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The purpose of this in vitro study was to compare both apical and coronal dye penetration when Ketac-Endo and AH-26 sealers were used with laterally condensed gutta percha. Crowns were removed from 28 teeth and the root canals were biomechanically prepared. The teeth were divided into two groups of 12-teeth each and a control group of 4 teeth. Root canals in the two experimental groups were filled with laterally condensed gutta percha and either Ketac-Endo or AH-26 sealer. The Ketac-Endo group had the coronal 3 mm of gutta percha and sealer removed and the resultant cavity was filled with Ketac-Endo alone. After the sealers had set, the root surfaces were coated with nail varnish except at the apex and at the coronal end. Positive controls had no root fillings and were coated with nail varnish in the same manner while the negative controls were sealed apically and coronally with Cavit prior to sealing the entire external root surface with nail varnish. Specimens were placed in 2% methylene blue dye in a vacuum of 660 mm of mercury for five minutes and then left immersed for a further two days. The roots were vertically sectioned to determine the following mean levels of dye penetration: Ketac-Endo, 1.08 mm apically and 6.29 mm coronally; AH-26, 0.75 mm apically and 6.67 mm coronally. Positive controls had total leakage and negative controls had no leakage. This study demonstrated that the apical and coronal seals obtained with Ketac-Endo and AH-26 were not significantly different although the apical seal obtained with each material was significantly better than the corresponding coronal seal. 相似文献
93.
Interactions of L-triiodothyronine (T3) in adult rat cerebrocortical synaptosomes were studied in vitro. Scatchard plot analysis revealed two sets of T3 binding sites. The degree of saturation of T3 binding sites (putative receptor) correlated well with the dose-dependent inhibition of Na(+)-K(+)-ATPase activity in synaptosomes. The relative binding affinities and relative inhibition of enzyme activities for different TH analogues were L-T3 > T3-amine > TRIAC = L-T4 > r-T3 > T2 and L-T3 > T3-amine > TRIAC > L-T4 > r-T3 > T2, respectively. The present study demonstrates the nature of inhibition of synaptosomal Na(+)-K(+)-ATPase activity may be as a function of T3 occupancy of synaptosomal receptor sites in adult mammalian brain. 相似文献
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The purpose of this study was to evaluate the effect of redesigning the education program from individual instructional sessions to a format where the majority of instruction was provided through small group classes. Patient outcomes of lifestyle changes as evidenced by weight loss, improved glycemic control, adoption of a consistent pattern of blood glucose monitoring, and increased physical activity were evaluated using a physician satisfaction survey and a patient satisfaction and lifestyle change survey. The findings indicate that the changes in the education program accommodated a variety of needs; facilitated cost-effectiveness; were convenient for the patients, educators, and physicians; and still promoted adaptive lifestyle changes in behavior leading to improved glycemic control, increased levels of physical activity, and weight loss in persons with type 2 diabetes. 相似文献
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Glycogen in the placenta and its appendages is important for fetal well-being. The precise location of the glycogen stores, however, is unknown. This study was initiated to quantitate glycogen levels at well-defined sampling sites in more than 641 samples from 10 uncomplicated pregnancies and to correlate these glycogen levels with clinical and morphological variables. By biochemical assay, glycogen levels were greatest in the midumbilical cord section (29.08 +/- 1.18 mg/g dry wt) and lowest in the amnionic membrane (2.31 +/- 0.08 mg/g dry wt). Within the placental disk, parenchymal glycogen levels were greatest near the cord insertion (9.31 +/- 2.68 mg/g dry wt) and lowest at the periphery (5.71 +/- 1.14 mg/g dry wt). The midumbilical cord glycogen level showed strong direct correlations (P < .001) with birth weight, umbilical cord weight, and total calculated umbilical cord glycogen and somewhat lower but significant (P < .037) direct correlations with the calculated mean umbilical cord glycogen level, total calculated placental glycogen content, and placental weight. The glycogen level in the middisk parenchymal section from the fetal surface correlated directly with gestational age. Periodic acid-Schiff stains showed that magenta glycogen granules were most abundant in the cytoplasm of the vascular smooth muscle cells. These data show significant variations in glycogen levels among sampling sites. Definition of the precise sampling site is important for clinicopathologic studies of placental glycogen and for interstudy correlations. 相似文献
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