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51.
This experiment was carried out to determine the proximate composition of the mid-gut gland (MGG) of the Japanese scallop Patinopecten yessoensis to evaluate the characteristics of divalent minerals and water-soluble protein at various pHs, and to examine Cd-binding protein at different molecular weights. MGG of scallop contained protein, fat and ash of 28.9 g/100 g dry matter, 44.6 g/100 g dry matter and 6.78 g/100 dry matter, respectively. MGG also contained the macrominerals sodium, potassium, magnesium and calcium, and the trace minerals iron, zinc, cadmium and copper. The solubility of divalent minerals and water-soluble protein was high in both acidic and alkaline conditions, except that magnesium was not affected by acidity. The solubility of copper and iron had a positive correlation with water-soluble protein at all pH values, whereas cadmium had a strong correlation at alkaline pH. Low-molecular-weight water-soluble protein (fraction III, 437.5 < MW < 1,355) bound cadmium strongly in acidic, neutral and alkaline conditions. However, in acidic conditions cadmium had the strongest binding to protein.  相似文献   
52.
Considerable evidence indicates that a stimulus that is subthreshold, and thus consciously invisible, influences brain activity and behavioral performance. However, it is not clear how subthreshold stimuli are processed in the brain. We found that a task-irrelevant subthreshold coherent motion led to a stronger disturbance in task performance than did suprathreshold motion. With the subthreshold motion, activity in the visual cortex measured by functional magnetic resonance imaging was higher, but activity in the lateral prefrontal cortex was lower, than with suprathreshold motion. These results suggest that subthreshold irrelevant signals are not subject to effective inhibitory control.  相似文献   
53.
The applicability of sap flux (Fd) measurements to bamboo forests has not been studied. This study was undertaken to establish an optimal and effective design for stand-scale transpiration (E) estimates in a Moso bamboo forest. To this aim, we validated Fd measurements in Moso bamboos in a cut bamboo experiment. In addition, we analyzed how sample sizes affect the reliability of E estimates calculated from Fd and conducting culm area (AS_b). In the cut bamboo experiments, we found that Fd measurement using a 10 mm probe was a valid means of determining the water-use behavior of a Moso bamboo, although a specific correction was needed. Furthermore, we calculated E from stand AS_b (AS_stand) and mean stand Fd (JS). Employing Monte Carlo analysis, we examined potential errors associated with sample size in E, AS_stand, and JS using an original dataset with AS_b and Fd measured for 40 and 16 individuals, respectively. Consequently, we determined the optimal sample size for both AS_stand and JS estimates as 11. The optimal sample sizes for JS were almost the same under different vapor pressure deficit and soil moisture conditions. The optimal sample size for JS at the study site was less than that of a coniferous plantation in the same region probably owing to small individual-to-individual variations in sap flux in the Moso bamboo forest. Our study concludes that sap flux measurements are an applicable technique for assessing water use in Moso bamboo forests.  相似文献   
54.
To be profitable, producers must reduce diet costs, which can be as high as 80% of the variable costs of an aquaculture expense. As vitamin and mineral premixes represent a significant cost, eliminating addition of these premixes could reduce diet costs if no adverse effects were observed for growth and production parameters. A 105‐day feeding trial was conducted with juvenile Australian red claw crayfish (Cherax quadricarinatus) to evaluate the effects of growth, survival, body composition, processing traits and water quality when red claw were fed a supplemental diet containing 28% crude protein (CP) without vitamin and mineral premixes (and supplemented alfalfa hay) compared with red claw fed a diet (control diet) containing 42% CP, vitamin and mineral premixes, and with supplemented alfalfa hay, and compared with red claw only fed alfalfa hay when grown in ponds. Juvenile red claw (mean weight of 15.7 ± 1.0 g) were randomly stocked into nine 0.02‐ha ponds at a rate of 640 per pond (3.2 per m2), and each treatment was used in three ponds. There were two feedings per day, each consisting of one‐half of the total daily ration. At harvest, individual weight, percentage weight gain, specific growth rate, survival and total yield of red claw fed a control diet was significantly higher (P < 0.05) (83.0 g, 398%, 1.53% day?1, 65.1%,and 1708 kg ha?1 respectively) compared with red claw only fed alfalfa hay (44.9 g, 202%, 1.04% day?1, 30.3% and 431 kg ha?1, respectively), but not different (P > 0.05) from red claw fed the supplemental diet without vitamin and mineral premixes (76.2 g, 367%, 1.47% day?1, 57.2% and 1378 kg ha?1). There were no significant differences (P > 0.05) in feed conversion ratio (FCR) among treatments, which averaged 5.0 (based on prepared diet input). These results indicate that vitamin and mineral supplementation in a diet is not necessary when diet containing 28% CP and alfalfa hay are used in combination for pond grown red claw. These results may help reduce diet costs and possibly increase producers’ profits which might allow for industry expansion.  相似文献   
55.
   通过田间试验研究4种有机废弃物中的KEON(KC1可提取态氮)和PEON(磷酸缓冲液可提取态氮)2种形态的有机氮对菜用毛豆生长及化肥氮利用率的影响.结果表明:施用鸡粪和豆粕混合肥与单施化肥相比,地上部分干物质重分别提高20.4%和33.2%,籽粒中的蛋白质含量分别提高17.8%和16.2%.达到显著差异水平;与单施化肥相比,毛豆产量分别提高38.0%和32.5%.有机肥中的KEON和PEON与化学氮肥利用率呈正相关,其相关系数分别达到0.88和0.87(P<0.05).与单施化肥相比,施用鸡粪和豆粕混合肥的当季化学氮肥利用率可分剐提高94.9%和67.4%.  相似文献   
56.
In this study, we investigated the effects of administration of coumestrol during pregnancy on calcium (Ca) metabolism in post-delivery maternal and neonatal mice. From 6.5 to 16.5 days post coitus (dpc), pregnant females were administered daily doses of coumestrol (200 microg/kg body weight/day). One day after parturition, blood samples and the kidneys, liver, jejunum and duodenum were obtained from each of maternal mouse, and blood samples and the kidneys and liver were obtained from neonatal mice. Coumestrol did not have any significant effect on the Ca and inorganic phosphorus concentrations in the sera of the maternal and neonatal mice. No notable effects of coumestrol were observed in relation to Vitamin D receptor expression in the maternal and neonatal mice by immunohistochemical analysis. Coumestrol did not affect the Vitamin D receptor and epithelial calcium channel and 2 mRNA levels in any of the organs investigated. Enzyme histochemical analysis showed that coumestrol decreased intestinal alkaline phosphatase activity in the maternal jejunum and duodenum. In the duodenum, coumestrol decreased expression of intestinal alkaline phosphatase, c-fos and vascular endothelial growth factor at the mRNA level. However, we did not observe any significant effects of coumestrol on the expression of these genes. In conclusion, coumestrol decreased intestinal alkaline phosphatase activity in the small intestines of maternal mice at the level used in the present study, and the mechanisms underlying this effect are different for the jejunum and duodenum.  相似文献   
57.
This retrospective study aimed to evaluate factors associated with survival and to compare characteristics between tumour localizations in dogs with urinary transitional cell carcinoma (TCC) that underwent whole‐body computed tomography (CT) at diagnosis. Dogs with histologically confirmed TCC that received medical therapy between 2010 and 2017 were included; dogs that underwent surgery or radiotherapy for the primary tumour were excluded. According to the CT findings, primary tumour localization (classified into the Bladder, Urethra and Bladder and Urethra groups), prostate involvement, iliosacral lymphadenomegaly, sternal lymphadenomegaly and metastasis to the bone and lung were evaluated for survival analysis. CT at diagnosis revealed iliosacral lymphadenomegaly, sternal lymphadenomegaly, bone metastasis and lung metastasis in 47.7%, 18.5%, 24.6% and 35.4% of the 65 included dogs, respectively. The overall median survival time was 196 days. On multivariable analysis, TCC localization (hazard ratio [HR], 1.90; P = .037), bone metastasis (HR, 2.76; P = .013) and sternal lymphadenomegaly (HR, 3.56; P = .004) were significantly associated with survival. Compared to the Bladder group (n = 16), the Urethra group (n = 26) had higher metastasis rates to the bone (6.3% vs 42.3%; P = .045) and lung (6.3% vs 46.2%; P = .022). The survival time was shorter in the Urethra group than in the Bladder group (121.5 vs 420 days; P < .001), and it was similar only in female dogs (247 vs 420 days; P = .031). These findings suggest that whole‐body CT could be valuable for predicting the prognosis in urinary TCC.  相似文献   
58.
59.
The present study aimed to assess the effect of polymorphisms in the tumor necrosis factor α (TNF-α) promoter (A/A, A/G and G/G) and exons (T/T, T/C and C/C) on immune function and reproductive performance in dairy cows. The occurrence of the first postpartum ovulation within 3 weeks in the cows with the TNF-α promoter A/G and G/G genotypes was higher than in the A/A group. Among the different TNF-α exon genotypes, the occurrence of early first postpartum ovulation was higher in the T/C and C/C genotype groups than in the T/T group. Single nucleotide polymorphisms (SNPs) in the TNF-α gene did not affect the rate of artificial insemination (AI) or duration from parturition to next conception (days open). The apoptosis rate of polymorphonuclear leukocytes (PMNs) did not differ among the TNF-α promoter genotypes, but the PMN transmigration rate was significantly higher for the A/A and A/G genotypes than for the G/G genotype. Interleukin 8 (IL-8) mRNA expression in PMNs and peripheral blood mononuclear cells (PBMCs) before culture was significantly higher for the A/A genotype compared with the G/G genotype. There were no significant differences between the genotypes in the mRNA expression of TNF-α, IL-6, IL-1β, and toll-like receptor 4 (TLR4) in PMNs and PBMCs before and 4 h after culture. IL-8 and IL-1β production by PBMCs cultured for 4 h was significantly higher for the animals with the A/A genotype than for those with the G/G genotype. On the other hand, no significant difference was observed in IL-8 and IL-1β production by PMNs among different TNF-α genotypes. Taken together, these results suggest that SNP in the TNF-α gene affects immune function and reproductive performance in dairy cows.  相似文献   
60.
Regiospecific profiles of fatty acids (FA) of triacylglycerols (TAG) and phospholipids (PL) isolated from red and black rices were investigated. The lipids extracted from red and black rices were separated by thin‐layer chromatography (TLC) into eight subfractions, respectively. With a few exceptions, the major lipid components were TAG (76.4–80.5%), free FA (7.2–9.8%), and phospholipids (3.5–3.6%), while hydrocarbons, steryl esters, diacylglycerols (1,3‐DAG and 1,2‐DAG), and monoacylglycerols were present in minor proportions (0.1–4.1%). The PL components isolated from the two cultivars were phosphatidyl choline (52.3–53.7%), phosphatidyl ethanolamine (22.3–23.1%), phosphatidyl inositol (20.6–21.3%), and others (<3.4%). No significant differences (P < 0.05) in FA distribution were found when these cultivars were compared. The principal characteristics of the FA distribution in the TAG and PL were evident in the rices between the two cultivars: unsaturated FA were predominantly located at the sn‐2 position (77.3–96.8%), while saturated FA primary occupied the sn‐1 or the sn‐3 position (35.0–78.7%) in these lipids. The results of this study could provide useful information to both consumers and producers during manufacture of traditional rice foods in Japan.  相似文献   
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