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Reconstruction of chest wall and axilla are performed in 11 patients using a contralateral latissimus dorsi musculocutaneous flap. The entire lattisimus dorsi muscle, including the fascial portion, safely carried an island of skin from the area of the lumbodorsal fascia to the contralateral axilla. The flap was transposed to the defect through a tunnel between the pectoralis major and minor muscles. Most patients who needed reconstruction of the chest wall and axilla had compromised ipsilateral vasculature that prohibited its use in a pedicled flap but had an intact contralateral chest wall, axilla, and thoracodorsal vessels. Therefore, this procedure was performed easily in comparison with a free flap or pedicled omental flap. This is a new, valuable application for the versatile latissimus dorsi musculocutaneous flap.  相似文献   
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Journal of Plant Research - Silicon (Si) accumulation differs greatly among plant species, as revealed by an increasing number of studies reporting whole-leaf Si concentration for a wide range of...  相似文献   
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Summary Extensive screening of the mitogens lipopolysaccharide (LPS), pokeweed mitogen (PWM), andStaphylococcus aureus Cowan I (SAC I), alone and in combination and with and without interleukin (IL) was performed forin vitro activation of regional lymph node lymphocytes from lung cancer patients for the production of human IgG, IgM, and IgA. As assessed by electrofusion of the lymphocytes following their exposure to these agents with mouse myeloma cells and incubation of the fused hybridoma, a remarkable stimulatory effect was shown by LPS and particularly by LPS plus IL-4, which was substantially greater than that of either SAC I or PWM with or without various IL. Optimization studies indicated that the addition of PWM to LPS and IL-4 in the culture medium further stimulated the human antibody (Ab) production, and that the optimal formulation for stimulations of human IgG production was a culture medium containing 20 μg/ml of LPS, 1/500 of PWM, and 100 u/ml of IL-4.  相似文献   
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Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere.  相似文献   
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Administration of phalloidin in vivo to rats causes marked changes in the distribution of actin and myosin in hepatocytes, which accompanies reduced bile flow. We have found that in hepatocytes treated with phalloidin for 3 and 7 days, cellular myosin content increased about 1.5-fold and 4.7-fold, respectively. In addition, total cell protein content and several marker enzyme activities were also elevated by 30-120% depending on the duration of phalloidin treatment. These observations allow us to speculate that phalloidin somehow elicits inhibition of cellular protein degradation, which results in the increase of these protein levels. To examine this possibility further, we analyzed leupeptin-induced density shift of phagolysosomes. In normal liver, the injection of leupeptin/E64c caused an increase in the density of both heterolysosomes and autolysosomes, due to retarded digestion of sequestered proteins as a result of the inhibition of lysosomal cathepsins. Accumulation, in these denser autolysosomes, of lactic dehydrogenase, pyruvate kinase, aldolase, and myosin was demonstrated by enzyme assays and immunoblot analysis. In the phalloidin-treated liver, the increase in the density of autolysosomes and the accumulation of above cytoplasmic enzymes were markedly inhibited. However, phalloidin did not affect the shift in the density of heterolysosomes. From these data, we concluded that autolysosome formation was specifically hindered in phalloidin-treated rat hepatocytes, which results in the reduction of autophagic protein degradation and eventual increase in intracellular protein levels.  相似文献   
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It is shown that rat liver isoleucyl-tRNA formation in the presence of Mg2+ is inhibited by poly(G), poly(I) or ribosomes and that this inhibition is prevented by polyamines. The inhibition is found to be noncompetitive with respect to tRNA.  相似文献   
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Puf5, a Puf-family RNA-binding protein, binds to 3´ untranslated region of target mRNAs and negatively regulates their expression in Saccharomyces cerevisiae. The puf5Δ mutant shows pleiotropic phenotypes including a weakened cell wall, a temperature-sensitive growth, and a shorter lifespan. To further analyze a role of Puf5 in cell growth, we searched for a multicopy suppressor of the temperature-sensitive growth of the puf5Δ mutant in this study. We found that overexpression of CLB2 encoding B-type cyclin suppressed the temperature-sensitive growth of the puf5Δ mutant. The puf5Δ clb2Δ double mutant displayed a severe growth defect, suggesting that Puf5 positively regulates the expression of a redundant factor with Clb2 in cell cycle progression. We found that expression of CLB1 encoding a redundant B-type cyclin was decreased in the puf5Δ mutant, and that this decrease of the CLB1 expression contributed to the growth defect of the puf5Δ clb2Δ double mutant. Since Puf5 is a negative regulator of the gene expression, we hypothesized that Puf5 negatively regulates the expression of a factor that represses CLB1 expression. We found such a repressor, Ixr1, which is an HMGB (High Mobility Group box B) protein. Deletion of IXR1 restored the decreased expression of CLB1 caused by the puf5Δ mutation and suppressed the growth defect of the puf5Δ clb2Δ double mutant. The expression of IXR1 was negatively regulated by Puf5 in an IXR1 3´ UTR-dependent manner. Our results suggest that IXR1 mRNA is a physiologically important target of Puf5, and that Puf5 and Ixr1 contribute to the cell cycle progression through the regulation of the cell cycle-specific expression of CLB1.  相似文献   
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