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11.
ABSTRACT:   A cDNA ( PyARP4 ) containing an open reading frame for a protein of 573 amino acids was identified in the marine red alga Porphyra yezoensis . The conceptual PyARP4 protein exhibits significant similarity to actin-related protein (ARP) 4 in the terrestrial plant Arabidopsis . Comparison of the deduced amino acid sequence showed moderate sequence identity (30%) to a conventional actin in P. yezoensis , as seen in comparisons between ARP and conventional actins of other organisms. A putative bipartite nuclear localization signal and an actin motif were found within the PyARP4 amino acid sequence. In a phylogenetic analysis, the PyARP4 was found to cluster with the ARP4 of other organisms. The expression level of PyARP4 did not change significantly among four developmental stages of life cycle and was lower than that of a conventional actin. This cDNA therefore may serve as a useful internal standard in gene expression analyses of differentially expressed genes in P. yezoensis .  相似文献   
12.

Although fish roes (or the egg-laden ovary) are seafood products with high nutritional value and are considered abundant in vitamins including vitamin B12, nevertheless, the detailed properties of vitamin B12 have not been fully elucidated in fish roe products. Vitamin B12 content was determined using C18-reversed-phase high-performance liquid chromatography after purification of samples from immunoaffinity columns. Salmon egg-laden ovary products (sujiko), salmon roe products (ikura), dried mullet roe products (bottarga), and white sturgeon roe products (caviar) were found to contain substantial levels of vitamin B12 (more than approximately 15 µg/100 g wet weight). Interestingly, high levels of vitamin B12 per 100 g wet weight have been measured in pollack roe products (tarako) and flying fish roe products (tobiko). Liquid chromatography–electrospray-ionization/tandem mass spectrometry analysis revealed that vitamin B12 was the predominant corrinoid in the evaluated fish roe products examined, while no inactive corrinoid compounds were identified. These results suggest that commercially available fish roe products could be an important source of vitamin B12 for use as a dietary product for humans.

  相似文献   
13.
Cell numbers of known species of nitrate- and nitrite-reducing bacteria, Selenomonas ruminantium, Veillonella parvula and Wollinella succinogenes , in the rumen of goats (25–30 kg) were estimated by competitive polymerase chain reaction (PCR). The number of S. ruminantium was the largest of the three species examined, and tended to be greater in goats fed a high-concentrate diet (5.6 × 107 cells/mL rumen fluid) than in goats fed a high-roughage diet (1.3 × 107 cells/mL). The number of V. parvula tended to be greater when goats were fed a high-roughage diet (6.7 × 103/mL) than when fed a high-concentrate diet (3.2 × 103/mL). The number of W. succinogenes was below the detectable level (< 1.0 × 102/mL) when a high-concentrate diet was fed, but was significantly increased by feeding a high-roughage diet (1.6 × 103/mL). Addition of potassium nitrate (6 g/day) to the high-concentrate diet tended to increase V. parvula , and significantly increased W. succinogenes , indicating that these two bacteria can be increased by feeding a diet containing nitrate.  相似文献   
14.
In the present study, we identified several food-derived collagen peptides in human blood after oral ingestion of some gelatin hydrolysates. Healthy human volunteers ingested the gelatin hydrolysates (9.4-23 g) from porcine skin, chicken feet, and cartilage after 12 h of fasting. Negligible amounts of the peptide form of hydroxyproline (Hyp) were observed in human blood before the ingestion. After the oral ingestion, the peptide form of Hyp significantly increased and reached a maximum level (20-60 nmol/mL of plasma) after 1-2 h and then decreased to half of the maximum level at 4 h after the ingestion. Major constituents of food-derived collagen peptides in human serum and plasma were identified as Pro-Hyp. In addition, small but significant amounts of Ala-Hyp, Ala-Hyp-Gly, Pro-Hyp-Gly, Leu-Hyp, Ile-Hyp, and Phe-Hyp were contained.  相似文献   
15.
Insulin secretion by anomers of d-glucose   总被引:6,自引:0,他引:6  
A Niki  H Niki  I Miwa  J Okuda 《Science (New York, N.Y.)》1974,186(4159):150-151
Isolated rat islets were incubated for 5 minutes in the media containing either the alpha or beta anomer of D-glucose (2 milligrams per milliliter). The amounts of secreted insulin and changes of anomers ratio were concomitantly determined. In spite of rapid mutarotation, significantly greater stimulation of insulin secretion was observed by alpha-D-glucose as compared with beta-D-glucose.  相似文献   
16.
评价大米储藏品质的炊饭特性指标的研究   总被引:1,自引:0,他引:1  
提出了评价大米储藏品质的炊饭特性新指标——光透过率差。实验证明,随着大米品质的劣化,光透过率差明显变小。以此指标为主,结合原有的加热吸水率和pH值,对因生霉和陈化引起的大米储藏品质的变化,都能较好地进行评价。同时对影响这些指标稳定的实验因素也进行了探讨。  相似文献   
17.
Procyanidin fractions from apple were separated according to the degree of polymerization using normal phase chromatography. Evaluation of physiological functionalities of procyanidins requires individual structural determination. However, it is difficult to elucidate the structure of procyanidins, in particular those with (+)-epicatechin (1) or (-)-catechin (2) units, and determine whether the interflavanoid bonds are 4beta-->8 or 4beta-->6 without cleavage and acetylation. Structural determination used LC-MS and low-temperature NMR. Nine procyanidins were separated by preparative HPLC consisting of three well-known procyanidins [procyanidin B1 (3), procyanidin B2 (4), and procyanidin C1 (5)] and six new procyanidins [epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-catechin (6); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-catechin (7); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-epicatechin (8); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-catechin (9); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-epicatechin (10); and epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin (11)]. Compounds 6-11 were detected for the first time as apple constituents.  相似文献   
18.
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively.  相似文献   
19.
20.
OBJECTIVE: To compare activities of interleukin (IL)-1beta, IL-6, tumor necrosis factor (TNF)-alpha, and matrix metalloproteinase (MMP)-3 and contents of sulfated glycosaminoglycan (S-GAG) in joint fluid obtained from dogs with hip dysplasia (HD) and clinically normal dogs, evaluate correlations among these markers in joint fluid obtained from dogs with HD, and evaluate correlations between each marker and clinical and radiographic variables. Animals-26 dogs with HD (clinical group) and 43 clinically normal Beagles (control group). PROCEDURE: Joint fluid was aseptically collected from the hip joints of all dogs. For each dog in the clinical group, age, duration of lameness, radiographic osteoarthritis (OA) score, and Norberg angle in each affected joint were recorded. Activities of IL-1beta, IL-6, TNF-alpha, and MMP-3 and S-GAG contents were measured. Values were compared between groups by use of Mann-Whitney U tests, and the Spearman rank correlation test was used to evaluate correlations among markers and between each marker and clinical or radiographic variables. RESULTS: Values of all markers were significantly higher for the clinical group, compared with values for the control group. There was a moderate positive correlation between lameness duration and IL-6 activity and a strong negative correlation between the Norberg angle and IL-1beta activity. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of our results indicated that there was a significant increase in markers of OA in dogs with HD. Activities of IL-1beta and IL-6 in joint fluid of dogs with HD may be influenced by the severity of laxity in the hip joint and lameness duration, respectively.  相似文献   
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