花粉提取物对带瘤小鼠胸腺T细胞数量变动的影响

本文报道用~3H-TdR掺入法研究花粉提取物对带瘤小鼠胸腺T细胞在有丝分裂原作用下增殖反应的影响。并用酵母多糖混合玫瑰花形成试验,观察其胸腺细胞中T、Tr和T_μ细胞数量变动的影响。实验结果表明:带瘤小鼠胸腺细胞的增殖反应均低于正常小鼠,经花粉提取物灌胃后,其胸腺细胞的增殖反应均有不同程度提高;T、Tr及T_μ细胞数均比对照组升高。说明花粉提取物具有促进免疫细胞活性的作用。     

用混合细菌89-01固定化细胞去除合成洗涤剂废水中LAS

本文报道一组能去除LAS的混合细菌89-01,以及该混合细菌固定化细胞在去除模拟合成洗涤剂废水中LAS时的某些性质。最适温度37℃,最适pH值为3,该固定化细胞热稳定性基本良好。用其固定化细胞柱连续处理模拟废水,当进水中LAS为50mg/(?)时,出水中LAS的去除率可达60—80%。     

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.     

刺激隐神经中C类纤维诱发的小脑浦肯野细胞简单锋电位反应

用玻璃微电极记录了猫小脑浦肯野细胞的简单锋电位(PC-SS)。在标准化互协方差函数图中,PC-SS自发放电无明显波峰;弱刺激隐神经只引起A类纤维传入时,PC-SS出现A类诱发放电反应(A-CED),它包括潜伏期为16.7±0.9ms的早反应和270.8±12.8ms的晚反应。用极化电流选择性阻滞A类纤维传导后,强刺激只引起C类纤维单独传入时,出现潜伏期为142.4±4.3ms的C类诱发反应(C-CED)。强刺激同时引起A类和C类纤维传入时,只出现A-CED而不出现C-CED。按标准化功率谱密度函数分析,PC-SS自发放电可分为两种类型。一类为高峰型,最大能量峰值平均为15.7±4.7×10~(-3),峰频为4.07±1.67Hz;刺激A类纤维使峰值增大,而刺激C类纤维却使峰值减小。另一类为低峰型,峰值为8.4±1.4×10~(-3),峰频为3.67±2.90Hz。刺激A类和C类纤维均使峰值增大,前者增大更多,但峰频均无显著性变化。上述结果表明,C类纤维传入可以到达小脑浦肯野细胞,引起特异的PC-SS放电反应。     

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