免疫组织化学实验技术研究

以SD大鼠睾丸为实验材料,应用免疫组织化学方法进行染色,探讨免疫组化石蜡切片实验中各条件对实验结果的影响．结果表明,玻片处理、试剂纯净度、取材到封片等,都对实验结果会产生较大影响．而脱水、抗原修复、过氧化氢、一抗及正常羊血清孵育过程是影响实验的关键因素．     

超混沌五阶自治电路的设计及实验结果

设计了一个五阶自治的超混沌电路。该电路虽然只含有一个负阻、一个分段线性项,电路结构简单,却可以产生具有三个正性Ｌｙａｐｕｎｏｖ指数的混沌信号。将该电路用于保密通讯中,可提高密文的抗破译强度。     

关于R.Bruck的一个结果

通过考虑少极点的非常数亚纯函数与其线性微分多项式分担一个小函数的情况，改进了R.Bruck和Q.C.Zhang及A.Al-Khaladi等人的结果。     

空间组合拱桥模型试验测试结果分析

在文献[1]的基础上,对中山一桥模型试验测试结果进行了初步分析.测试结果表明:该桥动力性能较好,无明显的薄弱部位;在恒载及最不利荷载作用下,模型桥梁的挠度、水平位移、应力均在规范允许的范围内,最大水平推力较小,在顺桥向及横桥向均可以实现自平衡,各拱肋刚度是比较匹配的,说明该桥设计构思是科学合理的,总体上是安全的.     

空问组合拱桥模型试验测试结果分析

在文献[1]的基础上，对中山一桥模型试验测试结果进行了初步分析．测试结果表明：该桥动力性能较好，无明显的薄弱部位；在恒载及最不利荷载作用下，模型桥梁的挠度、水平位移、应力均在规范允许的范围内．最大水平推力较小，在顺桥向及横桥向均可以实现自平衡，各拱肋刚度是比较匹配的，说明该桥设计构思是科学合理的，总体上是安全的．     

大学生生物化学实验技能竞赛结果分析

为了解湖北省高校生物学实验教学状况,促进生物学实验教学改革深入发展,经湖北省教育厅批准,自2010年开始湖北省每两年举行一次生物学实验技能竞赛。生物化学作为基础学科,实验技能考核单独列为竞赛项目。第二届生物化学实验竞赛结果显示,学生在实验前期准备,常规仪器的使用及基本的实验过程的掌握等方面成绩较好,得分率在90%以上,而在实验结果的处理及分析环节相对较弱,得分率为77%。另外部分学生在一些实验的细节上失分较多。因此,在今后的生物化学实验教学中,在继续加强基本实验操作技能训练的同时,还要提高学生对实验结果进行分析及处理的能力,以及对实验中一些细节问题的关注和重视,以促进学生全面实验技能的提高。     

关于R．Brück的一个结果

通过考虑少极点的非常数亚纯函数与其线性微分多项式分担一个小函数的情况，改进了R．Brück和Q．C．Zhang及A．A1一Khaladi等人的结果．     

Superconductivity in CaCuO2 as a result of field-effect doping.

Understanding the doping mechanisms in the simplest superconducting copper oxide-the infinite-layer compound ACuO2 (where A is an alkaline earth metal)-is an excellent way of investigating the pairing mechanism in high-transition-temperature (high-Tc) superconductors more generally. Gate-induced modulation of the carrier concentration to obtain superconductivity is a powerful means of achieving such understanding: it minimizes the effects of potential scattering by impurities, and of structural modifications arising from chemical dopants. Here we report the transport properties of thin films of the infinite-layer compound CaCuO2 using field-effect doping. At high hole- and electron-doping levels, superconductivity is induced in the nominally insulating material. Maximum values of Tc of 89 K and 34 K are observed respectively for hole- and electron-type doping of around 0.15 charge carriers per CuO2. We can explore the whole doping diagram of the CuO2 plane while changing only a single electric parameter, the gate voltage.     

The crystal structure of DNA mismatch repair protein MutS binding to a G x T mismatch

DNA mismatch repair ensures genomic integrity on DNA replication. Recognition of a DNA mismatch by a dimeric MutS protein initiates a cascade of reactions and results in repair of the newly synthesized strand; however, details of the molecular mechanism remain controversial. Here we present the crystal structure at 2.2 A of MutS from Escherichia coli bound to a G x T mismatch. The two MutS monomers have different conformations and form a heterodimer at the structural level. Only one monomer recognizes the mismatch specifically and has ADP bound. Mismatch recognition occurs by extensive minor groove interactions causing unusual base pairing and kinking of the DNA. Nonspecific major groove DNA-binding domains from both monomers embrace the DNA in a clamp-like structure. The interleaved nucleotide-binding sites are located far from the DNA. Mutations in human MutS alpha (MSH2/MSH6) that lead to hereditary predisposition for cancer, such as hereditary non-polyposis colorectal cancer, can be mapped to this crystal structure.     

A Note on a Result of Pesin

Ｆｏｒｓｔｕｄｙｉｎｇｔｈｅｄｉｍｅｎｓｉｏｎｔｈｅｏｒｙｏｆｄｙｎａｍｉｃａｌｓｙｓｔｅｍ ,ＰｅｓｉｎｉｎｔｒｏｄｕｃｅｄＣａｒａｔｈ啨ｏｄｏｒｙｓｔｒｕｃｔｕｒｅ(Ｃ ｓｔｒｕｃｔｕｒｅ)ｗｈｉｃｈｌｅａｄｓｔｏｔｈｅｇｅｎｅｒａｌｉｚａｔｉｏｎｓｏｆｂｏｔｈｃｌａｓｓｉｃａｌｄｉｍｅｎｓｉｏｎｓａｎｄｔｏｐｏｌｏｇｉｃａｌｐｒｅｓｓｕｒｅｓ;ＨｅｃｏｎｓｉｄｅｒｅｄｔｗｏｔｙｐｉｃａｌＣ ｓｔｒｕｃｔｕｒｅｓｗｈｉｃｈｃｏｎｎｅｃｔｓｒｅｓｐｅｃｔｉｖｅｌｙｔｈｅｏｐｅｎｃｏｖｅｒｉｎｇａｎｄ…     

The vsr gene product of E. coli K-12 is a strand- and sequence-specific DNA mismatch endonuclease

In Escherichia coli K-12, the Dcm methyltransferase catalyses methylation of the inner cytosine residue in the sequence CCA/TGG. Hydrolytic deamination of 5-methylcytosine bases in DNA leads to thymine residues, and hence to T/G mismatches, pre-mutagenic DNA lesions consisting of two natural DNA constituents and thus devoid of an obvious marker of the damaged DNA strand. These mismatches are corrected by the VSP repair pathway, which is characterized by very short patches of DNA repair synthesis. It depends on genes vsr and polA and is strongly stimulated by mutL and mutS. The vsr gene product (Vsr; Mr 18,000) was purified and characterized as a DNA mismatch endonuclease, a unique and hitherto unknown type of enzyme. Vsr endonuclease nicks double-stranded DNA within the sequence CTA/TGN or NTA/TGG next to the underlined thymidine residue, which is mismatched to 2'-deoxyguanosine. The incision is mismatch-dependent and strand-specific. These results illustrate how Vsr endonuclease initiates VSP mismatch repair.     

关于K4-同胚图色唯一性的新结果

令K4(i,j,k,l,m,n)表示两两三度点间的路长分别为i,j,k,l,m,n的K4-同胚图.研究6条路的长均大干1且有3条路的长均等于a(a＞2),而其余3条路的长都小干a且互不相等的K4-同胚图的着色,得到一类色唯一的K4同胚图.     

某电厂技改工程桩基试验分析

全面详尽的试验数据,可以校验地质报告提供的数据,给设计人员提供设计依据,确保工程安全,节约工程投资。本文结合工程实例介绍了静载试验、桩身应力测试、高应变试验、低应变试验的方法,综合试验数据,在科学安全的前提下,给出了符合当地地质实际的单桩极限承载力标准值。