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991.
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Odontology - The purpose of this study was to investigate whether the root perforation repair with mineral aggregate-based cements affects the retention of customized fiberglass posts to bovine...  相似文献   
993.
We report on seven cases of congenital radio-ulnar synostosis (RUS). Five were found in the same family and two were sporadic. In six the synostosis was bilateral and consistently involved the proximal end of the radius and ulna. In the familial cases the anomaly was inherited as an autosomal dominant trait and was associated with a Dubois sign and relative shortness of metacarpals number 4 and 5 in two patients, and of number 2 in another patient, and of all phalanges of the 5th fingers. These observations suggest involvement of an ulnar developmental field. RUS does not seem to be rare in the Sicilian population. Am. J. Med. Genet. 68:127–134, 1997 © 1997 Wiley-Liss, Inc.  相似文献   
994.
Fabrication of flower-like nanostructures are gaining attention because of their high surface/volume ratio and extensive adsorption capacity. In the present investigation, flower-shaped, autofluorescent silver-silica (Ag-SiO2) hybrid nanoparticles have been fabricated exploiting diatoms as a source of nanosilica. Two different species of Gedaniella including G. flavovirens and G. mutabilis showed their efficacy in synthesizing fluorescent Ag-SiO2 nanoflowers (NFs) and nanospheres (NSs) against 9 mM silver nitrate solution, respectively. The biogenic nanoconjugate (Ag-SiO2) was characterized by Uv-vis spectroscopy, energy dispersive X-ray spectroscopy (EDS), scanning (SEM) and transmission (TEM) electron microscopy. Production of Ag-SiO2 hybrid nanoparticle was confirmed by observing both Ag and Si signals from a single nanoparticle in an EDS study. The broad and single absorption band at ~420 nm in Uv-vis spectroscopy confirmed proper miscibility and production of hybrid nanoparticles. The Ag-SiO2 nanohybrids revealed autofluorescent property under the blue light region (excitation ~450–490 nm). SEM images of particles synthesized by G. flavovirens revealed the production of microscopic flower shaped Ag-SiO2 particles with several layers of petals. A TEM study confirmed that the synthesized Ag-SiO2 NFs are variable in size with 100–500 nm in diameter. Decolorization of methylene blue after exposure to Ag-SiO2 particles confirmed catalytic activity of synthesized nanostructures. This eco-friendly method provides a new dimension in nanobiotechnology for biogenesis of such hierarchical nanostructure in a cost-effective way.  相似文献   
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To investigate the influence of the wars in Croatia and Bosnia and Herzegovina on incidence and perinatal outcome of singleton preterm births at the Department of Gynecology and Obstetrics in the Split University Hospital. Data were collected by reviewing patients’ files at the Department of Gynecology and Obstetrics from three periods: the three years before the war (1988–1990), during the war (1992–1994), and after the war (1996–1998). A total of 2,358 patients’ files of singleton preterm delivery were analyzed. Singleton preterm delivery rate decreased during the war (5.02%) and post-war period (4.74%) compared to the pre-war period (6.19%). Stillbirth and early neonatal mortality rates of singleton premature babies significantly increased during the war to 226%, compared to 193% before the war and 134% after the war. Early neonatal mortality rate was 215% during the war, 209% in the pre-war period, and 156% after the war. Despite the continuous decrease in singleton preterm birth rate throughout the observed periods, the increase in stillbirth rate and early neonatal mortality rate during the war might have been caused by the war. This may be due to primary gynecological care being inadequate for many pregnant women.  相似文献   
998.
1. We compared the changes in binding energy generated by two mutations that shift in divergent directions the constitutive activity of the human beta(2) adrenergic receptor (beta(2)AR). 2. A constitutively activating mutant (CAM) and the double alanine replacement (AA mutant) of catechol-binding serines (S204A, S207A) in helix 5 were stably expressed in CHO cell lines, and used to measure the binding affinities of more than 40 adrenergic ligands. Moreover, the efficacy of the same group of compounds was determined as intrinsic activity for maximal adenylyl cyclase stimulation in wild-type beta(2)AR. 3. Although the two mutations had opposite effects on ligand affinity, the extents of change were in both cases largely correlated with the degree of ligand efficacy. This was particularly evident if the extra loss of binding energy due to hydrogen bond deletion in the AA mutant was taken into account. Thus the data demonstrate that there is an overall linkage between the configuration of the binding pocket and the intrinsic equilibrium between active and inactive receptor forms. 4. We also found that AA mutation-induced affinity changes for catecholamine congeners gradually lacking ethanolamine substituents were linearly correlated to the loss of affinity that such modifications of the ligand cause for wild-type receptor. This indicates that the strength of bonds between catechol ring and helix 5 is critically dependent on the rest of interactions of the beta-ethanolamine tail with other residues of the beta(2)-AR binding pocket.  相似文献   
999.
A direct correlation has been reported between excessive fat intake and the development and progression of various enteropathies. Plant foods may contain bioactive compounds and non-digestible dietary fiber, with potential to improve intestinal health. Chia is a good source of dietary fiber and bioactive compounds. Our study evaluated the role of chia flour associated with a high-fat diet (HFD) on colon histomorphometry, intestinal functionality and intestinal microbiome composition and function in Wistar rats. The study used 32 young male rats separated into four groups to receive a standard diet (SD) or HFD, with or without chia, for 35 days. At the end of the study, the cecum, cecal content and duodenum were collected. The consumption of chia increased the production of short-chain fatty acids and improved fecal moisture. Chia consumption improved the circular muscle layer in the SD group. The diversity and abundance of intestinal bacteria were not affected, but increased richness was observed in the microbiome of the SD+chia group. Moreover, chia consumption decreased the expression of proteins involved in intestinal functionality. Chia consumption improved intestinal morphology and functionality in young Wistar rats but was insufficient to promote significant changes in the intestinal microbiome in a short term of 35 days.  相似文献   
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