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71.
Finn AV  Saeed O  Virmani R 《Circulation research》2012,110(9):e64; author reply e65-e64; author reply e66
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72.
BackgroundThe treatment for mandibular condyle fractures remains controversial. Conservative management (CM) and open reduction/internal fixation (ORIF) are both used, but the evidence to support superiority of one method over the other has not been assessed.MethodsWe performed a meta-analysis of studies comparing CM versus ORIF in patients with condyle fractures. The primary outcome was post-treatment function; we looked at the status of the post-treatment occlusion, mouth opening, protrusion, facial height, pain and the presence of postoperative ankylosis. Furthermore, in studies evaluating ORIF, adverse effects such as facial nerve weakness and scarring, were also recorded.ResultsTwenty (20) studies enrolling 1596 patients were eligible. These included four randomized controlled trials (RCTs) and 16 non-randomized case series. Only 1186 of these patients were analyzed by the studies; the reasons for exclusion were rarely clarified. All four RCTs were prospective but the majority (69%) of the remaining studies were retrospective. The inclusion criteria were described in all four RCTs; however, this was not the case in half of the remaining studies (44%). Only four (20%) studies were blinded. Across all included studies, we recorded great variation between treatment protocols, follow-up periods, and outcomes measured. This precluded any quantitative synthesis. In nine studies (45%) the superiority of ORIF over CM reached statistical significance. The incidence of facial nerve weakness following ORIF averaged 6% and it was temporary for the majority of the patients. The identified RCTs were small (160 patients) and suffered from a number of methodological shortcomings. All of them reached statistically significant conclusions favoring ORIF over CM.ConclusionThe current meta-analysis suggests that ORIF for condylar fractures may be as good or better than CM. The morbidity associated with the operation is low. However, the available evidence is of poor quality and not strong enough to change clinical practice.  相似文献   
73.
This study compared the push‐out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root‐end filling materials in root‐end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single‐rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, root‐end cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root‐end cavities were prepared using Er,Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm‐thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two‐way anova . Root‐end filling materials showed significantly higher bond strength in root‐end cavities prepared using ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root‐end cavities were comparable and higher in ultrasonically prepared cavities.  相似文献   
74.
Here we compare the management and survival outcomes of chronic myeloid leukemia (CML) patients who had early or late imatinib mesylate (IM) therapy. The cytogenetic and molecular responses of 189 CML patients were analyzed. Of this group, 121 patients were classified as the early chronic phase (ECP) group and started IM within 12 months of diagnosis. The other 68 patients were classified as the late chronic phase (LCP) group who had been treated with interferon (IFN)-alpha-2 and crossed over to IM more than 12 months after diagnosis. The overall rates of complete cytogenetic response (CCyR) and major molecular response (MMR) at last follow-up were 83.6 and 78.1% in the ECP and LCP groups, respectively. The CCyR rates were 89.3 (for ECP patients) versus 73.5% (for LCP patients; p < 0.0001). At last follow-up, 82.4% ECP and 64.2% LCP patients had achieved an MMR (p < 0.0001). No significant differences were noted between the two groups with regard to survival outcomes. Our experience reveals that IM is an effective rescue therapy in most CML LCP patients who are intolerant or in whom IFN-alpha therapy fails. Such therapeutic options should be considered in LCP patients, particularly in countries where IM may not be available.  相似文献   
75.
This paper chronicles a 2-year-old girl who presented with acute leukemia/lymphoma syndrome of the T cell immunophenotype. At this time, the cytogenetic analysis of her bone marrow cells showed a reciprocal translocation between the short arm of chromosome 12 and the long arm of chromosome 13, t(12;13)(p13;q14). The immunophenotyping of bone marrow blast cells by flow cytometry revealed a population of cells positive for CD56, CD117, CD45, partial CD33, partial HLA-DR, CD13, CD7, CD2 and CD5. Therefore, a diagnosis of acute leukemia with a mixed T cell/myeloid phenotype was made. The patient had a poor response to classic T cell acute lymphocytic leukemia/lymphoma therapy; thus, her treatment was changed to a myeloid leukemia protocol, which produced a good response. She underwent a successful cord blood transplantation from an unrelated HLA partially matched donor. The coexistence of these two phenotypes prompts questions about the existence of clonal instability, which might influence the choice of therapy. The rarity of the t(12;13)(p13;q14) and the coexistence of T cell/myeloid markers suggest a nonrandom association. To the best of our knowledge, this is the first reported case in which a cell clone bearing a t(12;13)(p13;q14) translocation in a mixed T cell/myeloid lesion was detected.  相似文献   
76.
BackgroundDeep brain stimulation (DBS) has emerged as a potential therapeutic strategy in the treatment of neurological disorders including epilepsy. However, the cellular mechanism responsible for the effects of DBS remains largely undefined. Therefore, using electrophysiological approach, we aimed to determine the antiepileptic effects and restorative potential of low frequency stimulation (LFS) on amygdala kindling-induced changes in electrophysiological properties of rat hippocampal CA1 pyramidal neurons.MethodsAnimals were kindled by electrical stimulation of amygdala in a rapid kindling manner (12 times per day). In one group of animals, immediately after termination of daily 12 rapid kindling stimulations, the kindling site was subjected to 4 packages of LFS at intervals of 5 min (each package contained 200 monophasic square-wave pulses, 0.1 ms pulse duration at 1 Hz). Whole cell patch clamp recording under current clamp conditions was performed on visually identified pyramidal neurons in hippocampal slice preparations obtained from amygdala-kindled rats and the rats receiving LFS.ResultsKindling of the right basolateral amygdala profoundly affected spontaneous firing behavior and repetitive discharge characteristics of pyramidal neuronal electrophysiological properties. Application of LFS at the kindling site almost completely prevented the development of epilepsy and the disruptive effects of kindling on neuronal electrical activity through restoration of the normal electrophysiological characteristics.ConclusionsThe results of this study implied that application of LFS during kindling acquisition prevents the kindling induced changes in functional electrical properties of CA1 pyramidal neurons, suggesting that this action may be involved in the antiepileptogenic mechanism of LFS.  相似文献   
77.
To investigate the role of sex steroids of the seminal fluid on sperm quality, the relationships between sex steroids and milt quality parameters (sperm motility and sperm production) were investigated in the Persian sturgeon. The seminal fluid levels of 17α,20β,21-trihydroxy-4-pregnen-3-one (20βs), and 11-ketotestosterone (11-KT) had positive relationships with sperm motility characteristics (percentage and duration of motility) and sperm density. Also, no relationships were found between other sex steroids including: Testosterone (T), progesterone (P), 17α-hydroxyprogesterone (OHP), and milt quality parameters. The good correlation of 20βs and 11-KT of the seminal fluid with sperm motility and sperm density suggests that these steroids may be important hormones involving in final maturation of the Persian sturgeon spermatozoa.  相似文献   
78.
A 23-year-old man presented with a history of fibrous ankylosis of the left temporomandibular joint (TMJ), scarring and shortening of the left temporalis muscle secondary to transection, and surgically-induced neuropathic pain after previous decompression of the temporal bone. There was evident hollowing of the left temporal fossa, and mouth opening was limited to 5 mm. The aims of the operation were to treat the ankylosis, improve cosmesis, and reduce his medication. His left TMJ was reconstructed with a custom-made alloplastic joint, and a simultaneous custom-made cranioplasty. At follow-up after 2 years he was free of pain and taking no drugs. He had no obvious cranial deformity, and his mouth opening had increased to 35 mm. To our knowledge this is the first reported case of simultaneous custom-made cranioplasty and reconstruction of the TMJ.  相似文献   
79.
International Journal of Paediatric Dentistry 2013; 23: 56–63 Objective. To compare clinical and radiographic outcomes of pulpotomy treatment using calcium‐enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) in carious‐exposed vital immature permanent first molars. Design. Fifty‐one immature molars with clinical carious exposure with symptomatic/asymptomatic pulpitis met the inclusion criteria and randomly assigned to one of the treatment groups (CEM [26 teeth; 59 roots], MTA [25 teeth; 59 roots]). After performing pulpotomy and covering the radicular pulps with the biomaterials, all teeth were permanently restored. Blinded clinical and radiographic evaluations were performed at 6 and 12 months after operation for signs of success or failure. Radiographs were evaluated for complete/partial apical closure. The data were analysed using chi‐square test and generalized estimating equation (GEE) model. Results. There was no significant difference at the baseline between the two experimental groups. All available cases (49 teeth) showed pulp survival and signs of continuous root development after 12 months. Overall, complete apical closure (apexogenesis) occurred in 76.8% and 73.8% of radiographically interpreted roots in CEM cement and MTA groups, respectively. There was no statistical difference in terms of radiographic outcomes between two groups. Conclusions. Calcium‐enriched mixture cement and MTA showed similar performance in pulpotomy of immature caries‐exposed permanent molars.  相似文献   
80.
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