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Spinocerebellar ataxia and HLA linkage: risk prediction by HLA typing   总被引:2,自引:0,他引:2  
To determine the possibility of genetic linkage of spinocerebellar ataxia with the histocompatibility loci, we performed HLA typing and linkage analysis on 19 members of a kindred in which spinocerebellar ataxia was segregating in an autosomal dominant inheritance pattern. The ataxia locus was located on chromosome 6 at 12-cM distance from the HLA complex with lod score of 3.15 (odds is greater than 1400:1 favoring linkage over chance findings). Thus, the presence of the ataxia gene in members of this kindred at risk can be predicted with about 90 per cent accuracy by means of HLA typing in informative matings.  相似文献   
23.
We realized cationic substitutions in Sr2IrO4 and measured resistivity, thermoelectric power, and the Hall coefficient. A two-carrier model, reflecting the presence of thermally activated carriers at high temperature, qualitatively explains the behavior of the Hall coefficient of Sr1.95La0.05IrO4 in comparison with Sr2IrO4. Concerning the substitution of Ir by different transition metals, Pt with 5d orbitals does not affect the transport properties, contrary to Ti and Rh with 3d and 4d orbitals, respectively. This may be explained by strong spin–orbit coupling involved in Ir and Pt, in comparison with 3d or 4d transition metals.  相似文献   
24.
We have successfully developed a cosmetic film with polymerized cholesteric material. The film features a variety of colors by helical pitch gradients, diffusive texture, and arbitrary color patterns. It hides the display when turned off, and transmits display images when turned on. We believe it could change the display in the OFF‐state from the conventional black wall to specially designed decorations. In addition, they can be applied to hidden sensors.  相似文献   
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This paper presents eigenvector algorithms (EVAs) for blind deconvolution of multiple-input, multiple-output infinite impulse response channels (convolutive mixtures). An attractive feature of one of the proposed EVAs is that it is insensitive to Gaussian noises which are added to the outputs of the channels; hence, the proposed EVA is referred to as a "robust" eigenvector algorithm. Simulation results show the validity of the proposed EVAs.  相似文献   
27.
At fertilization, sea urchin eggs undergo a series of activation events, including a Ca2+ action potential, Ca2+ release from the endoplasmic reticulum, an increase in intracellular pH, sperm pronuclear formation, MAP kinase dephosphorylation, and DNA synthesis. To examine which of these events might be initiated by activation of phospholipase Cgamma (PLCgamma), which produces the second messengers inositol trisphosphate (IP3) and diacylglycerol, we used recombinant SH2 domains of PLCgamma as specific inhibitors. Sea urchin eggs were co-injected with a GST fusion protein composed of the two tandem SH2 domains of bovine PLCgamma and (1) Ca2+ green dextran to monitor intracellular free Ca2+, (2) BCECF dextran to monitor intracellular pH, (3) Oregon Green dUTP to monitor DNA synthesis, or (4) fluorescein 70-kDa dextran to monitor nuclear envelope formation. Microinjection of the tandem SH2 domains of PLCgamma produced a concentration-dependent inhibition of Ca2+ release and also inhibited cortical granule exocytosis, cytoplasmic alkalinization, MAP kinase dephosphorylation, DNA synthesis, and cleavage after fertilization. However, the Ca2+ action potential, sperm entry, and sperm pronuclear formation were not prevented by injection of the PLCgammaSH2 domain protein. Microinjection of a control protein, the tandem SH2 domains of the phosphatase SHP2, had no effect on Ca2+ release, cortical granule exocytosis, DNA synthesis, or cleavage. Specificity of the inhibitory action of the PLCgammaSH2 domains was further indicated by the finding that microinjection of PLCgammaSH2 domains that had been point mutated at a critical arginine did not inhibit Ca release at fertilization. Additionally, Ca2+ release in response to microinjection of IP3, cholera toxin, cADP ribose, or cGMP was not inhibited by the PLCgammaSH2 fusion protein. These results indicate that PLCgamma plays a key role in several fertilization events in sea urchin eggs, including Ca2+ release and DNA synthesis, but that the action potential, sperm entry, and male pronuclear formation can occur in the absence of PLCgamma activation or Ca2+ increase.  相似文献   
28.
材料的快中子溅射性能直接关系到裂变和聚变反应材料的选择。在测量得到的(n,2n),(n,α),(n,p)和(n,np)核反应的快中子溅射产额的实验数据基础上,结合理论计算结果,得到了1个适合于计算上述4种核反应的约化溅射产额的修正的理论计算公式。  相似文献   
29.
Photochemical and photoelectrochemical properties of ruthenium tris(2,2′-bipyridine) (Ru2+)-viologen (V2+) linked disulfides [RuCnVC6S]2 (n (number of methylene groups)=3, 7) with different spacer-chain lengths and Ru2+ disulfides [RuCmS]2 (m=13, 17) were compared. The luminescence intensity in CH3CN was in the order of [RuC13S]2≈[RuC17S]2>[RuC7VC6S]2[RuC3VC6S]2, implying efficient photoinduced electron-transfer between Ru2+ and V2+ moieties in the linked compounds. The monolayer assembly of the compound was fabricated on a gold surface. In the presence of triethanolamine, the anodic photocurrent was clearly observed from the RuCnVC6S/Au (n=3, 7) electrode (gold electrode modified with [RuCnVC6S]2), and its intensity was substantially larger for n=7 than for n=3. Photocurrent action spectra for the RuCnVC6S/Au (n=3, 7) electrodes were well correlated with the corresponding electronic absorption spectra in solution. The photocurrent from the RuC7VC6S/Au electrode was reduced more effectively by the coexistence of a water-soluble viologen as compared with the RuC3VC6S/Au electrode. The photocurrent from the RuCmS/Au (m=13, 17) electrode was very small. The results suggest that the spacer-chain length between the Ru2+ and the V2+ moieties profoundly affects the Ru2+-sensitized photocurrent.  相似文献   
30.
Prior austenite grain size dependence of the low temperature impact toughness has been addressed in the bainitic weld metals by in situ observations.Usually,decreasing the grain size is the only approach by which both the strength and the toughness of a steel are increased.However,low carbon bainitic steel with small grain size shows a weakening of the low temperature impact toughness in this study.By direct tracking of the morphological evolution during phase transformation,it is found that large austenite grain size dominates the nucleation of intragranular acicular ferrite,whereas small austenite grain size leads to grain boundary nucleation of bainite.This kinetics information will contribute to meet the increasing low temperature toughness requirement of weld metals for the storage tanks and offshore structures.  相似文献   
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