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Objectives: The purpose of this study was to determine if a device placed externally around the aortic root decreases regurgitant flow in acute aortic regurgitation. Background: Aortic regurgitant flow is dependent on central aortic pressure and the aortic root and leaflet geometry. It may be possible to decrease aortic regurgitant severity by reducing aortic root size or dimension changes. Methods: Aortic regurgitation was created in eight calf heart specimens suspended in a continuous flow system. Retrograde and antegrade aortic flow and distending aortic pressure were measured at baseline and after placement of an external aortic device at the level of the aortic annulus. In two additional specimens, the incompetent aortic valve was visualized fiberoptically before and after placement of the external device. Acute aortic regurgitation was created surgically in four live calves by excising a portion of the aortic leaflets. Antegrade and retrograde flow, left ventricular pressure, and central aortic pressure were measured at baseline, after creation of aortic regurgitation, and after placement of the external device. Results: In the in vitro calf specimens, regurgitant flow decreased from 46.9 cc/sec to 15.1 cc/sec (66.0%± 21.8% decrease) after placement of the external device (p < 0.001). The regurgitant orifice area decreased from 0.13 ± 0.04 cm2 to 0.04 ± 0.02 cm2 after device placement (p < 0.001). Antegrade flow was reduced to a smaller extent (20.0%± 19.2% decrease) by the device (p < 0.05). Placement of the device around the aorta resulted in improved coaptation of the leaflets with a marked reduction in defect size by endoscopic visualization. Use of the external aortic device was associated with improvement in aortic regurgitant severity in three of four calves with surgically created aortic regurgitation. Concluslons: In these preliminary studies, acute experimental aortic regurgitant severity is decreased by the use of an external aortic device, probably due to reduction in aortic annular dimension changes and improved aortic leaflet apposition. Further studies are needed to determine the effectiveness of this device in chronic aortic regurgitation. (J Card Surg 1994;9:304–313)  相似文献   
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OBJECTIVE: The prevalence of child psychiatric morbidity in the community is unknown in most developing countries, including those in the Arab region. METHOD: An epidemiologic study was carried out to estimate the prevalence of psychiatric morbidity and to determine the sociodemographic correlates in a sample of children in the community, aged 6 to 18 years, in A1 Ain, United Arab Emirates (UAE). RESULTS: We obtained a prevalence rate of 22.2% for overall morbidity, as classified in the DSM-1V, and 14.3% for those with significant dysfunction, with the most common diagnosis being mood disorders. Female sex, large family size, chronic life difficulties, family history of psychiatric disorder, and alcohol-related problems in a family member were significantly associated with DSM-IV diagnosis. CONCLUSION: Although the prevalence and symptomatology in this Middle East community are similar to those in Western studies, none of these children had received professional help, suggesting serious deficiencies in mental health care services in the country.  相似文献   
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A bstract The right gastroepiploic artery (RGEA) has been utilized as the bypass conduit on the inferior surface of the heart with a minimally invasive approach. Fourteen patients had reoperative coronary bypass surgery for severely symptomatic single-vessel disease of the right coronary artery. All surgeries were performed since May 1996. A small mid-line incision including splitting of the lower sternum gave excellent exposure. The inferior surface of the heart was dissected to expose and stabilize the target vessel. The heart rate was controlled with a diltiazem drip. Cardiopulmonary bypass was not necessary in any case. The right coronary artery was bypassed in three patients, the posterior descending artery branch in ten patients, and the terminal circumflex of the left coronary artery in one. After grafting, patency of the anastomosis was demonstrated by Doppler echocardiogram. Two patients had left anterior descending artery (LAD) grafts with LIMA (left mammary artery) and RGEA grafts performed simultaneously with two port access incisions. No patient had perioperative mortality or complications. No patient had recurrent angina. Doppler color echocardiographic imaging studies before discharge confirmed patency of the graft in 13 of 14 cases. In one case, the gastroepiploic artery could not be visualized. Angiographic visualization was positive in seven cases; seven patients were not studied yet. The gastroepiploic artery is an excellent conduit for vascularization of the inferior aspect of the heart. The operation can be done with a minimally invasive technique and without the use of cardiopulmonary bypass. This approach seems especially applicable in selective reoperative cases.  相似文献   
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This study investigated relationships between child/parent dissatisfaction with child facial appearance and the self-concept/social competence of 8- to 15-year-old children with (N = 34) and without (N = 34) oral clefts. Children in both groups had normative psychosocial adjustment, but also reported moderate dissatisfaction with facial appearance. Cleft group parents were more likely to agree with their child's dissatisfaction. When cleft group parents were more dissatisfied with child facial appearance, their children reported better quality of life. Results suggest that parents of children with clefts reporting greater dissatisfaction may respond in positive ways that enhance quality of life.  相似文献   
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OBJECTIVE: To determine if differences in balance and recovery would be found between controls and participants with unilateral or bilateral functional ankle instability (FAI). DESIGN: Cross-Sectional Study. SETTING: University laboratory and Community premises. PARTICIPANTS: Twenty healthy participants(C), 19 participants with unilateral FAI [both the uninjured (UC) and unstable ankle (UI) were included] and 22 participants with bilateral FAI (BI). MAIN OUTCOME MEASURES: Balance was measured in single leg stance as: number of part foot lifts in 30 s; magnitude of medio-lateral ankle movement in two foot positions; and ability to balance on the ball of the foot. Recovery was determined by time to return to baseline medio-lateral ankle movement after a 15 degree inversion perturbation. RESULTS: The controls lifted the foot fewer times than the other three groups [C = 12.7 +/- 1.8 (mean +/- SE) foot lifts, UC = 22.9 +/- 2.5, UI = 25.1 +/- 2.3, and BI = 21.1 +/- 2.2, t-test, P = 0.006] and recovered significantly faster than the unstable ankles [C = 1.53 +/- 0.42 sec (median +/- SE), UI = 2.34 +/- 0.30 sec, BI = 2.15 +/- 0.70 sec, P < 0.02]. With FAI measured by the Cumberland Ankle Instability Tool, the external control group balanced on demi-pointe better than both instability groups (P < 0.05), and recovered quicker than all groups. CONCLUSION: There are differences in balance and recovery between external controls and participants with both unilateral and bilateral FAI but not between the legs of participants with unilateral FAI.  相似文献   
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