fruit, size of seed and fruit, shelf-life, stem hair, flesh juiciness, netting, abscission of peduncle, rapid yellowing of epidermis at maturity, Brix value, and color of flesh and epidermis etc. were the principal characters to discriminate melon accessions examined in the present study. According to the scatter diagram, vars. acidulusand makuwa, both of which belong to the Oriental melon, are closely related because of their short growth duration, small seed, thin pericarp and poor shelf-life, while American cantaloupe (var.reticulatus) and European cantaloupe (var. cantalupensis) are rather closely related due to their climacteric fruit with orange flesh, slipped peduncle and rapid yellowing of epidermis at maturity, which is closely related with their shelf-life. PCA also indicated that var. saccharinus was closer to var. inodorus than to the other varieties, due to their requirement of long period for development, large size of seed and fruit, and half- or non-slipped peduncle. Shelf-life of melon fruit was significantly correlated with the following characters: quality of flesh, size of seed and fruit, abscission of peduncle, development periods of plant and fruit, rapid yellowing of epidermis at maturity, Brix value and color of flesh and epidermis. Accessions with good shelf-life were mostly found in vars. saccharinus and inodorus. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
6.
Photosynthesis is reversibly inhibited by exposing plants to SO2. The formation of α-hydroxy sulfonate in the exposed plants is suggested as one of the effects, because this compound inhibits glycolic oxidase which is necessary in the glycolic acid pathway. The suppression of the glycolic acid path should affect various aspects of metabolism in plants, particularly the reduction of the biosynthesis of glycine and serine. In this paper, the biosynthesis of these amino acids in plants exposed to SO2 was investigated to estimate the significance of the formation of α-hydroxy sulfonate in the plants. The results show that photosynthetic formation of serine was reduced in the exposed plants, and that α-hydroxy sulfonate was formed.  相似文献   
7.
F1-adenosine triphosphatase (ATPase) is an ATP-driven rotary molecular motor in which the central gamma subunit rotates inside a cylinder made of three alpha and three beta subunits alternately arranged. The rotor shaft, an antiparallel alpha-helical coiled coil of the amino and carboxyl termini of the gamma subunit, deeply penetrates the central cavity of the stator cylinder. We truncated the shaft step by step until the remaining rotor head would be outside the cavity and simply sat on the concave entrance of the stator orifice. All truncation mutants rotated in the correct direction, implying torque generation, although the average rotary speeds were low and short mutants exhibited moments of irregular motion. Neither a fixed pivot nor a rigid axle was needed for rotation of F1-ATPase.  相似文献   
8.
The involvement of metabolic enzymes in the resistance of a laboratory colony of diamondback moth, Plutella xylostella (L), to the neonicotinoid insecticide acetamiprid was determined with the synergists piperonyl butoxide (PBO), which suppresses the activity of cytochrome P-450 monooxygenases, and S,S,S-tributyl phosphorotrithioate (DEF), an inhibitor of esterases, using the leaf-dipping method. Both PBO and DEF enhanced the insecticidal activity of acetamiprid significantly in the resistant P. xylostella strain but not in a reference strain, suggesting that cytochrome P-450 monooxygenases and esterases play an important role in the resistance of P. xylostella to acetamiprid. The resistant P. xylostella strain was also reared without further exposure to acetamiprid to determine the stability of resistance. Maintaining the resistant strain for seven generations in the absence of selection pressure resulted in a drop in resistance ratio from 110 to 2.42, indicating that acetamiprid resistance in P. xylostella is not stable.  相似文献   
9.
This is the first report describing the expression of canine calreticulin (cCRT) in canine mammary gland tumour (MGT). Using cDNA subtraction method, it is found that mRNAs of CRT, cathepsin A, ovostatin, and lactotransferrin were differentially expressed in mammary adenocarcinoma as compared to hyperplasia, both of which were obtained from the dog. Furthermore, the mRNA expression levels of CRT and cathepsin A were significantly higher in canine MGT samples than in nontumour samples. In contrast, immunohistochemical studies have indicated that the expression of cCRT protein found to be detected in most of mammary gland tissues and was not correlated to the types of canine MGTs. Furthermore, cCRT was molecularly cloned, and the amino acid sequence of cCRT was found to be very similar to those of other species. Further studies are required to elucidate additional roles of cCRT in canine MGT.  相似文献   
10.
The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture. In the present study, we described the dietary effect of the squid viscera hydrolysate (SVH) on the growth performance of the red sea bream. The addition of SVH to feed caused significant increases in feed intake, fork length, and body weight and produced a marked improvement in feed conversion after 4 weeks of feeding. Furthermore, the results of this feeding revealed that low dietary levels of SVH promote growth performance in the red sea bream. We physiologically analyzed digestion and appetite in fish fed diet containing SVH. SVH promoted the activity of hepatic trypsin and lipase, gene expression of stomach pepsin, hepatic lipase, and pyloric caeca trypsin, thereby improving the nutrient availability in red sea bream. Moreover, the mRNA expression of appetite regulating factor, such as brain NPY and stomach ghrelin was significantly improved by dietary SVH. Our current results indicate that dietary SVH as alternative material produced excellent effects on growth performance, which is dependent on the promoting effect on digestion and appetite in red sea bream.  相似文献   
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