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51.
Adrian Ooi Narain Moorjani Giedrius Baliulis Barry R. Keeton Anthony P. Salmon James L. Monro Marcus P. Haw 《European journal of cardio-thoracic surgery》2006,30(6):917-922
Objective: To assess the impact of early corrective surgery on the short and medium term outcome in tetralogy of Fallot (TOF). Materials and methods: All patients under 12 months of age undergoing correction of isolated TOF between February 1997 and July 2003 were reviewed retrospectively. Outcome data for mortality, post-operative care management, major morbidity and clinical follow-up were analysed. Results: Fifty-two operations were performed. The mean age at surgery was 5 months (range 1–12) of whom 16 (30.8%) were less than 3 months old, including 2 neonates, 22 (42.3%) were 3–6 months old and 14 (26.9%) were 7–12 months old. There was 1 (1.9%) early death caused by a cerebro-vascular accident and 1 (1.9%) late death secondary to acute infective endocarditis. There were no differences in post-operative morbidities attributable to age. Patients under 3 months old required greater duration of post-operative ventilation, ITU stay and in-hospital stay. At a mean follow-up of 4.0 years (range 1.5–8.0), 33 (63.5%) patients had well-tolerated pulmonary regurgitation (PR) and 3 (5.8%) patients required re-operation for right ventricular outflow tract obstruction (RVOTO). All patients had right bundle-branch-block but with QRS < 150 ms. Conclusion: Early definitive repair of TOF can be performed safely on patients under 6 months old. Age at surgery does not appear to affect the medium term haemodynamic outcome. However, early surgery does escalate the need for ICU care. This data suggests repair in asymptomatic patients be delayed until 3–6 months of age. 相似文献
52.
Zhenlin Li Emma Colucci Charles Babinet Denise Paulin 《Neuromuscular disorders : NMD》1993,3(5-6):423-427
Desmin synthesis is restricted to cardiac, skeletal and smooth muscles. In several familial myopathies involving fibre disorganization, filamentous aggregation of desmin has been characterized. During the development of the mouse embryo, desmin is one of the first muscle proteins detected in both the heart and the somites. To identify the DNA sequences involved in the regulation of desmin gene expression a 4.5 kb 5′-flanking region of the human desmin gene has been isolated. Different mutants were used to characterize specific enhancers in vitro and in vivo. The results obtained with transgenic mice provide evidence that the 1 kb cis-regulatory sequences, functional in skeletal muscle cells in vitro, confer specific developmental control for skeletal muscles. Furthermore, distinct programmes for cardiac and skeletal muscle-specific expression of the desmin gene are revealed. 相似文献
53.
Susan Redline Emma K Larkin Carolyn Kercsmar Melvin Berger Laura A Siminoff 《Annals of allergy, asthma & immunology》2003,90(5):516-528
BACKGROUND: The increasing morbidity attributable to asthma among school-aged children suggests the potential utility of school-based asthma screening programs. OBJECTIVE: We report our efforts to develop and validate culturally sensitive and clinically useful screening questionnaires (parent and child versions) for asthma and allergies among urban US school children. METHODS: Instrument development was accomplished through literature review, expert medical and child developmental input, focus group feedback, and a rigorous trial of the instruments in a public school setting. Questionnaires were distributed to 2,800 children and their families in an urban public school system (grades kindergarten through 6). Validity was evaluated by blinded comparison of results against a standardized clinical evaluation in 107 children, with final designations determined by an expert panel. RESULTS: Questionnaires pertaining to 2,083 children were returned (participation rate of 74%). A moderate level of agreement was observed between parent and student questionnaire responses (r values = 0.36 to 0.50; P values < 0.001). The highest frequency of asthma-like symptoms was reported for African-American boys and the lowest for Caucasian girls. The items from the parent questionnaire that best predicted asthma were "breathing problems" (occurring rarely or more; odds ratio 12.8; 95% confidence interval, 4.5 to 36.1) and "problems coughing" (sometimes or more; odds ratio 9.7; 95% confidence interval, 3.6 to 26.5). Considering the presence of cough (sometimes or more) and/or breathing problem (rarely or more) yielded a sensitivity of 80%; a specificity of 75%, a positive predictive value of 50%, and a negative predictive value of 92%. Similar levels of prediction were observed for the items "trouble breathing" and "noisy breathing" as directly reported by the students. Allergic rhinitis was best predicted by report of a runny/stuffy no se (sometimes or more; sensitivity of 83%, specificity of 61%).Allergic conjunctivitis was best predicted by "itchy eyes." CONCLUSIONS: Administration of a school-based questionnaire is feasible, with a high response rate and excellent internal consistency. A high sensitivity and acceptable specificity was achieved by using one to two questions for asthma, allergic rhinitis, and allergic conjunctivitis. Among the children in grades 2 or above, comparable levels of prediction could be achieved with the student or parent version. 相似文献
54.
Juan Tentoni Nélida Nora Polini Emma Beatriz Casanave 《Comparative clinical pathology》2008,17(3):193-196
The fibrinolytic mechanism in the armadillo Chaetophractus villosus (Mammalia, Xenarthra, Dasypodidae) quite unknown until now was studied. Results were compared with those corresponding to
healthy adult human beings. Whole blood lysis time and diluted blood lysis time were not detectable in armadillos. Euglobulin
clot lysis time and plasminogen activity (Plg) were lower than in healthy humans. We established the presence of the fibrinolytic
system in Ch. villosus through the measurement of fibrin fibrinogen degradation products. The activity of the plasminogen activator inhibitor was
two to four times greater than in healthy humans. The activity of the alpha 2 anti-plasmin (α2AP) was similar and displaced
toward lower values. The Plg/α2AP relation was lower. The results obtained suggest that Ch. villosus has a hypercoagulable and hypofibrinolytic profile. Our findings are not only the first contribution to elucidate the physiology
of the fibrinolytic system in Xenarthra but also contribute to develop an animal model for studies in haemostasis and thrombosis. 相似文献
55.
Palmieri EA Palmieri V Innelli P Arezzi E Ferrara LA Celentano A Fazio S 《European journal of applied physiology》2005,94(1-2):113-117
In older healthy men, aerobic exercise capacity is related to postischemic flow-mediated dilation of the brachial artery (FMD), but corresponding data in a younger population is not available. In addition, whether submaximal aerobic exercise performance also correlates with this kind of vasomotor reactivity is not known. Therefore, in 15 nonsmoking young healthy men [age 27 (5) years; body mass index: 24 (2) kg/m2; mean (SD)] with different levels of ordinary physical activity, but not performing upper-extremity training, we measured FMD at 1 min after reactive hyperemia, and pulmonary oxygen uptake (O2) at ventilatory anaerobic threshold (O2AT) and at peak effort (peak O2) during an incremental exercise on a treadmill. In our participants, FMD was 9.1 (3.4)%, O2AT was 40.72 (5.92) ml/kg per min, and peak O2 was 52.95 (8.13) ml/kg per min. Using bivariate Pearsons correlation, and in separate multivariate regression analyses, O2AT and peak VO2 showed a significant and reasonably good correlation with FMD (r=0.84, P<0.001 and r=0.77, P=0.001, respectively), independent of age, body mass index and serum total cholesterol (=0.77, P<0.001, R2 of the overall model=0.79 and =0.70, P<0.005, R2 of the overall model=0.69, respectively). Our data provide evidence suggesting that in young healthy men a higher submaximal and maximal aerobic exercise performance is associated with a greater FMD of peripheral conduit arteries. 相似文献
56.
The murine NF2 homologue encodes a highly conserved merlin protein with alternative forms 总被引:4,自引:1,他引:4
Haase Volker H.; Trofatter James A.; MacCollin Mla; Tarttelln Emma; Gusella James F.; Ramesh Vijaya 《Human molecular genetics》1994,3(3):407-411
The recently isolated gene for neuroflbromatosls type 2 (NF2)encodes a 595 amlno acid protein, named merlin, which Is relatedto the cytoskeleton-assoclated proteins moesln, ezrin and radlxin.To Identify evolutionarily conserved regions and to providesequence Information necessary for the establishment of a mousemodel for NF2, we have determined the cDNA sequence of the mouseNF2 tumor suppressor gene, and mapped It In the mouse genome.Mouse merlin is a 596 amino acid protein, 98% identical to humanmerlin, but one amlno acid longer due to the Insertion of aproline residue near the C-terminus. Of the nine amlno aciddifferences between mouse and humans, seven occur in the C-termlnal20% of the protein, far from the protein 4. 1 domain that definesthis family. Two of the NF2 cDNA clones reveal evidence of alternativesplicing events that alter the predicted merlin product, oneremoving a 45 amlno acid segment from the middle section ofthe protein and the other changing the C-terminus. The existenceof several different forms of merlin potentially with differentprimary roles will complicate the Identification of the precisefunction that must be disrupted to cause the NF2-assoclatedtumors. The mouse NF2 homologue maps to Chr 11, in a regionhomologous to human Chr 22, but devoid of any mouse mutationswhich could be models of the human disorder. 相似文献
57.
Development of a Western Blot Assay for Detection of Antibodies against Coronavirus Causing Severe Acute Respiratory Syndrome
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Qigai He Kooi Hoong Chong Hiok Hee Chng Bernard Leung Ai Ee Ling Ting Wei Shzu-Wei Chan Eng Eong Ooi Jimmy Kwang 《Clinical and Vaccine Immunology : CVI》2004,11(2):417-422
To identify a major antigenic determinant for use in the development of a rapid serological diagnostic test for severe acute respiratory syndrome (SARS) coronavirus infection and to study the immune response during SARS coronavirus infection in humans, we cloned the full length and six truncated fragments of the nucleocapsid gene, expressed them, and purified them as glutathione S-transferase-tagged recombinant proteins. The reactivities of the recombinant proteins to a panel of antibodies containing 33 SARS coronavirus-positive sera and 66 negative sera and to antibodies against other animal coronaviruses were screened. A truncated 195-amino-acid fragment from the C terminus of the nucleocapsid protein (N195) was identified that had a strong ability to detect antibodies against SARS coronavirus. No cross-reaction was found between the N195 protein and antibodies against chicken, pig, and canine coronaviruses. The N195 protein was used to develop a Western blot assay to detect antibodies against SARS coronavirus in 274 clinically blinded samples. The specificity and sensitivity of this test were 98.3 and 90.9%, respectively. The correlation between our Western blotting assay and an immunofluorescence assay (IFA) was also analyzed. The results of our Western blot assay and IFA for the detection of SARS coronavirus-positive sera were the same. Thus, the N195 protein was identified as a suitable protein to be used as an antigen in Western blot and other possible assays for the detection of SARS coronavirus infection. 相似文献
58.
B S Ooi K S Kant I B Hanenson A J Pesce V E Pollak 《Clinical and experimental immunology》1977,30(1):56-61
The present study was undertaken to determine the prevalence and nature of lymphocytotoxic antibodies in patients receiving phenytoin. Of forty-six sera examined, lymphocytotoxins and antinuclear antibodies were detected in fourteen and eleven samples respectively. Antibodies to double-stranded RNA (poly-A-poly-U) were found in six out of thirty-eight sera studied. A highly significant correlation was found between the presence of lymphocytotoxins and antinuclear antibodies (chi2 = 9.72; P less than 0.01). Lymphocytotoxins were found to be of the IgM class, to have activity against T and B cells, and to be dependent on the presence of Ca and Mg ions for activity. These findings may have pathogenetic importance in the genesis of the altered immune state of patients reveiving phenytoin. 相似文献
59.
Janine M Prince Teresa C M Klinowska Emma Marshman Emma T Lowe Ulrike Mayer Jeff Miner Daniel Aberdam Dietmar Vestweber Barry Gusterson Charles H Streuli 《Developmental dynamics》2002,223(4):497-516
Epithelial cell survival is dependent on extracellular signals provided by both soluble factors and by adhesion. In the mammary gland, extensive apoptosis of epithelial cells occurs rapidly when lactation ceases, but the mechanism of apoptosis induction is not known. In tissue culture, mammary epithelial cells require laminin as a survival ligand and specific beta1 integrins are necessary to suppress apoptosis. To explore the possibility that dynamic changes in cell-matrix interactions contribute to the onset of apoptosis during mammary involution in vivo, a detailed immunohistochemical analysis of the expression of integrin subunits and their extracellular matrix ligands during mouse mammary gland development has been performed. The kinetics of apoptosis were determined by using tissue samples obtained from virgin, pregnant, lactating, and involuting gland. The maximal elevation of apoptosis occurred within 24 hr of weaning as determined by histologic analysis and caspase-3 staining. A wide variety of laminin subunits, together with nidogen-1 and -2, and perlecan were identified within the basement membrane region of epithelial ducts, lobules, and alveoli in both human and mouse mammary gland. However, no change in the distribution of any of the basement membrane proteins or their cognate integrin receptors was observed during the transition from lactation to apoptosis. Instead, we discovered that altered ligand-binding conformation of the beta1 integrin to a nonbinding state coincided with the immediate onset of mammary apoptosis. This finding may provide a novel dynamic mechanism for inhibiting the transduction of extracellular matrix survival signals, thereby contributing to the onset of apoptosis in a developmental context in vivo. 相似文献
60.
Helen He Ester Del Duca Aisleen Diaz Hyun Je Kim Jesús Gay-Mimbrera Ning Zhang Jianni Wu Jessica Beaziz Yeriel Estrada James G. Krueger Ana B. Pavel Juan Ruano Emma Guttman-Yassky 《The Journal of allergy and clinical immunology》2021,147(4):1369-1380
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