Action mechanisms of a new erythrocyte-derived depressing factor

To investigate the action mechanisms of a new erythrocyte-derived depressing factor (EDDF), the focus is placed on the effect of EDDF on both cytosolic and nuclear free calcium (Ca²⁺) transportation in vascular smooth muscle cell (VSMC), as well as the apoptosis and cell cycle of VSMC of rats. EDDF has been extracted from human erythrocytes. The changes of Ca²⁺ levels in cytoplasm ([Ca²⁺]_i) and nucleus ([Ca²⁺]_n) have been observed using a laser scanning confocal microscope together with fluo-3/AM as a calcium indicator. Flow cytometric technique was used to study the effect of EDDF on cell cycle and apoptosis of VSMC. [Ca²⁺], and [Ca²⁺]_n were significantly decreased through several different pathways: ( i ) it reduced the Ca²⁺ influx by blocking L-type voltage-dependent calcium channel (L-VDC) and R-type voltage-dependent calcium channel (R-VDC); (ii) it inhibited the Ca²⁺ release from inositol 1, 4, 5-trisphosphate (IP₃) sensitive calcium store; and (iii) activated Ca²⁺-ATPase of sarcoplasmic reticulum (SR) and promoted the transportation of Ca²⁺ from cytoplasm to SR. However, EDDF seemed to have little inhibitory effect on the Ca²⁺ release from ryonodine sensitive calcium pool. It was also found that EDDF (10⁻⁴ g/mL) significantly decreased the proportion of S phase of human umbilical vein (HUV) and inhibited the proliferation of VSMC induced by angiotensin II (Angll, 10⁻⁵ mol/L). The apopotosis did not occur when VSMC was cultured under normal condition. While VSMC apoptosis was induced by Angll (10⁻⁵ mol/L) and EDDF (10⁻⁴ g/mL) seemed to have little effect on it. The inhibitory effect of EDDF on the elevation of [Ca²⁺]_i and [Ca²⁺]_n of VSMC might play an essential role in its action mechanisms and the ways it affects the Ca²⁺ handling of VSMC demonstrate that EDDF was different from other endogenous blood pressure regulators and some known antihypertensive drugs. EDDF could inhibit the proliferation of VSMC, which indicated that it might be beneficial to the prevention and treatment of hypertension and arteriosclerosis.     

雌激素剂量对动情周期大白鼠子宫及卵巢中明胶酶-A活性的影响

本实验采用ＳＤ大白鼠为实验材料,研究了雌激素与动情周期子宫和卵巢中明胶酶－Ａ活性变化的关系,结果显示：Ｅ２对动情后期子宫及卵巢中激活形式明胶酶－Ａ活性均有促进作用,明胶酶Ａ的活性变化与Ｅ２剂量变化呈正比关系,但卵巢中明胶酶－Ａ活性明显低于子宫。Ｐ４（孕酮）对处于动情前期大鼠子宫中明胶酶－Ａ活性没有显作用,在对动情前期卵巢的作用中虽能看出明显胶酶－Ａ活性随Ｐ４剂量的增加而逐渐下降的趋势,但没有显     

论旅游商品开发与新疆旅游业发展

本在阐明旅游商品与旅游产品、旅游购物品的区别和旅游商品开发在旅游业发展中的重要作用的基础上,分析了我区旅游商品开发的现状及存在问题,提出了新疆旅游商品开发的原则与对策。     

雪鸡与环境的相互关系

在驯养雪鸡中，从最小空间需要量，饲科与食性、光照与繁殖、气温与调控等六个方面，阐述了环境对雪鸡的行为反应，提出了人工养殖雪鸡的综合性措施，并为开发雪鸡自然资源提出了理论和技术依据。     

查利的天使

砰!砰! 我睡觉从来都不会睡得很死,听到敲门声,我一下坐起来,扣好衬衫扣子,折叠好毯子,和枕垫一起放在长沙发椅后面.如果是你,你也不想让你的客户发现你在办公室里睡觉的,那是有违职业准则的,在私家侦探行业里更是大忌,即使(特别是)……     

奇妙的非晶态金属

在日常生活中,人们所接触的材料不外乎两类,即晶态材料和非晶态材料。形象地说,如果材料中的原子排列像被检阅的士兵方阵那样有序,该材料就是晶态材料;如果原子排列像集市的人群那样杂乱无章,那么这种材料就是非晶态材料。在我们接触的物质中,食盐、钻石等都属于晶态材料,而木材、纺     

人工驯养雪鸡的产卵性能及电机孵卵试验

人工驯养雪鸡的产卵性能及电机孵卵试验王正己，哈孜，马英，未来，海罗拉（动物科学系乌鲁木齐县阿克苏）ＤｏｍｅｓｔｉｃＴｅｔｒｏｇａｌｌｕｓ＇ｓＬａｙｉｎｇＰｅｒｆｏｒｍａｎｃｅａｎｄＥｘｐｅｒｉｍｅｎｔｏｆＭａｃｈｉｎｅＨａｔｃｈ￥ＷａｎｇＺｈｅｎｊｉ...     

民族传统体育在西部高校开设的个案分析

民族体育是民族文化走向世界的一个重要的载体。本文对陕西师范大学和喀什师范学院的各150名非体育专业大学生民族体育方面知识的认识进行了调查,分析目前高校开设民族传统体育的现状。结果表明:高校"公体"虽开设民族传统体育项目,但相对于现有丰富的民族体育资源来说,开设的非常局限;高校民、汉学生对民族传统体育有较高的兴趣爱好;在民族体育的相互交融方面,对本地区民族传统体育的了解要高于对异地民族传统体育的了解。     

Th-rich zircon from peralka line A-type granite： Mineralogical features and petrological implications

Zircon is one of the most common accessory minerals in igneous rocks, especially in granites. It exists through the crystallization and evolution of grantic magma be-cause of stable physicochemical properties. Trace element abundances (e.g. Hf, Th, U, Y) in zircon are very sensitive to the crystallization environments[1]. Therefore, zircon plays an important role in the granite research. However, although A-type granites are given more and more regards by the geologists owing to their charac…