钙调素对细胞周期的调节

RC3细胞是一种用真核表达载体1~(CaM)转染NIH 3T3细胞建成的可调钙凋素(Calmodulin,CaM)高表达细胞模型。通过分子杂交及蛋白免疫印迹方法证实在地塞米松(Dexamethasome,DXM)作用下,RC3细胞可高表达CaM。CaM的过表达使G_1期细胞减少,S期细胞增加;CaM拮抗剂三氟拉嗪(trifluoperazine,TFP)则使G_1期细胞增加,S期细胞减少。高表达CaM使细胞分裂指数提高,G_2期细胞减少,有丝分裂前期细胞增加,M中期细胞比例下降。而TFP处理则使分裂指数下降,G_2期细胞增加,M前期细胞减少,M中期细胞增加。实验结果表明CaM在G_1/S、G_2/M和M中期/M后期3个位点上对细胞周期进行调控;通过加速G_1至S期,G_2至M期和M中期至M后期的进程,使细胞倍增时间缩短,促进细胞增殖。本工作表明,RC3细胞作为CaM表达可调细胞模型,是研究细胞周期调控的有力工具。     

牛肝提取物提高仔鸡免疫力的研究

将牛肝提取物注射到第13日龄和第15日龄鸡胚中能显著提高孵出后仔鸡的抗SRBC血清抗体的效价,促进脾和法氏囊淋巴细胞增殖、分化。同时,牛肝提取物与雏鸡法氏囊粗提取液,抗鸡法氏囊病毒抗体均有增强仔鸡抵抗传染性法氏囊病的能力。实验结果表明牛肝提取物中可能含有类似法氏囊素的物质。     

Conditions for the primary culture of eye imaginal discs from Drosophila melanogaster

We have established a primary culture system for Drosophila eye imaginal discs. With this system, we were able to obtain neurite outgrowth from intact eye discs, eye disc fragments, and dissociated eye imaginal disc cells. Immunoreactivity to antibody 24B10 indicates that these extending neurites are photoreceptor axons. Three culture media were tested for their ability to support the survival of and neurite extension from eye disc fragments in vitro at 23°C. These, with supplements, were: five parts of Schneider's Drosophila medium with four parts of basal Eagle's medium (“4+5”); Leibovitz's L-15 medium (L-15); and Shields and Sang's M3 modified medium (MM3). We obtained the best results with MM3 supplemented with 2% fetal bovine serum (FBS). Eye disc fragments survived in this medium for at least 20 days. Pigmentation in the nonphotoreceptor pigment cells in cultures from the prepupa required the presence of 20-hydroxyecdysone (20-HE) (1 μg/ml), whereas neurite outgrowth was seen in the absence of 20-HE. Donor animals had to fall within a range of ages to obtain appropriate eye disc differentiation in vitro. Eye discs from 5-h pupae (P+5) or older commenced ommachrome synthesis in vitro, in a temporal sequence close to that found in vivo, whereas the in vitro synthesis of this pigment was delayed in eye discs from younger flies. Average neurite length was not affected by age among pupae younger than P+5; but neurite outgrowth from P+24 was scarce, probably because by this time photoreceptor axons had already grown in vivo and were severed and unable to regenerate in vitro. Eye discs taken from third instar larvae or white prepupae continued their mitotic activity in vitro. Together with the advance of the morphogenetic furrow at the leading edge of retinal development, this observation is consistent with the evidence that pattern formation continues in vitro. Morphogenetic changes were manifested in cultures. Viability tests with calcein AM and ethidium bromide revealed few dead cells in living cultures. © 1995 John Wiley & Sons, Inc.     

PREDICTING HETEROSIS IN GRAIN YIELD FROM GENETIC DIVERGENCE ANALYSIS IN SUNFLOWER

Geneticdivergenceanalysiswasconductedbasedonperformanceof12quantitativetraitsin85sunflowerinbredlines,tostudyitseffectivenessinpredictingyieldheterosisofthe72hybridsfromthem.Resultsshowedthatlinearregressionmodelfittherelationshipbetweenheterosisofseedoilcontentandgeneticdistance,andquadraticregressionequationtherelationshipbetweengrainyieldheterosisandgeneticdistance,whichcanbeusedinpredictingheterosisfromtheparentperformances.Clusteranalysiswaseffectivetocertainextent,butitsutilizationshouldbelimited.Grainyieldandoilcontentcanbeimprovedsimutaneouslyaccordingtotherelationsbetweengeneticdivergenceandtheheterosisofthesetwotraits.     

辽宁三角洲区域生态经济分区及其功能分析

应用主成分分析和系统聚类分析方法,将辽河三角洲划分为３个生态经济区和８个生态经济小区．通过对反映系统功能的３个表现属性的分析,评价了辽河三角洲农业生态经济系统的功能状况．     

不同施肥杨树主要营养元素内外循环比较研究 Ⅱ．施肥对落叶前后杨树叶片营养元素浓度及贮量的影响

杨树叶片在凋落前将大量有机质输入干、枝、根中,在不同处理中,不施肥输出的比例大于施肥．施Ｐ并不导致杨树对Ｐ的奢侈吸收．施肥可使杨树主要营养元素的外循环通量高于不施肥．不施肥杨树叶片在凋落前Ｐ、Ｋ的输出率比施肥高约１０％．     

甘草属植物化学和药理学研究进展

本文对近年发表的有关甘草属植物化学和药理学研究文献进行了综述,其中包括了得自本属植物的新的黄酮类、三萜类成分。文中以表格形式列出了各类成分的名称、结构、物理常数和植物来源,并对某些成分的生理活性作了归纳。     

银杏叶的研究开发概况

本文对银杏叶的化学、药理、临床和制剂等进行了综述。     

邻单胞菌(Plesiomonas sp.90-1)降解直链烷基苯磺酸钠酶的诱导

在Plesiomonas sp.90-1中,降解直链烷基苯环酸钠(LAS)相关的酶为诱导酶.使用正交多因子法研究了细胞降解LAS酶活诱导的最佳条件为:细胞培养温度30℃,LAS诱导浓度10ppm,酵母膏0.008%,pH8.0,通气.在此条件下,LAS酶活比未经诱导者提高1.4倍.碳源的加入会阻遏LAS降解酶的活力形成.在所试氮源中,以(NH_4)H_2PO_4对LAS降解酶的形成最有利.低浓度的磷酸盐对LAS降解酶活形成无影响,但高浓度的磷酸盐对LAS降解酶活形成不利.利用微量检压技术发现经此条件诱导的细胞耗氧量上升2—3倍.     

医学文眉深浅探讨

本文认为医学文眉是古代文身术与近代医学的结合,是永久性画眉。详细地介绍了医学文眉的材料,方法与适应证。首次将文眉分为追求自然型与润色修饰型。正常求美者和眉型不足者都适合于文眉。鉴于目前除皮肤切除术外,尚无彻底消除文眉痕迹的方法,本文还分析了文眉术后的近期、远期效果,及文眉效果不满意时的补救措施,强调高水平的文眉。讨论了选色深浅、针刺深浅及皮肤深浅与文眉的关系,各深浅的优缺点,并提议文眉时针刺的深度以浅为妙。文中所介绍和讨论的方法。同样适用于文身术。