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Probiotics and Antimicrobial Proteins - This study aimed to elucidate the targets and mechanisms of anti-staphylococcal effects from bioactive metabolites produced by lactic acid bacteria. We aimed...  相似文献   
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Objective: The purpose of this study was to examine the utility of SurePath‐liquid‐based cytology (LBC) compared to conventional cytological preparations (CCP) in the identification of endometrial carcinoma. Methods: During a 13‐month period, direct endometrial samples were collected from 120 patients using the Uterobrush. The material comprised 30 cases each of endometrial carcinoma, proliferative endometrium, secretory endometrium and atrophic endometrium. The following points were investigated:(i) the frequency of cell clumps in endometrial carcinoma; (ii) the area of cell nuclei; (iii) overlapping nuclei. Results: (i) Comparison of the frequency of cell clumps with irregular protrusion pattern and papillo‐tubular pattern showed no statistically significant difference in either type of cell clump between CCP and LBC. (ii) Comparison of the nuclear area of cells showed a sequential decrease from endometrial carcinoma to secretory endometrium, to proliferative endometrium and to atrophic endometrium, which was significant in CCP and LBC. (iii) Nuclear area was significantly lower with LBC compared with CCP in endometrial carcinoma, secretory endometrium and proliferative endometrium but not atrophic endometrium. (iv) Comparison of the degree of overlapping nuclei showed a sequential decrease from endometrial carcinoma to proliferative endometrium, to secretory endometrium and to atrophic endometrium, which was significant in both CCP and LBC. (v) Comparison of the degree of overlapping nuclei between CCP and LBC showed no significant difference for normal types of endometrium, but LBC had significantly higher values (P < 0.0001) in endometrial carcinoma than in CCP. Conclusions: The results of this study revealed that applying diagnostic criteria used in CCP to LBC was easy to achieve, because LBC had excellent cytoarchitectural preservation and cells were well presented. Although we have not examined all cytological features of malignancy and have not considered atypical hyperplasia, we believe that this method may be a useful tool in the diagnosis of endometrial cytology.  相似文献   
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Visual afferents to the cat fastigial nucleus (FN) have been studied with single unit recordings and horseradish peroxidase techniques. A total of 158 cells responding to electrical stimulation of the optic chiasm (OCh) were extracellularly recorded from the dorsocaudal part of the FN. They were classified into three groups: type-1 cells (48%) which showed early suppression and late facilitation; type-2 cells (38%) which showed early facilitation and late suppression; type-3 cells (14%) which exhibited long lasting suppression with no signs of facilitation. Eight of 32 cells tested showed the same response patterns to photic stimulation as to electrical stimulation of the OCh. None of the cells responding to electrical and photic stimulation, however, were found in the rostral and ventral parts of the FN. Furthermore, 29 cells which responded to electrical stimulation of the OCh were tested for responses to moving pattern stimulation. Seven (4 type-2 cells and 3 type-3 cells) of the 29 cells showed clear modulation, reflecting the velocity component of a horizontally moving pattern. However, none of 13 type-1 cells tested exhibited apparent modulation in relation to movement of the pattern. In order to trace the possible pathways mediating visual signals to this part of the FN, the horseradish peroxidase (HRP) method was used. Injection of HRP into the caudal FN resulted in the labelling of many cells, predominantly in the medial (M) and the descending (D) vestibular nuclei and in lobules VI and VII of the cerebellar vermis. A series of experiments further indicated the presence of possible pathways propagating visual signals to the caudal FN. The main routes are: 1) via the nucleus of the optic tract (NOT)--the dorsal part of the medullary reticular formation--the M and the D vestibular nuclei--to the FN, and 2) via the superior colliculus--the pontine nuclei--vermal lobules VI and VII--to the FN. The different physiological response patterns of FN cells may indicate that several types of visual signals involved with visually guided movements impinge upon the dorsocaudal FN.  相似文献   
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The specificity of the action of polymyxin B was studied using liposomes as a model membrane system. Liposomes prepared from total lipids of Gram-negative bacteria Escherichia coli, a mixture of purified E. coli phosphatidylethanolamine and cardiolipin and a mixture of phosphatidylethanolamine and phosphatidylglycerol, were extremely sensitive to polymyxin while those prepared from lipids of Gram-positive bacteria Streptococcus sanguis, lipids of sheep erythrocyte membranes, mixtures of egg lecithin and negatively charged amphiphatic molecules, were less sensitive to the action of the antibiotic. Chlolesterol was shown to suppress the polymyxin-induced response in liposomes.  相似文献   
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Expression of human leukotriene A4 hydrolase cDNA in Escherichia coli   总被引:2,自引:0,他引:2  
The cDNA clone encoding human leukotriene A4 hydrolase was inserted into a vector pUC9 and expressed in Escherichia coli as a fusion protein containing the first 10 amino acid residues derived from a vector. The leukotriene A4 hydrolase activity was recovered in the soluble fraction of the transformants. The purified enzyme showed kinetic properties similar to the native enzyme, including inactivation by the substrate and sulfhydryl-modifying reagents. The results demonstrate that a protein with an Mr of 70,000 was expressed in Escherichia coli with a full enzyme activity and structural fidelity. Acquisition of the expression system makes it feasible to elucidate the reaction mechanism of the enzyme.  相似文献   
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Winged bean Kunitz chymotrypsin inhibitor (WCI) is encoded by a multigene family and accumulation of its mRNA is restricted in mid-maturation stage seeds and tuberous roots. In this paper, we analyzed the accumulation of mRNA derived from each WCI gene using a novel method: sequence-specific termination analysis. The results demonstrated that the accumulation of each WCI mRNA was differentially regulated in winged bean plants.  相似文献   
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