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41.
抗马拉硫磷淡色库蚊不同基因型的自然内禀增长率及其对抗性演化的影响 总被引:13,自引:0,他引:13
本文涉及淡色库蚊(Culex pipiens pallens)抗马拉硫磷纯合子(RR)、杂合子(RS)和敏感纯合子(SS)的自然内禀增长率及其对马拉硫磷抗性演化的影响。RR、RS和SS的内禀增长率分别为0.1118、0.1171和0.1339。RR和RS基因型在无杀虫剂时呈现出繁殖不利性,RR和RS的相对适合度分别是SS的0.65和0.68。 影响淡色库蚊对马拉硫磷进化的某些因子在计算机上进行了模拟。模拟的因子包括R等位基因的起始频率(P_o)、所用马拉硫磷的剂量和迁入率(m)。模拟结果表明(I)不用药时R等位基因衰减是由于RR和RS基因型的繁殖不利性;(2)在起始种群N_o=200,P_o=0.1,使用杀死全部SS和RS的剂量(8ppm)处理,使R等位基因为有效隐性,并且m≥0.15时可阻止马拉硫磷抗性的发生。 相似文献
42.
W. John Albery Anthony E.G. Cass Bernard P. Mangold Zhi Xin Shu 《Biosensors & bioelectronics》1990,5(5)
It is shown that an inhibited enzyme electrode, using cytochrome oxidase, will respond to H2S, HCN and azide ion. For all three inhibitors the kinetics of the inhibition and recovery processes have been analysed using the theoretical model presented previously (Albery et al., 1990a). Rearrangement of the differential equation describing inhibition and the development of the necessary software has enabled us to obtain values of the concentration of inhibitor in a matter of seconds after exposure of the sensor. The sensor will measure concentrations of H2S down to 1 ppm in the gas phase and concentrations of HCN and azide ion down to 0·4 μmol dm−3 in the solution 相似文献
43.
本文记述中国新纪录正鳃金龟属Malaisius Arrow(1941)及4个新种——云南松正鳃金龟Malaisius pinae,介正鳃金龟M.intermedius,背黑正鳃金龟M.melanodiscus及闽正鳃金龟M.fujianensls。结合4新种之特征,重新描述了本属属征,指出正鳃金龟属与歪鳃金龟属Cyphochilus Waterheuse近缘。 相似文献
44.
蜜蜂总科化石新种(昆虫纲:膜翅目) 总被引:1,自引:0,他引:1
本文记述了膜翅目熊蜂科、木蜂科和蜜蜂科3属3新种,其中熊蜂科熊蜂属1种:鲁熊蜂Bombus luianus sp. nov., 木蜂科木蜂属1种:硅藻木蜂Xylacopa diatoma sp. nov. 和蜜蜂科蜜蜂属1种:长胫蜜蜂Apis longitibia sp. nov.。所有模式标本均采自山东山旺中新统硅藻土页岩中,现保存在山东省博物馆。 相似文献
45.
电针、吗啡镇痛和耐受时某些脑区线粒体结合钙的变化 总被引:1,自引:0,他引:1
采用 Tb~(3+)荧光探针和离子选择电极研究了电针和吗啡镇痛及镇痛耐受时,动物不同脑区游离 Ca~(2+)和线粒体膜结合 Ca~(2+)的变化。实验结果表明,电针和吗啡都有较强的镇痛作用,与此同时,导水管周围灰质和下丘脑的线粒体膜结合 Ca~(2+)升高。脑室内预注钌红,则能降低这两个脑区的线粒体膜结合 Ca~(2+)和痛阈。另一方面,在电针或吗啡耐受时,两脑区的游离 Ca~(2+)浓度增加,线粒体膜结合 Ca~(2+)降低。结果提示,神经细胞质膜内外 Ca~(2+)的移动可能在电针和吗啡镇痛中起某种调节作用。 相似文献
46.
47.
We have previously established an in vitro sensitization (IVS) procedure with which lymphocytes from tumor-bearing mice could be expanded and sensitized to acquire antitumor reactivity capable of mediating the regression of established pulmonary metastases from the weakly immunogenic MCA 105 murine sarcoma. Culture conditions required for the optimal generation of therapeutic effector cells were evaluated in the current study. Generation of effector cells by IVS required stimulation by intact tumor cells. Tumor cells killed by heat or disrupted by sonication were ineffective, but the antigenicity of tumor cells was not affected by gamma-irradiation. Long term established tumor cell lines could also serve as antigenic stimulator cells albeit with lower efficiency than fresh tumor cells. IL-2 was essential for cellular proliferation during IVS. The concentration of 1000 U/ml of IL-2 also induced nonspecific lymphokine-activated killer (LAK) activity. However, cytotoxic cells were generated during IVS in response to a broad range of IL-2 concentrations. At low IL-2 concentrations (2 to 10 U/ml), IVS cells were generated which displayed little or no LAK activity, had a greater therapeutic efficacy than those generated with high concentrations of IL-2 (100 to 1000 U/ml). Despite having high LAK activity, IVS cells, from cultures where IL-2 was added 3 or more days after initiation, had no therapeutic effect. Thus, the generation of therapeutic cells occurred independently of LAK cell production. Adoptive immunotherapy with IVS cells from MCA 105 tumor-bearing mice demonstrated cross-reactivity with the immunologically distinct MCA 106 but not the nonimmunogenic MCA 102 tumor. In contrast, IVS cells from MCA 106 tumor-bearing mice exhibited specific in vivo reactivity. In vitro cytotoxicity analyses revealed that IVS cells from MCA 105 and MCA 106 tumor-bearing mice were able to lyse both MCA 105 and MCA 106 target cells, but the reactivity toward inoculating tumors was highest. Considering previous findings that the MCA 105 and MCA 106 sarcomas possessed distinct tumor-specific transplantation Ag, the cross-reactivity observed in this study suggests that the immune response during progressive tumor growth may be different from that elicited in response to active immunization. 相似文献
48.
The uterine acetylcholinesterase and total cholinesterase (acetylcholinesterase plus butyrylcholinesterase) activities in normal and fenchlorphos treated blue fox vixens were determined during various reproductive states. AChE and Total-ChE of non-medicated vixens in oestrus were about one half of those in anoestrus. In pregnant uteri (luteal phase) the activities were 25 % and 30% compared to anoestrus. In vixens given 100 mg/kg fenchlorphos for 3 weeks during anoestrus, the remaining activity of AChE in uterus were in average 37%. Pregnant and non-pregnant vixens in the luteal phase medicated prior to mating and during time of implantation, displayed AChE activities which were only moderabely reduced (remaining activities 83% and 72% compared to medicated animals in anoestrus: remaining activity 37%). Plasma ChE-activity increased during pregnancy in the controls while enzyme activity was strongly reduced in animals given 100 mg/kg fenchlorphos daily through the whole pregnancy. It was concluded that the previous reported embryotoxic effect of fenchlorphos in the blue fox did not seem to be directed towards the moderate inhibition of the uterine cholinesterases. 相似文献
49.
50.
采用一种简便而快速的方法分离了盐泽螺旋藻的藻胆体。藻胆体的最大吸收波长位于618 nm,室温下荧光反射峰位于677~678 nm。利用7~15%SDS—聚丙烯酸胺梯度凝胶板状电泳,可分出三条有色多肽,其中藻蓝蛋白的α亚单位与别藻蓝蛋白的α亚单位几乎重叠,不易区分;另有分子量为117,99,53,49,27,24.5和14kD的七条无色多肽。117和 99kD多肽可能联结藻胆体和类囊体,并作为末端能量受体,而14kD多肽多为“核”亚结构的组分,其余的可能为“棒”亚结构内和“核”“棒”亚结构间的联结蛋白。 相似文献