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91.
Electroporation creates aqueous pathways by short high-voltage pulses resulting in a transient perme- abilization of stratum corneum and an increase in the transdermal delivery rate.However the aqueous pathways will reseal after pulsing,which leads to the rapid drop of transdermal flux.In the present study,the surfactants were added to the donor solution to hinder the shrinkage and resealing of the electropore,and to prolong the lifetime of the aqueous pathways with the consideration that the surfactants could reduce the surface energy of the electropore. These effects of surfactants were demonstrated by the dynamic electrical resistance of the skin and the fluorescent imaging of the local transport regions.Piroxicam(PIX)was transported percutaneously in the presence of surfactants in vitro.Owing to the longer lifetime of aqueous pathways,together with the promotion of PIX availability at the barrier exterior and the improvement in the partition of PIX into the aqueous pathways,the presence of surfactants led to a remarkable increase in the transdermal delivery rate during electroporation and a significant growth of the accumulative transdermal amount of PIX.  相似文献   
92.
目的在大肠杆菌中表达重组人白细胞介素-10(Interleukin-10,IL-10),并检测其生物学活性。方法将IL-10基因重组到质粒pET11c中,转化BL21(DE),提取质粒,经酶切鉴定和测序分析;在25℃用低浓度的IPTG诱导表达,对包涵体IL-10稀释复性;经ELISA检测其含量,MC/9细胞增殖法检测其生物学活性。结果工程菌IL-10/pET11c/BL21诱导表达的目的蛋白以可溶性和包涵体两种形式存在,Westernblot鉴定证实为IL-10蛋白,两种形式的IL-10均具有一定的生物学活性。结论已成功地在大肠杆菌中表达了IL-10,为进一步纯化和制备IL-10的基因工程药物打下了基础。  相似文献   
93.
分析了橡胶制品硫化成型的对象特性,选择了硫化成型过程控制策略,研究了控制算法及其工程应用。研究结果表明,选择仿人智能控制作为硫化成型过程的控制策略时,可实现速度快、精度高的控制,且具有极强的鲁棒性。  相似文献   
94.
根据1964—2015年辽宁省23个气象站点的逐日平均气温、相对湿度及平均风速资料,采用人体舒适度指数法计算人体舒适度指数,在季尺度上分析辽宁省不同等级舒适日数演变情况及典型旅游城市最佳旅游期;运用旋转经验正交函数分解法(REOF),分析人体舒适度指数季尺度空间变化特征,并应用ArcGIS软件进行舒适区域划分。结果表明:①辽宁省多年平均冷不舒适日数呈降低趋势,舒适日数呈增加趋势,热不舒适日数也呈微弱增加趋势;舒适程度夏季>秋季>春季>冬季;②除冬季外5座典型旅游城市均适宜旅游,夏季为最佳旅游期;其中,沈阳、本溪更适宜春季旅游,大连更适宜秋季旅游。③辽宁省四季舒适度变化情况可大致划分为辽西、辽中、辽东三个区域,具体划分情况随季节有相应变化,总体舒适度由辽宁东部向西部逐渐递减。  相似文献   
95.
谢睿 《日用化学品科学》2003,26(3):31-31,33
美白产品始终是夏季护肤品市场竞争的焦点,旁氏推出“日夜美白不停顿”的新概念以应对传统美白产品的挑战,并利用策略发展和广告创意的源动力——“消费者洞察力”概念推出了一套精准的传播策略和创意出色的广告,对消费者产生了很强的吸引力。  相似文献   
96.
The effectiveness of an active shutter-glasses stereoscopic display (SD) and a passive polarised SD was evaluated in a live robot-teleoperation task and a simulated indirect-vision driving task in various terrains. Overall, participants completed their tasks significantly faster with the SDs in three-dimensional (3D) mode than with the SDs in the baseline 2D mode. They also navigated more accurately with the SDs in 3D mode. When the effectiveness of the two types of SDs was examined separately, results showed that the active shutter-glasses SD resulted in faster responses and task completion times than the passive polarised SD, though most of the differences failed to reach statistical significance. Perceived workload when interacting with the two SD systems did not differ significantly between the active versus passive display types or between the 3D and 2D modes of operation; however, participants reported more severe discomfort after interacting with the passive polarised SD.  相似文献   
97.
Providing an easy ingress–egress (I/E) movement remains a challenge for car designers. I/E has been largely studied in kinematics, but not in dynamics. This study proposes: (1) to evaluate and describe the motor torques developed in the lower limbs and lumbar joints during I/E motions and (2) to analyse the influence of the car geometry and subject anthropometry. An experiment was performed to observe 15 subjects of three anthropometrical groups getting in and out of a car mock-up simulating three different vehicle configurations. Motor torques were extracted using an inverse dynamics analysis. Both ingress and egress motions were primarily characterised by large torques. Overall, the taller a subject and the lower the seat of the vehicle were, the larger the peak torques were. Moreover, peak torques were higher for egress than ingress. These results are discussed in regard to the current knowledge on I/E ergonomics.  相似文献   
98.
The paper presents a new approach for recommending suitable learning paths for different learners groups. Selection of the learning path is considered as recommendations to choosing and combining the sequences of learning objects (LOs) according to learners’ preferences. Learning path can be selected by applying artificial intelligence techniques, e.g. a swarm intelligence model. If we modify and/or change some LOs in the learning path, we should rearrange the alignment of new and old LOs and reallocate pheromones to achieve effective learning recommendations. To solve this problem, a new method based on the ant colony optimisation algorithm and adaptation of the solution to the changing optimum is proposed. A simulation process with a dynamic change of learning paths when new LOs are inserted was chosen to verify the method proposed. The paper contributes with the following new developments: (1) an approach of dynamic learning paths selection based on swarm intelligence, and (2) a modified ant colony optimisation algorithm for learning paths selection. The elaborated approach effectively assist learners by helping them to reach most suitable LOs according to their preferences, and tutors – by helping them to monitor, refine, and improve e-learning modules and courses according to the learners’ behaviour.  相似文献   
99.
基于MODIS NDVI数据及标准气象站数据、退耕还林资料,辅以空间统计、叠置分析和趋势分析等方法,研究了金沙江下段植被NDVI时空变化特征及其影响因素,结果表明:从年内来看,金沙江下段植被NDVI变化呈单峰型,3月份为最低值0.55,而9月份为最高值0.75,年际上10年以来植被覆盖总体呈现出增长趋势,且这种增长存在显著的空间异质性;研究区植被覆盖较好,植被NDVI平均值为0.65,海拔3 850m以下植被覆盖随海拔上升而增加,超过3 850m后随海拔升高呈降低趋势;年内植被NDVI受降水量的影响较气温更为明显,对两者均有2个月的滞后期,而年际上植被NDVI则受气温变化的影响较降水量更为突出,且大规模的植被恢复工程对金沙江下段植被覆盖的增加有重要贡献。  相似文献   
100.
Ergonomics/human factors is, above anything else, a systems discipline and profession, applying a systems philosophy and systems approaches. Many things are labelled as system in today's world, and this paper specifies just what attributes and notions define ergonomics/human factors in systems terms. These are obviously a systems focus, but also concern for context, acknowledgement of interactions and complexity, a holistic approach, recognition of emergence and embedding of the professional effort involved within organization system. These six notions are illustrated with examples from a large body of work on rail human factors.  相似文献   
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