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Titanium alloys are the most commonly used dental and orthopedic implant materials due to their proven biocompatibility and mechanical properties. The native oxide layer (TiO2 layer) formed on such Ti-based implants acts as the self-protecting layer against possible ion release. Increasing the oxide layer thickness further on such TiO2 implants even opens the triggering of the osseointegration process if the oxide layer is having a certain degree of roughness, preferably higher. This work reports a novel photocatalytic patterning of sputter deposited TiO2 layers with flower-like Au structures to enhance the early osteoblastic activity. The prepared hierarchical Au structures, composed of micro- and nanoscale features on the top, lead to improved number of filopodia formation. This suggest that proposed Au–TiO2 surface may foster the cell attachment and as well as cell proliferation.

Flower-like hierarchical Au structures, composed of micro- and nanoscale features, lead to higher number of filopodia formation on TiO2 thin films.  相似文献   
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PURPOSE: To determine whether spectral Doppler measurements obtained from bilateral uterine, arcuate, radial, and spiral arteries in early gestation correlate with adverse pregnancy outcome. METHODS: One hundred five pregnant women underwent transvaginal Doppler sonographic examination of uteroplacental circulation at 6-12 weeks' gestation. Resistance index (RI) and pulsatility index (PI) of bilateral uterine, arcuate, radial, and spiral arteries were measured. Diameters of gestational sac (GS) and yolk sac, crown-rump length (CRL), GS-CRL difference, and GS/CRL ratio were also recorded. Correlation was made with pregnancy outcome. RESULTS: Sixteen women developed adverse pregnancy outcome. In these women, right uterine artery PI and RI were significantly higher than in women with normal obstetrical outcome. Spiral artery PI and RI values were also higher, but the difference was not statistically significant. GS-CRL difference, GS/CRL ratio, and yolk sac diameters were significantly lower in this group. CONCLUSION: Transvaginal Doppler examination can detect hemodynamic changes in uteroplacental circulation associated with subsequent adverse pregnancy outcome.  相似文献   
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A dystopic neurohypophysis was noted incidentally at autopsy in a 51 -year-old man with no endocrine abnormality. The dystopic gland was situated in the upper region of the tuber cinereum and macroscopically simulated a neoplasm. The pituitary fossa contained only anterior hypophyseal elements. Review of the literature disclosed 19 such cases discovered at autopsy; 11 occurred in normal individuals with no endocrine abnormality. Radiological study revealed 145 additional cases. Except for the 6 occurrences described in normal individuals, the rest occurred in patients with anterior pituitary dysfunction. No instance of isolated diabetes insipidus has been reported due to dystopia of the neurohypophysis. Dystopia of the neurohypophysis in normal individuals should be distinguished from those occurring in patients with anterior pituitary abnormalities. The former represent a true dystopia and are not associated with perinatal injury, in contrast to the latter, which are acquired dystopias secondary to regeneration of the neurohypophysis and are associated with perinatal injury. Although anterior and posterior pituitary glands are formed by appositional growth, their development and functional status are entirely independent. Finally, the most significant clinical feature of dystopic neurohypophysis is the absence of any related symptoms and this condition should always be considered in the clinical differential diagnosis of hypothalamic lesions. In such patients, a surgical procedure may be avoided because other hypothalamic lesions, such as hamartomas and astrocytomas, are more frequently symptomatic.  相似文献   
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