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Congenital left atrial appendage ostial stenosis is a very rare congenital cardiac condition. We present the case of an extremely premature infant with congenital left atrial appendage ostial stenosis diagnosed by transthoracic echocardiographic imaging.  相似文献   
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Introduction: Changes in muscle architecture induced by eccentric knee extensor training remain unclear, as well the adaptive responses of synergistic knee extensor muscles with different geometrical designs. Methods: Ultrasonography images were taken from rectus femoris (RF) and vastus lateralis (VL) of 20 male volunteers before and after a non‐training control period of 4 weeks, and additional evaluations were performed after 4, 8, and 12 weeks of isokinetic eccentric training. Results: RF and VL had significant changes in muscle architecture within the first 4 training weeks, and the adaptive response throughout the intervention was similar. Muscle thickness increased by around 7–10%, fascicle length increased 17–19%, and pennation angle was unchanged. Conclusions: Increased muscle thickness due to eccentric training was related to increased fascicle length and not to pennation angle changes. Although RF and VL have a different fascicular geometry, they had similar morphological adaptations to eccentric training. Muscle Nerve 48 : 498–506, 2013  相似文献   
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Results of nonlinear finite element analysis support the Schachar theory of accommodation and demonstrate that the long-held Helmholtz theory of accommodation is impossible.  相似文献   
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Immunoglobulin G subclass concentrations were measured in paired foetal (cord) and maternal serum specimens at delivery from 27 IgA-deficient (serum IgA < 0.01 g/l) and 15 control women. IgA-deficient women had significantly higher serum IgGl and IgG3 concentrations than control women but 2 of the group had concomitant IgG2/IgG4 deficiency and a further 12 had low IgG4 concentrations (serum IgG4 < 0.025 g/l). Foetal serum also had significantly higher IgGl concentrations than control foetal serum but lower IgG2 and IgG4 levels. Concentrations of IgG subclasses and IgM were measured in breast milk collected on the fifth day postpartum from 19 of these IgA-deficient and 18 control women. Between-group differences in IgG subclass levels resembled those in serum. Compared with serum, proportionally less IgG3 was present in milk in both groups although the contribution of IgG3 to total IgG was not less than that of IgG4. Slightly higher IgM was found in milk from the IgA-deficient mothers.  相似文献   
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Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation.  相似文献   
38.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease.  相似文献   
39.
牙科医生对口腔卫生服务体系的评价   总被引:1,自引:0,他引:1  
目的 :分析牙科医生的日常工作量和牙医对口腔卫生服务的态度评价 ,有助于口腔卫生服务体系的制定和评价。方法 :根据武汉市卫生部门登记在册的牙科医生 ,采用整群抽样的方法随机选择 2 5 0名牙科医生进行开放式问卷调查。结果 :所调查的 2 5 0名样本中 ,5 2 %为女性 ,牙科医生平均工作年限为 11.6年 ,平均使用 0 .8台牙椅 ,每位牙医平均每天看 15个病人。主要工作时间用于充填治疗和拔牙。 93 %的牙医认为中国口腔卫生服务强调治疗而忽视预防保健。结论 :口腔卫生服务应重视口腔预防保健  相似文献   
40.
Sympathetic nervous control of cat ileocecal sphincter   总被引:1,自引:0,他引:1  
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