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191.
The speech outcome was studied retrospectively in 140 cleft-palate patients who underwent push-back palatoplasty. Velopharyngeal function and articulation disorders were evaluated serially at 4, 7, 10, and more than 10 years of age. On comparison of velopharyngeal function between 4 years of age and the most recent review (>10 years), it was unchanged in 90 patients (64.3 percent), whereas it showed deterioration in 14 patients and showed improvement in 8 patients. The other 28 patients underwent pharyngeal flap surgery; this group also included patients with functional deterioration. Changes of velopharyngeal function often occurred between 4 and 7 years of age but sometimes occurred after 10 years of age. Articulation disorders were observed in 49 subjects (35.0 percent) at 4 years of age. Many of the patients with glottal stop showed improvement from 4 to 7 years of age. Palatalized articulation showed less improvement than glottal stop (p < 0.01). The number of patients with articulation disorders decreased significantly between 4 years of age and the most recent review (p < 0.001). These findings suggest that speech does not become stable before 10 years of age and that patients with cleft palate should be carefully followed until they are beyond this age.  相似文献   
192.
The blue light receptors termed cryptochromes mediate photomorphological responses in seed plants. However, the mechanisms by which cryptochrome signals regulate plant development remain obscure. In this study, cryptochrome functions were analyzed using the moss Physcomitrella patens. This moss has recently become known as the only plant species in which gene replacement occurs at a high frequency by homologous recombination. Two cryptochrome genes were identified in Physcomitrella, and single and double disruptants of these genes were generated. Using these disruptants, it was revealed that cryptochrome signals regulate many steps in moss development, including induction of side branching on protonema and gametophore induction and development. In addition, the disruption of cryptochromes altered auxin responses, including the expression of auxin-inducible genes. Cryptochrome disruptants were more sensitive to external auxin than wild type in a blue light-specific manner, suggesting that cryptochrome light signals repress auxin signals to control plant development.  相似文献   
193.
Flexible rhombic flap   总被引:1,自引:0,他引:1  
A flexible rhombic flap which can be designed in accordance with the degree of tension of skin bordering a part of the defect has been described. This procedure provides sufficient coverage of a skin defect with very little dog-ear.  相似文献   
194.
Human antigen-presenting cells (APC) which present the antigen to T lymphocytes resulting in a T-lymphocyte proliferative response were found among peripheral mononuclear cells (MNC), by employing purified protein derivative (PPD) as soluble antigen. To assess the adherence capacity of human antigen-presenting cells, MNC were separated by plastic Petri dishes or nylon wool columns. Plastic nonadherent cells were almost equivalent to unseparated cells in antigen-presenting ability. Plastic adherent cells, however, showed better antigen-presenting ability than unseparated cells. On the other hand, cells passed over nylon wool columns showed essentially no ability to present PPD to T lymphocytes. Removal of phagocytic cells by carbonyl iron resulted in about 50–70% reduction in antigen-presenting ability. Carrageenan, which is known to be toxic to macrophages, had no effect on APC. By using both rabbit anti-human Ia-like antiserum and alloantiserum specific for HLA-DR phenotype and complement, it was shown that APC possessed Ia-like antigens, whereas they did not bear surface immunoglobulins. These results indicate that the human APC is probably a cell in the monocyte-macrophage lineage. Allogeneic MNC were used as APC in order to determine whether any genetic restriction exists between MNC as APC and responding T lymphocytes. Optimal stimulation was shown to require identity of mixed leukocyte reaction (MLR)-activating determinants between APC and T lymphocytes. It is, however, obscure whether an HLA-D region restriction exists in these combinations because PPD-pulsed allogeneic MNC lost their ability to elicit even MLR. It is possible that this failure to elicit MLR was caused by T lymphocytes among the MNC used as APC.  相似文献   
195.
Summary An interactivity (Sato, 1969) with respect not only to the interstimulus intervenal between the conditioned and test stimuli but also with respect to the time after the test stimulus was defined as a new generalized recovery function.The contour maps of the above interactivities of the cerebral evoked potentials elicited by the paired flash stimuli and by the conditioned cutaneous and test flash stimuli, respectively, were obtained in the adult human visual cortex.It was suggested to a certain degree by the autocorrelograms of background occipital EEGs and average VEPs that the more prominent VEPs are elicited, the more predominant are the alpha waves in the occipital background EEG, and vice versa. In the contour maps of the interactivity by the paired flash stimuli, cyclic changes of facilitory mountains and occlusive valleys were regular and conspicuous in the subject who exhibited predominant alpha waves in his background EEG, whereas the cyclic changes were less regular and less marked in the subject with few alpha waves in the background EEG.The cyclic changes in the former subject appeared at an interval of about 100 msec at an interstimulus interval of around 100 msec. This acts favorably in the contribution of the cyclic change in interactivity via natural stimulations to the generation of alpha waves in spontaneous EEG. The main facilitory mountains and occlusive valleys in the maps were arranged in a line parallel to the ordinate (axis of the interstimulus interval), which suggest that the conditioned flash will affect in a specific fashion each response compoment elicited via specific afferent inflows in the VEP timelocked to the test flash stimulus. On the contrary, those in the maps obtained by the conditioned cutaneous and test flash stimuli were diagonal to the abscissa (time after the test stimulus) and ordinate, and/or the peaks of facilitory mountains and bottoms of occlusive valleys tended to form a line parallel to the abscissa, which indicates that as the cutaneous somatosensory afferent inflow converges to the visual cortex nonspecific interactivities are exhibited in each component in the VEP.  相似文献   
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198.
The gut microbiota is involved in the pathogenesis of stress-related disorders. Probiotics can benefit the central nervous system via the microbiota–gut–brain axis, which raises the possibility that probiotics are effective in managing depression. In the present study, we examined the effects of heat-killed Lactobacillus helveticus strain MCC1848 in subchronic and mild social defeat stress (sCSDS) model mice (a widely used animal model of depression). MCC1848 supplementation significantly enhanced the interaction time in the social interaction test and sucrose preference ratio in the sucrose preference test, suggesting that MCC1848 improved anxiety- or depressive-like behaviors in sCSDS mice. The gene expression profile analysis of the nucleus accumbens, which plays an important role in stress resilience, indicated that MCC1848 ameliorated sCSDS-induced gene expression alterations in signal transduction or nervous system development. These findings suggest that MCC1848 supplementation is useful as a preventive strategy for chronic-stress-induced depression.  相似文献   
199.
We previously reported that exogenous application of auxin to Arabidopsis seedlings resulted in downregulation of indole-3-acetic acid (IAA) biosynthesis genes in a feedback manner. In this study, we investigated the involvement of the SCFTIR1/AFB-mediated signaling pathway in feedback regulation of the indole-3-pyruvic acid-mediated auxin biosynthesis pathway in Arabidopsis. Application of PEO-IAA, an inhibitor of the IAA signal transduction pathway, to wild-type seedlings resulted in increased endogenous IAA levels in roots. Endogenous IAA levels in the auxin-signaling mutants axr2-1, axr3-3, and tir1-1afb1-1afb2-1afb3-1 also increased. Furthermore, YUCCA (YUC) gene expression was repressed in response to auxin treatment, and expression of YUC7 and YUC8 increased in response to PEO-IAA treatment. YUC genes were also induced in auxin-signaling mutants but repressed in TIR1-overexpression lines. These observations suggest that the endogenous IAA levels are regulated by auxin biosynthesis in a feedback manner, and the Aux/IAA and SCFTIR1/AFB-mediated auxin-signaling pathway regulates the expression of YUC genes.  相似文献   
200.
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