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121.
Astrocyte proliferation is strictly controlled during development and in the adult nervous system. In this study, we examined the role of sulfated hyaluronan (SHya) in the proliferation and differentiation of normal human astrocytes (NHAs). Cells were cultured with different concentrations of SHya for 7 days, and the number of viable cells and the presence of neural cell-specific genes were determined to assess their proliferation and development, respectively. With SHya, cell proliferation increased nonsignificantly. Furthermore, remarkable enhancing action by SHya on connexin-26, -32, and -43 gene expressions were observed during the culture of NHAs. It has been suggested that a fraction of NHAs have neural precursor activity that gives rise to astrocytes themselves, oligodendrocytes, and neurons. Our results clearly demonstrated that the expression of specific genes for neural precursor cells, astrocytes, neurons, and oligodendrocytes was significantly increased to 50 mug/mL in SHya-treated cultures when compared with that of the control culture. These findings suggest that SHya plays an important role in the proliferation and differentiation of NHAs and in the production of a novel material for tissue engineering.  相似文献   
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Background The repair of an alar nasal defect is a frequent challenge for dermatologic surgeons for reasons of the high rate of non‐melanoma cancers in the area. Objective Our aim was to describe the use of an east–west cheek‐based flap (horizontal advancement flap) to repair a surgical defect on the nose ala. Methods Benefits and limits of this surgical procedure are evaluated. Result The resulting S‐shaped scar was well‐camouflaged among the natural skin lines (melolabial fold and melonasal junction). No architectural distortion of the nose resulted from the procedure. Conclusion In selected patients with small‐to‐medium‐size defects of the nasal ala, the horizontal advancement flap is a simple, reliable and aesthetic reconstruction option.  相似文献   
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Standard of care for patients with chronic hepatitis C is pegylated interferon (pegIFN) combined with ribavirin (Rbv). It results in persistent viral eradication and prevents the progression of liver disease and the associated complications in about 50% of treated patients. Currently, two PegIFNs are available that differ significantly in terms of pharmacokinetic and pharmacodynamic profiles as a consequence of different pegylation chemistries. While the registration trials of the two therapeutic regimens demonstrated the superiority of each PegIFN vs the native IFN α2b, the superiority of one regimen over the other in terms of treatment efficacy remains unknown. Retrospective cohort studies and randomized prospective head-to-head trials have attempted to resolve the considerable controversy over this issue and support evidence-based treatment decisions.  相似文献   
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Crossover learning may aid rehabilitation in patients with neurological disorders. Ideomotor apraxia (IMA) is a common sequela of left-brain damage that comprises a deficit in the ability to perform gestures to verbal commands or by imitation. This study elucidated whether crossover learning occurred in two post-stroke IMA patients without motor paralysis after gesture training approximately 2 months after stroke onset. We quantitatively analysed the therapeutic intervention history and investigated whether revised action occurred during gesture production. Treatment intervention was to examine how to influence improvement and generalisation of the ability to produce the gesture. This study used an alternating treatments single-subject design, and the intervention method was errorless learning. Results indicated crossover learning in both patients. Qualitative analysis indicated that revised action occurred during the gesture-production process in one patient and that there were two types of post-revised action gestures: correct and incorrect gestures. We also discovered that even when a comparably short time had elapsed since stroke onset, generalisation was difficult. Information transfer between the left and right hemispheres of the brain via commissural fibres is important in crossover learning. In conclusion, improvements in gesture-production skill should be made with reference to the left cerebral hemisphere disconnection hypothesis.  相似文献   
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