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21.
Niu Yuan Wang Fang Liu Le Zhang Guoliang Qi Bo Liu Xinhai Zhao Hongliang Huang Zhiwei Fan Song Zhang Linqing 《Journal of Plant Growth Regulation》2023,42(1):154-167
Journal of Plant Growth Regulation - 1,2,4-trichlorobenzene (1,2,4-TCB) pollution in fields has become a potential threat to rice growth, yet little is known about the different response of many... 相似文献
22.
为提高蚕豆的抗病性、抗虫性和着荚性,人们试图将其与野生近缘种进行种间杂交,但因杂交幼胚早期败育,至今未获成功。解决杂交幼胚的发育问题已成杂交成功的关键。作者以自交授粉15天的幼胚珠为材料,确立了由幼胚珠离体培养经继代直接成苗的方法,获得可正常开花结实的完整植珠。以蚕豆为母本与5个近缘种进行了种间杂交,对杂交20天的杂交幼胚珠进行了离体培养,经愈伤组织再分化形成试管苗。为克服蚕豆与近缘种杂交幼胚的败育进行了探索。 相似文献
23.
脏器微血管对荧光素钠通透性的实验方法 总被引:4,自引:1,他引:3
大鼠颈动脉注射1%FlNa,荧光显微镜下活体观察肠系膜微血管血流状态及FlNa的渗出情况,并在不同时间点经股动脉采血,测定血浆内FlNa浓度随时间的变化,利用组织匀浆测定不同脏器中FlNa的分布,再辅以冰冻切片进行观察。活体观察发现,FlNa注入体内后,经微血管迅速向周围组织渗出,最后汇集于淋巴管,血浆及组织匀浆FlNa浓度的测定表明,FlNa浓度随时间的变化呈指数衰减,各脏器FlNa的分布极不相同。冰冻切片也显示了同样的分布差别。这些结果表明,我们所建立的方法可直观、定量地反映FlNa在微血管的通透情况。 相似文献
24.
25.
从皖南尖吻蝮蛇(Agkistrodonacutus)毒液中经DEAE-Sepharose和SephacrylS-200两步凝胶柱层析首次纯化出一种中分子量出血毒素(简称AaHⅣ).经SDS-PAGE和等电聚焦凝胶电泳测定其分子量为44kD,等电点为pH5.0.从500mg粗毒中可获得20mgAaHⅣ纯品.AaHⅣ有较强的出血活性,最小出血剂量(MHD)为0.4μg. 相似文献
26.
27.
应用异羟基洋地黄毒甙元(Digoxigenin)标记的RNA探针,检测了人和黑猩猩血清及肝脏中丁型肝炎病毒核酸,并与~(32)P标记同一探针做了比较。结果表明,异羟基洋地黄毒甙元标记的RNA探针的杂交效果与同位索探针一致(同源cDNA0.2pg),可用于人和动物血清及肝脏标本内HDV核酸的检测。 相似文献
28.
球形芽孢杆菌Ts—1毒蛋白的分离纯化 总被引:3,自引:2,他引:1
Bacillus sphaericus strain Ts-1 is highly insecticidal to larvae of the mosquito. It's insecticidal component is toxic proteins. The toxin was extracted from spore-crystal complexes by disruption in a Sonicator Cell Disruptor Model W-220F followed by treatment with 0.05 mol/L NaOH. Fraction recovered from chromatography of the spore-crystal complexes on column of Sephadex G-200 were assayed against mosquito larvae and the toxic fractions from gel chromatography were subjected to SDS-PAGE. The toxic proteins in B. sphaericus Ts-1 spore-crystal complex migrated in position corresponding to 42kD and 43kD. Bioassay of the two purified proteins prepared by PAGE indicated that they were all toxic to mosquito larvae. Toxic protein was further purified by DEAE-cellulose chromatography. The toxic protein with a molecular weight of 42kD was obtained. 相似文献
29.
W. F. Li J. Ji G. Wang H. Y. Wang B. L. Niu T. L. Josine 《Russian Journal of Genetics》2011,47(9):1039-1046
Many natural proteins have been developed into drugs and produced for direct application. Identifying improved hosts to achieve
high-level heterologous protein production is a challenge in the study of heterologous protein expression in recombinant yeast.
In this study, a novel high-throughput assay to screen such overproducing Saccharomyces cerevisiae strains was systematically developed. The protocol designed was based on screening host strain derivatives with increased
superoxide dismutase dependent resistance to oxidative stress. Yeast cells transformed with recombinant plasmid carrying SOD1 gene as a reporter responded exquisitely to oxidative stress induced by elevated concentrations of paraquat. Improved yeast
strains resulting from screening clones subjected to genome shuffling through selective pressure argue for a more effective
screening system compared with traditonal selection. Moreover, this approach can be employed in general biochemical analysis
without utilization of flow cytometry or well plate reader. Therefore, it is expected that the high-throughput assay would
make superior strains producing heterologous proteins. 相似文献
30.
Research has revealed that most chlorophyllous explants/plants in vitro have the ability to grow photoautotrophically (without
sugar in the culture medium), and that the low or negative net photosynthetic rate of plants in vitro is not due to poor photosynthetic
ability, but to the low CO2 concentration in the air-tight culture vessel during the photoperiod. Moreover, numerous studies have been conducted on improving
the in vitro environment and investigating its effects on growth and development of cultures/plantlets on nearly 50 species
since the concept of photoautotrophic micropropagation was developed more than two decades ago. These studies indicate that
the photoautotrophic growth in vitro of many plant species can be significantly promoted by increasing the CO2 concentration and light intensity in the vessel, by decreasing the relative humidity in the vessel, and by using a fibrous
or porous supporting material with high air porosity instead of gelling agents such as agar. This paper reviews the development
and characteristics of photoautotrophic micropropagation systems and the effects of environmental conditions on the growth
and development of the plantlets. The commercial applications and the perspective of photoautotrophic micropropagation systems
are discussed. 相似文献