排序方式: 共有7条查询结果,搜索用时 218 毫秒
1
1.
2.
Points out that after perusal of the Statistical Package for Social Sciences 5 (SPSS5), an omission was found in the Crosstabs section. Specifically, the chi-square statistic does not take into account that no more than 20% of the cells in any matrix should have an expected frequency of less than 5. After writing to SPSS, Inc., requesting an explanation for the omission and because the latest version (SPSS8) did not correct the omission, the author therefore warns potential and past users of this fact. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Andréa G. Antonio Renata S. Moraes Daniel Perrone Lucianne C. Maia Kátia Regina N. Santos Natália L.P. Iório Adriana Farah 《Food chemistry》2010
Coffee beverage has been associated with antibacterial activity against Streptococcus mutans, a cariogenic bacterium. This study aimed at identifying natural compounds in coffee that contribute to such activity and investigate the influence of species, roasting and decaffeination on it. Coffee chemical compounds and aqueous extracts of green and roasted regular and decaffeinated Coffea arabica and Coffea canephora beans were tested. MIC, biofilm inhibition and biofilm reduction results were correlated with the concentration of coffee compounds in the extracts. 5-Caffeoylquinic acid, trigonelline and caffeic acid solutions showed bacteriostatic activity (MIC = 0.8 mg/mL). Lighter and regular extracts showed higher inhibitory activity than darker and decaffeinated extracts, with an inverse correlation between bacterial colony-forming units and roasting degree. Only regular C. canephora extracts showed biofilm formation inhibition. The joint effect of chlorogenic acids, trigonelline and caffeine or other compounds removed by decaffeination seems to be one of the causes for coffee antibacterial activity against S. mutans. 相似文献
4.
In Situ analysis of CO2 laser irradiation on controlling progression of erosive lesions on dental enamel
下载免费PDF全文
![点击此处可从《Microscopy research and technique》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Taísa Penazzo Lepri Renata Siqueira Scatolin Vivian Colucci Adílis Kalina De Alexandria Lucianne Cople Maia Cecília Pedroso Turssi Silmara Aparecida Milori Corona 《Microscopy research and technique》2014,77(8):586-593
The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty‐six slabs of bovine incisors enamel (5 × 3 × 2.5 mm3) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH = 2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (λ = 10.6 µm; 0.5 W) and nonirradiate. After a 2‐day lead‐in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross‐over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three‐way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P = 0.419). Erosive challenge significantly increased enamel wear (P = 0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2‐laser irradiated and non‐irradiated (P = 0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid. Microsc. Res. Tech. 77:586–593, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
5.
J. A. Bouwstra N. Nahmoed H. W. W. Groenink M. Ponec 《International journal of cosmetic science》2012,34(6):560-566
In this study, the mode of action of moisturizers on the level of water in the stratum corneum was studied using cryo‐scanning electron microscopy. As model for dry skin, we used human skin equivalents (HSEs) generated at 93% or 60% relative humidity (RH). During the generation of the HSEs, the moisturizers were applied during a period of maximal 2 weeks. In HSEs generated under normal culture conditions (93% RH), application of 10% glycerol or 5% urea formulations resulted in increased water levels. Whereas the 5% urea formulations resulted mainly in the formation of intercellular water domains, after 10% glycerol both swelling of corneocytes and formation of intercellular water domains were noticed. A reduction in RH to 60% during treatment reduced the stratum corneum water levels drastically. Treatment with the non‐occlusive lipophilic moisturizer isopropyl isostearate resulted in increased water level in the central part of the stratum corneum compared with the untreated control. Our results show that HSEs can be used as a model to study the water distribution. 相似文献
6.
R van der Voort TE Taher RM Keehnen L Smit M Groenink ST Pals 《Canadian Metallurgical Quarterly》1997,185(12):2121-2131
T cell-dependent humoral immune responses are initiated by the activation of naive B cells in the T cell areas of the secondary lymphoid tissues. This primary B cell activation leads to migration of germinal center (GC) cell precursors into B cell follicles where they engage follicular dendritic cells (FDC) and T cells, and differentiate into memory B cells or plasma cells. Both B cell migration and interaction with FDC critically depend on integrin-mediated adhesion. To date, the physiological regulators of this adhesion were unkown. In the present report, we have identified the c-met-encoded receptor tyrosine kinase and its ligand, the growth and motility factor hepatocyte growth factor/scatter factor (HGF/SF), as a novel paracrine signaling pathway regulating B cell adhesion. We observed that c-Met is predominantly expressed on CD38(+)CD77(+) tonsillar B cells localized in the dark zone of the GC (centroblasts). On tonsil B cells, ligation of CD40 by CD40-ligand, induces a transient strong upregulation of expression of the c-Met tyrosine kinase. Stimulation of c-Met with HGF/SF leads to receptor phosphorylation and, in addition, to enhanced integrin-mediated adhesion of B cells to both VCAM-1 and fibronectin. Importantly, the c-Met ligand HGF/SF is produced at high levels by tonsillar stromal cells thus providing signals for the regulation of adhesion and migration within the lymphoid microenvironment. 相似文献
7.
Ioannis Mantas Mark J. Millan Benjamin Di Cara Lucianne Groenink Sylvie Veiga Laetitia Cistarelli Mauricette Brocco Marc Bertrand Per Svenningsson Xiaoqun Zhang 《International journal of molecular sciences》2021,22(16)
Trace Amine-Associated Receptor 1 (TAAR1) is a potential target for the treatment of depression and other CNS disorders. However, the precise functional roles of TAAR1 to the actions of clinically used antidepressants remains unclear. Herein, we addressed these issues employing the TAAR1 agonist, o-phenyl-iodotyramine (o-PIT), together with TAAR1-knockout (KO) mice. Irrespective of genotype, systemic administration of o-PIT led to a similar increase in mouse brain concentrations. Consistent with the observation of a high density of TAAR1 in the medial preoptic area, o-PIT-induced hypothermia was significantly reduced in TAAR1-KO mice. Furthermore, the inhibition of a prepulse inhibition response by o-PIT, as well as its induction of striatal tyrosine hydroxylase phosphorylation and elevation of extracellular DA in prefrontal cortex, were all reduced in TAAR1-KO compared to wildtype mice. O-PIT was active in both forced-swim and marble-burying tests, and its effects were significantly blunted in TAAR1-KO mice. Conversely, the actions on behaviour and prefrontal cortex dialysis of a broad suite of clinically used antidepressants were unaffected in TAAR1-KO mice. In conclusion, o-PIT is a useful tool for exploring the hypothermic and other functional antidepressant roles of TAAR1. By contrast, clinically used antidepressants do not require TAAR1 for expression of their antidepressant properties. 相似文献
1