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The relationship of gingival crevicular fluid short chain carboxylic acid concentration to gingival inflammation 总被引:2,自引:0,他引:2
R. Niederman Y. Buyle-Bodin B.-Y. Lu C. Naleway P. Robinson R. Kent 《Journal of clinical periodontology》1996,23(8):743-749
Abstract Short-chain carboxylic acids (SCCA; C≤5: e.g., lactic acid, propionic acid, butyric acid) are metabolic by-products of bacterial metabolism which accumulate in the gingival crevice, and exhibit significant biological activity, including the ability to alter gene expression. It has been hypothesized that among the activities of SCCAs are their ability to contribute to gingival inflammation. This concept complements the notion that specific periodontal pathogens are the causative agents of gingival inflammation. To begin testing these 2 hypotheses, we examined the relationship between SCCA concentrations, specific putative periodontal pathogens, and gingival inflammation in medically healthy periodontally diseased subjects. We reasoned that if SCCAs and/or specific periodontal pathogens were causative gingival inflammatory agents, gingival inflammation should increase with increasing concentration of the inflammatory mediator. We also recognized that other clinical variables needed to be controlled for, and an objective quantitative assessment of gingival inflammation used. To accomplish these tasks, sites within subjects were stratified by location and pocket depth, and the following quantified: bacteria] presence; SCCA concentration: and gingival inflammation. The results indicated that gingival inflammation directly and significantly correlated with SCCA concentrations in the maxillary and mandibular molars, incisors and canines (all r≥0.47; all p≤ 0.015; too few bicuspids were available for complete analysis). The relationship between gingival inflammation and SCCA concentration was best described by a natural log relationship. Gingival inflammation did not, however, correlate positively with either the total number of specific putative periodontal pathogens, or the sum of subsets of these pathogens (?0.31 ≤r≤ 0.39; 0.08 ≤p 0.75) for any of the locations. Finally, the SCCA concentration did not correlate with the level of individual or groups of pathogens. These data, together with historical work and other preliminary data, support the hypothesis that SCCA, rather than specific putative periodontal pathogens, may be a causative agent in gingival inflammation. This work may, in part, begin to explain the apparent lack of a direct relationship between current gingival inflammation and the prediction of bacterially mediated periodontal attachment loss. 相似文献
194.
本文研究和建立了超滤衍生化高效液相色谱法(HPLC)测定血浆中游离顺氨氯铂浓度的方法。取肝素抗凝的血浆样品用CAX-50超滤膜(截留物分子量>50000)超滤、去除血浆蛋白和与血浆蛋白结合的药物。在滤液中收集得到的游离顺氨氯铂以及与小分子物质结合的顺氨氯铂,通过柱前衍生化反应,生成的Pt(DDTC)_2在254nm波长处有较强的吸收,经过HPLC分离与检测。流动相为甲醇:水(4:1,v/v),固定相为YWG-C_18H_37(5μm)化学键合相,以NiCl_2为内标,顺氨氯铂和内标衍生物的保留时间分别为4.84和6.50min。在浓度为100.8~705.6ng/ml范围内呈良好线性,相关系数r=0.9995。 相似文献
195.
自1994年4月采用内窥镜已行额、面部除皱术22例,取得了较好的临床效果。介绍了应用内窥镜除皱术的操作方法、适应证选择的经验体会。认为在选择好适应证的前提下,是一种简洁的除皱方法。 相似文献
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You M. Lu Bu F. Lu Yu L. Yan Tin H. Yan Xiaon P. Ho Wen J. Wang 《The European journal of neuroscience》1993,5(10):1334-1338
The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsPs ) and inositol 1,4,5-trisphosphate (InsP3 ) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF− 4 -stimulated formation of [3 H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [3 H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage. 相似文献
199.
为了探讨城乡学龄前儿童视觉运动整合发育的特点,本文采用视觉运动整合发育测试(VMI)对597名城乡集体及散居学龄前儿童进行测查。结果显示:3岁段各组VMI得分比较无差异,而其它年龄段均显示散居儿童低于集体儿童(P相似文献
200.