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101.
Unlü RE Orbay H Ylmaz AD Aksoy E Uraloğlu M Sensöz O 《The Journal of craniofacial surgery》2007,18(3):661-664
The main principle of reconstructive surgery is replacement of the defective tissues with like tissues. A full-thickness defect of the nasal ala should be reconstructed in three layers: innermost mucosal layer, outermost skin, and the cartilage in-between. The aim of this study is to describe a technique for single-stage, three-layer reconstruction of the full-thickness ala nasi defects. This technique was used on three patients with tumors involving the nasal ala. Resulting full-thickness defects are reconstructed with a mucocartilaginous turnover flap planned from the contralateral side. Aesthetically acceptable results are obtained without the compromise of the nasal airway and with minimal donor site morbidity. None of the patients requested a revision operation. In conclusion, this is a novel technique with minimal donor site morbidity and good postoperative results. Moreover, lost tissues are replaced with exactly the same kind of tissues. 相似文献
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Korasli D Ziraman F Ozyurt P Cehreli SB 《Journal of the American Dental Association (1939)》2007,138(5):634-640
BACKGROUND: The authors evaluated the coronal marginal leakage of endodontically treated teeth bonded with four self-etching adhesives and one total-etch adhesive system. MATERIALS AND METHODS: The investigators prepared Class II cavities in 60 extracted human premolars. They performed conventional endodontic therapy using a resin-based sealer and gutta-percha points. They randomly assigned each tooth to a group receiving one of the following adhesives: Adper Prompt L-Pop (3M ESPE, Seefeld, Germany), Clearfil SE Bond (Kuraray, Osaka, Japan), FL Bond (Shofu, Kyoto, Japan), Single Bond (3M ESPE) or Xeno III (Dentsply De Trey, Konstanz, Germany). They restored all teeth with resin-based composite material (Z250, 3M ESPE). Specimens underwent thermocycling and dye penetration and were sectioned longitudinally. The authors photographed the sections under a stereomicroscope. They transferred the images to an IBM-compatible personal computer for quantitative assessment of dye penetration using image analysis software. They analyzed data by means of Kruskal-Wallis and Mann-Whitney U tests (P = .05) and evaluated two specimens from each group under scanning electron microscopy. RESULTS: None of the tested self-etch adhesives completely eliminated microleakage. Dye leakage was restricted to the coronal cavity walls; it did not migrate toward the pulp chamber or toward the root canal. Single Bond and Clearfil SE Bond showed significantly lower dye penetration values at occlusal and gingival margins. CONCLUSIONS: The coronal sealing performance of the tested self-etch adhesive systems in endodontically treated teeth was material-dependent. The use of Clearfil SE Bond in such teeth can help achieve a marginal seal comparable to that achieved with Single Bond. 相似文献
104.
Verena Fischer Deniz Ragipoglu Johanna Diedrich Lena Steppe Anne Dudeck Konrad Schütze Miriam Kalbitz Florian Gebhard Melanie Haffner-Luntzer Anita Ignatius 《Journal of bone and mineral research》2022,37(1):137-151
Mast cells are important tissue-resident sensor and effector immune cells but also play a major role in osteoporosis development. Mast cells are increased in numbers in the bone marrow of postmenopausal osteoporotic patients, and mast cell–deficient mice are protected from ovariectomy (OVX)-induced bone loss. In this study, we showed that mast cell–deficient Mcpt5-Cre R-DTA mice were protected from OVX-induced disturbed fracture healing, indicating a critical role for mast cells in the pathomechanisms of impaired bone repair under estrogen-deficient conditions. We revealed that mast cells trigger the fracture-induced inflammatory response by releasing inflammatory mediators, including interleukin-6, midkine (Mdk), and C-X-C motif chemokine ligand 10 (CXCL10), and promote neutrophil infiltration into the fracture site in OVX mice. Furthermore, mast cells were responsible for reduced osteoblast and increased osteoclast activities in OVX mice callus, as well as increased receptor activator of NF-κB ligand serum levels in OVX mice. Additional in vitro studies with human cells showed that mast cells stimulate osteoclastogenesis by releasing the osteoclastogenic mediators Mdk and CXCL10 in an estrogen-dependent manner, which was mediated via the estrogen receptor alpha on mast cells. In conclusion, mast cells negatively affect the healing of bone fractures under estrogen-deficient conditions. Hence, targeting mast cells might provide a therapeutic strategy to improve disturbed bone repair in postmenopausal osteoporosis. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献
105.
Assessment of left ventricular diastolic function with Doppler tissue imaging: effects of preload and place of measurements 总被引:6,自引:2,他引:6
Dincer I Kumbasar D Nergisoglu G Atmaca Y Kutlay S Akyurek O Sayin T Erol C Oral D 《The international journal of cardiovascular imaging》2002,18(3):155-160
Mitral inflow velocities are widely used for the evaluation of left ventricular (LV) diastolic function. However, they are closely affected by other factors such as preload. The purpose of this study was to evaluate the usefulness of tissue Doppler velocities obtained from the mitral annulus for the evaluation of ventricular relaxation in patients under different loading conditions. We also evaluated the effect of preload at different sides on the mitral annulus. The study population consisted of 62 consecutive patients (38 male, 24 female with a mean age of 42 ± 13 years) who have undergone hemodialysis. Both mitral inflow velocities (E wave, A wave, E wave deceleration time and isovolumetric relaxation time) and mitral annulus tissue Doppler velocities (E, A) from the septal, lateral, anterior, posterolateral and inferior sides of the mitral annulus were measured immediately before and after hemodialysis. Mitral inflow E and A wave velocities and E/A ratio decreased significantly (p < 0.001, p = 0.007, p < 0.001, respectively) after hemodialysis. Mitral annulus E wave velocities and E/A ratios obtained from five different sides of the annulus also changed significantly (p < 0.001 for all); however, there was no change in the A wave velocity (p > 0.05 for all) after hemodialysis. The decrease in E wave and E/A ratio in mitral inflow measurements and E velocities and E/A ratios in tissue Doppler measurements were correlated with the amount of fluid extracted (for mitral inflow E wave, r = 0.392, p = 0.002 and E/A ratio, r = 0.280 and p = 0.027; for lateral side E, r = 0.329, p = 0.009 and E/A ratio, r = 0.286, p = 0.04; for septal side E, r = 0.376, p = 0.003 and E/A ratio, r = 0.297, p = 0.019; for anterior side E, r = 0.342, p = 0.007 and E/A ratio, r = 0.268, p = 0.035; for posterolateral side E, r = 0.423, p = 0.001 and E/A ratio, r = 0.343, p = 0.007; and for inferior side E, r = 0.326, p = 0.01 and E/A ratio, r = 0.278, p = 0.029). We conclude that mitral annular velocities obtained by tissue Doppler are preload dependent parameters for the evaluation of LV diastolic function. 相似文献
106.
Abdulkadir Bedirli Deniz Yucel Burcu Ekim 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2014,18(3)
Background and Objectives:
Bowel anastomosis after anterior resection is one of the most difficult tasks to perform during laparoscopic colorectal surgery. This study aims to evaluate a new feasible and safe intracorporeal anastomosis technique after laparoscopic left-sided colon or rectum resection in a pig model.Methods:
The technique was evaluated in 5 pigs. The OrVil device (Covidien, Mansfield, Massachusetts) was inserted into the anus and advanced proximally to the rectum. A 0.5-cm incision was made in the sigmoid colon, and the 2 sutures attached to its delivery tube were cut. After the delivery tube was evacuated through the anus, the tip of the anvil was removed through the perforation. The sigmoid colon was transected just distal to the perforation with an endoscopic linear stapler. The rectosigmoid segment to be resected was removed through the anus with a grasper, and distal transection was performed. A 25-mm circular stapler was inserted and combined with the anvil, and end-to-side intracorporeal anastomosis was then performed.Results:
We performed the technique in 5 pigs. Anastomosis required an average of 12 minutes. We observed that the proximal and distal donuts were completely removed in all pigs. No anastomotic air leakage was observed in any of the animals.Conclusion:
This study shows the efficacy and safety of intracorporeal anastomosis with the OrVil device after laparoscopic anterior resection. 相似文献107.
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