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BACKGROUND: Three dimensional skin equivalents are widely used in dermatopharmacological and toxicological studies and as autologous transplants in wound healing. In pharmacology, there is tremendous need for monitoring the response of engineered skin equivalents to external treatment. Transplantation of skin equivalents for wound healing requires careful verification of their quality prior to transplantation. Optical coherence tomography (OCT) is a non-contact, non-destructive imaging technique for living tissues offering the potential to fulfill these needs. This work presents an analysis of OCT for high-resolution monitoring of skin equivalents at different stages during the culture process. METHODS: We developed a high-resolution OCT imaging setup based on a commercially available OCT system. A broadband femtosecond laser light source replaces the original superluminescence diode. Tomograms of living skin equivalents were recorded with an axial resolution of 3 mum and correlated with histology and immunofluorescence images. Comparison with standard low-resolution OCT is presented to emphasize the advantages of high-resolution OCT for this application. RESULTS: OCT is particularly able to distinguish between different layers of skin equivalents including stratum corneum, epidermal and dermal layer as well as the basement membrane zone. The high-resolution OCT scans correlate closely with two key benchmarks, histology and immunofluorescence imaging. CONCLUSIONS: This study clearly demonstrates the benefits of high-resolution OCT for identifying living tissue structure and morphology. Compared with the current gold standard histology, OCT offers non-destructive tissue imaging, enabling high-resolution evaluation of living tissue morphology and structure as it evolves.  相似文献   
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Phenylephrine is widely used as an ophthalmic drug. However, there are only very few reports on allergic contact dermatitis induced by phenylephrine. In addition, little is known on cross reactivity patterns between the sympathomimetics phenylephrine, epinephrine and ephedrine which share a similar chemical structure. We report on a man who developed allergic contact dermatitis to Neosynerphin POS eyedrops containing phenylephrine hydrochloride. Cross reactivity between phenylephrine, epinephrine and ephedrine was studied by patch testing. Patch tests were performed with the European standard, an ophthalmics and preservatives series, Neosynerphin POS eyedrops, phenylephrine hydrochloride 10% aq., epinephrine and ephedrine (both 1.0 % aq.). Test sites were read after 48, 72 and 168 hours according to the recommendations of the ICDRG. Neosynerphin POS and phenylephrine hydrochloride 10 % aq. gave positive reactions, whereas epinephrine and ephedrine tested negative. Although phenylephrine is an epinephrine analog delayed type hypersensitivity to phenylephrine did not result in cross reactivity with chemically related epinephrine and ephedrine.  相似文献   
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异落新妇甙的结构研究   总被引:1,自引:0,他引:1  
李伊庆  易杨华  汤海峰  肖凯 《药学学报》1996,31(10):761-763
从百合科菝葵属植物土茯苓(Smilaxg labra Roxb.)根茎的乙醇提取物中分得一个新的天然化合物(I),命名为异落新妇甙(isoastilbin)。根据元素分析,UV,IR,1H-NMR,13C-NMR,2DNMR及FAB-MS,确定化合物I的结构为5,7,3',5'-四羟基二氢黄酮醇-3-O-α-L-鼠李糖甙。  相似文献   
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Platelet aggregation induced by ADP and collagen was monitored in 25 patients with increased serum levels of triglycerides (7 HLPs type IIb, 14 type IV, 4 type V patients) and compared with a group of 10 normolipidaemic control persons. Platelet aggregation was studied simultaneously in platelet rich plasma (PRP) by both turbidometric and impedance technique and also in whole blood (WB) by the impedance method. Whereas platelet aggregation testing by turbidometry was limited by the optical density of the plasma samples in hypertriglyceridemia, the aggregation process could easily be registered in PRP and WB using the impedance method. Threshold aggregatory concentrations with both agonists were significantly lower for all three groups of HLP.  相似文献   
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Although the concentrations of solutes are very low in water treatment, it cannot be expected that the film-diffusion model predicts breakthrough behavior satisfactorily, for the following reasons: most of the solutes have less favorable isotherms than p-nitrophenol or p-chlorophenol; many solutes are much larger molecules and hence have a much higher internal diffusion resistance than p-nitrophenol or p-chlorophenol; and displacement effects cause a much higher internal resistance than expected from single-solute data. Therefore, internal diffusion resistance has to be incorporated into the film-homogeneous diffusion model. All parameters needed in this model can be obtained from batch reactor tests. Multi-solute systems may be regarded as a single-solute system or a bi-solute system, respectively, if all solutes except one or two are present in very different concentrations; and/or have a comparatively small affinity to activated carbon; and/or have a comparatively small internal diffusion coefficient.  相似文献   
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Dislocation of the proximal tibiofibular joint (PTFJ) in association with a displaced tibial shaft fracture and an intact fibula is an exceedingly rare injury. We present 2 cases of tibia fractures associated with an intact fibula and a PTFJ dislocation. The first case involves a man who sustained a closed spiral fracture of the distal tibial shaft, with an intact fibula, an anterolaterally dislocated PTFJ, and a partial tear of the lateral collateral ligament. The tibia was percutaneously plated, and the PTFJ was reduced and then stabilized with temporary screw fixation. The second case involves a woman who sustained a closed fracture of the tibia in association with a PTFJ dislocation. The tibia was fixed with an intramedullary nail, and the PTFJ was similarly reduced and fixed with a temporary screw. We also provide a brief literature review focusing on classification of PTFJ dislocations, mechanism of injury, associated injuries, and treatment options.  相似文献   
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A proprioceptive deficit is an important determinant of disability in various shoulder disorders, such as instability and osteoarthrosis. In 15 patients with impingement syndrome stage II (Neer 1983), who were treated by arthroscopic subacromial decompression, we measured movement sense by determining threshold levels for the perception of motion of the shoulder. The patients were placed in a specially designed chair allowing continuous passive motion of the shoulder joint, while avoiding cutaneous, auditory and visual stimuli. To assess movement detection thresholds, passive abduction movements of the shoulder were performed at a starting angle of 60°, an amplitude of 10° and an angular velocity of 1.3°/s. Before surgery, all patients had higher threshold levels for the perception of motion in their affected shoulders then in the other side. After decompression, proprioception had improved on the decompressed side, but was unchanged on the other side.  相似文献   
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