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71.
We recently reported on a linkage study within a Quarter Horse lineage segregating hyperkalaemic periodic paralysis (HYPP), an autosomal dominant condition showing potassium-induced attacks of skeletal muscle paralysis. HYPP co-segregated with the equine adult skeletal muscle sodium channel alpha subunit gene, the same gene that causes human HYPP. We now describe the Phe to Leu mutation in transmembrane domain IVS3 which courses the horse disease. This represents the first application of molecular genetics to an important horse disease, and the data will provide an opportunity for control or eradication of this condition. 相似文献
72.
对新球虫灵,喹乙醇,免健宝Ⅰ号,Ⅱ号配套复合饲料添加剂进行的幼兔饲养对比试验结果表明:以免健宝Ⅰ、Ⅱ号配套复合饲料添加剂联合效果为最佳,其它依次为单用兔健宝Ⅱ号、兔健宝Ⅰ号、喹乙醇,新球虫灵。而且兔健宝Ⅰ、Ⅱ号配套复合饲料添加剂有易混匀,简化配合饲料工序、节省饲料及增重快等优点。 相似文献
73.
74.
To validate procedures of rational drug design, it is important to develop computational methods that predict binding sites between a protein and a ligand molecule. Many small molecules have been tested using such programs, but examination of protein-protein and peptide-protein interactions has been sparse. We were able to test such applications once the structures of both the maltose-binding protein (MBP) and the ligand-binding domain of the aspartate receptor, which binds MBP, became available. Here we predict the binding site of MBP to its receptor using a 'binary docking' technique in which two MBP octapeptide sequences containing mutations that eliminate maltose chemotaxis are independently docked to the receptor. The peptides in the docked solutions superimpose on their original positions in the structure of MBP and allow the formation of an MBP-receptor complex. The consistency of the computational and biological results supports this approach for predicting protein-protein and peptide-protein interactions. 相似文献
75.
76.
The ability of Enterobacter agglomerans to transform naturally occurring nucleosides into nucleotides has been utilized to transform newly synthesized pyrimidine acyclonucleosides into the corresponding acyclonucleotides. Unselected bacteria were used as the source of nucleoside phosphotransferase, the phosphate group donor being 4-nitrophenyl phosphate in the presence of Zn2+ ions. Optimal reaction conditions are outlined. 相似文献
77.
In myelinated nerves, segregation of voltage-dependent sodium channels to nodes of Ranvier is crucial for saltatory conduction along axons. As sodium channels associate and colocalize with ankyrin at nodes of Ranvier, one possibility is that sodium channels are recruited and immobilized at axonal sites which are specified by the subaxolemmal cytoskeleton, independent of glial cell contact. Alternatively, segregation of channels at distinct sites along the axon may depend on glial cell contact. To resolve this question, we have examined the distribution of sodium channels, ankyrin and spectrin in myelination-competent cocultures of sensory neurons and Schwann cells by immunofluorescence, using sodium channel-, ankyrin- and spectrin-specific antibodies. In the absence of Schwann cells, sodium channels, ankyrin and spectrin are homogeneously distributed on sensory axons. When Schwann cells are introduced into these cultures, the distribution of sodium channels dramatically changes so that channel clusters on axons are abundant, but ankyrin and spectrin remain homogeneously distributed. Addition of latex beads or Schwann cell membranes does not induce channel clustering. Our results suggest that segregation of sodium channels on axons is highly dependent on interactions with active Schwann cells and that continuing axon-glial interactions are necessary to organize and maintain channel distribution during differentiation of myelinated axons. 相似文献
78.
本文研究了在不同pH值下吐温—80.Tritonx—100.SLS三种表面活性剂四—(对-三甲铵苯基)卟啉Soret带的影响。 相似文献
79.
生物序列分析 总被引:1,自引:0,他引:1
这次演讲将回顾近 1 0多年来应用某些随机模型于生物序列分析的研究工作 .这些模型本身有很长的历史 ,可追溯到 3 0多年以前 ,尽管从那时起 ,这些模型已经产生了很多新的变种 .在生物序列分析中模型的作用是归总那些涉及到在生物信息学中已知的模体 (motif)或域 (domain)的信息 ,并且提供一种工具在另一序列片段中寻找模体或域的实例 (instance) .我们将逐步介绍模体模型 ,从非常简单的 ,非随机情况开始 ,进而是更复杂的情况 ,直至近来的关于模体的剖面隐马氏模型 .第二个例子是来自利用一个或两个物种的序列数据进行基因发现 ,其中广义隐马氏模型或广义成对 (pair)隐马氏模型已被证实非常有效 相似文献
80.
The failing heart. 总被引:19,自引:0,他引:19
Cardiomyopathies are disorders affecting heart muscle that usually result in inadequate pumping of the heart. They are the most common cause of heart failure and each year kill more than 10,000 people in the United States. In recent years, there have been breakthroughs in understanding the molecular mechanisms involved in this group of conditions, with knowledge of the genetic basis for cardiomyopathies perhaps seeing the largest advance, enabling clinicians to devise improved diagnostic strategies and preparing the stage for new therapies. 相似文献