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ABSTRACT: Reconstruction of columella presents certain difficulties and includes reconstruction of the cartilaginous strut and the overlying skin to obtain good results. We conducted a retrospective clinical review of 38 patients presenting with congenital and acquired columellar defects. Anatomic characteristics to be considered were defined and a classification method is proposed to more fully describe columellar defects. The columellar defects of the patients were classified into three groups as follows: type I, skin defect of columella and absence of medial crura of lower lateral cartilage; type II, type II + partial absence of caudal part of septal cartilage; and type III, complex defect of columella accompanying with the other nasal subunit defects. The patients chosen in this study were designed to describe a common approach for the choice of the reconstruction method that provides excellent aesthetic result while minimizing the extent of the surgery and maximizing patient acceptance.  相似文献   
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World Journal of Surgery - Traditional chemotherapy agents adversely affect wound healing and need to be held prior to or after surgery. Immune checkpoint inhibitors (ICIs) and targeted agents are...  相似文献   
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Several studies have demonstrated that L-carnitine exhibits neuroprotective effects on injured sciatic nerve of rats with diabetes mellitus. It is hypothesized that L-carnitine exhibits neuro-protective effects on injured sciatic nerve of rats. Rat sciatic nerve was crush injured by a forceps and exhibited degenerative changes. After intragastric administration of 50 and 100 mg/kg L-carnitine for 30 days, axon area, myelin sheath area, axon diameter, myelin sheath diameter, and numerical density of the myelinated axons of injured sciatic nerve were similar to normal, and the function of injured sciatic nerve also improved signiifcantly. These ifndings suggest that L-carnitine exhibits neuroprotective effects on sciatic nerve crush injury in rats.  相似文献   
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Pharmaceutical Chemistry Journal - In this study, seven new 3(2H)-pyridazinone derivatives expected to show cytotoxic activity in liver and colon cancer cell lines were synthesized. Their...  相似文献   
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Covalent-organic polymer networks (COPNs) have been used as catalyst supports due to their stable and favorable structure. Herein, a simple synthetic route was applied to generate Au@COPN-1 hybrids via in situ reduction of gold ions with no additional reducing agent. Synthesized novel COPN-1 was mixed with different concentrations of HAuCl4 which resulted in Au@COPN-1 with varying sizes of Au nanoparticles in a controlled manner. The microstructural and morphological features of COPN-1 and Au@COPN-1 were characterized in detail using FT-IR, C-NMR, elemental analysis, UV-Vis, XRD, TEM, BET, and TGA. It is noteworthy that the red-shifted LSPR peaks of Au nanoparticles produced with increasing concentrations of HAuCl4 indicated an increase in the particle size of the Au nanoparticles as justified by TEM images. The optimum catalytic activity of Au@COPN-1 was obtained when 4.6 × 10−3 mM HAuCl4 was used, which led to the complete reduction of 4-nitrophenol within 16 minutes with excellent recyclability for more than 5 catalytic cycles, giving yields over 94%. Moreover, the non-aggregation of nanoparticles in the reused catalyst further confirmed the stability of the prepared catalysts. Consequently, these results indicated that in situ synthesis of AuNPs inside the COPN-1 matrix produces a promising catalyst platform for the reduction of aromatic nitro compounds, for example, for the degradation of one of the most common persistent organic pollutants 4-nitrophenol, as shown here. In addition, the Au@COPN-1 hybrid system showed good biocompatibility at appropriate doses confirmed by a dynamic real-time cell analysis system which can be used in various medical applications, such as drug delivery, in the future.

A facile synthetic route was applied to generate Au@COPN-1 hybrids via in situ reduction of Au3+ with no additional reducing agent. Au@COPN-1 is a promising catalyst platform and good biocompatibility confirmed by dynamic real-time cell analysis.  相似文献   
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Myoelectric signals were detected from the tibialis anterior muscle of 5 subjects with a quadrifilar needle electrode while the subjects generated isometric forces that increased linearly with time (10% of maximal voluntary contraction/s) up to maximal voluntary level. Motor unit firing rates were studied as a function of force throughout the full range of muscle force output. The relationship between force and firing rate was found to contain three distinct regions. At recruitment and near maximal force levels, firing rates increased more rapidly with force than in the intermediate region. Furthermore, in the regions with rapid increases, the rate of change of firing rate was correlated to the recruitment threshold, with higher recruitment threshold motor units displaying greater rates of change. In the intermediate region, all motor units had similar rates of change of firing rate. A weak positive correlation was found between initial firing rate and recruitment threshold. Firing rates of motor units at any instant were found to be ordered according to the recruitment order: at any given time in the contraction motor units with lower recruitment thresholds had higher firing rates than units with higher recruitment thresholds. Firing rates of all motor units were observed to converge to the same value at maximal forces. Mechanisms underlying motor unit recruitment and firing rate modulation are discussed in the context of a conceptual model. © 1996 John Wiley & Sons, Inc.  相似文献   
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