大蒜对环磷酰胺诱发的小鼠骨髓细胞微核和姊妹染色单体交换的保护作用

本文以小鼠骨髓嗜多染红细胞的微核率和小鼠骨髓细胞姊妹染色单体交换(SCE)率两个指标,测定大蒜匀浆滤液(GJ)对环磷酰胺(CP)诱变作用的影响。结果表明,用GJ灌胃处理小鼠能降低CP(30mg/kg)诱发的微核率,差异极显著(P<0.01)。用GJ处理小鼠,除了CP高剂量(30mg/kg)外,CP中和低剂量(3mg/kg和0.3mg/kg)所诱发的SCE率均受到抑制,有显著性差异(P<0.05)。表明大蒜有较强的抗诱变能力,具修复染色体损伤和DNA错误复制的功能。     

刺激隐神经中C类纤维诱发的小脑浦肯野细胞简单...

Simple spike of cerebellar Purkinje cells (PC-SS) was recorded with microelectrode. In the NCCVF (normalized cross-covariance function) histogram, spontaneous PC-SS does not show obvious peak. When the saphenous nerve is stimulated at lower intensities, which elicits the A-fiber input only, the discharge response (A-CED) consists of an early component with a latency of 16.7 +/- 0.9 ms and a late component with a latency of 270.8 +/- 12.8 ms. After A-fibers are blocked selectively by polarizing current, the stimulation at a suprathreshold strength for C-fiber evokes a characteristic response (C-CED) with a latency of 142.4 +/- 4.3 ms. However, the C-CED can not be evoked by the inputs of A- and C-fiber simultaneously. In NPSDF histogram, the spontaneous activities of PC-SS can be divided into two groups, the high and the low peak group. The high peak group (n = 15) has a peak energy value of 15.7 +/- 4.7 x 10(-3) and peak frequency of 4.07 +/- 1.69 Hz. A-fiber input causes an increase of the peak value, while C-fiber input causes a decrease. The low peak group (n = 16) has a peak energy value 8.4 +/- 1.4 x 10(-3) and peak frequency of 3.67 +/- 2.90 Hz. Both A-fiber and C-fiber inputs cause an increase of the peak value, but the effect of A-fiber input was more prominent. The results show that the pure C-fiber input can reach the cerebellar PC and elicit characteristic simple spike response.     

植物细胞在离体培养条件下的决定问题

“决定”(Determination)这一术语来自动物胚胎发育生物学,意指胚胎某一区域的组织或细胞只能向某一特定方向分化的发育状态。决定与否以及决定的程度必须用离体培养或异位移植的方法来测定。“决定”作为发育生物学上的一种现象,同样存在于高等植物中,如茎生长点的成花决定和     

强化后期氮素营养对提高水稻结实率及改善米质的作用

加强后期氮素营养能提高杂交水稻碳氨同化能力和结实率,稻米的蛋白质和八种必需氨基酸含量、谷类蛋白的赖氨酸和苏氨酸也有提高。     

多胺在离体培养的植物组织形态建成中的作用

本文概述了多胺在原生质体培养,外植体发生愈伤组织、不定根、不定芽、体细胞胚胎、花芽和小鳞茎等过程中的作用,并简述了它的作用机制。     

桑树叶肉原生质体培养再生植株

近年来,木本植物原生质作诱导再生植株的研究越来越受到国内外学者关注。但在林木树种中,迄今成功的种类仍然不多,在文