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61.
以玉米种子为试验材料,采用砂培法研究了水杨酸(SA)对铅(Pb2+)胁迫下玉米种子的萌发、叶绿素含量、MDA含量、POD活性、等方面的影响。结果表明:低浓度的SA≤80mg/L时,能促进铅胁迫下玉米幼苗的生长,表现为玉米种子的发芽率增大,幼苗根长的增加,叶绿素含量增大,MDA的含量降低,POD活性升高,等。当SA浓度为60mg/L～80mg/L,Pb2+≤1mg/L时,SA对Pb2+的解毒效应最明显,当SA浓度为100mg/L,Pb2+为8mg/L时,SA与Pb2+协同迫害幼苗的生长。 相似文献
62.
He XL Yin HL Wu J Zhang K Liu Y Yuan T Rao HL Li L Yang G Zhang XM 《Journal of Zhejiang University. Science. B》2011,12(1):32-39
Radiation therapy has been widely applied in cancer treatment. However, it often causes thrombocytopenia (deficiency of white
blood cells) as an adverse effect. Recombinant human interleukin-6 (rhIL-6) has been found to be a very effective way against
this thrombocytopenia, but IL-6 has low stability in blood, which reduces its efficacy. To increases the stability and half-life
of rhIL-6, it was modified by polyethylene glycol (PEG). The pharmacokinetics and the tissue distribution of PEG-rhIL-6 labeled
with 125I were examined after subcutaneous injection in rats. The pharmacokinetic pattern of PEG-rhIL-6 was defined with linear-kinetics,
and we fitted a one-compartment model with half-lives of 10.44–11.37 h (absorption, t
1/2K
a) and 19.77–21.53 h (elimination, t
1/2Ke), and peak concentrations at 20.51–21.96 h (t
peak) in rats. Half-lives and t
peak of PEG-rhIL-6 were longer than those of rhIL-6 previously reported. In the present study, for deposition of PEG-rhIL-6 in
rats, the tissue distribution examination showed that blood was the major organ involved, rather than liver. However, as to
the elimination of PEG-rhIL-6, the major organ was the kidney. The excretion fraction of the injection dose recovered from
urine was 23.32% at 192 h after subcutaneous administration. Less than 6% of PEG-rhIL-6 was eliminated via the feces at 192
h. These results indicate that PEG-rhIL-6 is a good candidate drug formulation for patients with cancer. 相似文献
63.
This paper analyzes the behavior of families in China regarding private tutoring, applying game theory to its discussion of
their actions. It finds that families will definitely give their children private tutoring after school in order to obtain
better educational opportunities in situations where the distribution of educational resources is uneven. According to game
theory, overuse of private tutoring after school will waste societal resources and negatively affect all the players in the
game. It is argued that a key strategy to reduce private tutoring after school is to close the gaps in state provision of
education. 相似文献
64.
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67.
Science & Education - Like all SSI, the COVID-19 pandemic requires decisions that are contentious, involve scientific thinking, and vary across social groups. This investigation determined how... 相似文献
68.
69.
加强流动人口中少数民族的思想政治教育,对于构建社会主义和谐社会具有重要而深远的意义。当前流动人口中少数民族子女思想政治教育工作存在很多问题,究其原因主要有宗教思想的根深蒂固、家庭和学校教育的影响等。如何加强少数民族流动人口子女的思想政治教育问题,需要国家、学校、社会以及家庭共同的努力。 相似文献
70.
近年来,基层就业（代偿）毕业生在工作中常常表现出现场经验不足,技能不够,人际交往能力的不足等等。学校要充分利用对代偿毕业生三年的管理加强对他们的政治思想方面的教育,同时提高在校生和基层就业（代偿）毕业生的创业能力。 相似文献