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101.
The vasculature of the peroneal tissue transfer 总被引:5,自引:0,他引:5
Peroneal vascularized composite-tissue transfer has many useful applications and advantages. An anatomic study of the peroneal artery and vein and their branches was carried out on 80 adult cadaver legs. The number of cutaneous branches averaged 4.8 +/- 1.4 per leg. The length of the cutaneous branches averaged 5.4 +/- 1.5 cm. The external diameters of cutaneous branches at the skin distribution site were 0.6 +/- 0.2 mm for the artery and 0.8 +/- 0.3 mm for the vein. The communicating branches were branched at anterior or posterior tibial vessels 6.1 +/- 2.4 cm proximal to the lateral malleolus. The range of rotation of the island flap when transposed proximally was 14.3 +/- 3.3 cm proximal from the head of the fibula, and when transposed distally, the range of rotation was 16.9 +/- 5.3 cm distally. 相似文献
102.
T Ekida C Nishimura S Masuda S Itoh I Shimada Y Arata 《Biochemical and biophysical research communications》1992,189(1):211-220
In order to locate the receptor-binding region of human interleukin-6 (IL-6), twelve peptide fragments were prepared by digestion of IL-6 with lysylendopeptidase. A significant activity of the receptor-binding was observed only for a peptide Ile88-Lys121, although the activity was estimated at 10(4)-fold less than that of intact IL-6. Solution structure of the peptide Ile88-Lys121 was analyzed by using two-dimensional nuclear magnetic resonance (NMR) spectroscopy. The results indicate the presence of alpha-helices in the regions Leu93-Phe106 and Glu110-Ser119. On the basis of the NMR data, we also prepared two peptides. Four-fold less binding activity than that of the peptide Ile88-Lys121 was observed for the peptide Ile88-Arg105, but no activity for the peptide Glu110-Lys121. These results suggest that the helical peptide Ile88-Arg105 composes a part of the receptor-binding region. 相似文献
103.
R Mizutani I Shimada Y Ueno M Yoda H Kumagai Y Arata 《Biochemical and biophysical research communications》1992,182(2):966-973
Solution conformations of cyclo(GRGDSPA) have been analyzed by the use of two-dimensional proton nuclear magnetic resonance spectroscopy and the dynamical simulated annealing calculation. It has been shown that the RGDS segment in cyclo(GRGDSPA) takes a beta-turn conformation. We have concluded that this beta-turn conformation is essential for the physiological activity of cyclo(GRGDSPA). 相似文献
104.
Y Takagi H Ogawa N Harada H Shimada Y Ishimura Y Takagi 《Biochemical and biophysical research communications》1992,184(1):471-477
Bovine cytochrome P-450(SCC) introduced with the baculovirus host vector system was found to be expressed in Spodoptera frugiperda cells. Cell fractionation analysis indicated that the P-450(SCC) expressed as the precursor form was transported into mitochondria and converted to a mature form. However, this form did not exhibit definite activity for cholesterol side chain cleavage. These findings suggest that most of the P-450(SCC) expressed by this system is an inactive protein within mitochondria that is not folded to the conformation of the active enzyme and/or does not incorporate heme appropriately. 相似文献
105.
Three-dimensional solution structure of the B domain of staphylococcal protein A: comparisons of the solution and crystal structures. 总被引:6,自引:0,他引:6
The three-dimensional solution structure of the recombinant B domain (FB) of staphylococcal protein A, which specifically binds to the Fc portion of immunoglobulin G, was determined by NMR spectroscopy and hybrid distance geometry-dynamical simulated annealing calculations. On the basis of 692 experimental constraints including 587 distance constraints obtained from the nuclear Overhauser effect (NOE), 57 torsion angle (phi, chi 1) constraints, and 48 constraints associated with 24 hydrogen bonds, a total of 10 converged structures of FB were obtained. The atomic root mean square difference among the 10 converged structures is 0.52 +/- 0.10 A for the backbone atoms and 0.98 +/- 0.08 A for all heavy atoms (excluding the N-terminal segment from Thr1 to Glu9 and the C-terminal segment from Gln56 to Ala60, which are partially disordered). FB is composed of a bundle of three alpha-helices, i.e., helix I (Gln10-His19), helix II (Glu25-Asp37), and helix III (Ser42-Ala55). Helix II and helix III are antiparallel to each other, whereas the long axis of helix I is tilted at an angle of about 30 degrees with respect to those of helix II and helix III. Most of the hydrophobic residues of FB are buried in the interior of the bundle of the three helices. It is suggested that the buried hydrophobic residues form a hydrophobic core, contributing to the stability of FB.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
106.
The present study investigated the way a wild bruchid, Kytorhinus sharpianus, distributes its eggs on host pods. First, we counted the number of eggs per pod on the host plant (Sophola flavescens) in the field. The egg-distributions by the overwintered-generation adults in July and by the second-generation adults in mid October did not deviate from Poisson distribution because of small numbers of eggs laid. However, the egg-distribution in late August when many first-generation adults emerged was significantly contagious. The deposition of eggs was determined for three types of pods: (A) clean pods, (B) pods with eggs, and (C) those which eggs had been laid on but were removed from later. The numbers of eggs laid newly on three types of pods were significantly different; A>C>B, suggesting that an oviposition marker pheromone (O.M.P.) caused females to avoid pods on which eggs were deposited. Egg-shells reinforced that response. Monte Carlo simulations for the egg-distribution on pods predicted that even if females avoid pods with heavy egg-load through O.M.P., the egg-distribution becomes contagious when there is a large heterogeneity in quality of the pods. 相似文献
107.
108.
The partial trivoltinism and overwintering of Kytorhinus sharpianus Bridwell (Coleoptera: Bruchidae) was studied in the Kanto district, Japan. The later in the summer eggs were laid by the first-generation adults, the higher was the incidence of larval diapause in the second generation. The incidence of diapause also fluctuated between years, influencing the abundance of third-generation larvae. A relatively large proportion of third-generation larvae did not attain the diapause stage by the beginning of winter. The diapause development of larvae in diapause was completed by mid-January. Immature larvae of the third generation also overwintered and emerged as adults in the spring. 相似文献
109.
Duško Ili? Satoshi Kanazawa Yasuhide Furuta Tadashi Yamamoto Shinichi Aizawa 《Experimental cell research》1996,222(2):298
Focal adhesion kinase (FAK) is a novel nonreceptor protein tyrosine kinase that localizes in focal adhesions. It is expressed in a variety of cell types, and we reported earlier that its deficiency causes a decrease of mobility in mesodermal cells with enhanced formation of focal adhesions. With embryoid bodies generated from embryonic stem cells, we also observed a decrease of mobility in FAK-deficient endodermal cells with enhanced focal adhesion formation. 相似文献
110.
Kazushige Morimoto Eisuke Tsuda Ahmed Abdu Said Eriko Uchida Satoshi Hatakeyama Masatsugu Ueda Takao Hayakawa 《Glycoconjugate journal》1996,13(6):1013-1020
Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol–1 of EPO, there was no further increase in their activity over 12.4 mol mol–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO
erythropoietin
- rHuEPO
recombinant human erythropoietin
- hCG
human chorionic gonadotropin
- BHK
baby hamster kidney
- CHO
Chinese hamster ovary
- NeuAc
N-acetyl neuraminic acid
- Gal
galactose
- HRCs
hemolyser-resistant cells
- WST-1
2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na
- IEF
isoelectric focusing
- pI
isoelectric point 相似文献