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41.
The purpose of this study was to evaluate the influence of the oxidized surface on bone-to-implant contact (BIC%), the bone density in the threaded area (BA%), as well as the bone density outside the threaded area (BD%) in human jaws after 2 months of unloaded healing. Thirteen subjects (mean age 42.61 +/- 6.15 years) received two microimplants (2.5 mm diameter and 6 mm length) each, during conventional mandible or maxilla implant surgery. The microimplants with commercially pure titanium surfaces (machined) and oxidized surfaces served as the control and test surfaces, respectively. After 2 months, the microimplants and the surrounding tissue were removed and prepared for histomorphometric analysis. All microimplants, except two machined and one oxidized microimplant surfaces, were found to be clinically stable after the healing period. Histometric evaluation indicated that the mean BIC% was (21.71 +/- 13.11)% and (39.04 +/- 15.75)% for machined and oxidized microimplant surfaces, respectively. The BD% was higher for the oxidized surface, although there was no difference for maxilla and mandible. The oxidized surface impacted the BA% for the type-IV bone. Data suggest that the oxidized surface presented a higher bone-to-implant contact rate compared with machined surfaces under unloaded conditions, after a healing period of 2 months.  相似文献   
42.
Clinical practice guidelines (CPGs) contain evidence‐based recommendations to guide clinical care, policy development, and quality of care improvement. A recent systematic review of epilepsy guidelines identified considerable variability in the quality of available guidelines. Although excellent frameworks for CPG development exist, processes are not followed uniformly internationally, and resources to develop CPGs may be limited in certain settings. An International League Against Epilepsy (ILAE) working group was charged with proposing methodology to guide the development of future epilepsy‐specific CPGs. A comprehensive literature search (1985–2014) identified articles related to CPG development and handbooks. Guideline handbooks were included if they were publicly available, and if their methodology had been used to develop CPGs. The working group's expertise also informed the creation of methodologies and processes to develop future CPGs for the ILAE. Five handbooks from North America (American Academy of Neurology), Europe (Scottish Intercollegiate Guidelines Network & National Institute for Health and Care Excellence), Australia (National Health and Medical Research Council), World Health Organization (WHO), and additional references were identified to produce evidence‐based, consensus‐driven methodology for development of epilepsy‐specific CPGs. Key components of CPG development include the following: identifying the topic and defining the scope; establishing a working group; identifying and evaluating the evidence; formulating recommendations and determining strength of recommendations; obtaining peer reviews; dissemination, implementation, and auditing; and updating and retiring the CPG. A practical handbook and toolkit was developed. The resulting CPG development toolkit should facilitate the development of high‐quality ILAE CPGs to improve the care of persons with epilepsy.  相似文献   
43.

Introduction

Endometriosis represents an important clinical problem in women of reproductive age with high impact on quality of life, work productivity and health care management. The aim of this study is to define the role of 3 T magnetom system MRI in the evaluation of endometriosis.

Materials and methods

Forty-six women, with transvaginal (TV) ultrasound examination positive for endometriosis, with pelvic pain, or infertile underwent an MR 3.0 T examination with the following protocol: T2 weighted FRFSE HR sequences, T2 weighted FRFSE HR CUBE 3D sequences, T1 w FSE sequences, LAVA-flex sequences. Pelvic anatomy, macroscopic endometriosis implants, deep endometriosis implants, fallopian tube involvement, adhesions presence, fluid effusion in Douglas pouch, uterus and kidney pathologies or anomalies associated and sacral nervous routes were considered by two radiologists in consensus. Laparoscopy was considered the gold standard.

Results

MRI imaging diagnosed deep endometriosis in 22/46 patients, endometriomas not associated to deep implants in 9/46 patients, 15/46 patients resulted negative for endometriosis, 11 of 22 patients with deep endometriosis reported ovarian endometriosis cyst. We obtained high percentages of sensibility (96.97%), specificity (100.00%), VPP (100.00%), VPN (92.86%).

Conclusion

Pelvic MRI performed with 3 T system guarantees high spatial and contrast resolution, providing accurate information about endometriosis implants, with a good pre-surgery mapping of the lesions involving both bowels and bladder surface and recto-uterine ligaments.  相似文献   
44.

Background

Simple tumor enucleation (TE) showed excellent oncologic results in large retrospective series. No study has compared oncologic outcomes after TE and radical nephrectomy (RN) for the treatment of pT1 renal cell carcinoma (RCC). The aim of the present study is to compare the oncologic outcomes after TE and RN in pT1 RCCs.

Methods

We retrospectively analyzed 475 patients who underwent TE or RN for pT1 RCC, N0, M0, between 1995 and 2007. TE was performed in 332 patients and RN in 143. Local recurrence, progression-free survival (PFS), and cancer-specific survival (CSS) were the main outcomes of this study. The Kaplan-Meier method was used to calculate survival functions, and differences were assessed with the log rank statistic. Univariate and multivariate Cox regression models were also used.

Results

The 5- and 10-year PFS estimates were 91.3 and 88.7% after RN and 95.3 and 92.8% after TE (P?=?NS), respectively. The 5- and 10-year CSS estimates were 92.1 and 89.4% after RN and 94.4% (5- and 10-year CSS) after TE (P?=?NS), respectively. No statistically significant differences between RN and TE were found after adjusting CSS probabilities according to age at surgery, grade, stage, or clear cell subtype. Surgical treatment was not a predictor of PFS or CSS by both univariate and multivariate analyses. The potential limitation of this study is that the data originate from a retrospective review.

Conclusions

TE can achieve oncologic results similar to those of RN for the treatment of pT1 RCCs, provided tumors are carefully selected on the basis of their safe and complete removal.  相似文献   
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47.

Objectives

The aim of this study is to evaluate the distribution of the filler size along with the zeta potential, and the integrity of silane-bonded filler surface in different types of restorative dental composites as a function of the material age condition.

Materials and methods

Filtek P60 (hybrid composite), Filtek Z250 (small-particle filled composite), Filtek Z350XT (nanofilled composite), and Filtek Silorane (silorane composite) (3M ESPE) were tested at different stage condition (i.e., fresh/new, aged, and expired). Composites were submitted to an accelerated aging protocol (Arrhenius model). Specimens were obtained by first diluting each composite specimen in ethanol and then dispersed in potassium chloride solution (0.001 mol%). Composite fillers were characterized for their zeta potential, mean particle size, size distribution, via poly-dispersion dynamic light scattering. The integrity of the silane-bonded surface of the fillers was characterized by FTIR.

Results

The material age influenced significantly the outcomes; Zeta potential, filler characteristics, and silane integrity varied both after aging and expiration. Silorane presented the broadest filler distribution and lowest zeta potential. Nanofilled and silorane composites exhibited decreased peak intensities in the FTIR analysis, indicating a deficiency of the silane integrity after aging or expiry time.

Conclusion

Regardless to the material condition, the hybrid and the small-particle-filled composites were more stable overtime as no significant alteration in filler size distribution, diameter, and zeta potential occurred. A deficiency in the silane integrity in the nanofilled and silorane composites seems to be affected by the material stage condition.

Clinical significance

The materials conditions tested in this study influenced the filler size distribution, the zeta potential, and integrity of the silane adsorbed on fillers in the nanofilled and silorane composites. Thus, this may result in a decrease of the clinical performance of aforementioned composites, in particular, if these are used after inappropriate storage conditions.
  相似文献   
48.

Objectives

The prognostic value of free to total PSA ratio (F/T PSA) in patients eligible for radical prostatectomy (RP) is controversial. The aim of the present study was to evaluate correlation of F/T PSA with tumor extracapsular extension (ECE) and biochemical recurrence (BR) at long-term follow-up.

Patient and methods

Clinical and pathological data were prospectively gathered from 200 patients treated with RP for clinically localized prostate cancer (PCa) and PSA between 4 and 10?ng/mL. Correlations of preoperative variables including F/T PSA with ECE and BR were evaluated with uni- and multivariate analysis. Adjunctive analyses evaluated the association of PSA F/T with other pathological results. The relationship between preoperative F/T PSA and BR was also assessed with Kaplan?CMeier survival analysis.

Results

Lower F/T PSA was significantly correlated with ECE (p?=?0.0063), higher GS (p?=?0.0054), and seminal vesicles involvement (p?=?0.0047). The F/T PSA value of 14% provided the greatest discrimination in predicting ECE. At multivariate analysis, F/T PSA did not achieve the statistical significance for predicting ECE independently. At a mean (median, range) follow-up of 52 (48, 14?C116) months, preoperative F/T PSA resulted significantly correlated with BR (p?=?0.001). At the Kaplan?CMeier survival analysis, the 5-year BR free survival rate resulted 89.3 and 68.9% in the group with F/T PSA?>14 and ??14?ng/mL, respectively (log rank p?=?0.0022). At Cox proportional hazard model, only ECE resulted an independent predictor of BR (R?=?2.646, p?=?0.037).

Conclusion

In patients with clinically localized PCa and PSA 4?C10?ng/ml, lower F/T PSA was significantly associated with ECE, other adverse pathologic features, and with BR at the long-term follow-up, but only ECE resulted an independent predictor of BR in our series.  相似文献   
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