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The present study investigated characteristics of 24 parasite infection cases detected during colonoscopy in a regional hospital from January 2001 to December 2008. Sixteen patients were confirmed with Trichuris trichiura infection, 6 patients were with Ascaris lumbricoides infection, 1 patient with Enterobius vermicularis infection, and 1 patient with Anisakis infection. Among them, 7 patients (43.8%) were asymptomatic. Colonoscopy findings were normal in 18 patients (75.0%). Among the patients with T. trichiura infection, colonoscopy showed several erosions in 2 patients (8.3%) and non-specific inflammation of the affected segment of the colon in 3 patients (12.5%). In 1 patient with anisakiasis, colonoscopy revealed a markedly swollen colonic wall. Stool examinations were performed before treatment in 7 patients (29.2%) and were all negative for parasite eggs or worms. These results suggest that colonoscopy is a useful diagnostic approach for parasitic infections even for asymptomatic patients and for patients with negative stool examinations.  相似文献   
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A metagenomic fosmid library was constructed using genomic DNA isolated from abalone intestine. Screening of a library of 3,840 clones revealed a 36 kb insert of a cellulase positive clone (pAMHElO). A shotgun clone library was constructed using the positive clone (pAMHElO) and further screening of 3,840 shotgun clones with an approximately 5 kb insert size using a Congo red overlay revealed only one cellulase positive clone (pAMHL9). The pAMHL9 consisted of a 5,293-bp DNA sequence and three open reading frames (ORFs). Among the three ORFs, cellulase activity was only shown in the recombinant protein (CelAMll) coded by ORF3, which showed 100% identity with outer membrane protein A from Vibrio alginolyticus 12G01, but no significant sequence homology to known cellulases. The expressed protein (CelAMll) has a molecular weight of approximately 37 kDa and the highest CMC hydrolysis activity was observed at pH 7.0 and 37°C. The carboxymethyl cellulase activity was determined by zymogram active staining and different degraded product profiles for CelAMll were obtained when cellotetraose and cellopentaose were used as the substrates, while no substrate hydrolysis was observed on oligosaccharides such as cellobiose and cellotriose.  相似文献   
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Facile synthetic methods of 2′,5′-dideoxy-, 2′,3′-dideoxy- and 3′-deoxy-1,N 6-ethenoadenosine nucleosides by either an enzymatic dideoxyribosyl transfer reaction or a simple chemical reaction were proposed. The synthetic products were isolated and purified by preparative HPLC and their structures were confirmed by1H NMR (500 MHz) and FAB-MS including high resolution mass measurement. These modified nucleoside analogs have not been reported yet. Therefore, these modified nucleoside analogs are of potential value to be studied further for biological activity such as anticancer or antiviral.  相似文献   
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The transformed root culture of Polygonum tinctorium Lour. was established by infecting leaf explants with Agrobacterium rhizogenes A4. These cultures were examined for their growth and indigo content under various culture conditions. Among the four different culture media tested, SH medium showed the highest yield for root growth (28 mg dry wt/30 ml) and indigo production (152 g/dry wt). In SH medium, 30 g sucrose l–1, 2500 mg KNO3 l–1, 300 mg NH4H2PO4 l–1 were the best conditions for indigo production at pH 5.7. The production of indigo in hairy roots slightly increased with the addition of 200 mg chitosan l–1 (186 g/dry wt) and 20 U pectinase l–1 (181 g/dry wt).  相似文献   
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The role of the protein kinase Akt in cell migration is incompletely understood. Here we show that sphingosine-1-phosphate (S1P)-induced endothelial cell migration requires the Akt-mediated phosphorylation of the G protein-coupled receptor (GPCR) EDG-1. Activated Akt binds to EDG-1 and phosphorylates the third intracellular loop at the T(236) residue. Transactivation of EDG-1 by Akt is not required for G(i)-dependent signaling but is indispensable for Rac activation, cortical actin assembly, and chemotaxis. Indeed, T236AEDG-1 mutant sequestered Akt and acted as a dominant-negative GPCR to inhibit S1P-induced Rac activation, chemotaxis, and angiogenesis. Transactivation of GPCRs by Akt may constitute a specificity switch to integrate rapid G protein-dependent signals into long-term cellular phenomena such as cell migration.  相似文献   
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H+-Transport activity of the vesicles prepared from barley rootswas studied at the early phase after application of NaCl stress.The activity reached maximal level at 3 days after the treatmentwith 200 mM NaCl which moderately reduced the growth. This activityincrease could be suppressed in the presence of cycloheximideand actinomycin D. The properties of the membrane vesicles associated with H+-transportactivity prepared from both control and NaCl-stressed rootssuggested that it was of tonoplast origin based on the followingfindings: optimal pH at 7.5, strong inhibition by nitrate butnot by vanadate, and stimulation by chloride. The density gradient centrifugation of vesicles with DextranT70 did not show any detectable difference in the distributionpatterns of H+-transport activities between control and NaClstressedroots. Furthermore, Km values for ATP of the H+-transport activityof vesicles prepared from control and NaCl-stressed roots werethe same. Therefore, H+-transport activity with properties similarto those of the control roots was increased by NaCl stress.The results are discussed in terms of an adaptive mechanismof barley against salt stress. 1Permanent address: Department of Horticulture, College of Agriculture,Chonnam National University, Chonnam 500, Korea. (Received April 18, 1988; Accepted July 20, 1988)  相似文献   
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The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, TIM-1, is considered as a membrane protein that is associated with the development of Th2 biased immune responses and may be selectively expressed on Th2 cells. In the present study, we analyzed the association of allele and genotype frequencies between asthma or atopy patients and the controls without asthma and atopy using large sample size at 5383_5397del and 5509_5511delCAA variations of Tim-1 gene. Although the allele frequency of 5509_5511delCAA variation in asthma was not significantly different (P=0.085), the genotype of 5509_5511delCAA variation in asthma was significantly associated with the susceptibility to asthma (P=0.037). The genotype and allele frequencies of 5383_5397del variation in atopic dermatitis were significantly different from those in the non-asthmatic and non-atopic controls (P=0.005 and P=0.002, respectively). Our results strongly suggest that the 5383_5397del variation site of Tim-1 exon 4 might be associated with atopic dermatitis susceptibility.  相似文献   
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