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排序方式: 共有437条查询结果,搜索用时 31 毫秒
41.
42.
M Yamamoto Y Gotoh K Tamura M Tanaka A Kawakami H Ide A Kuroiwa 《Canadian Metallurgical Quarterly》1998,125(7):1325-1335
The limb muscle precursor cells migrate from the somites and congregate into the dorsal and ventral muscle masses in the limb bud. Complex muscle patterns are formed by successive splitting of the muscle masses and subsequent growth and differentiation in a region-specific manner. Hox genes, known as key regulator genes of cartilage pattern formation in the limb bud, were found to be expressed in the limb muscle precursor cells. We found that HOXA-11 protein was expressed in the premyoblasts in the limb bud, but not in the somitic cells or migrating premyogenic cells in the trunk at stage 18. By stage 24, HOXA-11 expression began to decrease from the posterior halves of the muscle masses. HOXA-13 was expressed strongly in the myoblasts of the posterior part in the dorsal/ventral muscle masses and weakly in a few myoblasts of the anterior part of the dorsal muscle mass. Transplantation of the lateral plate of the presumptive wing bud to the flank induced migration of premyoblasts from somites to the graft. Under these conditions, HOXA-11 expression was induced in the migrating premyoblasts in the ectopic limb buds. Application of retinoic acid at the anterior margin of the limb bud causes duplication of the autopodal cartilage and transformation of the radius to the ulna, and at the same time induces duplication of the muscle pattern along the anteroposterior axis. Under these conditions, HOXA-13 was also induced in the anterior region of the ventral muscles in the zeugopod. These results suggest that Hoxa-11 and Hoxa-13 expression in the migrating premyoblasts is under the control of the limb mesenchyme and the polarizing signal(s). In addition, these results indicate that these Hox genes are involved in muscle patterning in the limb buds. 相似文献
43.
Ide N. Fukuhisa H. Kondo Y. Yoshida T. Nagamatsu M. Junji M. Yamazaki I. Ueno K. 《Solid-State Circuits, IEEE Journal of》1993,28(3):352-361
A CMOS pipelined floating-point processing unit (FPU) for superscalar processors is described. It is fabricated using a 0.5 μm CMOS triple-metal-layer technology on a 61 mm2 die. The FPU has two execution modes to meet precise scientific computations and real-time applications. It can start two FPU operations in each cycle, and this achieves a peak performance of 160 MFLOPS double or single precision with an 80 MHz clock. Furthermore, the original computation mode, twin single-precision computation, double the peak performance and delivers 320 MFLOPS single precision. Its full bypass reduces the latency of operations, including load and store, and achieves an effective throughput even in nonvectorizable computations. An out-of-order completion is provided by using a new exception prediction method and a pipeline stall technique 相似文献
44.
Huntington's disease (HD) is associated with expansion of an unstable CAG repeat. Using antibodies against the synthetic peptide corresponding to the sequence of HD gene IT15, we have identified the HD gene product in normal lymphocytes as a approximately 350kDa protein by immunoblot analysis. Moreover, when a modified SDS-PAGE using a low concentration of methylenbisacrylamide was run longer, abnormal immunoreactive bands larger than normal ones were found exclusively in HD samples. We also found double bands in HD brain homogenate samples. Recently on the other CAG repeat diseases, such as SCA1 and DRPLA, abnormal gene products were also reported. These results demonstrate the existence of the expanded CAG repeat gene products and open a possibility that the expanded polyglutamine stretch may really participate in the pathological process of the CAG repeat diseases. 相似文献
45.
T Ide 《Canadian Metallurgical Quarterly》1998,56(5):1147-1152
46.
47.
T Kanaji H Ozaki T Takao H Kawajiri H Ide M Motoki Y Shimonishi 《Canadian Metallurgical Quarterly》1993,268(16):11565-11572
The complete amino acid sequence of transglutaminase (EC 2.3.2.13) (TGase), which is produced by a microorganism, Streptoverticillium sp. strain s-8112, and catalyzes the acyl transfer reaction between gamma-carboxyamide groups of glutamine residues in proteins and various primary amines, has been established by a combination of fast atom bombardment mass spectrometry and standard Edman degradation of peptide fragments produced by treatment of the TGase with various proteolytic enzymes and purified by a reversed-phase high performance liquid chromatography. The TGase consists of 331 amino acid residues with a chemical molecular weight of 37,863, in agreement with the observed molecular weight (37,869.2 +/- 8.8) determined from its electrospray ionization mass spectrum. The sequence of the enzyme is very different from those of mammalian TGases represented by guinea pig liver enzyme. The enzyme contains a sole Cys residue, which is essential for its catalytic activity. Hydropathy analysis indicated that the secondary structure of the region around the active site Cys residue is similar to those of mammalian TGases. These results suggest that this microbial protein evolved by a different pathway from that of mammalian TGases and acquired acyl transfer activity during the evolutional process. 相似文献
48.
AH Sarker S Ikeda H Nakano H Terato H Ide K Imai K Akiyama K Tsutsui Z Bo K Kubo K Yamamoto A Yasui MC Yoshida S Seki 《Canadian Metallurgical Quarterly》1998,282(4):761-774
The association patterns between maternal anthropometric characteristics (stature, prepregnancy weight, prepregnancy body mass index, pregnancy weight gain) and newborn size (birth weight, length, head circumference) were tested with 10,240 single births taking place between 1985 and 1995 in Vienna, Austria, and 3,452 single births taking place between 1989 and 1995 in Westerstede-Ammerland (Friesland), northern Germany. Maternal size and newborn size differed highly significantly (p < 0.001) between the two genetically and socioeconomically different population groups. Furthermore, the incidence of macrosomia among newborns (birth weight greater than 4000 g) was extraordinarily high (17.9%) in the Frisian group from northern Germany. In both populations taller and heavier women with a higher weight gain during pregnancy gave birth to heavier offspring. Nevertheless, the pregnancy weight gain, which indicates environmental conditions of the mother, had only a minor impact on newborn size compared with stature and prepregnancy weight, which reflect the maternal genetic potential to a higher degree. 相似文献
49.
50.
Effluent quality variation from multicomponent substrates in the activated sludge process 总被引:1,自引:0,他引:1
The objectives of this investigation were: (1) to examine the overall substrate removal of a three component mixture by an acclimated seed using total organic carbon measurements, (2) to observe the rates of removal of each of the three components in the mixture at four different food-to-microorganism ratios (F/M), (3) to show the effects of the composition of the substrate with varying degradability on effluent quality, and (4) to observe the effects of sludge age on total substrate removal.To accomplish these objectives, sludge from a municipal sewage treatment plant was acclimated as seed in a continuous flow, completely mixed laboratory reactor. A multicomponent substrate consisting of a mixture of glucose, phenol and sulfanilic acid, was fed at different F/M ratios. The removal rate was determined as total organic carbon and specific analytical measurements for each substrate in the influent and effluent samples were also made. Various combinations of glucose, phenol and sulfanilic acid were used as a substrate in three runs. This made it possible to observe the removal rate of each substrate in the mixture as related to their individual biodegradability as well as their influent concentrations.The results showed that for the three substrates employed in this study, the overall removal rate, in terms of total organic carbon in a mixed acclimated culture, is the sum of the individual specific removal rates. The effluent quality in terms of soluble TOC was related to the F/M or to the sludge age using Eckenfelder's kinetic model. 相似文献