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BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up.  相似文献   
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Whereas decubitus ulcer in the back or hip region is a common entity in plegic or elderly patients, the occurrence in the lateral shoulder region is seldom seen. However, resulting from continuous lateral decubitus positioning or limited compliance by the patient, pressure sores may occur in almost any region of the body, but predominately, they arise in acral zones with underlying bone prominences. The deltoid area is such an anatomically critical region, especially if the underlying deltoid muscle is paralyzed. The transposition of a pedicled deltoid flap, slightly modified as a hatchet flap, is described for cover of a decubitus ulcer in the deltoid region in a paraplegic male. Although utilization of the deltoid flap as a free flap is an established procedure for selected indications [Russell et al. (1985) Extremity reconstruction using the free deltoid flap. Plast Reconstr Surg 76:586–595, Serafin D (1996) The deltoid flap. In: Serafin D (ed) Atlas of microsurgical composite tissue transplantation, chapter 19. Saunders, Philadelphia, PA, pp 153–159, Wang et al. (2003) The free deltoid flap: microscopic anatomy studies and clinical application to oral cavity reconstruction. Plast Reconstr Surg 112:404–411], transposition as a pedicled flap, to the best of our knowledge, has not been previously described in the available literature.  相似文献   
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Nestin is an intermediate filament protein typical for neural precursor cells that is down-regulated in the post-natal rodent brain. Re-expression of nestin has been observed in reactive astrocytes after injury. In this study, organotypic slice cultures from rat cortex were examined for expression of nestin and glial fibrillary acidic protein between 2 and 8 weeks in culture. Immunoreactivity for nestin and glial fibrillary acidic protein was seen in astrocytes which persisted throughout the observation period. Immunofluorescence double labeling showed widespread co-localization of nestin and glial fibrillary acidic protein. Image analysis revealed that levels of nestin-immunoreactivity plateaued after 5 weeks in culture. By comparison nestin immunoreactivity was absent from glial cells of the cortex in mature rats. These immunohistochemical findings of a persistent expression of nestin in glial cells of organotypic slice culture of the rat cortex indicate a different time course of glial maturation in vitro. This difference could be related to the altered trophic stimulation in vitro; differences in neuronal maturation, activity or survival; slow degeneration of the vasculature; or intrinsic properties of astrocytes.  相似文献   
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