采用四点是弯曲加载装置对原代培养的大鼠颅盖骨细胞施加周期性的拉伸刺激，并设计了应变呈梯度增加的加载方式，使成骨细胞受到的拉伸应变为500～1500μδ，每隔2h增加500μδ，以考察成骨细胞对变化的力学环境的响应。结果表明，在500μδ下拉伸2～6h促进了成骨细胞的增殖、碱性磷酸酶活力增强和胞外钙基质沉积。对细胞施加应变呈梯度增加的拉伸刺激，则发现当应变从有利于细胞的生长分化水平(500μδ)变化为不利于细胞生长分化的水平(1000μδ，1500μδ)后，细胞的增殖指数、碱性磷酸酶活力和胞外钙基质分泌量都迅速降低，以适应新的力学环境。说明成骨细胞能够分辨不同的应变水平，并相应地调节自身的生理功能，从而表现出对变化的力学环境的适应。

信号肽在引导外源蛋白分泌过程中具有重要作用，本文从信号肽疏水性结构、构建分泌型载体以及分泌增强子、定位信号等几个方面介绍了信号肽对外源蛋白分泌效率的影响，在大量生产以酵母为表达宿主的治疗性蛋白方面具有广泛的应用前景。

骨组织的生长发育受到力学因素的调控. 对大鼠颅盖骨中分离出的成骨细胞施加周期性拉伸刺激, 结果表明500 微应变的加载明显促进了细胞的增殖, 而1000 和1500 微应变的拉伸抑制了细胞的增殖. 各应变水平的拉伸增加了细胞与基底间的黏附力和细胞的铺展面积. 用荧光探针Fluo-3/AM 测定拉伸对成骨细胞胞内Ca2+浓度的影响, 发现在500 微应变下拉伸5 min 后成骨细胞胞内Ca2+浓度比对照组有明显增加. 用三七总皂苷阻断胞内Ca2+通道后, 成骨细胞对应变的响应仍表现出胞内Ca2+浓度的升高; 但与未加三七总皂苷的加载组相比, 胞内Ca2+浓度响应应变后的升高由原来的92.9%的增加降低到28.6%的增加. 说明在成骨细胞响应周期性拉伸应变的过程中胞内Ca2+ 浓度的升高既有胞外钙内流的参与, 也有胞内钙库的释放作用, 其中胞外钙通过跨膜通道的内流起主要作用.

Objective: To develop an on-line system for the measurement of blood viscosity and hematocrit. The dynamic changes of the macrovascular blood volumes, microvascular blood volumes and the total blood volume were observed by means of calculating from the testing result. Methods: Applying traditional viscosity measurement principle and specif ic wavelength optic density measurement method, an on-line system for the measurement of blood viscosity and hematocrit was developed, and the APD multifunctional board and the testing circuit were designed by ourselves. The system was validated by experiments both in vitro and in vivo. Therapeutic effects of hypertonic saline dextran solution (HSD) and Lactatic Ringerps solution at the early stage after burn-blast combined injury were compared by this method. Results: The results showed that the system has attained the goal of the design. The changes of the blood viscosity and hematocrit could be detected effectively and continuously. The changes of macrovascular, microvascular and total blood volume could be calculated approximately. Conclusions: The system and the method can continuously on-line test the blood viscosity and hematocrit, and reveal the change and distribution of blood volumes more accurately and clearly in the therapy process by estimating changes of the macrovascular, microvascular and total blood volumes, respectively. It has conf irmed that HSD treatment could increase blood pressure and attenuate tissue edema by signif icantly increasing total blood volume, improving macrocirculatory and microcirculatory blood volumes. This study suggested that it could be desirable to develop an experiment technique based on the method mentioned above.

目的探讨机械拉伸应变对人肺上皮细胞增殖及其膜受体——整联蛋白α5、β1再分布的调控作用。方法建立体外周期性拉伸装置，应用流式细胞术测定细胞的增殖活性，激光共聚焦显微镜分析整联蛋白α5、β1再分布。结果在应变为15%，频率为20次/min、40次/min的拉伸刺激下，24h后，细胞的增殖活性指数明显降低，H727细胞的DHA合成受到显著抑制。在40次/min的拉伸频率下，整联蛋白α5、β1的分布发生重组并向基底层转移，形成局部粘附连接。结论整联蛋白α5、β1可能在肺上皮细胞感应机械应力过程中起了重要的作用。