与正常材料不同的是，当加热时，该材料不是膨胀，而是收缩，表现出负的热膨胀现象。
Instead of expanding when heated — as is normally the case — the material contracts, a phenomenon known as negative thermal expansion.
结论：山参果汁总皂苷具有负性肌力和负性频率作用，即抑制心肌收缩和舒张功能，减慢心率、降低动脉血压。
Conclusion WGFS has the effects of negative frequency named restraining cardiac muscle contraction and stretch function, and reducing rhythum of the heart and blood pressure.
心肌梗死大鼠心肌细胞增殖程度与心脏收缩功能呈正性相关，与舒张功能呈负性相关。
Myocyte proliferation is positively correlated with heart systolic function, and negatively correlated with heart diastolic function in chronic heart failure.
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