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Abstract

Polyurethanes (PU) foams with titanium particles (Ti) were prepared with castor oil (CO) and isophorone diisocyanate (IPDI) as polymeric matrix, and 1, 3 and 5?wt.% of Ti. Composites were physicochemically and mechanically characterized and their biocompatibility assessed using human dental pulp stem cells (HDPSC). PU synthesis was confirmed by FTIR, but the presence of Ti was detected by RAMAN, X-ray diffraction (peak at 2θ?=?40.2°) and by EDX-mapping. Materials showed three decomposition temperatures between 300?°C and 500?°C and their decomposition were not catalyzed by Ti particles. Compressive modulus (164–846?kPa), compressive strength (12.9–116.7?kPa) and density (128–240?kg/m3) tend to increase with Ti concentration but porosity was reduced (87% to 80%). Composites’ foams were fully degraded in acid and oxidative media while remained stable in distilled water. HDPSC viability on all composites was higher than 80% up to 14?days while proliferation dropped up to 60% at 21?days. Overall, these results suggest that these foams can be used as scaffolds for bone tissue regeneration.  相似文献   
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Background: The purpose of this research is to discover whether measurement of cervical length and cervical volume at term is helpful in predicting the onset of labor in VBAC candidates.Methods: Transvaginal sonographic evaluations of the cervixes of pregnant women who desired to undergo VBAC were performed between 36 - 40 weeks gestation. Clinical information such as labor onset time, gestational age at delivery and delivery mode was gathered from medical records.Results: A total of 514 pregnant women participated in this study. Cervical length was significantly longer in the group that delivered 7 days or more after measurement than in the group that delivered within 7 days of measurement (43±0.77 cm vs. 2.99±0.72 cm, p< 0.001). Cervical volume was significantly larger in the group that delivered at and after 7 days than in the group that delivered within 7 days (29.21±11.62 cm3 vs. 34.07±13.41 cm3, p=0.014). The cervical length ROC curve was significantly more predictive than the cervical volume ROC curve (AUC: 0.711 vs 0.594, p= 0.001). There were no significant differences between the combined cervical length/volume ROC curve and the cervical length ROC curve alone (p= 0.565). The AUC of the cervical length ROC curve to predict postterm pregnancy was 0.729.Conclusion: Measuring cervical length is helpful in predicting the onset of spontaneous labor within 7 days and posterm delivery in VBAC candidates.  相似文献   
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Simple bone cyst (SBC) also known as unicameral bone cyst is a benign, radiolucent bone lesion that is seen commonly in childhood. These lesions are usually found incidentally although pain and swelling can be seen. The most common complication is a pathological fracture, and this is often the cause of presentation. Here, we present a 22-year-old male with right lower quadrant pain due to SBC related pathological fracture of right iliac bone which is mimicking acute appendicitis.  相似文献   
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