钙拮抗剂TMB-8抑制BHQ,NE和KCl引起的培养乳牛基底动脉单个平滑肌细胞内游离钙的升高

用ＡＲＣＭＭＩＣ阳离子测定系统，测量单个细胞内游离钙浓度（［Ｃａ２＋］ｉ），研究８（Ｎ，Ｎ二乙胺）ｎ辛基３，４，５三甲氧基苯甲酸酯（ＴＭＢ８）对培养乳牛基底动脉平滑肌［Ｃａ２＋］ｉ的作用。在细胞外钙浓度为１３ｍｍｏｌ·Ｌ－１时，ＴＭＢ８（３０μｍｏｌ·Ｌ－１）可明显抑制ＢＨＱ，ＮＥ及ＫＣｌ引起［Ｃａ２＋］ｉ的升高。在细胞外钙为零＋ＥＧＴＡ０１ｍｍｏｌ·Ｌ－１时，ＴＭＢ８（１０，３０及１００μｍｏｌ·Ｌ－１）可浓度依赖性地降低静息［Ｃａ２＋］ｉ，ＴＭＢ８（３０μｍｏｌ·Ｌ－１）可几乎完全阻断ＢＨＱ及ＮＥ引起［Ｃａ２＋］ｉ的增加。研究表明ＴＭＢ８降低培养乳牛基底动脉平滑肌［Ｃａ２＋］ｉ的机制，主要是抑制肌浆网Ｃａ２＋的释放，或增加肌浆网对Ｃａ２＋的摄入，并由此间接地抑制细胞外钙的内流。     

Work in progress: the application of temporal filtering techniques to hybrid subtraction in digital subtraction angiography

Temporal filtering methods were applied to iodine signal-to-noise ratio (SNR) restoration in intravenous hybrid subtraction digital subtraction angiography (DSA). For equal detected exposure rates hybrid subtraction had approximately 35% of the SNR of temporal subtraction. When matched filtering was applied to a DSA run, the filtered result had approximately two times higher SNR than the peak contrast image in the run. Thus, when matched filtering techniques were applied to the hybrid image sequence, the resultant SNR increased to about 70% of that of temporal subtraction. With an additional factor-of-two increase in exposure rate for the hybrid run, SNR parity with temporal subtraction could be achieved. This compared with a factor-of-nine increase in exposure that would be required if no filtering were performed. Experimental hybrid matched filter results, generated with intravenous canine DSA studies, supported the predictions in SNR performance.