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Heart transplantation is a recognised treatment for end-stage heart failure of any cause including congenital heart disease. Congenital heart disease has contributed relatively little to the adult heart transplant activities in the past two decades. However, this is likely to change as an increasing number of children with congenital heart disease reach adulthood because of the advances in paediatric cardiology and surgery. Some of these grown-ups with congenital heart disease (GUCH patients) will need transplantation for late myocardial dysfunction either secondary to uncorrected lesions, or despite previous repair or palliative surgery. These patients are managed along the same clinical principles as those with cardiac failure of other aetiologies, despite the lack of any evidence to support this approach. Nevertheless, they introduce new challenges. First, some may have pulmonary vascular disease and require heart-lung transplantation, or lung transplantation combined with repair of their cardiac defects. Second, those with failing Fontan circulation are usually much sicker than other transplant candidates, with protein-losing enteropathy along with renal and hepatic dysfunction. Third, a suitable donor organ may not be found due to elevated levels of antibodies in response to previous blood transfusions and possibly the previous implantation of homografts. Fourth, the operation may be technically difficult because of the presence of adhesions secondary to previous operations, collaterals, and unusual anatomy. Fifth, postoperative care may be complicated because of predisposition to bleeding, infection and pulmonary hypertension, and the presence of residual aortopulmonary collaterals resulting in a significant left-to-right shunt. Despite a higher early mortality, the overall results of heart transplantation so far have been encouraging with survivals similar to that of adults with acquired heart disease and that of the paediatric population. However, this may change as the proportion of high-risk patients (failing Fontans) increases. GUCH patients with Eisenmenger's syndrome may be offered lung transplantation with repair of the cardiac defect or heart-lung transplantation. However, because of the limited success of these approaches, and improved management of pulmonary hypertension, patient selection remains difficult.  相似文献   
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An effective treatment of comminuted fractures of the distal radius   总被引:2,自引:0,他引:2  
One hundred cases of comminuted fracture of the distal radius were treated by a simple uniform method consisting of distraction by an external fixator for 3 weeks followed by functional bracing. During the application of the external fixator, autogenous cancellous bone chips were taken from the iliac crest and packed into the fracture site to realign the juxtaarticular fragments and to fill up the bone gap. Complications have been minimal. The results, after an average follow-up period of 20 months, taking into consideration subjective assessment of pain, objective measurement of wrist motion, and radiologic angles, have been excellent.  相似文献   
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Surgical Management of Marfan Syndrome in Children   总被引:1,自引:0,他引:1  
Between August 1983 and January 1991, seven patients with Marfan syndrome underwent surgery for severe cardiovascular complications. The mean age at presentation was 5.7 months (range 4 to 9 months) in the infant group (n = 3), and 13.3 years (range 10 to 16 years) in a group of older children (n = 4). The primary indications for surgery in the infant group (performed at a mean of 3 years after diagnosis) were ascending aortic aneurysm with valvar regurgitation in one patient, and severe mitral valve prolapse with regurgitation in two. In the older group, surgical indications (performed at a mean of 2.8 years after diagnosis) were ascending aortic aneurysm with valvar regurgitation in three patients and acute aortic dissection in one. For aortic surgery, a composite valved conduit was used in four patients, and an aortic homograft in one. For mitral valve surgery, mechanical prostheses were used. Ail patients survived the primary operation. Over a mean follow-up of 17.5 patient-years (range 1 to 9 years), two patients in the infant Marfan group went on to further successful surgery (prosthetic mitral valve replacement and aortic root repair with aortic homograft) at a mean interval of 4.3 years after the Initial surgery. Our results suggest that the major cardiovascular risk factors of Marfan syndrome in the young, even in those diagnosed during infancy, have been favorably changed by surgery with an encouraging medium-term outlook. The correct timing of surgery is aided by echocardiography. (J Card Surg 1994;9:50–54)  相似文献   
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In a 3-year period, 63 consecutive patients with advanced perforated (n=53) and gangrenous (n=10) appendicitis were allocated to undergo either immediate wound closure or delayed primary wound closure after emergency appendectomy. The incidence of wound infection between delayed primary wound closure and immediate wound closure was similar (24.0% and 21.1%, respectively). The duration for complete healing of infected wounds was slightly shorter in the group undergoing delayed primary wound closure (mean +/- SD, 24.3 +/- 9.2 days) than in the group undergoing immediate wound closure (mean +/- SD, 32.6 +/- 16.5 days), but the difference was not significant. However, healing of noninfected wounds was significantly prolonged in the group undergoing delayed primary wound closure (mean +/- SD, 19.3 +/- 10.1 days) compared with the group undergoing immediate wound closure (mean +/- SD, 7.0 +/- 0 days). The latter had been shown to associate with more nonseptic wound complications and therefore required longer rehabilitation. Our study showed that delayed primary closure did not offer additional advantage over immediate closure in the treatment of wounds associated with advanced appendicitis in children.  相似文献   
16.
A study was undertaken to examine the potential role of immunodiagnostic methods in determining successful chemotherapy in schistosomiasis. Fifteen rhesus monkeys were infected with 1,500 Schistosoma mansoni (Puerto Rico strain) cercariae, and 10 of the monkeys were then treated with a curative dose of praziquantel 13 weeks after infection. Five monkeys remained untreated. One monkey was not successfully cured, as confirmed by the presence of both male and female worms at the time of perfusion. Serum samples were longitudinally collected and specific Ig isotypes were quantified with an adult microsomal antigen of S. mansoni using the FAST-ELISA. Specific isotypes were detected with monoclonal antibodies specific for each human Ig isotype, followed by a peroxidase-conjugated anti-mouse Ig. Longitudinally, all monkeys showed similar isotype patterns. Isotypes increased for the first nine weeks following infection, and then began to decrease. Ten to 14 days following treatment, all isotypes increased. The Ig isotype responses of all monkeys followed classic patterns of isotype expression. A ratio of pretreatment (week 13) IgG1 absorbance values to post-treatment IgG1 absorbance values was generated for each monkey. All successfully treated monkeys, determined to be worm-free by perfusion, had IgG1 ratios at week 53 greater than 2.4 (range 2.4-181). The untreated monkeys and the single monkey that was a treatment failure had IgG1 ratios less than 2.1 (range 0.09-2.05) for the same time period.  相似文献   
17.
亮氨酸脑啡肽的电子结构及构效关系研究   总被引:1,自引:0,他引:1  
对亮氨酸脑啡肽进行了量子化学(INDO)计算,研究其电子结构特征,讨论其活性部位、作用机理及构效关系。同吗啡和R31833进行了活性部位的电子结构与空间结构比较,推断它们的活性药效结构具有共同特点,与阿片受体相互作用时作用方式相同,作用部位有对应关系,因而具有相同的药理性质。  相似文献   
18.
Summary: Purpose: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellin, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. Methods: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. Results: Prevalence of neurocys@ercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellin. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. Conclusions: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.  相似文献   
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