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401.
In Arabidopsis, two genes of abscisic acid (ABA) 8′-hydroxylase (cytochrome P450 (CYP) 707A1 and A2) have been found to play important roles in seed dormancy through the regulation of ABA content in seeds. In order to examine the role of wheat ABA 8′-hydroxylase gene in seed dormancy, a diploid wheat ABA 8′-hydroxylase gene was cloned that showed high similarity to a barley ABA8′-hydroxylase gene (HvABA8′OH-2), and the cloned gene was designated as TmABA8′OH-2. Using recombinant inbred lines derived from a cross between diploid wheat Triticum boeoticum L. (Tb) and Triticum monococcum L. (Tm), TmABA8′OH-2 has been mapped to near the centromeric region of the long arm of chromosome 5Am, where the major seed dormancy QTL has been previously found. Comparison of the deduced amino acid sequences of TmABA8′OH-2 between Tb and Tm revealed five amino acid residue substitutions. These amino acid residues have distinctly different characteristics, and one of the substitutions occurs in the highly conserved amino acid residues in CYP707A family, indicating that these substitutions may have effects on the enzyme activities. Moreover, hexaploid wheat TmABA8′OH-2 homologue revealed that the level of its expression during seed development peaks at mid-maturation stage. This resembles the expression pattern of the Arabidopsis CYP707A1, which was shown to control seed dormancy. These results imply a possibility that TmABA8′OH-2 might be involved in seed dormancy, and associated with the QTL on chromosome 5Am.  相似文献   
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403.
Long-lived volcanism on the lunar farside revealed by SELENE Terrain Camera   总被引:2,自引:0,他引:2  
We determined model ages of mare deposits on the farside of the Moon on the basis of the crater frequency distributions in 10-meter-resolution images obtained by the Terrain Camera on SELENE (Selenological and Engineering Explorer) (Kaguya). Most mare volcanism that formed mare deposits on the lunar farside ceased at approximately 3.0 billion years ago, suggesting that mare volcanism on the Moon was markedly reduced globally during this period. However, several mare deposits at various locations on the lunar farside also show a much younger age, clustering at approximately 2.5 billion years ago. These young ages indicate that mare volcanism on the lunar farside lasted longer than was previously considered and may have occurred episodically.  相似文献   
404.
The present study examined the effect of excessive application of farmyard manure (FM) on rice production and environmental pollution in paddy fields of Japan. A long-term field experiment was conducted during the period 1976–2006 to examine the trends of rice yield and yield components as affected by the excessive FM application (20 Mg ha?1 year?1 containing 110 kg N, 180 kg P2O5, and 320 kg K2O). Rice growth, soil fertility, and surface water quality were also assessed in the final year (2006). The results obtained were compared with those of a conventional practice with recommended doses of inorganic fertilizer (IF), i.e. 85 kg N, 68 kg P2O5, and 53 kg K2O ha?1 year?1, and an unfertilized control (CR). The excessive FM application resulted in a gradual decrease in grain yield, which was mostly explained by the reduction of grain fertility under the luxuriant rice growth. This reduction may have been due to the higher accumulation of soil nutrients such as N, P, and K. Moreover, the excessive FM application increased chemical oxygen demand, total P, and soluble K concentrations in the paddy surface water and their effluent loads compared to the conventional practice with the recommended IF application.  相似文献   
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406.
OBJECTIVE: To evaluate effects of dietary carbohydrate on urine volume; struvite crystal formation; and calcium, phosphorus, and magnesium balance in clinically normal cats. ANIMALS: 21 healthy adult cats (15 sexually intact males and 6 sexually intact females). PROCEDURE: Diets containing no carbohydrate source (control diet), control plus starch, or control plus fiber were given in a 3 X 3 Latin-square design. The diets were available ad libitum in study 1 (n = 12) and given under restrictions in study 2 (9) to equalize daily intakes of crude protein among the 3 groups. Formation of struvite crystals and balance of calcium, phosphorus, and magnesium were measured. RESULTS: Urine volume was lower in the starch group and fiber group in study 1, whereas no differences were detected among the groups in study 2. Urinary pH and struvite activity product were higher in the starch group in both studies, and the fiber group also had higher struvite activity product in study 2. In both studies, urinary concentrations of HCl-insoluble sediment were higher in the starch group and fiber group. In the fiber group, a net loss of body calcium, phosphorus, and magnesium was detected in study 2. CONCLUSIONS AND CLINICAL RELEVANCE: Starch and fiber in diets potentially stimulate formation of struvite crystals. Hence, reducing dietary carbohydrate is desirable to prevent struvite urolith formation. In addition, a net loss of body calcium, phosphorus, and magnesium during feeding of the fiber diet suggests that dietary inclusion of insoluble fiber could increase macromineral requirements of cats.  相似文献   
407.
The antigenic properties of Brachyspira (B.) alvinipulli ATCC 51933 and strain C2 were analyzed and compared with those of B. hyodysenteriae ATCC 27164 and ATCC 31212, B. pilosicoli ATCC 51139, B. innocens ATCC 29796 and B. aalborgi NCTC 11492. In gel immunodiffusion tests, a protein in B. alvinipulli ATCC 51933 reacted strongly with anti-B. alvinipulli ATCC 51933-serum and formed two precipitin lines. Furthermore, by an immunoblotting technique, the 105-kilodaltons (kDa) protein in B. alvinipulli ATCC 51933 reacted strongly with each of the antisera to B. hyodysenteriae, B. pilosicoli, B. innocens and B. aalborgi. Therefore, the 105-kDa protein could be applied to diagnosis of chicken infection by B. alvinipulli and B. pilosicoli. But the 105-kDa protein reacting with the anti-B. alvinipulli ATCC 51933-serum was not confirmed in B. hyodysenteriae, B. pilosicoli, B. innocens and B. aalborgi. The N-terminal amino acid sequence of the 105-kDa protein isolated from B. alvinipulli ATCC 51933 was Met-Lys-Lys-Met-Val-Tyr-Phe-Phe-Gly-Asn. The amino acid alignment of this protein possessed 50% homology with the periplasmic-iron-binding protein BitC in B. hyodysenteriae.  相似文献   
408.
The genetic and molecular mechanisms that control the development of capillary blood vessels during follicular development are beginning to be elucidated. Ovarian follicles contain and produce angiogenic factors that may act alone or in concert to regulate the process of thecal angiogenesis. These factors are ultimately controlled by endocrine, paracrine and autocrine regulation. A recent study indicated that vascular endothelial growth factor (VEGF) plays an important role in the process of thecal angiogenesis during follicular development. We are developing a novel technology for the induction of follicular development using the technique of in vivo gene administration. Here, we summarize the recent progress of our research.  相似文献   
409.
Lactoferrin (LF), a member of the transferrin (TF) protein family, is an iron-binding protein that is known to interact with bacteria through a specific receptor. We examined the binding of bovine LF (bLF), bovine TF (bTF), and ovotransferrin (OTF) by Toxoplasma gondii using a fluorescence test and the streptavidin-biotin (SAB) method using biotin-streptavidin, and found that bLF, bTF, and OTF bound to the protein components of T. gondii. Furthermore, we confirmed that bLF, bTF, and OTF bound a 42 kDa soluble protein of T. gondii by far Western blot method. These results demonstrated that bLF binding proteins are present on T. gondii.  相似文献   
410.
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