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91.
Elastomeric proteins occur in the shell ligament of bivalve molluscan shellfish. A newly identified protein named ligament protein-1, with a molecular mass of approximately 12 kDa, was extracted from the shell ligament of the scallop, Patinopecten yessoensis, with 70 % formic acid, and purified by gel filtration column chromatography and reverse-phase C18 column chromatography. Although the amino acid composition of this protein differs from that of the known shell ligament protein abductin, the partial amino acid sequences are similar to those of abductin. CD spectra and FT–IR spectra analyses showed that ligament protein-1 retains its secondary structures of α-helix, β-turn, and β-sheets. To the best of our knowledge, this is the first study on protein purification from the shell ligament of a bivalve molluscan shell.  相似文献   
92.
The effect of irradiance and temperature on the photosynthesis of two Japanese agarophytes, Gelidium elegans and Pterocladiella tenuis (Gelidiales), was determined using dissolved oxygen sensors and pulse amplitude modulated (PAM) fluorometry. Gross photosynthesis and dark respiration rates were determined over a range of temperatures (8–36 °C). The highest gross photosynthetic rates were 40.3 and 37.0 mg O2 g ww ?1  min?1 and occurred at 24.3 and 25.5 °C [95 % Bayesian credible interval (BCI) 20.7–28.0 and 23.4–28.3 °C], respectively. The dark respiration rate in G. elegans and P. tenuis increased with increasing temperature at a rate of 0.10 and 0.31 mg O2 g ww ?1  min?1 °C?1 , respectively. Modeling the net photosynthesis–irradiance (PE) responses of G. elegans and P. tenuis at 20 °C revealed that the net photosynthetic rates quickly increased at irradiance levels below the estimated saturation irradiance of 88 and 83 µmol photons m?2 s?1, with a compensation irradiance of 14 and 19 µmol photons m?2 s?1, respectively. The highest value of the maximum effective quantum yield (Φ PSII) occurred at 20.1 °C (BCI 18.9–21.5 °C) and 21.3 °C (BCI 20.2–22.5 °C) for G. elegans and P. tenuis and was 0.49 and 0.45, respectively. These optimal temperatures of Φ PSII were relatively lower than those determined by the photosynthesis–temperature model of oxygen evolution. The temperature response of these species indicates that they are probably well adapted to the current range of seawater temperatures in the study site but that they are near the boundary of their tolerable limits.  相似文献   
93.
Although MRI has become widely used in small animal practice, little is known about the validity of advanced MRI techniques such as diffusion‐weighted imaging and diffusion tensor imaging. The aim of this retrospective analytical observational study was to investigate the characteristics of diffusion parameters, that is the apparent diffusion coefficient and fractional anisotropy, in dogs with a solitary intracranial meningioma or histiocytic sarcoma. Dogs were included based on the performance of diffusion MRI and histological confirmation. Statistical analyses were performed to compare apparent diffusion coefficient and fractional anisotropy for the two types of tumor in the intra‐ and peritumoral regions. Eleven cases with meningioma and six with histiocytic sarcoma satisfied the inclusion criteria. Significant differences in apparent diffusion coefficient value (× 10?3 mm2/s) between meningioma vs. histiocytic sarcoma were recognized in intratumoral small (1.07 vs. 0.76) and large (1.04 vs. 0.77) regions of interest, in the peritumoral margin (0.93 vs. 1.08), and in the T2 high region (1.21 vs. 1.41). Significant differences in fractional anisotropy values were found in the peritumoral margin (0.29 vs. 0.24) and the T2 high region (0.24 vs. 0.17). The current study identified differences in measurements of apparent diffusion coefficient and fractional anisotropy for meningioma and histiocytic sarcoma in a small sample of dogs. In addition, we observed that all cases of intracranial histiocytic sarcoma showed leptomeningeal enhancement and/or mass formation invading into the sulci in the contrast study. Future studies are needed to determine the sensitivity of these imaging characteristics for differentiating between these tumor types.  相似文献   
94.
Otitis externa in 27 toy poodles and 40 miniature dachshunds was treated using a video otoscope. A distinct concavity (external tympanic concavity) was observed at the junction between the ventral part of the external surface of the tympanum and the ear canal to which a considerable amount of hair and debris had adhered. All hair and debris adhering to the external tympanic concavity were removed, and systemic antibiotic and antifungal agents were administered, after which all of the dogs recovered. The pattern of hair growth observed in the external tympanic concavity could be characterized according to the breed of dog. All of the toy poodles presented with curly hairs, while the miniature dachshunds had upright or flat-lying hairs.  相似文献   
95.
Lipid A, the active component of lipopolysaccharide (LPS), exists in the outer membrane of Gram-negative bacteria and binds to the Toll-like receptor 4 (TLR4) and MD-2 complex. On the other hand, the synthetic precursor of Escherichia coli lipid A, tetraacylated lipid IVa, is an agonist for TLR4 and MD-2 complex in murine, equine and feline cells but is an antagonist for lipid A in human cells. The aim of the study was to examine the function of canine Toll-like receptor 4 (TLR4) and MD-2 complex on canine blood mononuclear cells (BMC), by analyzing lipid A- or lipid IVa-induction of TNF-α production from these cells in order to understand canine innate immune system. After 5-h culture of canine BMC with lipid A (lipid A culture) or lipid IVa (lipid IVa culture), the TNF-α, as determined by ELISA, had increased in the supernatants of the lipid A cultures in a dose-dependent manner, whereas the TNF-α was undetectable in supernatant of lipid IVa-treated cultures. The TNF-α was statistically significantly different between the lipid A and lipid IVa cultures (100 and 1000 ng/ml). TNF-α production from canine BMC was inhibited, in a lipid IVa-dose-dependent manner, when the BMC were pre-cultured with lipid IVa for 60 min and then cultured with lipid A for 5h, while in control BMC cultures production if TNF-α was unchanged. These results indicate that the TNF-α production stimulated by lipid A was competed out by pre-exposing the BMC to lipid IVa. Thus, lipid A is an agonist for TNF-α production in canine BMC, whereas lipid IVa appears to be an antagonist against this lipid A stimulation of canine BMC.  相似文献   
96.
97.
To elucidate diversity and evolution of the Waxy gene in foxtail millet, Setaria italica, we analyzed sequence polymorphism of Waxy gene in 83 foxtail millet landraces collected from various regions covering the entire geographical distribution of this millet in Europe and Asia. We found a unique geographic distribution pattern at the sequence level of gene haplotypes and also found a large diversity in East Asian landraces. We also found a higher degree of genetic polymorphism in a non-waxy phenotype than in other low amylose types, supporting the hypothesis that low amylose types recently originated from non-waxy type.  相似文献   
98.
Abstract

Co-situs is the placement with one application of a sufficient amount of controlled-release fertilizer for an entire growing season at any site, together with seeds or seedlings, without causing fertilizer salt injury. An experiment was conducted to find an efficient method for ameliorating Fe deficiency in two rice cultivars (cv. Tsukinohikari and cv. Sasanishiki) grown in a calcareous soil (pH 9.2, CaCO3 384 g kg?1), which was poor in organic matter (0.1 g kg?1) and available Fe (3.0 μg g?1 soil). The field treatments consisted of co-situs application of the following fertilizers: 1) controlled-release NPK fertilizer (CRF-NPK) containing no micronutrients; 2) controlled-release NPK fertilizer containing micronutrients (CRF-M1); and 3) controlled-release NPK fertilizer containing micronutrients (CRF-M2). The main difference between CRF-M1 and CRF-M2 was that the former had larger granules than the latter. All the fertilizers were placed in contact with the roots of rice seedlings at transplanting time. Plants in the CRF-M1 and CRF-M2 treatments had similar lengths, number of stems, leaf age, and leaf color (SPAR value) during the cultivation period. By contrast, plants from the CRF-NPK treatments grew poorly, showed severe chlorosis symptoms of Fe deficiency, and all died on 30 DAT. Plants of both cultivars accumulated more macroand micronutrients with the CRF-M2 treatment than with the CRF-M1 treatment. The grain yield of cv. Tsukinohikari was 0.0, 1,910, and 2,160 kg ha?1 for the CRF-NPK, CRF-M1, and CRF-M2 treatments, respectively, and 0.0, 2,490, and 2,860 kg ha?1 for the same treatments for cv. Nihonbare. Chlorosis due to iron deficiency was successfully ameliorated and world-average grain yields were obtained with the co-sites application of both controlled-release fertilizers.  相似文献   
99.
Development of aminopolycarboxylate chelants (APCs) having enhanced biodegradability is gaining increasing focus to replace the EDTA and its homologs with those used widely for the ex situ treatment of contaminated soils and are potential eco-threats. The paper reports the chelant-assisted extraction of the toxic metals (Cd, Cu, Pb, and Zn) from the metal-spiked European reference soils (Eurosoil 1 and Eurosoil 4) using biodegradable APCs, namely EDDS, GLDA, and HIDS. The effects of chelant-to-metal molar ratio, solution pH, and metal/chelant stability constants were evaluated, and compared with that of EDTA. The selectivity aptitude of the biodegradable chelants towards the toxic metals was assumed from the speciation calculations, and a proportionate correlation was observed at neutral pH. Pre- and post-extractive solid phase distributions of the target metals were defined using the sequential extraction procedure and dissolution of metals from the theoretically immobilized fraction was witnessed. The effect of competing species (Al, Ca, Fe, Mg, and Mn) concentrations was proven to be minimized with an excess of chelant in solution. The highlight of the outcomes is the superior decontamination ability of GLDA, a biodegradable APC, at minimum chelant concentration in solution and applicability at a wide range of pH environments.  相似文献   
100.
Six year-old Japanese pear (Pyrus seratina Reheder cv. Kosui) trees grafted on P. serotina cv. Nihonyamanashi were grown in containers filled with Granite Regosol under glasshouse conditions. At different stages of fruit growth, pear trees were exposed to an elevated CO2 concentration (130 Pa CO2 ) along with a control (35 Pa CO2). For one group of plants, CO2 enrichment was applied for 79 d from 52 d after full bloom (DAB) to fruit maturity (long-term CO2 enrichment) and for another group the same treatment was applied for 35 d from 96 DAB to fruit maturity (short-term CO2 enrichment). The effects of the elevated CO2 concentration on vegetative growth, mineral contents, and fruit production and quality were examined. Long-term CO2 enrichment enhanced vegetative growth, without any significant effect on the mineral contents in either flower bud or fruit except for a remarkable increase in the K content. Long-term CO2 enrichment increased the fruit size and fresh weight, but had no significant effect on the fruit quality. On the other hand, the short-term CO2 enrichment did not induce any significant change in the fruit size but increased the fruit sugar concentration. Along with the reduction of the sorbitol concentration in fruit, the fructose and sucrose concentrations increased and these changes occurred earlier at elevated CO2 than at ambient CO2 concentrations. From these results, we concluded that the effect of CO2 enrichment on fruit growth varies depending upon the growth stages of fruit: during the initial and fruitlet stages when fruit expansion occurs, CO2 enrichment increases the fruit size, whereas, during maturation when fruit expansion has slowed down and sugar accumulation in fruit is active, it increases the fruit sugar concentration.  相似文献   
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