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A case of tracheal reconstruction with a palatal mucoperiosteal graft is reported. The patient is a 75-year-old woman who had the anterior wall of her trachea resected for invading thyroid carcinoma. Palatal mucoperiosteum, which is easy to handle, provided both the lining and supporting tissue for the trachea. Local neck skin was used for covering. This procedure proved very successful.  相似文献   
13.
The pigment cell-specific gene, located at the brown (b)-locus in mouse, encodes the protein that determines the type of melanin synthesized. This protein is known as tyrosinase-related protein, but here we tentatively term it b-locus protein to avoid confusions with the related sequence cross-hybridizing to the tyrosinase gene. In order to identify the mutation at the b-locus, we have cloned and characterized the b-locus protein gene of BALB/c mouse (b/b, c/c). The gene is about 18 kb long and organized into 8 exons and 7 introns. Sequence analysis of the b-locus protein gene reveals four base changes within the protein-coding regions: two missense mutations and two silent mutations. Two missense mutations result in the Cys to Tyr substitution at position 86 (codon 110) and the Arg to His substitution at position 302 (codon 326) of a b-locus protein molecule. Using allele-specific amplification, we confirmed that these missense mutations are actually present in the genomic DNA of two b-mutant strains examined, BALB/c and DBA/2 (b/b, C/C) mice, suggesting that these mutations are specific for the mutant mice at the b-locus. Moreover, we are able to show that the b-locus protein containing Tyr 86 is not reactive with the anti-b-locus protein monoclonal antibody, TMH-1, in transient expression assays.  相似文献   
14.
A. SUEMORI, K. NAKAJIMA, R. KURANE AND Y. NAKAMURA. 1996. Rhodococcus erythropolis strain S1 formed enzymes essential to the degradation of phthalate when grown in phthalate-minimal medium. The reaction responsible for the dihydroxylation of the phthalate-benzene ring was concluded to be catalysed by membrane-associated phthalate 3,4-dioxygenase (PO). Of the other enzymes involved, 3,4-dihydro-3,4-dihydroxyphthalate 3,4-dehydrogenase (PH) and 3,4-dihydroxyphthalate 2-decarboxylase (PC) appeared likely to be membrane-bound, while protocatechuate 3,4-dioxygenase appeared to be present in the cytoplasm. Based on the data, the membrane-bound PO and PH apparently form an enzyme complex, which is associated with the NADH-regenerating system.  相似文献   
15.
A fuzzy expert system was developed for online diagnosing and controlling of bioprocesses. The system was constructed in object-oriented Smalltalk/V for diagnosing and controlling of bioprocesses. Lactic acid fermentation with an industrial strain ofLactobacillus casei was chosen as the model system. The performance of the fuzzy expert system and the knowledge base utilizing experts' knowledge and several facts obtained from the experiments were successfully validated with on-line fermentations. The fuzzy expert system could diagnose a fault on-line and give reasonable advice to the process operator. In order to achieve the diagnosing faculty, a database, a knowledge base, and both backward and forward chaining procedures were implemented employing the object-oriented programming environment. A defuzzifier was implemented in the system to achieve on-line control. In order to realize a decision-making system with a human operator and a fuzzy expert system, a new control strategy namedAdvice was also introduced. Several cultivations were carried out in order to collect knowledge on the effects concerned with inoculum properties to the process and to construct a database including standard time-course profiles. The performance of the fuzzy expert control system was successfully tested with on-line experiments.Visiting scientist from HUT at RIKEN  相似文献   
16.
The chorion of unfertilized medaka Oryzias latipes eggs consists of two major proteins (77–73 and 49 kDa) and a minor 150 kDa protein. Upon fertilization, these major chorion proteins are polymerized to insoluble high molecular weight proteins via the temporary formation of several new proteins (132, 114, 62 and 61 kDa). Increasing chorion toughness is closely related to the formation of high molecular weight proteins and the increasing insolubility of the chorion proteins. The changes in chorion proteins and hardening could be induced in vitro in isolated chorions by an egg exudate, which includes cortical alveolar contents. The effects of temperature and pH on the egg exudate-induced changes in chorion proteins were examined in the present study. The major proteins could be digested by proteolytic enzymes. The 49 kDa protein was PAS-positive. Analysis with polyclonal antibodies against the major proteins demonstrated that the temporarily formed 62 and 61 kDa proteins were derived from the 77–73 kDa protein and that higher molecular weight proteins, newly formed in the process of chorion hardening, contained the same epitopes as did the 77–73 and 49 kDa proteins. The results suggest that the changes in chorion proteins of the medaka egg at the time of fertilization can be induced by an enzyme(s) released from the egg cortex into the perivitelline space.  相似文献   
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Phyllolitorin and Leu8-phyllolitorin, two nonapeptide amides from the skin of the South American frog Phyllomedusa sauvagei, are representatives of a novel bombesin subfamily, characterized by the occurrence in their molecule of a serine residue substituting the usual histidine residue at position 3 from the C-terminus. In parallel bioassay on ten different smooth muscle preparations and rat blood pressure, phyllolitorin and Leu8-phyllolitorin were virtually equiactive, but the two peptides appeared remarkably less potent that litorin in all test preparations, except the rat urinary bladder. The shape of contractions produced by the phyllolitorins and promptness of cessation of their action upon washing seem to indicate a looser binding of these peptides to their receptors and/or a more rapid inactivation, in comparison to litorin.  相似文献   
19.
Bile salts present in gallbladder of wild and cultured red seabream, Pagrosomus major, a marine teleost were analyzed. The bile from wild red seabream was found to contain two previously unknown bile salts along with two known bile salts, taurocholate and taurochenodeoxycholate. Isolation of each bile salt was performed by column chromatography. Fast atom bombardment mass spectra of the unknown bile salts showed the molecular ions (M-H)- of m/z 544 and 528 which are shifted 30 mass units upfield compared to those (m/z 514 and 498) of taurocholate and taurochendeoxycholate, respectively; this is consistent with the presence of cysteinolic acid (mol wt 155) instead of taurine (mol wt 125). Enzymatic hydrolysis of the bile salts released cholic acid and chenodeoxycholic acid, respectively, and an amino acid that was identified as D-cysteinolic acid by direct comparison with an authentic sample. From these results, the bile salts in the bile of wild red seabream were identified as the conjugates of cholic acid and chenodeoxycholic acid with cysteinolic acid. 1H- and 13C-magnetic resonance spectra of the bile salts were also consistent with the proposed structure. The cysteinolic acid conjugates were found only in wild and not in cultured red seabream; this distinction seems to result from differences in dietary cysteinolic acid.  相似文献   
20.
Induction of hyaluronic acid synthetase by estrogen in the mouse skin   总被引:4,自引:0,他引:4  
Hyaluronic acid synthetase activity was measured in male mouse skin following the topical application of estradiol in vivo. The enzyme activity increased in parallel with the hyaluronic acid content of the skin, and showed a similar response in the skin of ovariectomized female mice. The increase in enzyme activity was reduced by the anti-estrogen agents, tamoxifene citrate and clomiphene citrate, which block competitively the binding of estrogen to the estrogen receptor. The increase in hyaluronic acid synthetase activity was also reduced by topical application of cycloheximide or by subcutaneous injection of actinomycin D. The results suggest that the stimulation of hyaluronic acid synthesis in mouse skin in response to estrogen treatment is mediated through estrogen receptors and involves the induction of the enzyme hyaluronic acid synthetase.  相似文献   
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