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131.
Nd:YAG激光对牙本质钙/磷比值的影响 总被引:1,自引:0,他引:1
朱庆萍 《临床口腔医学杂志》1998,14(3):131-132
为探讨Nd:YAG激光对牙本质矿物含量的影响,应用扫描电镜和能谱仪定点测量50个上前牙标本的根管壁(激光照射工和正常对比区)的钙、磷含量,结果表明,照射区牙本质钙/磷(Ca/P)比值高于对比区,当激光能量达15W以上时变化更为显著,提示Nd:YAG激光能提高牙本质的钙化程度。 相似文献
132.
R. DE BOER W. A. D. VAN DER HOEVEN S. O. STAPEL 《Clinical and experimental allergy》1995,25(8):765-770
Background: Fluctuations in the level of mite allergens in domestic house dust are the result of changes in the balance between synthesis, removal and decay. Purely physical forces as well as enzymatic degradation, mediated by house dust inhabiting microbes, may contribute to the decay of allergens in domestic dust. Knowledge about the speed of decay is essential for an understanding of the dynamics of allergen levels. Objective: The present study is a quantitative assessment of the speed of decay at nine combinations of temperature (15°C, 20°C and 25°C) and relative humidity (33%, 55% and 75%). Methods: Samples of mite infested material of an old rug were stored at these temperature/relative humidity-combinations for 6, 12 or 18 months, after the mites were killed by cither a freezing treatment or an acaricide (lindane). The microbes living in the rug presumably survive these treatments. Concentrations of Der p I and Der p II + Der f II. in extracts of the rug material, were measured by a radio immunoassay. Results: No significant changes in the levels of Der p I and Der p II +Der f II, could be detected even after 11/2 year at a high temperature and humidity. Conclusion: These findings incidate that mite allergens can be extremely stable under normal domestic circumstances. 相似文献
133.
J. B. Payne R. A. Reinhardt M. P. Masada L. M. DuBois A. C. Allison 《Journal of periodontal research》1993,28(6):451-453
Gingival crevicular fluid (GCF) IL-8 and IL-1,1β levels were determined by sandwich enzyme-linked immunosorbent assays. Associations between IL-8 and IL-1β GCF levels, and between these cytokines and patient estrogen status were evaluated. IL-8 and IL-1β were detected more frequently and in higher amounts/30 s GCF sample in estrogen-deficient patients than in estrogensufficient patients. IL-8 and IL-1β GCF levels were significantly correlated. These lindings suggest that GCF IL-8 levels are associated with patient estrogen status and local IL-1β concentrations. 相似文献
134.
Transcriptional downregulation of tight junction protein ZO-1 in active coeliac disease is reversed after a gluten-free diet 总被引:1,自引:0,他引:1
135.
Introduction. – L'objectif de cette étude est d'observer l'influence des paramètres anthropométriques sur la performance en aviron, chez des rameurs de niveau national et international.Synthèse des faits. – Les mesures anthropométriques ont été réalisées sur 88 rameurs (dont 11 évoluant au niveau international) lors des championnats de France de 2002. Ces mesures ont été corrélées aux performances réalisées sur ergomètre et en bateau. Des différences significatives sont mises en évidence entre les caractéristiques anthropométriques des rameurs de niveau national et international. Ces caractéristiques semblent être reliées directement aux performances ergométriques et non à celles réalisées en bateau.Conclusion. – L'influence des caractéristiques anthropométriques sur la performance en aviron pourrait être modifiée en fonction des niveaux de compétition.Aim. – Observe the influence of anthropometrics characteristics on rowing performance, at national and international level.Results. – Anthropometrics measurements of 88 rowers (included 11 international rowers) were realized during the national championships, data were correlated to ergometer and boat performances. Significant differences appear between anthropometrics characteristics of national and international rowers. Anthropometrics parameters seem related to ergometer performance but not to boat performances.Conclusion. – The influence of anthropometrics characteristics on rowing performance could be modified by the competitive level. 相似文献
136.
5种真空采血促凝管在生化检验中的应用及评价 总被引:4,自引:0,他引:4
目的 评价五种真空采血促凝管对常规生化检测项目的影响。方法 采集健康体检者及自愿者血液标本100例,选用5个不同厂家生产的真空采血促凝管,与美国BD公司生产的无添加剂的血清管进行采血质量和生化检测对比评价。结果 5个厂家生产的真空采血促凝管与BD公司生产的无添加剂血清管在多数生化检验项目上无明显差异(P>O.05),但有3个国内厂家生产的真空采血促凝管在标本采集质量、分离效果上存在明显不足,且在血清K、LDH、HBD、CK、CHOL、TG、HDL-c、LDL-c、APOA、APOB等检测上与对照组间存在着显著差异(P<0.05且r相似文献
137.
138.
The usefulness of intra-operative antiemetics and postoperative oral fluid restriction in the prevention of vomiting following anaesthesia for ophthalmic surgery, was studied in 200 patients. They were allocated into four groups of 50 and given either saline (as control), droperidol, metoclopramide or prochlorperazine. Oral intake was restricted postoperatively in half of the patients of each group. Anaesthesia comprised morphine and atropine premedication and a halothane, nitrous oxide and oxygen spontaneous breathing technique. No significant beneficial effects resulted from intra-operative antiemetics; vomiting incidences of 26% after saline and droperidol, 28% after metoclopramide and 14% after prochlorperazine were observed. Younger patients and females vomited most frequently. Restriction of oral fluids did not decrease the incidence of vomiting but demonstrated that approximately half of those patients who vomit do so with their first postoperative oral intake. Vomiting was observed more frequently after non intra-ocular surgery than after intra-ocular surgery (37% cf. 16%, p less than 0.01) and postoperative analgesics were required by more non intra-ocular patients than by intra-ocular patients (25% cf. 5%, p less than 0.001). Squint patients vomited most frequently (48%) and most frequently required postoperative analgesia (35%). 相似文献
139.
The complex enterprise of modelling prenatal exposure to cigarettes: what is ‘enough’? 总被引:1,自引:0,他引:1
Kate E. Pickett Paul J. Rathouz Vanja Dukic Kristen Kasza Marina Niessner Rosalind J. Wright Lauren S. Wakschlag 《Paediatric and perinatal epidemiology》2009,23(2):160-170
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies. 相似文献
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies. 相似文献
140.