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91.
Cyanoacrylate has been used in several fields of different surgical specialties as an adhesive for closure of gingival flaps and in mucous and cutaneous lacerations. One of its advantages is that it has an excellent immunological response. In view of aesthetic needs, cyanoacrylate has been applied with satisfactory results, when compared with sutures. It presents better coaptation of edges of cutaneous and mucosal lesions, smaller residual scars, and biocompatibility. However, it is limited to areas of little tissue tension. This work attempts to provide a literature review with the aim of revealing the advantages of using tissue adhesives, especially cyanoacrylates, in wound coaptation in comparison with conventional methods.  相似文献   
92.
OBJECTIVE:To determine the effects of a formal auditory training program on the behavioral, electrophysiological and subjective aspects of auditory function in individuals with bilateral high-frequency hearing loss.METHOD:A prospective study of seven individuals aged 46 to 57 years with symmetric, moderate high-frequency hearing loss ranging from 3 to 8 kHz was conducted. Evaluations of auditory processing (sound location, verbal and non-verbal sequential memory tests, the speech-in-noise test, the staggered spondaic word test, synthetic sentence identification with competitive ipsilateral and contralateral competitive messages, random gap detection and the standard duration test), auditory brainstem response and long-latency potentials and the administration of the Abbreviated Profile of Hearing Aid Benefit questionnaire were performed in a sound booth before and immediately after formal auditory training.RESULTS:All of the participants demonstrated abnormal pre-training long-latency characteristics (abnormal latency or absence of the P3 component) and these abnormal characteristics were maintained in six of the seven individuals at the post-training evaluation. No significant differences were found between ears in the quantitative analysis of auditory brainstem responses or long-latency potentials. However, the subjects demonstrated improvements on all behavioral tests. For the questionnaire, the difference on the background noise subscale achieved statistical significance.CONCLUSION:Auditory training in adults with high-frequency hearing loss led to improvements in figure-background hearing skills for verbal sounds, temporal ordination and resolution, and communication in noisy environments. Electrophysiological changes were also observed because, after the training, some long latency components that were absent pre-training were observed during the re-evaluation.  相似文献   
93.
The literature related to the effects of elevated plasma ammonia levels on brain energy metabolism is abundant, but heterogeneous in terms of the conclusions. Thus, some studies claim that ammonia has a direct, inhibitory effect on energy metabolism whereas others find no such correlation. In this review, we discuss both recent and older literature related to this controversial topic. We find that it has been consistently reported that hepatic encephalopathy and concomitant hyperammonemia lead to reduced cerebral oxygen consumption. However, this may not be directly linked to an effect of ammonia but related to the fact that hepatic encephalopathy is always associated with reduced brain activity, a condition clearly characterized by a decreased CMRO2. Whether this may be related to changes in GABAergic function remains to be elucidated.  相似文献   
94.
The proper disposal of electrical and electronic waste is currently a concern of researchers and environmental managers not only because of the large volume of such waste generated, but also because of the heavy metals and toxic substances it contains. This study analyzed printed circuit boards (PCBs) from discarded computers to determine their metal content and characterized them as solid waste and fuel. The analysis showed that PCBs consist of approximately 26% metal, made up mainly of copper, lead, aluminum, iron and tin, as well as other heavy metals such as cadmium and nickel. Comparison with the results of other studies indicated that the concentration of precious metals (gold and silver) has declined over time. Analysis of the leachate revealed high concentrations of cadmium and lead, giving the residue the characteristics of hazardous waste. After milling the PCBs, we found that larger amounts of metal were concentrated in smaller fractions, while the lightest fraction, obtained by density separation, had a gross calorific value of approximately 11 MJ/kg, although with a high ash content. Milling followed by density separation proved potentially useful for recovery of metals and energy-rich fractions.  相似文献   
95.

Background  

Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population.  相似文献   
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Abnormalities in craniofacial morphology are associated with Eustachian tube dysfunction and otitis media with effusion (OME).Aim: to evaluate the relationship between facial pattern and craniofacial growth direction, and OME in children with enlarged tonsils and adenoids (ETA).Methods: Clinical prospective survey in 79 children (41 male and 38 female), ranging from 4 to 10 years of age, with tonsil and adenoid enlargement (Brodsky's grades III and IV). Forty children presented with OME (study group) and 39 did not (control group). Cephalometric analysis was used to determine the facial pattern.Results: There was no correlation observed between facial pattern and OME (c 2 = 0.25 p = 0.88). Facial Axis was larger in the OME group (F(1.75) = 3.68 p = 0.05) and the Lower Anterior Facial height was smaller (F(1. 75) = 3.99 p = 0.05) in children with otitis media with effusion.Conclusions: There was no correlation between OME and facial pattern in children with ETA although a more horizontal facial growth direction, and a smaller lower anterior facial height was observed consistently among subjects in this group. This suggests that abnormal positioning of the eustachian tube influences the development of OME in children with ETA.  相似文献   
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The assessment of D-dimer concentration has become essential step during diagnostic algorithm of venous thromboembolism (VTE). This test characterizes high sensitivity but limited specificity. Negative D-dimer with high probability excludes VTE. The aim of this study was to assess the percentage of patients treated in Department of Internal Medicine, Endocrinology and Haemostatic Disorders, Medical University of Gdańisk, who in spite of clinical signs of VTE showed normal D-dimer level. Between 2000 and 2004 in our department 57 cases with recent deep vein thrombosis (DVT) were diagnosed, in 2 cases with co-existence of pulmonary embolism (PE). The D-dimer concentration was assessed in patients' plasma with the use of immunoturbidometry. Between 57 cases with VTE, 7 patients (12%) showed normal D-dimer level (<500 microg/ml). This group consisted of 4 men and 3 women, aged from 40 to 82 years (the mean age of 58 years). In all 7 cases DVT was diagnosed, in 2 patients with concomitent PE. The final diagnosis was confirmed by compression ultrasonography and pulmonary scintigraphy. Our analysis underlines the observation that occurrence of VTE and negative d-dimer concentration is possible and may probably be related to methodological limitations. However, the lack of increase of D-dimer could also be caused by fibrinolysis alteration.  相似文献   
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