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Kibaek Lee Junjun Zhu Judy Shum Yongjie Zhang Satish C. Muluk Ankur Chandra Mark K. Eskandari Ender A. Finol 《Annals of biomedical engineering》2013,41(3):562-576
An abdominal aortic aneurysm (AAA) carries one of the highest mortality rates among vascular diseases when it ruptures. To predict the role of surface curvature in rupture risk assessment, a discriminatory analysis of aneurysm geometry characterization was conducted. Data was obtained from 205 patient-specific computed tomography image sets corresponding to three AAA population subgroups: patients under surveillance, those that underwent elective repair of the aneurysm, and those with an emergent repair. Each AAA was reconstructed and their surface curvatures estimated using the biquintic Hermite finite element method. Local surface curvatures were processed into ten global curvature indices. Statistical analysis of the data revealed that the L2-norm of the Gaussian and Mean surface curvatures can be utilized as classifiers of the three AAA population subgroups. The application of statistical machine learning on the curvature features yielded 85.5% accuracy in classifying electively and emergent repaired AAAs, compared to a 68.9% accuracy obtained by using maximum aneurysm diameter alone. Such combination of non-invasive geometric quantification and statistical machine learning methods can be used in a clinical setting to assess the risk of rupture of aneurysms during regular patient follow-ups. 相似文献
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Najmeh Movahhedian Maryam Paknahad Fatemeh Abbasinia Leila Khojatepour 《Journal of maxillofacial and oral surgery》2021,20(1):105
BackgroundThe sphenoid sinus is considered as the most variable pneumatized structure of the skull.PurposeThe aim of the present study was to determine the prevalence of the Onodi cell as well as to evaluate the relationship between the sphenoid sinus type of pneumatization and the presence of surrounding neurovascular protrusion using cone beam computed tomography (CBCT).MethodsThe CBCT images of 500 patients/996 sides [203 males (40.6%) and 297 females (59.4%)] were analyzed in this study. The type of sphenoid sinus pneumatization, prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusion and dehiscence, and also the frequency of Onodi cell were assessed.ResultsThe percentages of the conchal, presellar, sellar, postsellar (a), and postsellar (b) types of pneumatization were 1%, 11.5%, 35.5%, 38.9%, and 13.1%, respectively. The more the sphenoid sinuses pneumatized, the greater the frequency of ON and ICA protrusion and dehiscence of their wall to the sinus. The prevalence of Onodi cell was 38.8%. A significant correlation was found between ON dehiscence and the presence of Onodi cells.ConclusionThe present study demonstrated a significant relationship between the sinus type and frequency of neurovascular protrusions. Therefore, the sphenoid sinus extent of pneumatization might be useful in predicting the risk of iatrogenic damage to the surrounding structures. 相似文献
16.
PURPOSE
Debonding of a composite resin core of the fiber post often occurs at the interface between these two materials. The aim of this study was to evaluate the effects of different surface treatment methods on bond strength between fiber posts and composite core.MATERIALS AND METHODS
Sixty-four fiber posts were picked in two groups (Hetco and Exacto). Each group was further divided into four subgroups using different surface treatments: 1) silanization; 2) sandblasting; 3) Treatment with 24% H2O2, and 4) no treatment (control group). A cylindrical plexiglass matrix was placed around the post and filled with the core resin composite. Specimens were stored in 5000 thermal cycles between 5℃ and 55℃. Tensile bond strength (TBS) test and evaluation using stereomicroscope were performed on the specimen and the data were analyzed using two-way ANOVA, Post Hoc Scheffe tests and Fisher''s Exact Test (α=.05).RESULTS
There was a significant difference between the effect of different surface treatments on TBS (P<.001) but different brands of post (P=.743) and interaction between the brand of post and surface treatment (P=.922) had no significant effect on TBS. Both silanization and sandblasting improved the bonding strength of fiber posts to composite resin core, but there were not any significant differences between these groups and control group.CONCLUSION
There was not any significant difference between two brands of fiber posts that had been used in this study. Although silanization and sandblasting can improve the TBS, there was not any significant differences between surface treatments used. 相似文献17.
M. Eskandari‐Shahraki M. Tavalaee M. R. Deemeh Gh. A. Jelodar M. H. Nasr‐Esfahani 《Andrologia》2013,45(3):204-210
Ubiquitin is an 8.5‐kDa protein that tags outlived proteins for degradation by the proteasome. It also marks defective spermatozoa during epididymal passage and has been proposed as a biomarker of sperm quality. This study evaluates the relationship between sperm ubiquitination, protamine deficiency, semen parameters and fertilisation rate in infertile individuals undergoing the intracytoplasmic sperm insemination (ICSI) procedure. Semen samples from 73 ICSI candidates were collected and analysed according to World Health Organization criteria. A portion of each sample was evaluated for sperm ubiquitination using the sperm ubiquitin tag immunoassay (SUTI) with flow cytometry, and protamine deficiency by chromomycin A3 (CMA3) staining. In addition, the relationship between the fertilisation rate and sperm ubiquitination was calculated in ICSI candidates. The intensity of ubiquitination showed a significant negative correlation with sperm concentration (r = ?0.255, P = 0.032) and a positive correlation with fertilisation rate (r = 0.384, P = 0.013) post‐ICSI. No correlation was observed between protamine deficiency and the percentage of ubiquitination or ubiquitination intensity. The results of this study suggest that sperm ubiquitination prior to capacitation may be considered as a marker of defective spermatozoon. Spermatozoa that undergo proper ubiquitination may have a higher chance for fertilisation, because they are made redundant by the ubiquitin–proteasome pathway in the epididymis compared to hypo‐ubiquitinated spermatozoa. 相似文献
18.
Joseph H. Miller Sarah T. Garber Don E. McCormick Ramin Eskandari Marion L. Walker Elias Rizk R. Shane Tubbs John C. Wellons 《Child's nervous system》2013,29(11):2105-2109
Purpose
Explosive injuries to the pediatric brachial plexus are exceedingly rare and as such are poorly characterized in the medical literature.Methods
Herein, we describe an 8-year-old who was struck in the neck by a piece of shrapnel and suffered multiple vascular injuries in addition to a suspected avulsion of the cervical 5 and 6 ventral rami. The patient had a complete upper brachial plexus palsy and failed to demonstrate any clinical improvement at 6-months follow-up. He was taken to the operating from for a partial ulnar to musculocutaneous nerve neurotization as well as a partial radial to axillary nerve neurotization.Results
The patient’s motor exam improved from a Medical Research Council scale 1 to 4+ for biceps brachii and 0 to 4 deltoid function with greater than 90° of shoulder abduction.Conclusions
This outcome supports complex neurotization techniques as viable treatment options for persistent motor deficits following an upper brachial plexus injury in older, non-infant age, children. 相似文献19.
Sport Sciences for Health - This study was conducted to examine the effect of compound circular exercises on hematological variables and immune system of non-athlete female students. A total of 100... 相似文献
20.
Novel cinnamic acid–tryptamine hybrids as potent butyrylcholinesterase inhibitors: Synthesis,biological evaluation,and docking study
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