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1.
STUDY DESIGN: The present study analyzed the restriction fragment length polymorphism patterns of alpha 2(XI) collagen, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha genes in patients with ossification of the posterior longitudinal ligament. This study investigates the genetic polymorphism of bone-induced factors in patients with ossification of the posterior longitudinal ligament and compares it with healthy control subjects. OBJECTIVES: To clarify the genetic markers linked to ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: Ossification of the posterior longitudinal ligament is a genetic disease associated with abnormal calcium metabolism involving the posterior longitudinal ligament. Previous genetic studies have not identified the pathologic mechanism of ossification of the posterior longitudinal ligament. Histopathologic studies of ossification of the posterior longitudinal ligament and the animal model, the spinal hyperostotic mouse, have revealed an increase in Type XI collagen and bone morphogenetic protein-2 expression. METHODS: Eighteen Japanese patients with ossification of the posterior longitudinal ligament and 51 healthy, unrelated control subjects were investigated for the restriction fragment length polymorphism patterns of COL11A2, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha, genes with various restriction endonucleases. RESULTS: The gene frequencies of COL11A2 obtained with BamHl (10.0 kb fragment) and HindIII (19.0 kb fragment) observed in patients with ossification of the posterior longitudinal ligament were higher compared with control subjects (0.43 and 0.14, respectively). These differences were statistically significant (BamHl P = 0.018; Hindlll P = 0.046). Two new restriction fragment length polymorphism patterns were detected of the bone morphogenetic protein-2 gene with Mspl and Taql and one already known restriction fragment length polymorphism pattern of the tumor necrosis factor-alpha gene with Ncol. However, they were not significantly different from the control subjects. CONCLUSIONS: Seven restriction fragment length polymorphisms of COL11A2 gene were identified. Two of them (BamHl, 10.0/10.0 kb genotype; HindIII, 19.0/19.0 kb genotype) were significantly different in patients with ossification of the posterior longitudinal ligament.  相似文献   
2.
Lithium naphthalene reacts with acetic acid to give α-anion of lithium acetate. The reaction of this anion with various ketones gives the corresponding β-hydroxy-acids in good yield.  相似文献   
3.
Spinal-Formed Context-Free Tree Grammars   总被引:1,自引:0,他引:1  
In this paper we introduce a restricted model of context-free tree grammars called spine grammars, and study their formal properties including considerably simple normal forms. Recent research on natural languages has suggested that formalisms for natural languages need to generate a slightly larger class of languages than context-free grammars, and for that reason tree adjoining grammars have been widely studied relating them to natural languages. It is shown that the class of string languages generated by spine grammars coincides with that of tree adjoining grammars. We also introduce acceptors called linear pushdown tree automata, and show that linear pushdown tree automata accept exactly the class of tree languages generated by spine grammars. Linear pushdown tree automata are obtained from pushdown tree automata with a restriction on duplicability for the pushdown stacks. Received May 29, 1998, and in revised form April 27, 1999, and in final form May 10, 1999.  相似文献   
4.
Trehalose was compared with glucose in its use as an embedding medium for the preparation of two-dimensional crystals for electron crystallographic structure analysis. Purple membranes (two-dimensional crystals of bacteriorhodopsin) embedded in either sugar were studied in a 'partially hydrated' state as well as after 'drying' of the specimen. Diffraction patterns of the four conditions, all showing spots to a resolution better than 3.0 A, were analysed and merged. In the case of glucose embedded specimens, the merging R-factor obtained from the diffraction patterns of dried specimens was significantly better than the one obtained from partially hydrated specimens. In the case of trehalose embedding, the merging R-factor for partially hydrated specimens was significantly better than the dried one. The trehalose embedded, partially hydrated specimens gave the best merging R-factor in all four cases.  相似文献   
5.
A single-chip H.264 and MPEG-4 audio-visual LSI for mobile applications including terrestrial digital broadcasting system (ISDB-T / DVB-H) with a module-wise, dynamic voltage/frequency scaling architecture is presented for the first time. This LSI can keep operating even during the voltage/frequency transition, so there is no performance overhead. It is realized through a dynamic deskewing system and an on-chip voltage regulator with slew rate control. By the combination with traditional low power techniques such as embedded DRAM and clock gating, it consumes only 63 mW in decoding QVGA H.264 video at 15 frames/sec and MPEG-4 AAC LC audio simultaneously.  相似文献   
6.
The Nivkhi are a native people isolated in the Nogliki region of Sakhalin, Far East Russia, where our group recently recognized human T-cell lymphoma virus type I (HTLV-I) infection. In order to trace the Nivkhi's ethnic background and the HTLV-I carriers, we investigated HLA class I and II allele types of 53 Nivkhi (including four HTLV-I carriers). Major HLA class I alleles of the Nivkhi were A*24, A*02, B*40, B*48, B*27, B*35 with allele frequencies similar to the Orochon, a native people isolated in Northeast China. Major Nivkhi class II alleles were DRB1*0901, DRB1*1401, DRB1*1201, DRB1*1106 with allele frequencies similar to the Ainu in Hokkaido, Japan, but dissimilar to other Asian Mongoloids, including the general Japanese population. The same HLA class I and II allele frequencies are found in both Nivkhi HTLV-I carriers and the background population. A dendrogram of HLA class I alleles showed that the Nivkhi were closely related to the Orochon and Yakut, and remotely related to the Japanese, Ainu and other Asian Mongoloids. Interestingly, the Nivkhi were intermediately related to the Amerindians (Inuit, Tlingit and Andeans), a relationship closer than to the Japanese and Asian Mongoloids. These results suggested the Nivkhi might be related to some genetic group of Northeast Asian Mongoloids like the Orochon and Yakut, being infected with HTLV-I in the distant past before diverging into the current major Mongoloid ethnic groups.  相似文献   
7.
8.
The characteristic features of cast alloys with partially dispersed graphite are wear resistance and toughness. The friction and wear performance, hardness and other surface characteristics of the cast alloys with a high dispersive density of 60% at the casting surfaces were studied.The reciprocating sliding wear volume of aluminium alloy AC7A containing dispersants decreases with an increase in the gravity variable G = 2π2DN2/602g, where D (cm) is the diameter of rotation, N (rev min?1) is the rotational speed and g (cm s?2) is the acceleration due to gravity, but depends on the nature of the dispersants. The effect of casting temperature on the wear loss was not significant. The dispersive density at the near-surface regions which is susceptible to the magnitude of G has a direct effect on the wear loss. A dense dispersant has an adverse effect on wear resistance and lubricity. A relation between surface roughness and casting temperature is also reported.  相似文献   
9.
The new methods of nonlinear image processing are applied to high resolution experimental micrographs of chlorinated copper phthalocyanine taken on the Kyoto 500 kV electron microscope. With these new methods of image processing the phase and amplitude of the specimen transmission function are reconstructed from a defocus series of conventional transmission electron micrographs (bright field). Strong scattering, partial coherence and statistical noise have been included. Both of these new methods are based on the MAP (maximum a posteriori) criterion generalized to include reconstruction from multiple input images. In a companion paper (the first part of this two-part report) the theory behind these methods was presented and in this paper it is tested on actual experimental micrographs. A significant increase in resolution has been obtained with computer image processing. The point-to-point resolution obtained here with computer image processing of 500 kV electron micrographs is of the order of 1.2–1.4 Å which represents a 30–50% increase in resolution.  相似文献   
10.
We have found a factor that induces neurite outgrowth of rat PC12 cells in the culture supernatant of the cell line MLE-15A2. This factor was designated as MDDF. The factor was sensitive to protease, dithiothreitol, and high-temperature treatments. The apparent molecular mass was 80 kDa on Superdex 200 gel filtration. No significant tyrosine phosphorylation was detected after MDDF stimulation in Western blotting analysis with anti-phosphotyrosine antibody, suggesting that the signal transduction may not be mediated by a tyrosine kinase cascade that is involved in signaling of most of the known factors. Activation of MAP kinase was very weak and was seen only 5 min after stimulation, suggesting that prolonged activation of MAP kinase was not required for neurite outgrowth induced by MDDF. Because the biochemical characteristics of MDDF are different from those of any known peptide factors that induce neurite outgrowth of PC12 cells, MDDF may be a novel differentiation factor for PC12 cells.  相似文献   
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