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BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
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镉对肾脏的毒作用   总被引:6,自引:0,他引:6  
雄性Wistar大鼠24只,随机等分为4组,皮下注射不同剂量的CdMT。结果显示镉接触组尿钙和尿蛋白都高于对照组;肾皮质钠泵和钙泵活性低于对照组,体外试验也显示镉能抑制钙泵活性,GSH和半胱氨酸对这种抑制有保护作用;肾皮质GSH含量低于对照组,MDA含量则高于对照组,但肝脏的这两个指标无变化;高剂量组cAMP/cGMP的比值低于对照组。提示脂质过氧化和钙代谢障碍是镉引起肾损害的机理之一。  相似文献   
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A randomized controlled trial of sedation in the critically ill   总被引:2,自引:0,他引:2  
A randomized controlled trial comparing: a) a combination of oral chloral hydrate and promethazine to b) a continuous intravenous midazolam infusion, for maintenance sedation in critically ill children, was carried out. The level of sedation was assessed four hourly using a specifically devized sedation scale. Forty-four children entered the study of whom two were subsequently excluded. The number of satisfactory assessments (desired and actual levels of sedation equal) was significantly greater in the chloral hydrate and promethazine group (Chi-squared P <0.01; confidence intervals of the difference 0.06 to 0.20). The number of assessments at level 5 on the sedation scale (patient restless/distressed) was significantly greater in the midazolam group (Chi-squared P <0.05). The total number of satisfactory assessments in the two groups were only 61 and 48% respectively, suggesting that sedation can be considerably improved. Chloral hydrate and promethazine are more effective than midazolam as maintenance sedation in critically ill children. It is possible to prospectively study the efficacy of sedative drugs in critically ill children.  相似文献   
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The computerized database system described was initially developed in 1986 to facilitate analysis of retrospective head and neck cancer data from the Royal Adelaide Hospital Department of Otolaryngology. This has now been expanded to become an on-going patient information management system. It is based on the dBase-III-Plus database package and is implemented on an IBM XT compatible computer. The system was designed to be used by staff without specialist computer skills and is therefore largely “menu-driven.” The main functions include patient record creation, update, and retrieval, and the production of reports including graphical presentations. There is also a powerful but easy to use query facility. The system has already provided much useful epidemiological material but is now beginning to fulfill an even more important role in patient follow-up and in assisting evaluation of alternative treatment protocols.  相似文献   
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Background

In Uganda the prevalence of HIV averages 12% as was reported to the STD/AIDS control surveillance unit. In Uganda there are approximately 30,000 HIV infected infants per year. The burden of HIV disease is high in Uganda and patients present with ocular complications. However, there is paucity of information and knowledge concerning ocular manifestations in the paediatric HIV/AIDS population and how they may differ from those of adults.

Objectives

To describe the ocular manifestations of HIV/AIDS infection in an African paediatric population. Generally the study will record the external ocular manifestations seen but specifically to document the intra-ocular lesions, in particular the retinal changes associated with paediatric HIV/AIDS.

Design

A cross-sectional hospital based study.

Setting

The study was conducted at the Paediatric Infectious Disease Clinic at Upper Mulago Hospital, in Kampala, Uganda.

Patients

Patients are those with positive HIV sero status, with or without symptoms and signs of AIDS.Parents/caretakers of the children were interviewed to obtain the socio-demographic data of the patients and a general physical as well as an ophthalmic examination were conducted to document any ocular problems.

Results

A total of 158 HIV -infected children were examined. The overall rate of ophthalmic involvement was 35%. The most common finding was a non-purulent conjuctivitis, observed in 12% of the patients, followed by perivasculitis of the peripheral retinal vessels, in 12 % of patients and molluscum contagiosum.  相似文献   
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