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21.
We developed an enrichment medium for use with the loop-mediated isothermal amplification (LAMP) assay (enrichment media + LAMP assay) to quickly increase a very small number of Vibrio parahaemolyticus cells to the detection limit of the assay. Thirty-nine different enrichment media were prepared based on evaluating 12 potential ingredients. From our assessment of the 39 media, enrichment medium #36, which contained 2% sodium chloride, 1% proteose peptone no. 2, 0.1% trehalose, 0.5% α-ketoglutaric acid, 0.25% pyruvic acid, and 0.5% yeast extract (pH 8.6), was found to be most effective at enhancing the proliferation of V. parahaemolyticus during incubation for 3 h at 40oC. We compared the detection limits of the LAMP assay, the enrichment medium #36 + LAMP assay, and the cultivation method using bacterial cell and spiked shrimp sample tests. The detection limits of the LAMP assay, the medium #36 + LAMP assay, and the cultivation method were 10(3), 10(0)-10(-1), and 10(-1) CFU ml(-1), respectively. Enrichment medium #36 promoted a 10(3)- to 10(4)-fold increase in the bacterial population, and the detection limit of the enrichment media + LAMP assay was the same as that of the cultivation method.  相似文献   
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The purpose of this study was to analyze passive motion of the para- and retropharyngeal space (PRS) during swallowing using dynamic magnetic resonance imaging (MRI). We conducted a preliminary study involving 30 healthy volunteers who underwent dynamic MRI. Consecutive MRI axial images were obtained by examining the plane parallel to the hard palate at the level of the anterior inferior corner of C2. Anterior displacement of the posterior pharyngeal wall (PPW) was measured as a motion index of pharyngeal contraction. The displacement and internal angle of the bilateral external and internal carotid arteries (ECA and ICA) and the bilateral centroids of the PRS area, as well as the increase in PRS area, were calculated at rest and at maximum pharyngeal contraction. In most participants, the bilateral ECA, ICA, and centroids were anterointernally displaced by pharyngeal contraction. The normalized ECA displacement (r = 0.64, r 2 = 0.41), normalized ICA displacement (r = 0.60, r 2 = 0.37), and normalized centroid displacement (r = 0.43, r 2 = 0.19) were more than moderately positively correlated with the normalized PPW displacement. The normalized PRS area increase (r = 0.35, r 2 = 0.12) was weakly positively correlated with the normalized PPW displacement. These results revealed that PRS area increased as the ECA and ICA were drawn anterointernally via its passive motion by pharyngeal contraction.  相似文献   
24.
Microcystins, which are cyclic heptapeptides produced by some cyanobacterial species from algal blooms, strongly inhibit serine/threonine protein phosphatase and are known as hepatotoxins. Microcystins have many structural variations, yet insufficient information is available on the differences in the cytotoxic potentials among the structural variants. In this study, the cytotoxicities of 16 microcystin variants at concentrations of 0.03–10 μg/mL to primary cultured rat hepatocytes were determined by measuring cellular ATP content, and subsequently determined by their 50% inhibitory concentration (IC50). Differences in the amino acid constituents were associated with differences in cytotoxic potential. [d-Asp3, Z-Dhb7] microcystin-LR exhibited the strongest cytotoxicity at IC50 of 0.053 μg/mL among the microcystin variants tested. Furthermore, [d-Asp3, Z-Dhb7] microcystin-HtyR was also highly cytotoxic. These results suggest that both d-Asp and Z-Dhb residues are important in determining the cytotoxic potential of microcystin variants.  相似文献   
25.
Myxopapillary ependymoma (MPE) is a rare variant of conventional ependymoma found predominantly in the sacrococcygeal region in young adults and characterized by its distinct epithelial and stromal components (WHO grade I designation). MPE with extensive osteolysis is extremely uncommon and only up to 40 cases have been documented. A case is presented here in which imprint smears of a sacral tumor in an 18‐year‐old man revealed complex papillary structures, small loose clusters, or cord‐like structures of bland tumor cells embedded in a myxoid or mucinous background. The tumor cells possessed uniformly round nuclei with a smooth nuclear outline, fine granular chromatin, and small nucleoli. Slender cytoplasmic fibrillary processes and occasional intracytoplasmic vacuoles were observed. A cytologic diagnosis of a MPE was suggested and histochemical and immunohistochemical studies were conducted on formalin‐fixed, paraffin‐embedded material. Immunohistochemically, the tumor cells showed diffuse and strong membranous and cytoplasmic staining for cytokeratin AE1/AE3, glial fibrillary protein, and S‐100 protein, but negative for epithelial membrane antigen, pan‐neuroendocrine markers (i.e., NSE, chromogranin A, synaptophysin), or brachyury. The proliferative index with MIB‐1 was around 10%. The diagnosis of osteolytic MPE was confirmed based on cytopathologic, histopathological, immunohistochemical results, radiologic findings, and the location of the tumor. We demonstrated here the cytopathological features of osteolytic MPE with emphasis on differential diagnostic considerations. Diagn. Cytopathol. 2014;42:778–783. © 2013 Wiley Periodicals, Inc.  相似文献   
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Aims/IntroductionGestational diabetes mellitus (GDM) is one of the most common complications of pregnancy and is associated with adverse pregnancy outcomes. This study aimed to explore the associations between glycated hemoglobin (HbA1c) levels at the early stage of pregnancy and the GDM risk among non‐diabetic women in a nationwide study in Japan. In addition, the relationship between GDM and adverse pregnancy outcomes was also analyzed.Materials and MethodsThis cohort study (n = 89,799) used data from the Japan Environment and Children’s Study. We stratified the participants into four groups according to HbA1c levels at an early stage of pregnancy. We investigated the association of HbA1c at an early stage of pregnancy with the risk of GDM, and of GDM with the risk of some representative adverse pregnancy outcomes, using the multiple logistic regression model with adjustment for potential confounders.ResultsThe adjusted odds ratio for GDM per 0.1 percentage point increase in HbA1c (%) was 1.20. The adjusted odds ratio for developing GDM was significantly increased in women from the HbA1c 5.0–5.4% category. GDM significantly increased the adjusted odds ratio for adverse pregnancy outcomes, such as hypertensive disorders of pregnancy, polyhydramnios and premature birth.ConclusionsHigh‐normal HbA1c levels at the early stage of pregnancy are significantly associated with GDM risk in women in Japan. GDM was significantly associated with adverse pregnancy outcomes.  相似文献   
28.
With increasing expectations for carbon neutrality, dry reforming is anticipated for direct conversion of methane and carbon dioxide: the main components of biogas. We have found that dry reforming of methane in an electric field using a Pt/CeO2 catalyst proceeds with sufficient rapidity even at a low temperature of about 473 K. The effect of the electric field (EF) on dry reforming was investigated using kinetic analysis, in situ DRIFTs, XPS, and DFT calculation. In situ DRIFTs and XPS measurements indicated that the amount of carbonate, which is an adsorbed species of CO2, increased with the application of EF. XPS measurements also confirmed the reduction of CeO2 by the reaction of surface oxygen and CH4. The reaction between CH4 molecules and surface oxygen was promoted at the interface between Pt and CeO2.

In the dry reforming of methane in an electric field, the reaction between CH4 molecules and surface oxygen was promoted at the interface between Pt and CeO2.  相似文献   
29.
Methods are described for the production of syngeneic mouse anti-IgE monoclonal antibodies (mAb). Hybridomas were prepared by using spleen cells from mice immunized with a conjugate of keyhole limpet hemocyanin with monoclonal IgE. Serum titers varied from approximately 40 to 1000 micrograms/ml. The anti-IgE mAb were isolated by affinity chromatography on columns containing immobilized monoclonal IgE. The mAb are specific for isotypic determinants of IgE and do not react with other immunoglobulin isotypes. One of the mAb, which has a high affinity for IgE (Ka = 4.7 X 10(8) M-1), should be useful for studies of regulation of IgE. The applicability of the mAb to quantitative assays for IgE was demonstrated.  相似文献   
30.
A case of polymorphous low-grade adenocarcinoma (PLGA) in the submandibular gland is reported. A 72 year old woman presented with a 5 year history of a gradually expanding tumor in the submandibular region. The surgical specimen revealed a relatively well demarcated tumor, 35 × 35 × 20 mm in size. Macroscopically, necrosis and hemorrhage were not seen in the solid tumor. Histologically, the tumor growth pattern was variable, composed of tubular, papillary, solid, trabecular and cribriform structures. Immunohistochemically, some tumor cells were positive for epithelial membrane antigen (EMA), S-100 protein, keratin, and carcino-embryonic antigen (CEA). Electron microscopically, prominent microvilli projected into the luminal spaces, and basal lamina and hemidesmosomes were seen in the tumor cells adjacent to the connective tissues. The submandibular gland is an extremely rare location for PLGA. To the authors' knowledge, this is the first case of its kind reported in the English literature.  相似文献   
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