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991.
The research presented herein provides valuable data with respect to the phosphorus content of starches from many potato (Solanum tuberosum L.) cultivars using an energy-dispersive X-ray fluorescence technique. In all starches examined, the phosphorus content ranged from 308 to 1244 ppm. Furthermore, the estimation of the starch characteristics of representative samples differing manifestly in their phosphorus content indicated that enhancing the starch phosphate resulted in significant increases in the swelling power, peak viscosity, and breakdown and significant but small increases in the onset and peak temperatures of gelatinization. Other starch quality parameters, such as the amylose content, median granule size, and the gelatinization enthalpy, did not change significantly due to the degree of phosphate substitution of starch.  相似文献   
992.
OBJECTIVE: We investigated the pathophysiological significance of molecular forms of adrenomedullin (AM) in patients after the Fontan procedure. METHODS: Plasma concentrations of mature AM (AM-m), an active form, glycine-extended AM (AM-Gly), an inactive form, and total AM (AM-T: AM-m+AM-Gly) were measured by specific immunoradiometric assay in the femoral vein, pulmonary artery and femoral artery of 29 consecutive patients after the Fontan procedure. The eleven patients who had history of Kawasaki disease and have normal coronary and hemodynamics served as control. RESULTS: Patients who underwent Fontan procedure had significantly higher venous concentrations of AM-T, AM-Gly, and AM-m than age-matched normal controls (AM-T, 12.0+/-3.3 vs. 9.6+/-2.0; AM-Gly, 10.4+/-3.0 vs. 8.5+/-1.6; AM-m, 1.6+/-0.7 vs. 1.0+/-0.6 pmol/l, each p<0.05). In patients with Fontan procedure, there were no differences in plasma AM-T, AM-Gly or AM-m levels between the femoral vein and pulmonary artery, however, there was a significant step-down in the AM-m levels, but not in plasma AM-T or AM-Gly levels, between the pulmonary artery and femoral artery (1.3+/-0.6 to 1.0+/-0.6, p<0.05). The venous concentrations of AM-m correlated negatively with systemic blood flow (cardiac output) (r=-0.46, p<0.05). CONCLUSIONS: Results suggest that in Fontan circulation plasma AM-m is increased in parallel with those of AM-T and AM-Gly and that AM-m is extracted in the lung. Extracted AM-m may be involved in the regulation of pulmonary arterial tonus, although further studies are necessary to elucidate the exact role of AM in Fontan circulation.  相似文献   
993.
994.
The expression of iron homeostasis-related genes during rice germination   总被引:1,自引:1,他引:0  
To characterize Fe homeostasis during the early stages of seed germination, a microarray analysis was performed. mRNAs extracted from fully mature seeds or seeds harvested 1–3 days after sowing were hybridized to a rice microarray containing approximately 22,000 cDNA oligo probes. Many Fe deficiency-inducible genes were strongly expressed throughout early seed germination. These results suggest that the demand for Fe is extremely high during germination. Under Fe-deficient conditions, rice produces and secretes a metal-cation chelator called deoxymugineic acid (DMA) to acquire Fe from the soil. In addition, DMA and its intermediate nicotianamine (NA) are thought to be involved in long distance Fe transport in rice. Using promoter-β-glucuronidase (GUS) analysis, we investigated the expression patterns during seed germination of the Fe deficiency-inducible genes OsNAS1, OsNAS2, OsNAS3, OsNAAT1, and OsDMAS1, which encode enzymes that participate in the biosynthesis of DMA, and the transporter genes OsYSL2 and OsIRT1, which are involved in Fe transport. All of these genes were expressed in germinating seeds prior to protrusion of the radicle. These results suggest that DMA and NA are produced and involved in Fe transport during germination. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
995.
Progesterone is a mammalian gonadal hormone. In the current study, we identified and quantified progesterone in a range of higher plants by using GC-MS and examined its effects on the vegetative growth of plants. The growth of Arabidopsis (Arabidopsis thaliana) seedlings was promoted by progesterone at low concentrations but suppressed at higher concentrations under both light and dark growth conditions. The growth of the gibberellin-deficient mutant lh of pea (Pisum sativum) was also promoted by progesterone. An earlier study demonstrated that progesterone binds to MEMBRANE STEROID BINDING PROTEIN 1 (MSBP1) of Arabidopsis. In this work, we cloned the homologous genes of Arabidopsis, MSBP2 and STEROID BINDING PROTEIN (SBP), as well as of rice (Oryza sativa), OsMSBP1, OsMSBP2 and OsSBP and examined their expression in plant tissues. All of these genes, except OsMSBP1, were expressed abundantly in plant tissues. The roles of progesterone in plant growth were also discussed.  相似文献   
996.
997.
We examined the adolescent development of the sexual skin of chimpanzees (Pan troglodytes) by daily observation, evaluation of swelling, and weekly photogrametry. Although the size of swelling differed with the individual, the development of sexual swelling followed four stages: (1) initial stage, the labial region began to show a slight swelling and recovery; (2) labial stage, swelling at the labial region became maximal; (3) anal stage, another swelling center appeared in the anal region and enlarged; and (4) full maturity stage, the labial and anal regions merged into a full swelling. Menarche occurred after the beginning of the anal stage, and the regular cycle was then established. All of the swelling stages and the peak swelling size are regarded as good indicators of reproductive maturation in chimpanzees.  相似文献   
998.
999.
1000.
Mori Y 《Uirusu》2007,57(2):151-158
Herpesvirus entry into host cells occurs by recognition of specific cellular receptor(s) with viral envelope glycoproteins. Nucleocapsids formed in nucleus are released into cytoplasm, and acquire tegument proteins there. Nucleocapsids with tegument proteins bud into intracellular vesicles formed in infected cells, which are thought to be derived from Golgi apparatus, trans-Golgi network or endosomes. However, the precise mechanisms involved in virus final envelopment are poorly understood. Here, I review our current knowledge regarding herpesvirus entry into host cells and virus assembly.  相似文献   
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