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101.
OBJECTIVES: We sought to highlight the clinical, morphologic, and pathogenetic features in patients with a cleft mitral valve (MV). BACKGROUND: Few studies have addressed the morphologic features of cleft MV and the outcome of these patients. The pathogenetic features, including the developmental relation to an atrioventricular (AV) septal defect, remain unclear. METHODS: We reviewed the patients with cleft MV that were diagnosed by echocardiography since 1980. Patients with an AV canal, ventriculo-arterial discordance, and hypoplastic ventricles were excluded. RESULTS: Twenty-two patients were identified at a median age of 0.5 years (range 0 to 10.6). In three patients, no chordal attachments of the cleft to the ventricular septum were seen. Ten patients had significant mitral regurgitation (MR), and three had subaortic obstruction by the cleft. Associated cardiac lesions and extracardiac features were present in 13 and 10 patients, respectively. During the median follow-up period of 1.5 years (range 0 to 11.8), two patients died of extracardiac causes, and one neonate died of severe subaortic obstruction. Surgical repair was performed in 10 patients at a median age of 5.2 years (range 1.3 to 10.6). Multivariate analysis showed no predictors for MV surgery. One patient was re-operated for mitral stenosis associated with aortic valve stenosis. Follow-up echocardiography demonstrated moderate MR in two unoperated patients and moderate MV stenosis in two operated patients. CONCLUSIONS: A cleft of the MV comprises a wide spectrum. Important morphologic differences exist with an AV septal defect, although the two lesions may be pathogenetically related. Surgical repair always seems possible. Long-term echocardiographic follow-up is warranted.  相似文献   
102.
A series of new fluoroquinolone conjugates 8a–g and 9a–f were synthesized via benzotriazole‐mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR‐QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.  相似文献   
103.
[Purpose] To investigate the efficacy of the multi-wave locked system laser therapy on the regeneration of peripheral nerve injuries by evaluating the functional, electrophysiological, and morphological changes of the crushed sciatic nerve in Wistar rats. [Materials and Methods] Sixty male Wistar rats (200–250 g) were randomly assigned to control negative, control positive, or laser groups and subjected to no laser therapy or crushing, to crushing without laser therapy, or crushing followed by multi-wave locked system laser therapy five times/week for four weeks (power=1 W, energy density=10 J/cm2, total energy=100 J), respectively. Functional, electrophysiological, and morphometric analyses were performed before and 7, 15, 21, and 28 days after crushing. The sciatic functional index, compound motor action potential amplitude, motor nerve conduction velocity, and nerve and myelin sheath diameters were measured. [Results] The sciatic functional index value decreased significantly, while the compound motor action potential amplitude, motor nerve conduction velocity, nerve diameter, and myelin sheath diameter increased significantly in the laser group post-treatment compared to the values in the control groups. [Conclusion] Multi-wave locked system laser therapy was effective in accelerating the regeneration of crushed sciatic nerves in Wistar rats.  相似文献   
104.
105.
Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T1 weighted and axial T2 weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies.  相似文献   
106.
Natural use of language involves at least two individuals. Some studies have focused on the interaction between senders in communicative situations and how the knowledge about the speaker can bias language comprehension. However, the mere effect of a face as a social context on language processing remains unknown. In the present study, we used event-related potentials to investigate the semantic and morphosyntactic processing of speech in the presence of a photographic portrait of the speaker. In Experiment 1, we show that the N400, a component related to semantic comprehension, increased its amplitude when processed within this minimal social context compared to a scrambled face control condition. Hence, the semantic neural processing of speech is sensitive to the concomitant perception of a picture of the speaker’s face, even if irrelevant to the content of the sentences. Moreover, a late posterior negativity effect was found to the presentation of the speaker’s face compared to control stimuli. In contrast, in Experiment 2, we found that morphosyntactic processing, as reflected in left anterior negativity and P600 effects, is not notably affected by the presence of the speaker’s portrait. Overall, the present findings suggest that the mere presence of the speaker’s image seems to trigger a minimal communicative context, increasing processing resources for language comprehension at the semantic level.  相似文献   
107.
ABSTRACT

Objective: To assess the prevalence of temporomandibular disorders (TMDs) and posterior crossbite and/or deep bite and any possible association between them.

Methods: One thousand-nineteen adolescents responded to a questionnaire regarding oral habits and TMD symptoms. Afterwards, they were diagnosed according to the Axis I of the DC/TMD and underwent a dental examination. The chi-square test was used for statistical analysis.

Results: A significant association was found between posterior crossbite and some TMD diagnosis, but no association was found between deep bite and TMD, nor between occlusal diagnosis and bruxism. TMDs were more prevalent in girls. There was a significant sex difference (more among females) in the prevalence of painful TMDs.

Conclusion: Posterior crossbite in the adolescent population analyzed may be related to TMDs, in contrary to deep-bite. The presence of posterior crossbite may have different impact on TMD findings between the sexes.  相似文献   
108.
We herein have developed a mild approach for the fabrication of glauconite clay (G)-modified chitosan (CS) nanocomposites by the combination of a simple blending and crosslinking method. The chitosan was modified with ethylenediaminetetraacetic acid (EDTA), glutaraldehyde (GL), sodium dodecyl sulfate (SDS), and cetyltrimethyl ammonium bromide (CTAB). The as-prepared composites were identified using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), nitrogen physical adsorption (BET), atomic absorption spectrophotometry (AA), and thermal gravimetric analysis (TGA). The adsorption activities of the as-prepared materials were assessed for the removal of fluoride ions from aqueous media using a batch technique. Raw glauconite (G), GL-CS/G, SDS-CS/G, EDTA-GL-CS/G, and CTAB-CS/G adsorbents displayed maximum adsorption capacity values of 1.15, 4.31, 4.55, 6.90, and 9.03 mg g−1, respectively. The adsorption results were well described by employing the pseudo-second-order kinetic and Langmuir isotherm models. The estimated thermodynamic constants indicated that the F ion adsorption was a spontaneous, physisorption process. Furthermore, the modified chitosan adsorbents are good candidates for the adsorptive elimination of F ions from aqueous solutions, according to their reusability, high stability, good adsorption capacity, and applicability for actual field water samples.

We herein have developed a mild approach for the fabrication of glauconite clay (G)-modified chitosan (CS) nanocomposites by the combination of a simple blending and crosslinking method.  相似文献   
109.
110.
ObjectivesTo compare the effect of various degrees of decalcification after orthodontic treatment (white spot lesions) on orthodontists'', general dentists'', and laypersons'' ratings of smile esthetics.Materials and MethodsEight photographs representing incrementally altered tooth decalcification lesions of maxillary anterior teeth ranging from mild to severe were shown randomly to the study participants. Photographs were rated by a matched sample of orthodontists (N = 42), general dentists (N = 52), and laypeople (N = 58). A visual analogue scale (VAS) was used to assess perceptions of smile esthetics.ResultsThe three groups of raters could distinguish between different decalcification levels. Raters gave more negative scores as the decalcification level increased.ConclusionsThe three groups of raters were able to distinguish between various degrees of decalcification lesions. General dentists were the most critical of all groups when rating decalcification lesions.  相似文献   
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