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31.
Adrenomedullin (AM) was originally characterized in extracts of an adrenal medullary tumor. Since this original finding the peptide and its mRNA have also been found in the adrenal cortex, specifically, in the cells of the aldosterone-secreting zona glomerulosa. It is clear that the synthesis of AM is actively regulated in both cortex and medulla. Much research effort has been focused on identifying a role for AM in the adrenal gland. To date, no consistent effect on medullary catecholamine biosynthesis has been demonstrated. In the cortex the actions of AM are controversial and appear to depend on both the tissue preparation used and on the specific receptor population expressed in the individual gland. The results of further studies on the long-term actions of AM on adrenal growth and differentiation are awaited with interest. 相似文献
32.
Chaluntorn Vichasilp Kiyotaka Nakagawa Phumon Sookwong Ohki Higuchi Somchai Luemunkong Teruo Miyazawa 《LWT》2012,45(2):226-232
Mulberry 1-deoxynojirimycin (DNJ), a potent α-glucosidase inhibitor, suppresses postprandial blood glucose, thereby possibly preventing diabetes mellitus. At present, mulberry dry teas are commercially supplied as functional foods in many countries, but these products may not provide an effective dose (6 mg DNJ/60 kg human wt) due to their low DNJ content (about 100 mg/100 g of dry wt). Therefore, development of tea with higher DNJ content is desirable. To do this, we investigated distribution of DNJ content and α-glucosidase inhibitory activity in 35 Thai mulberry varieties. DNJ content in young leaves varied among mulberry varieties from 30 to 170 mg/100 g of dry leaves. Varieties having highest DNJ content were Kam, Burirum 60 and Burirum 51. Leaf position affected DNJ content: shoots > young leaves > mature leaves. DNJ concentration and α-glucosidase inhibitory activity were highly correlated (r = 0.84), suggesting that α-glucosidase inhibitory activity of mulberry leaves is mainly due to DNJ. Consequently, high DNJ content mulberry tea was produced from shoots of varieties such as Burirum 60, which contains 300 mg/100 g of dry wt. Tea-making conditions were optimized for highest DNJ extraction using response surface methodology. Approximate 95% of total DNJ in high DNJ content dry tea was extracted when temperature was maintained at 98 °C for 400 s; these conditions could be applicable for preparation of commercial products with high DNJ content. One cup (230 ml, a normal serving) of DNJ-enriched mulberry tea contained enough DNJ (6.5 mg) to effectively suppress postprandial blood glucose. 相似文献
33.
CdS/CuInSe2 (CIS) heterojunctions were investigated by XPS analysis. An In-excess layer which may form an ordered vacancy compound (OVC) was present at the as-deposited CIS surface and it remained after chemical bath deposition of a CdS layer. The In-excess layer was removed by preferential etching with NH3 aqueous solution. This result implies that the surface of the as-deposited CIS film was converted from the OVC with n-type conductivity into the CIS with p-type by NH3 treatment. The conduction band offsets at the CdS/p-CIS and CdS/n-OVC were determined to be 1.0 and 0.3 eV, respectively. The CIS solar cells fabricated with n-OVC surface layer exhibited higher cell efficiencies than those fabricated with p-CIS surface layer. 相似文献
34.
35.
Time-alternating method based on single-sideband holography with half-zone-plate processing for the enlargement of viewing zones 总被引:1,自引:0,他引:1
The single-sideband method of holography, as is well known, cuts off beams that come from conjugate images for holograms produced in the Fraunhofer region and from objects with no phase components. The single-sideband method with half-zone-plate processing is also effective in the Fresnel region for beams from an object that has phase components. However, this method restricts the viewing zone to a narrow range. We propose a method to improve this restriction by time-alternating switching of hologram patterns and a spatial filter set on the focal plane of a reconstruction lens. 相似文献
36.
37.
To obtain information on the change in fine structure of nylon 6 taking place during practical false-twisting processes, the manner of change in the three elemental processes, i.e., twisting, annealing, and untwisting, was studied. For simplicity, nylon 6 gut yarn was used instead of multifilament yarn. Wide- and small-angle x-ray diffraction (WAXD and SAXD) together with electron microscopy (EM) were used here. The degree of molecular orientation in the crystalline region of the twisted yarn gradually decreases with increase of the twist number (TN) in the region of TN ? 100. The long spacing, determined by SAXD, of the twisted yarn increases with increases in TN. The increase in long spacing cannot be interpreted only by macroscopic strain or elongation of the yarn in the twisting process. This difference seems to arise from the contribution of the decrease of lateral size of lamellae to the average long spacing; therefore the increase in long spacing should be attributed to the elongation of the amorphous region, deduced from the crystallinity measured by WAXD and the long spacing diffraction. The angle between the streak line on the surface of twisted yarn observed by EM and the fiber axis agrees well with the twist angle of the yarn. The crystal lamellae are stacked normal to the streak line at the initial stage, i.e., at a low value of TN, but they begin to deviate from the normal direction with increase in TN, accompanied by their partial destruction. Based on SAXD and density measurements, the internal strain of yarn annealed after twisting is fully relaxed. When the yarn is untwisted after twisting and annealing, the crystal orientation recovers gradually to that of the untreated yarn. The chain axis within the lamellae in the center region of the yarn becomes nearly parallel to the fiber axis, but the chain axis in the outer region does not. 相似文献
38.
39.
Kakimoto Y Naetoko Y Hara H Miyatake M Sato A Tatsuguchi H Takahata R Yamamoto R Joh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(3):165-174
A collaborative study involving 8 laboratories was conducted to evaluate a method for the simultaneous determination of pesticide residues in 6 types of fruits and vegetables (spinach, tomato, apple, radish, cabbage and carrot). The method of analysis was the same as reported by Kakimoto et al. in 2003. One hundred and thirty-nine pesticides were spiked by each of 8 laboratories at levels of 0.1 microg/g (pesticides analyzed by GC/MS) or 0.5 microg/g (pesticides analyzed by HPLC) into the 6 kinds of samples. Statistical analysis showed that 111 pesticides could be analyzed with practical precision by this method. For screening purposes, the method could analyze 118 pesticides. The median values of the limits of detection were 0.001-0.041 microg/g. The calibration curves were linear in the range of 0.5-5 microg/mL for most pesticides with median correlation coefficients of 0.983-1.000. 相似文献
40.
In the copolymerization of phenylacetylene with various acetylenes catalysed by WCl6·Ph4Sn, the relative reactivity of monomer decreased with increasing steric effect of monomer, e.g. HC Cn-Bu, HC Cn-Hex > HC CPh, HC Cs-Bu > HC Ct-Bu, MeCCPh, CICCPh. While 1-chloro-2-phenylacetylene (a disubstituted acetylene) showed high reactivity in the homopolymerization by Mobased catalysts, the reactivity was remarkably depressed in the presence of phenylacetylene as comonomer. Based on these results, the relative reactivity of the acetylenic monomers in copolymerization was explained in terms of competitive coordination of monomers to the propagating end. 相似文献