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101.
The present investigation aims at understanding the role of chemically modified starch on the firmness of fresh or stale bread. Bread was prepared from wheat flour or substituted wheat flour that contained 18% chemically modified tapioca starch and 2% vital gluten. Hydroxypropylated tapioca starch (HTS), acetylated tapioca starch (ATS), phosphorylated cross‐linked tapioca starch (PTS), and native tapioca starch (NTS) were tested. Bread prepared from the substituted flour with PTS showed a firmer texture on the day of baking compared with bread prepared from NTS, HTS, and ATS. PTS retained its granular structure in the gluten network after baking and seemed to play the role of filler particles in the gluten matrix, thereby increasing firmness of fresh bread crumb. Bread prepared from the substituted flour with HTS or ATS firmed at a lower rate and showed a lower endothermic melting enthalpy of amylopectin after three days of storage compared with NTS or PTS. These findings suggest that the staling of bread containing chemically modified tapioca starch involves recrystallization of amylopectin.  相似文献   
102.
The interaction between fractalkine/CX(3)CL1 and its receptor CX(3)CR1 has been reported to play an important role in various human inflammatory diseases, including inflammatory bowel disease (IBD) mediated by lymphocyte chemoattraction. The objective of this study was to investigate the role of fractalkine and CX(3)CR1 in lymphocyte migration in canine IBD. IBD was diagnosed in 34 dogs, and 19 healthy beagles were used as normal controls. We quantified intestinal mRNA and protein expression of fractalkine and CX(3)CR1 by real-time RT-PCR and ELISA, respectively, and examined the localization of fractalkine in canine intestine by immunohistochemistry. The expression of CX(3)CR1 and surface antigens on peripheral blood mononuclear cells (PBMCs) and intraepithelial lymphocytes (IELs) was analyzed by flow cytometry. Intestinal fractalkine and CX(3)CR1 mRNA was significantly up-regulated in IBD dogs compared with the healthy control dogs. In addition, fractalkine expression on intestinal epithelial cells was significantly increased in the intestinal mucosa of IBD dogs compared with the healthy dogs. CX(3)CR1(+) PBMCs were significantly elevated in IBD dogs and positively correlated with the histopathological severity of IELs infiltration. These CX(3)CR1(+) PBMCs predominantly expressed markers for cytotoxic T cells. Almost all IELs expressed CD3, and the majority of cells expressed CD8 rather than CD4, which was analogous to the CX(3)CR1(+) PBMCs. These results suggest that the fractalkine-CX(3)CR1 interaction may contribute to the pathogenesis of canine IBD through migration of IELs.  相似文献   
103.
Thymus and activation-regulated chemokine (TARC) is known as a functional ligand for CC chemokine receptor 4 (CCR4), which is selectively expressed on Th2 lymphocytes and induces selective migration of the cells to allergic lesions. In this study, we cloned canine TARC cDNA from canine thymus by RT-PCR with rapid amplification of cDNA ends (RACE) method. The canine TARC clone contained a full-length open reading frame encoding 99 amino acids and included four cysteine residues characteristic to CC chemokine family. The canine TARC cDNA showed 77.5%, 67.4%, and 68.5% amino acid sequence similarity with human, mouse and rat homologues, respectively. Expression of TARC mRNA was detected not only in thymus but also in spleen, lymph node, lung and heart of the various normal dog tissues examined. TARC cDNA clone obtained in this study will be useful for further investigation on allergic diseases in dogs.  相似文献   
104.
Green tea, one of the most popular beverages consumed in Asian countries, has been reported to possess anticarcinogenic and antimutagenic properties. The aim in this study is to test the radical scavenging effect of catechins and caffeine, which were major components of green tea, and if they really prevent oxygen radical-induced mutagenesis. We used TA102 strain of Salmonella typhimurium which is sensitive to hydroxyl radical in the Ames mutation assay. We found that caffeine did not show any effects on mutagenesis in this system, but catechin significantly reduced mutagenesis or genotoxicity caused by hydroxyl radical. This radical-scavenging action of catechins may indeed contribute to the anticarcinogenic activity of green tea as has been proposed.  相似文献   
105.
Feeding systems such as grazing affect the fatty acid profile of bovine milk fat. In addition, milk fat is formed as the product of fatty acid metabolism in cow bodies before being secreted into milk. However, how grazing influences milk fatty acid profile through the metabolism has not been completely characterized. When fatty acid concentrations in Holstein milk were compared between grazing and non‐grazing periods, α‐linolenic acid was significantly higher in the grazing period than in the non‐grazing period. This could be explained with an increase in α‐linolenic acid feeding with grazing. α‐linolenic acid had a linear positive correlation with conjugated linoleic acid (9c,11t‐18:2) (CLA) and vaccenic acid (VA) during the grazing period, whereas CLA had higher correlation with linoleic acid rather than with α‐linolenic acid during the non‐grazing period. These data indicate that the high content of dietary α‐linolenic acid affects CLA and VA formation in milk of grazing periods via α‐linolenic acid metabolism into VA.  相似文献   
106.
Endoscopic polypectomy and argon plasma coagulation (APC) were performed in a refractory case of inflammatory colorectal polyps in a 7-year-old male Miniature Dachshund. Colonoscopic examination revealed a large sessile polyp and multiple diffuse small polyps, localized to the descending colon and rectum. The case showed a poor therapeutic response to prednisolone and cyclosporine. Under anesthesia, piecemeal resections were performed by polypectomy. APC was carried out to cauterize the polyp remnants. After treatment, reduction of the lesions and the improvement in clinical signs were observed, without recurrence of lesions for at least 10 months. Endoscopic treatment by polypectomy and APC is suggested to be a therapeutic option for refractory cases of inflammatory colorectal polyps in dogs.  相似文献   
107.
108.
A chitosan-degrading bacterium, isolated from field soil that had been amended with chitin, was identified as Sphingobacterium multivorum KST-009 on the basis of its bacteriological characteristics. The extracellular chitosanase (SM1) secreted by KST-009 was a 34-kDa protein and could be purified through ammonium sulfate precipitation, gel permeation column chromatography and SDS polyacrylamide gel electrophoresis. A chitosanase gene (csnSM1) was isolated from genomic DNA of the bacteria, and the entire nucleotide sequence of the gene and the partial N-terminal amino acid sequence of the purified SM1 were determined. The csnSM1 gene was found to encode 383 amino acids, 72 N-terminal amino acid residues were processed to produce the mature enzyme during the secretion process. Germinated microconidia of four formae speciales (lycopersici, radicis-lycopersici, melonis, and fragariae ) of Fusarium oxysporum were treated with SM1. Chitosanase treatment caused morphological changes, such as swelling of hyphal cells or indistinctness of hyphal cell tips and cessation or reduction of mycelial elongation. Received 2 May 2001/ Accepted in revised form 21 June 2001  相似文献   
109.
Occurrence of New Powdery Mildew on Greenhouse Tomato Cultivars   总被引:2,自引:0,他引:2  
During a year-round survey on the occurrence of powdery mildew on greenhouse-cultivated tomato plants, the disease was most severe in June and July. All tomato plants (45 commercial cultivars and 11 breeding lines) tested were infected with the pathogen but had different degrees of susceptibility. The pathogen was epiphytic and produced white, round pustules mainly on leaves of tomato plants. The pathogen produced conidia singly on conidiophores and forked appressoria on inoculated tomato leaves and seemed to be an Oidium sp. of Erysiphe polygoni type. Received 18 December 2000/ Accepted in revised form 22 July 2001  相似文献   
110.
Using melon seedlings at the cotyledon stage and genetically marked fungi, a system for monitoring pathogenic and nonpathogenic Fusarium oxysporum was devised in the present study. Protoplasts were prepared from three formae speciales (melonis, radicis-lycopersici and fragariae )of F. oxysporum and transformed with a synthetic gene for green fluorescence protein. Transformants were primarily isolated in the presence of hygromycin B and then screened by the emission of bright green fluorescence. Roots of melon seedlings were inoculated with fluorescing microconidia of these fungi, and fungal infection behavior was traced. Using fluorescence microscopy, we directly observed not only the fungus at the root surface, but also the mycelia elongating in the trachea of roots. Both pathogenic and nonpathogenic fungi germinated and hyphae elongated superficially on the surface of root. Only pathogenic fungi caused root necrosis at the inoculation site. Hyphae grew within the stem to induce constriction or cracking of lower hypocotyls, then causing wilting of the seedlings. Infection behavior of genetically marked pathogenic and nonpathogenic F. oxysporum could be successfully monitored after inoculation of cotyledons of seedlings. Received 6 June 2001/ Accepted in revised form 3 August 2001  相似文献   
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