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Chronic obstructive pulmonary disease (COPD), which affects approximately 14 million Americans, is the fourth leading cause of death in the United States and is responsible for an estimated US$6.5 billion in direct and indirect costs per year [1,2]. Its usual course is a slow deterioration of lung function and progressive breathlessness with activities. The age-adjusted death rate for COPD rose 71% from 1967 to 1987, and the 10 year mortality rate is about 50%. Bronchodilators form one of the mainstays of therapy in COPD patients. The judicious use of these agents increases airflow and reduces dyspnea in patients with COPD. Patients often experience a reduction in symptoms and improvement in their quality of life. There are several classes of bronchodilators available for the treatment of COPD, each with specific clinical benefits: anticholinergics, short-acting beta 2 agonists, combination anticholinergic and short-acting beta 2 agonist, long-acting beta 2 agonists and methylxanthines. This chapter reviews the use of an anticholinergic (ipratropium bromide) concomitantly with other bronchodilators, focusing on patients with COPD.  相似文献   
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Monozygotic 24-year-old twins presented with discordant ovarian function. One had had premature ovarian failure at the age of 14 years, whereas her sister had normal ovaries and three naturally conceived children. After unsuccessful egg-donation therapy, the sterile twin received a transplant of ovarian cortical tissue from her sister by means of a minilaparotomy. Within three months after transplantation, the recipient's cycles resumed and serum gonadotropin levels fell to the normal range. During the second cycle, she conceived, and her pregnancy progressed uneventfully. At 38 weeks' gestation, she delivered a healthy-appearing female infant.  相似文献   
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Genetic relationships between populations can be studied by comparing genotypic and allelic similarities. This investigation aims to demonstrate that selected autosomal microsatellite markers could be used to study the genetic structures of different populations living in northwest Venezuela, in Zulia State. Seven autosomal systems (CSF1PO, TPOX, TH01, vWA, D7S820, D13S317, and D5S818) were tested by PCR in a multiplex format on 688 different chromosomes from unrelated individuals living in Maracaibo, "Isla de Toas," and "San José de Heras," and from two Amerindian populations from the "Sierra de Perijá," Barí' and Yukpa. Allele frequencies, Hardy-Weinberg equilibria, genetic distances, phylogenetic trees, and ethnic admixtures were estimated. The study shows the existence of a clear genetic difference among these populations in accordance with their historic evolution. The populations of Maracaibo and "Isla de Toas" showed a triracial origin, with a large European contribution, followed by an Amerindian component and a small African component. The indigenous groups, Barí' and Yukpa, showed exclusively an Amerindian component, and "San José de Heras" showed only an African component. These results indicate that microsatellite markers are useful for molecular anthropology in a regional and worldwide context and provide important genetic information about contemporary populations of Venezuela.  相似文献   
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BACKGROUND: Antioxidant therapy is a new therapeutical approach for patients with Friedreich ataxia. AIMS: To assess the effectiveness of long-term idebenone treatment in Friedreich ataxia patients. METHODS: An open-labelled prospective study. Ten paediatric patients (age range 8-18 years) and 14 adults (age range 18-46 years) with genetic diagnosis of Friedreich ataxia were treated with idebenone (5-20mg/kg/day) for 3-5 years. Neurological evolution was evaluated using the International Cooperative Ataxia Rating Scale (ICARS), and cardiological outcomes using echocardiography. RESULTS: In paediatric patients, no significant differences were observed in ICARS scores and echocardiographic measurements when comparing baseline status and after 5 years of follow-up. Concerning adult cases, ICARS scores showed a significant increase in neurological dysfunctions during 3 years of therapy (Wilcoxon test, p=0.005), while echocardiographic measurements remained unchanged. CONCLUSIONS: Our results indicate that longer-term idebenone treatment prevented progression of cardiomyopathy in both paediatric and adult patients, whereas its stabilizing effect on neurological dysfunction was present only in the paediatric population, mainly before puberty. This suggests that the age at which idebenone treatment is initiated may be an important factor in the effectiveness of the therapy.  相似文献   
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