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181.
Shibli JA Grassi S de Figueiredo LC Feres M Iezzi G Piattelli A 《Implant dentistry》2007,16(3):252-259
PURPOSE: The aim of this study was to evaluate the influence of oxidized surface on bone-to-implant contact percentage (BIC%) as well as the bone density within the threads area (BD%) in human bone after 2 months of unloaded healing. MATERIALS: Seven subjects (mean age 45.57 +/- 10.45 years) received 2 micro-implants each during conventional implant surgery in the posterior maxilla. The implants that presented turned and oxidized surfaces served as control and test, respectively. After the healing period, the implants and the surrounding tissue were removed and prepared for ground sectioning and analysis. RESULTS: Two turned implants were found to be clinically unstable at the time of retrieval. Histometric evaluation showed that the mean of BIC% was 17.40 +/- 14.16% and 32.19 +/- 15.68% to turned and oxidized surfaces, respectively. The BD% was 22.13 +/- 19.06% for turned surface and 50.40 +/- 18.35% for oxidized surface. CONCLUSION: The histologic data from this preliminary study suggest that the oxidized micro-implants surface presented better mean values of BIC% and BD% than turned micro-implants after a short healing time. 相似文献
182.
PURPOSE: This study was an immunohistochemical evaluation of microvessel density (MVD) in sinus augmentation procedures with autologous bone and anorganic bone (Bio-Oss). MATERIALS AND METHODS: Twenty-four patients (14 men and 10 women - mean age of 48 years with a range from 34 to 53 years) participated in this study. All the patients presented a maxillary partial unilateral edentulism involving the premolar/molar areas, with a residual alveolar ridge height of about 4 to 5 mm. Twelve patients received sinus augmentation procedures with 100% autologous bone; 100% Bio-Oss was used in the other 12 patients. Endosseous implants were inserted after a mean period of 3 months. As control, the portions of preexisting subantral bone were used. The mean value of the MVD in control bone was 23.4 +/- 1.3. The mean value of the MVD in the sinuses augmented with autologous bone was 29.0 +/- 2.4. The mean value of the MVD in the sinuses augmented with Bio-Oss was 23.8 +/- 2.2. RESULTS: The statistical analysis showed that the differences of the MVD between control bone and sinuses augmented with Bio-Oss were not statistically significant (P = 0.52), while the difference of the MVD between sinuses augmented with autologous bone and those augmented with Bio-Oss was statistically significant (P = 0.0008). CONCLUSIONS: Autologous bone may act not only as a passive filling material in bone defects but may also release osteogenic growth factors; and particles of autologous bone seem to contain vital osteoprogenitor cells. 相似文献
183.
Maspin expression in oral squamous cell carcinoma 总被引:1,自引:0,他引:1
Iezzi G Piattelli A Rubini C Goteri G Artese L Perrotti V Carinci F 《The Journal of craniofacial surgery》2007,18(5):1039-1043
Maspin (mammary serine protease inhibitor) is a member of the serpin superfamily of protease inhibitors and it has a role as a tumor suppressor. Maspin has been reported to be important in processes relevant to tumor growth and metastasis such as cell invasion, angiogenesis, and apoptosis. A high expression of maspin was correlated with better rates of survival and absence of nodal metastases in head and neck squamous cell carcinoma. In contrast, some studies have shown that maspin overexpression is correlated with a poor prognosis in pancreatic and ovarian cancers and in lung adenocarcinoma. The aim of this study was an immunohistochemical evaluation of the maspin expression in oral squamous cell carcinoma and thus 89 patients were evaluated. Maspin expression in oral squamous cell carcinoma was significantly associated with the tumor differentiation grade (chi test: P = 0.0318) and the lymph node status (chi test: P < 0.005), but not with the tumor stage (chi test: P = 0.666). Metastatic involvement of lymph nodes was observed more frequently in maspin-negative cases than in tumors with more than 5% of positive cells (P = 0.0024). The present results confirm that maspin expression predicts a better prognosis in oral squamous cell carcinoma and that maspin probably plays a role in tumor progression. 相似文献
184.
Cristina Partenope Gabriella Pozzobon Giovanna Weber Fernando Carceller Assunta Albanese 《Pediatric blood & cancer》2023,70(3):e30168
Aims
This study analysed the clinical features of a cohort of children with intracranial germ cell tumours (IC-GCTs). We retrospectively reviewed timelag between symptoms onset, clinic-radiological findings, diagnosis and outcomes.Methods
Symptoms at diagnosis were divided into four groups: (1) raised intracranial pressure (RICP); (2) visual impairment; (3) endocrinopathies; (4) other. Total diagnostic interval (TDI), defined as the interval between symptom onset (including retrospective recall of symptoms) and definitive diagnosis of IC-GCT, was calculated and compared to survival rates.Results
Our cohort included 55 children with median follow-up of 78.9 months (0.5–249.9). The majority (63.6%) had germinomas and 10.9% were metastatic at diagnosis. IC-GCTs were suprasellar (41.8%), pineal (36.4%), bifocal (12.7%) or in atypical sites (9.1%). The most common presenting symptoms were related to RICP (43.6%); however, by the time of tumour diagnosis, 50.9% of patients had developed endocrine dysfunctions. All pineal GCTs manifested with RICP or visual impairment. All suprasellar GCTs presented with endocrinopathies. TDI ranged between 0.25 and 58.5 months (median 4 months). Pineal GCTs had the shortest TDI (median TDI 1 month versus 24 months in suprasellar GCTs, p < .001). TDI > 6 months was observed in 47.3% of patients and was significantly associated with endocrine presenting symptoms. No statistically significant difference was found in progression-free survival and overall survival between patients with TDI > 6 months and with TDI ≤ 6 months.Conclusion
Approximately half of the IC-GCT patients in this cohort had TDI > 6 months. These presented mostly with endocrine deficits. TDI > 6 months was not associated with increased relapse or mortality rates. 相似文献185.
Gembillo Guido Siligato Rossella Cernaro Valeria Satta Ersilia Conti Giovanni Salvo Antonino Romeo Adolfo Calabrese Vincenzo Sposito Giovanna Ferlazzo Guido Santoro Domenico 《International urology and nephrology》2022,54(2):395-403
International Urology and Nephrology - Inflammation, oxidative stress (OS), atherosclerosis and resistant hypertension (RH) are common features of chronic kidney disease (CKD) leading to a higher... 相似文献
186.
Borrelli Enrico Grosso Domenico Vella Giovanna Sacconi Riccardo Querques Lea Zucchiatti Ilaria Prascina Francesco Bandello Francesco Querques Giuseppe 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(12):2655-2660
Graefe's Archive for Clinical and Experimental Ophthalmology - To quantify the shrinking in outpatient and intravitreal injections’ volumes in a tertiary referral retina unit secondary to... 相似文献
187.
188.
Luigi Angelo Vaira Claire Hopkins Giovanni Salzano Marzia Petrocelli Andrea Melis Marco Cucurullo Mario Ferrari Laura Gagliardini Carlotta Pipolo Giovanna Deiana Vito Fiore Andrea De Vito Nicola Turra Sara Canu Angelantonio Maglio Antonello Serra Francesco Bussu Giordano Madeddu Sergio Babudieri Alessandro Giuseppe Fois Pietro Pirina Francesco A. Salzano Pierluigi De Riu Federico Biglioli Giacomo De Riu 《Head & neck》2020,42(7):1560-1569
189.