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81.
Contrafouris CA Giannopoulos NM Chatzis AC Antoniades A Zavaropoulos PN Kirvassilis GV Kremastinos DT Sarris GE 《Journal of cardiac surgery》2005,20(5):460-462
Anomalous origin of the left coronary from the pulmonary artery (ALCAPA) is a rare congenital malformation, which may result in myocardial infarction, congestive heart failure, and sudden death if left untreated. Despite frequently advanced pathologic changes, there seems to be significant potential for the recovery of myocardial function in individuals with left ventricular dysfunction after the establishment of physiologic coronary circulation, particularly in the pediatric population. Reports of ALCAPA repair in adulthood are scarce and little information exists regarding the response of the left ventricle to revascularization in this age group. In this report, repair of ALCAPA in a significantly symptomatic adult patient with ventricular dysfunction is described, leading to an early recovery of left ventricular function. 相似文献
82.
Cho AK Sioutas C Miguel AH Kumagai Y Schmitz DA Singh M Eiguren-Fernandez A Froines JR 《Environmental research》2005,99(1):40-47
Epidemiologic studies have shown associations between ambient particulate matter (PM) and adverse health outcomes including increased mortality, emergency room visits, and time lost from school and work. The mechanisms of PM-related health effects are still incompletely understood, but a hypothesis under investigation is that many of the adverse health effects may derive from oxidative stress, initiated by the formation of reactive oxygen species (ROS) within affected cells. While the adverse effects from PM have historically been associated with the airborne concentration of PM and more recently fine-particle PM, we considered it relevant to develop an assay to quantitatively measure the ability of PM to catalyze ROS generation as the initial step in the induction of oxidative stress. This ability of PM could then be related to different sources, chemical composition, and physical and spatial/temporal characteristics in the ambient environment. The measurement of ROS-forming ability in relation to sources and other factors will have potential relevance to control of redox-active PM. If oxidative stress represents a relevant mechanism of toxicity from PM, the measurement of redox activity represents a first step in the elucidation of the subsequent downstream processes. We have developed an assay for PM redox activity, utilizing the reduction of oxygen by dithiothreitol which serves as an electron source. We have found that PM will catalyze the reduction of oxygen and have examined the distribution and chemical characteristics of the redox activity of PM fractions collected in different sites in the Los Angeles Basin. Samples of concentrated coarse, fine, and ultrafine PM, obtained with aerosol concentrators, were studied with regard to their chemical properties and redox activity. Redox activity was highest in the ultrafine fraction, in agreement with results indicating ultrafines were the most potent toward inducing that heme oxygenase expression and depleting intracellular glutathione, which has relevance to induction of oxidative stress. Comparison of the redox activity with chemical composition showed a reasonable correlation of redox activity with elemental carbon (r(2)=0.79), organic carbon (r(2)=0.53), and with benzo[ghi]perylene (r(2)=0.82), consistent with species typically found in mobile emission sources. 相似文献
83.
Bouzas EA Karadimas P Kanaka-Gantenbein C Papastathopoulos C Dimitrakos S Mastorakos G 《Journal of pediatric ophthalmology and strabismus》2005,42(1):47-51
We describe the ophthalmologic findings in two cases of cerebrofaciothoracic dysplasia, a rare syndrome characterized by facial dysmorphism, multiple malformations of the vertebrae and ribs, and significant mental retardation. Both affected individuals are members of the same family and have epicanthal folds and hypertelorism. In addition, one patient has bilateral bull's eye maculopathy, which may represent an additional severe manifestation of cerebrofaciothoracic dysplasia syndrome. 相似文献
84.
Gardikis S Danielides V Tsalkidis A Vaos G Chatzimicael A Simopoulos C 《Acta paediatrica (Oslo, Norway : 1992)》2005,94(5):629-631
Here we present the first reported case of an ingested open safety-pin in a 7-mo-old boy that migrated from the stomach to the oesophagus. CONCLUSION: This rare complication is probably due to a gastro-oesophageal reflux effect, and for this reason we propose that all infants with safety-pins and other sharp objects in the stomach should be positioned in a semi-upright position. 相似文献
85.
Data are scarce relating to the plasticity with strength training of dynamic muscle performance in older humans. Hence, we investigated alterations in the torque-velocity relation with strength training in old age, and their origin. Knee extension and leg-press exercises were performed three times per week for 14 weeks. Maximal isokinetic knee extension torque was assessed during concentric and eccentric muscle actions. Agonist-antagonist muscle activation was assessed using electromyography. Vastus lateralis muscle architecture was examined in vivo using ultrasonography. Training increased concentric torque by 22-37% (P < 0.01), but failed to alter eccentric torque (P > 0.05). Increased agonist muscle activation, increased muscle fascicle lengths, and greater elastic energy recovered from tendinous structures may explain the adaptations during concentric actions, whereas the failure of eccentric torque to increase might be explained by the preservation of eccentric force with aging and an underloading of the eccentric movement phase during training. These findings may have important implications for dynamic muscle performance in old age. 相似文献
86.
Christodoulakos G Lambrinoudaki I Panoulis C Papadias C Economou E Creatsas G 《Fertility and sterility》2004,82(3):634-638
OBJECTIVE: To investigate the effect of continuous combined hormone therapy and raloxifene on serum VE-cadherin. DESIGN: The study was double blinded, with a placebo run-in period of 28-50 days. SETTING: University menopause clinic. PATIENT(S): Twenty-eight healthy postmenopausal women devoid of climacteric complaints. INTERVENTION(S): Subjects were randomized to 17beta-estradiol (2 mg) + norethisterone acetate (1 mg; E(2)-NETA) or raloxifene hCL (60 mg) for a period of 6 months. MAIN OUTCOME MEASURE(S): Serum VE-cadherin, which was estimated at baseline and at month 6. RESULT(S): Serum VE-cadherin decreased significantly in both E(2)-NETA and raloxifene groups (raloxifene baseline +/- SD: 1.17 +/- 0.44 ng/mL, 6 months: 0.82 +/- 0.29 ng/mL; E(2)-NETA baseline: 1.19 +/- 0.47 ng/mL, 6 months: 0.92 +/- 0.49 ng/mL). Percentage changes from baseline were -21.7 +/- 24.3 for E(2)-NETA and -26.0 +/- 20.6 for raloxifene. CONCLUSION(S): The effect of E(2)-NETA and raloxifene suggests that these drugs may preserve interendothelial junction integrity and control vascular permeability. Although this effect may influence the progress of the atheromatous lesion, its clinical impact on coronary artery disease (CAD) remains uncertain. 相似文献
87.
Biomechanics and pathophysiology of overuse tendon injuries: ideas on insertional tendinopathy 总被引:2,自引:0,他引:2
Maganaris CN Narici MV Almekinders LC Maffulli N 《Sports medicine (Auckland, N.Z.)》2004,34(14):1005-1017
Tendons behave viscoelastically and exhibit adaptive responses to conditions of increased loading and disuse. High-resolution, real-time ultrasound scanning confirms the applicability of these findings in human tendons in vivo. In addition, recent biomechanical studies indicate that strain patterns in tendons may not be uniform, as tendons show stress-shielded areas and areas subjected to compressive loading at the enthesis. These areas correspond to the sites where tendinopathic characteristics are typically seen. This indicates that some tendinopathies may, paradoxically, be considered as 'underuse' lesions despite the common beliefs that they are overuse injuries. Classic inflammatory changes are not frequently seen in chronic athletic tendon conditions and histopathology features in tendinopathic tendons are clearly different from normal tendons, showing an exaggerated dysfunctional repair response. Tendinopathies are traditionally considered overuse injuries, involving excessive tensile loading and subsequent breakdown of the loaded tendon. Biomechanical studies show that the strains within the tendons near their insertion site are not uniform. If the material properties are similar throughout the tendon, forces transferred through the insertion site preferentially load the side of the tendon that is usually not affected initially in tendinopathy. In that case, the side affected by tendinopathy is generally 'stress shielded'. Thus, the presence of differential strains opens the possibility of alternative biomechanical explanations for the pathology found in these regions of the tendon. The traditional concept of tensile failure may not be the essential feature of the pathomechanics of insertional tendinopathy. Certain joint positions are more likely to stress the area of the tendon commonly affected by tendinopathy. Incorporating different joint position exercises may exert more controlled stresses on these affected areas of the tendon, possibly allowing better maintenance of the mechanical strength of that tendon region and, therefore, prevent injury. Such exercises could stress a healing area of the tendon in a controlled manner and thus stimulate healing once an injury has occurred. Additional work is needed to prove whether such principles should be incorporated in current rehabilitation techniques. 相似文献
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