Signal transduction pathways mediated by colony stimulating factor-1 receptor

Colony-stimulating factor-1 (CSF-1), which is necessary for cell proliferation and differentiation, regulates both immediate and delayed early responses throughout G1 phase. The binding of CSF-1 to its receptor (CSF-1R) triggers phosphorylation of the receptor and its intrinsic tyrosine kinase. The activated receptor binds directly to cytoplasmic effector proteins, which induce multiple-signal transduction pathways. CSF-1 can induce the c-myc gene expression via Ras and Ets-related proteins. The expression of c-fos/jun family genes is also targeted following the activation of Ras. CSF-1R activates STAT1 and STAT3 to participate in signaling, but JAKs do not appear to contribute to signaling by CSF-1R. CSF-1R activates PI3-kinase, and PI3-ki can interact with downstream proteins by the MAPKK-related pathway independent of Ras/Raf. PC-PLC can enforce signaling in response to CSF-1. Furthermore, the turnover and dephosphorylation by the phosphatase SHPTP1 of CSF-1R are the major mechanism in the negative regulation of signaling by CSF-1R     

应变速率对8090Al-Li合金拉伸性能的影响

用动态拉伸的方法研究了应变速率对 80 90 Al— L i合金拉伸性能的影响 ,应变速率的范围为 10 - 3～ 10 3s- 1。结果表明 ,合金的强度和塑性随应变率的增加而增加。试样的 SEM和 TEM分析发现 :准静态下的断裂为沿晶断裂 ;随着应变率的增加 ,断裂从穿晶准解理断裂过渡到由显微空穴聚集而成的韧窝断裂。高应变率下80 90 Al- L i合金强度和塑性的提高与其变形机制和晶界无沉淀区 (PFZ)的变化有关     

TS分子筛的催化氧化性能研究：Ⅲ.苯酚氧化制苯二酚

研究了自合成的钛硅分子筛（ＴＳ－１）对Ｈ２Ｏ２氧化苯酚制苯二酚反应的催化活性。对反应的温度、时间、催化剂用量、酚：Ｈ２Ｏ２等因素进行了考察：在催化剂用量为苯酚的１０％、酚：Ｈ２Ｏ２（ｍｏｌ）为３：１时,经５７℃／６ｈ反应,Ｈ２Ｏ２的转化率和对产物苯二酚的利用率可达９０％和８０％,还观察到,分子筛的晶粒大小对苯酚的氧化活性影响较大,大晶粒催化剂的内表面利用率较低,从而影响催化活性。     

Molecular cloning and nucleotide sequence of classical swine fever virus strain Shimen

According to the previously published CSFV sequences, 18 paris of partially overlapping primers which span the entire genome of CSFV strain Shimen were designed and synthesized. Each cDNA fragment of strain Shimen was amplified by RT-PCR method from the anticoagulant blood of strain Shimen infected pig. The PCR fragments were cloned into pGEM-T vector respectively and sequenced. The results show that we have obtained the nucleotide sequence of strain Shimen. The viral RNA consists of 12 297 nucleotides including noncoding regions of 373 and 227 bases at the 5′ and 3′ end, respectively, and a single large open reading frame spanning 11 697 nucleotides in the middle, which encodes an amino acid sequence of 3 989 residues with a calculated molecular weight of 437.6×10³. The precisely sequencing of 5′ and 3′ termini is undertaking. Supported by the National Pandeng Project Huang Qianhua: born in 1968. Graduate student     

1,3—二氯—2—丙醇氧化反应的研究

对１,３－二氯－２－丙醇的氧化反应进行了系统的研究,将８４％的硫酸溶液慢慢滴加到包含有１,３－二氯－２丙醇和重铬酸钠水溶液的反应容器中去,将体系保持在２４℃～２６℃拦反应６ｈ,反应完成后,过滤回收１,３－二氯丙酮粗品,粗品用冰水洗涤,然后通过蒸馏经可获得８０．４％的收率的１,３－二氯丙酮,这是一种合成１,３－二氯丙酮较好的工艺,这种工艺与同类文献介绍的方法比较目标产物收率提高１０％,而反应时间缩短     

4种植物生长物质及温度胁迫对绿豆黄化幼苗肌醇磷脂代谢的影响

利用放射性标记和薄层层析（TIC）分离发现2,4－D,GA3和6－BA可不同程度地促进肌醇－1,4,5－三磷酸（IP3）水平的增加．在最适浓度下的作用效果是：GA3＞2,4－D＞6－BA．但脱落酸（ABA）没有引起IP3含量的变化．低温（0℃）和高温（35℃）胁迫亦引起IP3含量的增加．2,4－D,GA3,6－BA和温度胁迫的共同处理对IP3含量的增加有协同作用．表明2,4－D,GA3,6－BA和温度胁迫促进绿豆黄化幼苗肌醇磷脂代谢,ABA也许不参与绿豆黄化幼苗肌醇磷脂代谢．     

7,8-二甲基-3,6-二苯基-5-氧-8-氮螺[2.6]壬-4,9-二酮的合成及其晶体结构

利用手性源（2R,3S）－3,4-二甲基-2-苯基-1,4-氧氮杂-5,7-二酮（1）合成了具有光学活性的7,8-二甲基-3,6-二苯基-5-氧-8-氮螺[2．6]壬-4,9-二酮（3）．测定了化合物（3）的晶体结构,并讨论了在环加成反应中的不对称诱导作用的机理．     

弱酸性介质中Silicalite—1分子筛膜的制备与表征

在ＳｉＯ２－ＴＰＡＢｒ－ＮＨ４Ｆ－Ｈ２Ｏ弱酸性氟离子体系中,在玻璃基片上采用水热晶化法制备了Ｓｉｌｉｃａｌｉｔｅ－１（全硅ＺＳＭ－５）分子筛膜．通过ＸＲＤ,ＳＥＭ分析测试手段对所合成的分子筛膜进行了表征,并对膜合成中硅源,水量等影响因素进行了考察．     

1,3-二氰基中氮茚的合成

介绍了一种吡啶与溴乙腈生成的叶立德,在活性ＭｎＯ２的存在下和丙烯腈反应,制备１,３－二氰基中氮茚的方法。     

非饱和带溶质运移问题的有限元解法

ＳＵＰＧ有限元法应用于土体的非饱和溶质运移问题,导出了其数值表达式,编制了计算程序。以一维入渗问题为例进行了数值计算,与其他方法及野外试验结果进行了对比,表明该方法是正确的、稳定的,可用于非饱和带溶质运移问题的实际计算。