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1.
Thermal inactivation of Ca2+ ATPase of squid myofibrils was significantly suppressed in the presence of Ca2+. Monomeric myosin content decreased much faster than Ca2+ ATPase inactivation in Ca medium, which was well explained by fast rod denaturation. In contrast, rod denaturation was slower than S-1 in EDTA medium. The decrease in monomeric myosin content was explained by faster S-1 denaturation. Comparing the S-1 and rod denaturation rates at a fixed temperature, it was concluded that S-1 denaturation was suppressed by Ca2+ whereas the rod denaturation was not. An unfolding experiment with isolated myosin rod confirmed that there was no stabilizing effect of Ca2+ on myosin rod. It was concluded that significant stabilization of the S-1 portion by Ca2+ generated the apparently different myosin denaturation patterns in the two media.  相似文献   
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Serum apolipoprotein A-I concentrations in cows infected with Salmonella Typhimurium were evaluated to assess its relevance in salmonellosis. Apolipoprotein A-I has been shown in rats to be secreted by the intestine as well as the liver. Clinical symptoms such as diarrhea revealed an outbreak of salmonellosis in 22 cows on a farm, and sera were obtained at 6 (acute phase), 16, 28 (convalescent period) and 42 d (postconvalescent period) after the outbreak. Apolipoprotein A-I concentrations (mean +/- SD, mg/mL), determined by ELISA, were 0.598 +/- 0.497 (day 6), 0.111 +/- 0.060 (day 16), 0.432 +/- 0.311 (day 28) and 0.727 +/- 0.516 (day 42). Compared with the concentration at day 42, those at 16 and 28 d were significantly (P < 0.01, P < 0.05) lower, but that at day 6 was not. The serum concentration of apolipoprotein B-100 (of liver origin in cattle) was unaltered during the course of salmonellosis. The concentration of apolipoprotein A-I was positively correlated with those of serum total cholesterol (r = 0.589, P < 0.01) and phospholipids (r = 0.590, P < 0.01). These results suggest that apolipoprotein A-I in cattle is in part of intestinal origin, and also that its decreased serum concentration in salmonellosis can be attributed to the reduced intestinal synthesis or secretion of this apolipoprotein. Moreover, as a potential carrier for dietary lipids such as cholesterol, determination of serum apolipoprotein A-I concentration is suggested to be useful when assessing the nutritional status of the affected cows.  相似文献   
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To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned and reddish in appearance; had lesions predominantly in the cranial, middle and accessory lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions, no significant differences were noted between the challenge and control groups regarding mean rectal temperature and daily weight gain. These results provide useful insights into the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in piglets, which differ from findings in reported field cases.  相似文献   
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OBJECTIVE: Little is known about the relationship of monetary diet costs to dietary intake and obesity, particularly in non-Western populations. This study examined monetary cost of dietary energy in relation to diet quality and body mass index (BMI) among young Japanese women. DESIGN: Dietary intake was assessed by a validated, self-administered, diet history questionnaire. Diet costs were estimated using retail food prices. Monetary cost of dietary energy (Japanese yen 1000 kcal-1) was then calculated. BMI was computed from self-reported body weight and height. SUBJECTS: A total of 3931 female Japanese dietetic students aged 18-20 years. RESULTS: Monetary cost of dietary energy was positively associated with intakes of fruits, vegetables, fish and shellfish, and pulses; however, higher monetary cost of dietary energy was also associated with higher consumption of fat and oil, meat and energy-containing beverages, and lower consumption of cereals (rice, bread and noodles) (all P for trend <0.01). At the nutrient level, monetary cost of dietary energy was positively associated with intakes of dietary fibre and key vitamins and minerals, but also associated positively with intakes of fat, saturated fatty acids, cholesterol and sodium, and negatively with carbohydrate intake (all P for trend <0.0001). After adjustment for possible confounders, monetary cost of dietary energy was quite weakly but significantly negatively associated with BMI (P for trend = 0.0197). CONCLUSIONS: Increasing monetary cost of dietary energy was associated with both favourable and unfavourable dietary intake patterns and a quite small decrease in BMI in young Japanese women.  相似文献   
7.
The movements of 28 adult chum salmon, Oncorhynchus keta (Walbaum) tagged with electromyogram (EMG) transmitters were tracked along the Toyohira river, Hokkaido, Japan, in October of 2007 and 2008 to investigate and evaluate the upstream migratory behavior through the protection bed and fishway of ground sills. The approach time of fish that ascended successfully through the protection bed and fishway was shorter than that of unsuccessful fish. The unsuccessful fish were observed to swim in currents with high water velocity and shallow water depth at swimming speeds that exceeded their critical swimming speed (U crit) during the approach to these structures. In consequence, unsuccessful fish frequently alternated between burst and maximum sustained speeds without ever ascending the fishway, and eventually became exhausted. It is important that fishway are constructed to enable chum salmon to find a passage way easily, so that they can migrate upstream rapidly without wasting excessive energy.  相似文献   
8.
Digestion of carp myofibrils at 30 degrees C in 0.5 M KCl medium with calcium ion generated unique 135 kDa heavy meromyosin (HMM). The HMM was not produced when digested at 10 degrees C. A further digestion of the 135 kD HMM isolated in the absence of calcium ion generated uniquely short subfragment-2 (S-2) with a size of 40 kDa (40 kDa S-2) together with subfragment-1 (S-1). The 40 kDa S-2 was identified by N- and C-end sequencing, and demonstrated to locate the amino end of the rod portion. The unfolding temperature for the 40 kDa S-2 was around 52 degrees C as studied by circular dichroism measurement. The same unfolding peak was also detected with the intact rod together with a large unfolding peak at around 36 degrees C coming from the rest of the rod portion, light meromyosin. The unfolding peak for the 40 kDa S-2 in myosin was a little lower (48 degrees C) than that in free form, suggesting the involvement of the head portion in the stability of the 40 kDa S-2 in the structure.  相似文献   
9.
To utilize lupin seeds for food and pharmaceutical applications, lupin seeds were pretreated to remove oil using hexane or carbon dioxide. Two types of lupin protein isolate were prepared. Both types of protein isolate showed good foaming activity, comparable to egg white. Protein isolate extracted under acid conditions showed higher foaming activity than protein isolate extracted at neutral pH. The lipoxygenase activity was much reduced in both of the protein isolates. The protein isolate extracted at neutral pH showed a stronger angiotensin converting enzyme inhibition than the protein isolate extracted under acidic pH. In contrast, the protein isolate extracted under acid conditions had a greater sodium cholate binding capacity, comparable to that of cholestyramine. Lupin samples showed less DPPH radical scavenging activity than deoiled soybean. The deoiling method did not affect the functional properties, lipoxygenase activity, angiotensin converting enzyme inhibition, sodium cholate binding, and radical scavenging activity.  相似文献   
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