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1.
刘斌 《中国神经再生研究》2009,13(34)
利用电化学方法研究医用钛合金在0.9%NaCl生理盐水,模拟人工唾液,模拟人工体液中的腐蚀情况,分析腐蚀电位和腐蚀电流密度,扫面电镜观察腐蚀表面形貌,CA-A型接触角测试仪测试钛合金表面被腐蚀后接触角的变化。实验表明:钛合金在三种生理电解液中的腐蚀情况依次是:模拟人工唾液〉模拟人工体液〉0.9%NaCl生理盐水。扫面电镜观察表明,医用钛合金在0.9% NaCl生理盐水腐蚀后,表面出现了许多腐蚀孔,经模拟人体体液腐蚀后,表面变得粗糙不平整,腐蚀孔数目变化不大,钛合金经人工唾液腐蚀后,腐蚀孔数目增多,部分腐蚀孔孔径明显增大。经三种生理电解液腐蚀后,钛合金表面接触角都减小。结论:医用钛合金在人工唾液中的腐蚀最严重,在临床应用中应给予相应的防范措施。 相似文献
2.
HELENA MARKKANEN STINA M. SYRJÄNEN PEKKA ALAKUIJALA 《European journal of oral sciences》1986,94(2):115-120
Abstract — The concentrations of IgA, lysozyme and β-microglobulin (β2 -m) were quantitated in wax-stimulated mixed saliva from 28 patients with severe periodontitis and from 28 healthy controls. The mutual correlations between IgA, lysozyme and β2 -rn were determined. In patients with periodontitis decreased lysozyme concentrations were detected when compared with controls (P<0.05). The correlation between IgA and β2 -m concentrations was highly significant in both groups studied (P<0.0001, and P <0.002), whereas β2 -m and lysozyme concentrations were positively correlated in patients but not in controls. In addition, a significant correlation between IgA and lysozyme was found only in periodontal patients ( P <0.001). 相似文献
3.
Sucrose-dependent accumulation of oral streptococci and their adhesion-defective mutants on saliva-coated hydroxyapatite 总被引:1,自引:0,他引:1
The adhesion and accumulation of oral streptococci on saliva-coated hydroxyapatite was examined in strains representing species that appear in initial plaque ( Streptococcus sanguise FC1 and Streptococcus oralis C5) and in more mature plaque ( Streptococcus gordonii G9B). Washed cells of strains FC1 and C5 did not attach better to saliva-coated hydroxyapatite than did strain G9B, suggesting that the degree of initial adhesiveness does not alone account for the temporal appearance of these bacteria in dental plaque. Growing cells of each strain were also examined for their ability to accumulate on saliva-coated hydroxyapatite. The addition of sucrose to the medium promoted the accumulation of strain G9B more than it promoted the accumulation of strains FC1 and C5. Sucrose also enhanced the accumulation of adhesion-defective mutants of each strain to levels similar to those of the respective parent strains. These results suggest that sucrose-dependent accumulation may facilitate the colonization of the tooth surface by these species of oral streptococci when adhesion is limited by reduced bacterial adhesiveness or limited pellicle-binding sites. 相似文献
4.
The effect of prolonged treatment with amitriptyline on the secretory activity of rat salivary glands evoked by parasympathetic nerve stimulation and isoprenaline administration has been studied. Low doses of amitriptyline (10 mg/kg per day for 2 or 4 weeks), did not significantly affect salivary flow evoked by either parasympathetic nerve or isoprenaline stimulation. Higher doses of amitriptyline (50 mg/kg/day for 2 or 4 weeks) however, markedly decreased parasympathetic-evoked salivary secretion (flow and volume) from both parotid and submandibular glands, while isoprenaline-evoked secretions were unaffected. Sodium, potassium, and calcium concentrations of nerve-elicited or isoprenaline-evoked saliva were not significantly altered by amitriptyline treatment. Protein concentration and amylase activity of nerve-elicited parotid saliva were, however, greatly increased by chronic amitriptyline administration. Possible mechanisms for drug-induced increase in nerveelicited salivary protein concentration include changes in cholinergic receptor binding, release of neuropeptides and variations in phosphatidylinositol turnover, which need further study. 相似文献
5.
William G. Kohn Jonathan A. Ship Jane C. Atkinson Lauren L. Patton Philip C. Fox 《Journal of oral pathology & medicine》1992,21(2):70-74
Sequential salivary gland scintigraphy with 99mTc-technetium pertechnetate (Tc-99) is a safe, minimally invasive test for study of major salivary glands. However, its relationship to salivary function has not been investigated in detail. We have investigated the relationship between major salivary gland flow rates and Tc-99 scans and developed a new rating scale using scans of a control group with normal salivary function. Salivary flow rates and Tc-99 scans were obtained from healthy, non-medicated subjects (n = 33) and from xerostomic patients (n = 22). There were significant differences between the groups for salivary flow rates and Tc-99 ratings. Significant correlations were found between salivary flow rates and Tc-99 ratings in the control and xerostomic groups. The Tc-99 rating scale proved reliable in assessing salivary dysfunction, and showed a high inter-examiner correlation. These results demonstrate the usefulness of salivary gland scintigraphy in assessing major salivary gland flow rates and the utility of a new rating scale. 相似文献
6.
Arne Popma Robert Vermeiren Charlotte A M L Geluk Thomas Rinne Wim van den Brink Dirk L Knol Lucres M C Jansen Herman van Engeland Theo A H Doreleijers 《Neuropsychopharmacology》2007,61(3):405-411
BACKGROUND: In animals, strong evidence exists for an association between testosterone and aggression. In humans, and particularly in children and adolescents, findings have been less consistent. Previous research has suggested that this may partly be due to moderating effects of other factors, e.g., hormones. This study aims to investigate the moderating effect of cortisol on the relationship between testosterone and subtypes of aggression in delinquent male adolescents. METHODS: Participants were 103 boys (mean age 13.7) referred to a delinquency diversion program. Testosterone and cortisol levels were determined from saliva samples collected during resting conditions and related to self-report scores on overt and covert aggression. RESULTS: Linear regression analyses revealed a significant interaction between cortisol and testosterone in relation to overt aggression, with a significant positive relationship between testosterone and overt aggression in subjects with low cortisol levels but not in subjects with high cortisol levels. Using the same model for covert aggression, no significant effects of testosterone, cortisol, or testosterone x cortisol interaction were found. CONCLUSIONS: These results indicate a moderating effect of cortisol on the relationship between testosterone and overt aggression in delinquent male adolescents. Implications and directions for future research are discussed. 相似文献
7.
8.
本文采用直接放射免疫测定法,固定条件,按标准程序测得30名正常成人全唾液及血浆中的醛固酮(Aldosterone,Aldo)浓度。均值唾液为6.6±1.9nmol/L,血浆为32.5±8.0nmol/L,两者呈平行关系(r=0.4,P<0.05,=11.29+0.79X),浓度比平均为20.2%。结果进一步证实唾液作为临床测定Aldo标本的有效性与实用性,有助于对一些全身及口腔疾病进行诊断及估计预后,并可据以评价皮质类固醇治疗效果及用药的合理性。 相似文献
9.
Fanasy P. Deming Ibtisam Al-Hashimi Nasser Haghighat William W. Hallmon David G. Kerns Celeste Abraham Francisco Rivera-Hidalgo 《Journal of oral pathology & medicine》2007,36(3):132-135
Background: Reduction in salivary secretion is the hallmark of Sjögren's syndrome (SS). Calmodulin (CaM) and calmodulin binding proteins (CaMBPs) play a key role in the secretory process of saliva. Recent studies have suggested that SS‐B, an autoantibody associated with SS, is a CaMBP. This finding suggests that CaMBP may contribute to the loss of saliva in SS. To better understand the role(s) of these proteins in SS, the purpose of this study was to compare salivary CaMBPs in Sjögren's patients and controls. Methods: Saliva samples were collected from 20 patients and 20 age‐, race‐, and gender‐matched controls. CaM overlay was used to identify CaMBPs in saliva of patients and controls. Results: Higher number of salivary CaMBPs was observed among patients than controls. Conclusions: The increased number of salivary CaMBPs in SS may suggest a potential role for these proteins in the pathogenesis of the disease. 相似文献
10.
The aim of the study was to compare salivary variables in a group of vegetarians with a group of omnivores. Twenty-nine vegetarians, 19 women and 10 men, mean age 35 yr, and 28 omnivores, 20 women and 8 men, mean age 35 yr, were compared in terms of salivary secretion rate, pH, buffer capacity, mutans streptococci and lactobacilli. The vegetarians had a significantly higher secretion rate, but there were no other significant differences regarding the salivary variables. The difference in secretion rate may have been caused by some lifestyle factor(s) differing between vegetarians and omnivores which probably mainly include nutrient(s), texture and roughness of the food. 相似文献