怎样预防乳房下垂

SNO content was measured using the Saville-Griess assay as described with minor modifications (Feechan et al., 2005). In the Saville-Griess assay, S-NO bonds were broken by mercuric chloride, and the released NO reacted with sulfanilamide. The resulting diazonium salt is coupled with the aromatic amine N-(1-naphthyl)-ethylenediamine to form an intensely colored azo dye that can be measured at 540 nm (Feechan et al., 2005; King et al., 2005). Briefly, fine powder of plant tissues from liquid nitrogen was lysed in 600 mL of extraction buffer (50 mM Tris-HCl, pH 8.0, and 150 mM NaCl) containing 1 mM protease inhibitor phenylmethanesulfonyl fluoride (PMSF) and incubated on ice for 20 min. After centrifugation at 10,000 rpm for 15 min at 4 C, 160 mL of supernatant clear cell lysate was incubated with the same volume of 1% sulfanilamide and 0.1% N-(1-naphthyl)-ethylenediamine with or without the addition of 3.75 mM HgCl2 for 20 min in the dark. Then, SNO content was measured photometrically at 540 nm using 96-well plates with Tecan Infinite M200 (Tecan Group). The SNO content was calculated according to the absorption at 540 nm and a GSNO concentration standard curve (Feechan et al., 2005). SNO含量用Saville-Griess法检测: SNO被HgCl2破坏,释放的NO与磺胺反应,生成的重氮盐与芳香胺(N-(1-萘基)-乙二胺)结合生成偶氮染料,可以被540nm波长测定。 即:液氮研磨粉末后,溶解于600mL含有1mM蛋白酶抑制剂PMSF的提取缓冲液(50mM Tris-HCl,pH8.0,150mM NaCl)中,冰上孵育20min。4℃,10000rpm离心15min后,160mL 上清加入同样体积的1%磺胺和0.1%N-(1-萘基)-乙二胺中,加入3.75mM HgCl2,黑暗条件下处理20min。不含HgCl2为对照。 SNO含量通过测定540nm处吸光度获得。