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41.
Masayuki?Takahashi Takeshi?Yamamoto Sanae?Kato Kunihiko?KonnoEmail author 《Fisheries Science》2005,71(3):662-671
ABSTRACT: The effect of salt concentration on the thermal denaturation profile of myosin in walleye pollack and carp myofibrils was compared by studying the subfragment-1 (S-1) and rod denaturation rates upon heating. Species-specific denaturation mode observed at 0.1 M KCl was no longer detected when samples were heated above 0.5 M KCl, where S-1 and rod denaturation rates were identical to each other. As the heating of the chymotryptic digest of myofibril formed practically no rod aggregates, S-1 denaturation in a form of myosin was the rate limiting step for rod aggregate formation. As the aggregate formation by rod was remarkably suppressed by lowering the temperature, the free movement of myosin tail upon heating was suggested to play an important role in the rod aggregate formation in a high salt medium. 相似文献
42.
T Shimizu T Takahata M Kato 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(2):191-197
Both Mycoplasma gallisepticum (MG) and M. synoviae (MS) antigens prepared for the routine haemagglutination inhibition (HI) test were diluted and absorbed to the separate pieces of durapore membrane for the measurement of dot-immunobinding (DIB) titers of test sera. Besides, durapore strips bearing both antigens were employed for a DIB test with chicken sera definitely diluted 100-fold. Shortening of reaction time of chicken sera with antigens as well as with the secondary serum markedly eliminated non-specific DIB reactions exhibited at low dilutions although the same condition was not so effective on the elimination of non-specific reactions among rabbit hyperimmune sera. Rapid and specific development of DIB antibody which continued at high titer up to 1:640 for 10 weeks postinoculation was proved in the sera of SPF chickens inoculated with MG or MS, while DIB titers of sera from uninoculated chickens remained 1:20 or lower. Non-specific reactions, which occurred in the routine serum plate agglutination test with a part of sera from the inoculated chickens, were not exhibited in the DIB as well as in the HI test with the same sera. Results of the DIB test with serum samples from 287 conventionally reared chickens definitely diluted 100-fold coincided with the results of HI test at a level of 90% with MG and 89% with MS antigen. This technique seems to be useful for a rapid, simple and specific diagnosis of avian mycoplasmosis. 相似文献
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46.
The pathology of Johne''s disease in sheep 总被引:4,自引:0,他引:4
The clinical, gross and histopathological findings in 50 sheep affected with Johne's disease are described. Clinically 90% were emaciated and 20% showed severe diarrhoea. On necropsy there was thickening of the walls of the intestines, particularly of the ileum, caecum and less frequently the jejunum, but in 36% of sheep the changes were only mild. Histologically there was a granulomatous enteritis, typhlitis and colitis, with the most severe changes in the terminal ileum. High numbers of acid-fast organisms were present in the terminal ileum in over 70% of sheep. Mycobacterium paratuberculosis was cultured from only 8% of the sheep examined. 相似文献
47.
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
48.
Summary Mitochondrial DNA (mtDNA) diversity has been determined in apple landraces and cultivars, based upon restriction fragment length polymorphisms (RFLPs) for several mitochondrial genes. Our analysis includes three cultivars, Golden Delicious, McIntosh and Delicious, which represent the various patterns of mtDNA polymorphisms previously described (Ishikawa et al., 1992). A total of five RFLPs were detected, allowing classification of the apple genotypes into four cytoplasmic groups: GroupI, Golden Delicious-type; GroupII, McIntosh-type; GroupIII, Delicious-type; and Group IV, Dolgo Crab-type. European landraces and cultivars were assigned to Groups I, II, and III, while chinese crab apples were placed in either Group III or IV. 相似文献
49.
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
50.
Simplified culture method of detached ears and its application to vernalization in wheat 总被引:3,自引:0,他引:3
Summary The effects of the addition of sulfurous acid into culture solution and of cold treatment of the solution were examined to simplify the culture of detached wheat ears. In the simplified method, detached ears could be cultured at room temperature on the liquid medium containing 100 g/l sucrose and 0.075% sulfurous acid without any sterilization. The immature seeds in detached ears cultured by this method were treated with low temperature or with chemicals known to have vernalizing effect. The chemical treatment did not affect the chilling requirement of immature embryos, although photoperiodic response and narrow-sense earliness were reduced by kinetin and trypsin. The low temperature treatment drastically affected the chilling requirement, and fully vernalized mature seeds having normal germinability were obtained by treating the detached ears in culture with low temperature from 10 days after anthesis. 相似文献