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901.
Dietary proteins and trypsin inhibitors are known to stimulate the secretion of the satiety hormone cholecystokinin (CCK). A potato extract (Potein) contains 60% carbohydrate and 20% protein including trypsin inhibitory proteins. In this study, we examined whether Potein suppresses food intake in rats and whether it directly stimulates CCK secretion in enteroendocrine cells. In fasted rats, food consumption was measured up to 6 h after the oral administration of Potein or soybean trypsin inhibitor (SBTI). CCK-releasing activities of Potein and SBTI were examined in the murine CCK-producing cell line STC-1. Potein inhibited the trypsin activity in vitro with a potency 20-fold lower than that of SBTI. Oral administration of Potein dose-dependently suppressed food intake for 1-6 h. Potein, but not the SBTI, dose-dependently induced CCK secretion in STC-1 cells. These results suggest that Potein suppresses food intake through the CCK secretion induced by direct stimulation on enteroendocrine cells and through inhibition of luminal trypsin.  相似文献   
902.
The volatile constituents of cold-pressed peel essential oils of redblush grapefruit (Citrus paradisi Macfadyen forma Redblush) and pummelo (Citrus grandis Osbeck) from the same locality in Kenya were determined by GC and GC-MS. A total of 67 and 52 compounds, amounting to 97.9 and 98.8% of the two oils, respectively, were identified. Monoterpene hydrocarbons constituted 93.3 and 97.5% in the oils, respectively, with limonene (91.1 and 94.8%), alpha-terpinene (1.3 and 1.8%), and alpha-pinene (0.5%) as the main compounds. Sesquiterpene hydrocarbons constituted 0.4% in each oil. The notable compounds were beta-caryophyllene, alpha-cubebene, and (E,E)-alpha-farnesene. Oxygenated compounds constituted 4.2 and 2.0% of the redblush grapefruit and pummelo oils, respectively, out of which carbonyl compounds (2.0 and 1.3%), alcohols (1.4 and 0.3%), and esters (0.7 and 0.4%) were the major groups. Heptyl acetate, octanal, decanal, citronellal, and (Z)-carvone were the main constituents (0.1-0.5%). Perillene, (E)-carveol, and perillyl acetate occurred in the redblush grapefruit but were absent from the pummelo oil. Nootkatone, alpha- and beta-sinensal, methyl-N-methylanthranilate, and (Z,E)-farnesol were prominent in both oils.  相似文献   
903.
Since Gruner's pioneer work in 19341), vermiculite has been attracting the attention of mineralogists and soil scientists with much interest, probably because of its unique behaviour on cation exchange and of a component common in most soils derived from various parent rocks. A number of papers thereafter dealt with the mineral, revealing its properties, diagenesis, and distribution in soils. However, as information has been accumulated on vermiculite, especially on clay vermiculite, it became evident that the difference between vermiculite and montmorillonite is due simply to the difference in layer charge and that the division is essentially an arbitrary one2). Walker suggested that the Mg plus glycerol test would be the only one which appeared to be universaIlY valid in the identification of vermiculite, and that although the K test was still of value as an aid in the differentiation, it could no longer be reo commended as of universal validity. In recent years, several workers4-12) indicated that interlayer materials, especially Al-hydroxyls, prevented vermiculite from contracting to 10 Å in the K test and prevented montmorillonite from expanding to 18 Å in the Mg-glycerol test. This suggests that in the light of new evidences the 14 Å mineral hitherto believed as vermiculite, chlorite, or montmorillonite by the classical test should be reexamined after removal of interlayer materials.  相似文献   
904.
It was recently reported that kokumi substances such as glutathione are perceived through the calcium-sensing receptor (CaSR). In addition, screening by the CaSR assay and sensory evaluation revealed that γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) was a potent kokumi peptide. In this study, the quantities of γ-Glu-Val-Gly in various commercial fish sauces originating from Vietnam (Nuoc Mum), Thailand (Nampra), China (Yu-lu), Korea, Japan (Shottsuru and Ikanago-shoyu), and Italy (Garum) were investigated using a LC/MS/MS method followed by derivatization with 6-aminoquinoyl-N-hydroxysuccinimidyl-carbamate (AQC). The analyses revealed γ-Glu-Val-Gly at concentrations ranging from 0.04 to 1.26 mg/dL, indicating that γ-Glu-Val-Gly is widely distributed among various commercial fish sauces.  相似文献   
905.
Qualitative and quantitative Polymerase Chain Reaction (PCR) systems aimed at the specific detection and quantification of common wheat DNA are described. Many countries have issued regulations to label foods that include genetically modified organisms (GMOs). PCR technology is widely recognized as a reliable and useful technique for the qualitative and quantitative detection of GMOs. Detection methods are needed to amplify a target GM gene, and the amplified results should be compared with those of the corresponding taxon-specific reference gene to obtain reliable results. This paper describes the development of a specific DNA sequence in the waxy-D1 gene for common wheat (Triticum aestivum L.) and the design of a specific primer pair and TaqMan probe on the waxy-D1 gene for PCR analysis. The primers amplified a product (Wx012) of 102 bp. It is indicated that the Wx012 DNA sequence is specific to common wheat, showing homogeneity in qualitative PCR results and very similar quantification accuracy along 19 distantly related common wheat varieties. In Southern blot and real-time PCR analyses, this sequence showed either a single or a low number of copy genes. In addition, by qualitative and quantitative PCR using wx012 primers and a wx012-T probe, the limits of detection of the common wheat genome were found to be about 15 copies, and the reproducibility was reliable. In consequence, the PCR system using wx012 primers and wx012-T probe is considered to be suitable for use as a common wheat-specific taxon-specific reference gene in DNA analyses, including GMO tests.  相似文献   
906.
The effect of the crude extract from Siraitia grosvenori Swingle (SG-ex) on the postprandial rise in blood glucose level was investigated. The increase in plasma glucose level in response to the oral administration of maltose was significantly suppressed in rats when SG-ex was given orally 3 min before the maltose administration. There was, however, no effect when glucose was administered instead, suggesting that the antihyperglycemic effect of SG-ex is elicited by inhibition of maltase in the small intestinal epithelium. In vitro, SG-ex inhibited rat small intestinal maltase. Similar effects were also observed both in vivo and in vitro when the concentrate of the sweet elements (triterpene glycosides) prepared from SG-ex was used. Furthermore, the main sweet element of SG-ex, mogroside V, and some minor elements such as mogroside IV, siamenoside I, and mogroside III also exhibited maltase inhibitory effect with IC50 values of 14, 12, 10, and 1.6 mM, respectively. These results suggest that SG-ex exerts anti-hyperglycemic effects in rats by inhibiting maltase activity and that these effects are at least partially exerted by its sweet elements, triterpene glycosides.  相似文献   
907.
Introduction

Concerning the A-type humic acid found in different kinds of soil the writers fractionated each of its components and measured its lightabsorbing power and compared the characteristics of those components.  相似文献   
908.
In human bladder cancer patients, ultrasonography is extensively used not only to identify tumor masses but also to evaluate tumor size, shape, echogenicity, location, and degree of tumor invasion into the bladder wall. The information revealed by ultrasonography delineates the tumor's biological features and facilitates prediction of prognosis. However, in veterinary medicine the feasibility of using ultrasonography for these purposes has not been fully investigated. In this retrospective study, we reviewed cases of dogs with histologically confirmed bladder mass lesions, including transitional cell carcinoma (n = 22) and polypoid cystitis (n = 5), to determine whether ultrasonography could reliably predict bladder wall involvement. By following patients with transitional cell carcinoma until death, we also determined whether ultrasonographic tumor size, shape, echogenicity, and mass location were related to prognosis. Wall involvement as revealed by ultrasound was significantly (P = 0.00005) associated with histological muscular layer involvement with a sensitivity of 93% (95% Confidence interval, 79–98%) and specificity of 92% (95% Confidence interval, 76–98%). Ultrasonographic wall involvement (P = 0.03, vs. noninvolvement), heterogeneous mass (P = 0.02, vs. homogeneous mass), and trigone location (P = 0.01, vs. other locations) characteristics were significantly associated with shorter survival times in transitional cell carcinoma cases. Findings indicated that ultrasonographic characteristics such as wall involvement, heterogeneous mass, and trigone location could be reliable prognostic indicators in canine transitional cell carcinoma.  相似文献   
909.
910.
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