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71.
Hooshmand T Rostami G Behroozibakhsh M Fatemi M Keshvad A van Noort R 《Journal of dentistry》2012,40(2):139-145
Objectives
To evaluate the effect of HF acid etching and silane treatment on the interfacial fracture toughness of a self-adhesive and two conventional resin-based cements bonded to a lithium disilicate glass ceramic.Methods
Lithium disilicate glass ceramic discs were prepared with two different surface preparations consisting of gritblasted with aluminium oxide, and gritblasted and etched with hydrofluoric acid. Ceramic surfaces with a chevron shaped circular hole were treated by an optimized silane treatment followed by an unfilled resin and then three different resin cements (Variolink II, Panavia F2, and Multilink Sprint). Specimens were kept in distilled water at 37 °C for 24 h and then subjected to thermocycling. The interfacial fracture toughness was measured and mode of failures was also examined. Data were analysed using analysis of variance followed by T-test analysis.Results
No statistically significant difference in the mean fracture toughness values between the gritblasted and gritblasted and etched surfaces for Variolink II resin cement was found (P > 0.05). For the gritblasted ceramic surfaces, no significant difference in the mean fracture toughness values between Panavia F2 and Variolink II was observed (P > 0.05). For the gritblasted and etched ceramic surfaces, a significantly higher fracture toughness for Panavia F2 than the other cements was found (P < 0.05).Conclusions
The interfacial fracture toughness for the lithium disilicate glass ceramic system was affected by the surface treatment and the type of luting agent. Dual-cured resin cements demonstrated a better bonding efficacy to the lithium disilicate glass ceramic compared to the self-adhesive resin cement.Clinical significance
The lithium disilicate glass ceramic surfaces should be gritblasted and etched to get the best bond when used with Panavia F2 and Multilink Sprint resin cements, whereas for the Variolink II only gritblasting is required. The best bond overall is achieved with Panavia F2. 相似文献72.
Mohseni Rashin Hamidieh Amir Ali Shoae-Hassani Alireza Ghahvechi-Akbari Masood Majma Anahita Mohammadi Mahmoud Nikougoftar Mahin Shervin-Badv Reza Ai Jafar Montazerlotfelahi Hadi Ashrafi Mahmoud Reza 《Neurological sciences》2022,43(1):399-410
Neurological Sciences - Spinal muscular atrophy (SMA), an autosomal recessive neurodegenerative disorder of alpha motor neurons of spinal cord associated with progressive muscle weakness and... 相似文献
73.
Leily Mohajerzadeh Alireza Mirshemirani Mohsen Rouzrokh Naser Sadeghian Ahmad Khaleghnejad-Tabari Alireza Mahdavi Sareh Poorhasan 《Iranian journal of pediatrics.》2016,26(1)
Background:
Hypospadias is one of the most common congenital genital anomalies in males that necessitates to be operated early in infancy (when 6 to 9 months old). On the other hand, hypospadias is a challenging field of pediatric urology with multiple reconstruction techniques. A perfect hypospadias repair is supposed to return urethral continuity with sufficient caliber, eradicate phallus curvature, and supply an acceptable appearance with low complications.Objectives:
This study aimed to evaluate the outcomes of using onlay island flap technique in the repair of hypospadias with shallow urethral plate.Patients and Methods:
In this prospective study within June 2012 to December 2013, we performed onlay island flap procedure to repair hypospadias with shallow urethral plate measuring less than 6 millimeter. This technique was selected for all types of hypospadiasis except subcoronal type. Nesbit’s dorsal plication procedure was established for chordee. In cases with very small glans, urethroplasty was performed without glansplasty.Results:
Twenty three patients with mean age of 30 (range 10 - 60) months underwent onlay island flap repair; all had a shallow urethral plate < 6 mm, 3 had a very small glans, and 18 had chordee. Meatus was located in distal shaft in 5 cases, mid shaft in 8, proximal in 6 and penoscrotal type in 4 patients. Chordee was corrected with Nesbit’s dorsal plication in 16 cases. Complications were: meatal stenosis in 2 cases and urethrocutaneous fistula in 2 patients, all of which were repaired surgically. Mean follow up time was 13 (3 - 20) months. All cases that had glansplasty have excellent esthetic appearance.Conclusions:
This technique offers acceptable results regarding meatal stenosis, urethrocutaneous fistula and esthetic outcome. 相似文献74.
75.
Komaki A Shahidi S Lashgari R Haghparast A Malakouti SM Noorbakhsh SM 《Neuroscience letters》2007,426(3):181-186
In this study we investigated the hypothesis whether P2-related differences tested in a visual priming paradigm are associated with theta phase-locking. We recorded the EEG from 31 electrodes and calculated phase-locking index and total power differences for frequencies between 2 and 20 Hz. ERPs (event-related potentials) were analyzed for P1, N1 and P2 components. P2 showed strongest task-related amplitude differences between congruent and incongruent targets. A source analyses was performed for the P2 component using sLoreta that revealed local generators of the P2 in parieto-occipital regions. Phase-locking analyses showed specific effects in the theta range (4-6 Hz) appearing in time windows at around the P2 component. We draw the conclusion that phase-locked theta reflect top-down regulation processes mediating information between memory systems and is in part involved in the modulation of the P2 component. 相似文献
76.
Mönkkönen KS Aflatoonian R Lee KF Yeung WS Tsao SW Laitinen JT Tuckerman EM Li TC Fazeli A 《Human reproduction (Oxford, England)》2007,22(5):1224-1230
BACKGROUND: Heterotrimeric G proteins take part in membrane-mediated cell signalling and have a role in hormonal regulation. This study clarifies the expression and localization of the G protein subunit G alpha(i2) in the human endometrium and Fallopian tube and changes in G alpha(i2) expression in human endometrium during the menstrual cycle. METHODS: The expression of G alpha(i2) was identified by Polymerase chain reaction (PCR), and localization confirmed by immunostaining. Cyclic changes in G alpha(i2) expression during the menstrual cycle were evaluated by quantitative real-time PCR. RESULTS: We found G alpha(i2) to be expressed in human endometrium, Fallopian tube tissue and in primary cultures of Fallopian tube epithelial cells. Our studies revealed enriched localization of G alpha(i2) in Fallopian tube cilia and in endometrial glands. We showed that G alpha(i2) expression in human endometrium changes significantly during the menstrual cycle, with a higher level in the secretory versus proliferative and menstrual phases (P < 0.05). CONCLUSIONS: G alpha(i2) is specifically localized in human Fallopian tube epithelial cells, particularly in the cilia, and is likely to have a cilia-specific role in reproduction. Significantly variable expression of G alpha(i2) during the menstrual cycle suggests G alpha(i2) might be under hormonal regulation in the female reproductive tract in vivo. 相似文献
77.
Visual context shapes human perception, yet our understanding of this phenomenon in terms of synaptic circuitry is still rudimentary. Our in vitro experiments with avian tectum reveal two distinct GABAergic pathways that mediate the spatiotemporal tectal interaction of retinal inputs. One pathway mediates postsynaptic lateral inhibition. The other pathway interacts with the synaptic depression of retinotectal synapses. Simulations of an experimentally constrained model including the two pathways reproduce the observed avian tectum wide-field neuron's sensitivity to small and moving stimuli, while being insensitive to whole-field motion. 相似文献
78.
79.
Synthesis,evaluation, and molecular docking studies of aryl urea‐triazole‐based derivatives as anti‐urease agents 下载免费PDF全文
Setareh Moghimi Fereshteh Goli‐Garmroodi Maryam Allahyari‐Devin Hedieh Pilali Malihe Hassanzadeh Shabnam Mahernia Mohammad Mahdavi Loghman Firoozpour Massoud Amanlou Alireza Foroumadi 《Archiv der Pharmazie》2018,351(7)
80.
Aaron Yarlas Martha Bayliss Joseph C. Cappelleri Stephen Maher Andrew G. Bushmakin Lea Ann Chen Alireza Manuchehri Paul Healey 《Quality of life research》2018,27(2):273-290