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Familial hypercholesterolaemia is a frequent, inherited, monogenic disorder, associated with accelerated development of atherosclerotic disease leading to coronary artery disease. Life expectancy of patients with familial hypercholesterolaemia is reduced by 15-30 years unless they are adequately treated with lipid-lowering therapy. Given the chronic nature of this disease, the selection of a therapeutic approach should be strongly based on its long-term safety and tolerability. The introduction of HMG-CoA reductase inhibitors has revolutionised the treatment of familial hypercholesterolaemia.Simvastatin 40-80 mg/day effectively reduces serum low density lipoprotein (LDL)-cholesterol levels. Furthermore, simvastatin reduces triglycerides and mildly raises high density lipoprotein-cholesterol levels. In addition to the hypolipidaemic effect, other potentially important effects, such as improvement of endothelial function and reduction of LDL oxidation and vascular inflammation, have been associated with HMG-CoA reductase inhibitor therapy. Simvastatin has also been shown to abolish the progression, and even facilitate the regression, of existing human atherosclerotic lesions.The good safety and tolerability profile of simvastatin is clearly highlighted by the low rate of therapy discontinuation observed in several population-based clinical trials. The most common adverse events leading to the discontinuation of therapy are gastrointestinal upset and headache. Asymptomatic elevations in liver transaminase levels and myopathy are uncommon.The overwhelming clinical evidence regarding the long-term use of HMG-CoA reductase inhibitor therapy in patients with familial hypercholesterolaemia together with the long-term safety data (particularly relating to simvastatin) provide support for the use of this drug as a first-line agent when pharmacological treatment is indicated. Early intervention with simvastatin treatment can be successfully implemented with favourable economic benefits.  相似文献   
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STUDY OBJECTIVE: To describe the prevalence and patterns of use of crack and cocaine hydrochloride among heroin users in Spain. To explore if the expansion of heroin smoking is accompanied by a similar phenomenon for cocaine. DESIGN: Cross sectional study in 1995. Face to face interviews using a structured questionnaire. SETTING: Three cities with different prevalences of heroin use by smoking: high (Seville), intermediate (Madrid), and low (Barcelona). PARTICIPANTS: 909 heroin users, 452 in treatment and 457 out of treatment. MAIN RESULTS: Last month prevalence of crack use was 62.3% in Seville, 19.4% in Madrid, and 7.7% in Barcelona. Most users in Madrid (86.5%) and Barcelona (100%) generally prepared their own crack, usually with ammonia as alkali; in Seville most users (69.7%) bought preprocessed crack. The proportion of users who began taking cocaine (crack or cocaine hydrochloride) by smoking has increased progressively since the seventies, rising to 74.1% in Seville, 61.5% in Madrid, and 28% in Barcelona in 1992-1995, with the earliest increase in Seville. The factors associated with crack use were: residence in Seville (odds ratio (OR) = 16.3), cocaine hydrochloride use mainly by smoking (OR = 5.0), by sniffing (OR = 2.7) or by injecting (OR = 2.5), heroin use mainly by smoking (OR = 2.8) and weekly use of cannabis (OR = 1.9). CONCLUSIONS: In Spain smoking cocaine may be progressively diffusing from the south west to the north east, similar to what has happened with smoking heroin, but beginning later in time. The factors associated with smoking cocaine are basically ecological or cultural in nature (characteristics of the available drugs and the main route of heroin administration in each city).

 

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OBJECT: Image guidance provides a three-dimensional view of the lesion and allows the surgeon to plan a surgical strategy that takes the relationship of the lesion and the surrounding brain into account. We evaluated the degree of resection and the functional outcome of patients with colloid cysts from the third ventricle submitted to surgical resection using interactive image-guided approach. METHOD: Using image-guided methodology and an endoscopic approach we analyzed the functional outcome of 11 patients with diagnosis of colloid cyst of the third ventricle who were treated at our institution from August 1993 to September 2000. The mean age was 39.5 years and the mean follow-up was 36.5 months. Analyzing the clinical outcome, 54.5% of the patients developed short-term memory disturbance in the first 30 days after surgery. None of these patients persisted with this symptomatology for more than one month. In terms of late post-operative morbidity, 1 patient developed persistent post-operative seizures, which were controlled with anti-seizure medications. Complete resection of the cyst was achieved in all patients. CONCLUSIONS: The low rate of complications and high rate of total resection encourage us to continue using the multimodal technique. Longer follow-up and an increase in the number of patients are needed to assess the efficacy of this methodology.  相似文献   
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Small calcium-mobilizing inflammatory mediators have been implicated in joint pathology. Here we demonstrate that bradykinin, adenosine 5′-triphosphate, uridine 5′-triphosphate, and lysophosphatidic acid raise the intracellular calcium concentration ([Ca2+]i) in human articular chondrocytes. Heterologous cross-desensitization experiments showed that the uridine 5′-triphosphate response was abolished by prior treatment with adenosine 5′-triphosphate and conversely, that the adenosine 5′-triphosphate response was abolished by prior treatment with uridine 5′-triphosphate: this indicated competition for the same receptor site, whereas bradykinin and lysophosphatidic acid did not compete with other ligands. Pretreatment with thapsigargin abolished ligand-mediated Ca2+ responses but not vice versa: this confirmed that Ca2+ release occurred from intracellular stores. Single-cell analysis of Fura-2 acetoxymethyl ester loaded chondrocytes showed mediator-dependent patterns of oscillatory Ca2+ changes in a subset of cells when challenged with submaximal concentrations of bradykinin, adenosine 5′-triphosphate, or uridine 5′-triphosphate in the presence of extracellular Ca2+. However, no oscillatory responses were seen after a challenge with lysophosphatidic acid. Therefore, although a number of different Ca2+-mobilizing ligands activate chondrocytes, the differences that occur in the temporal patterning of Ca2+ responses may result in unique mediator-dependent changes in cellular activity.  相似文献   
38.
This study aims at assessing the accuracy of estimates of body composition provided by bioimpedance (BIA) equations developed for U.S. populations when applied to a sample of Guatemalan farmers. If these equations were shown to have low validity, the second objective was to develop more accurate estimates of fat-free mass (FFM). One hundred males and females 19 to 45 years of age were randomly selected from four rural communities in the Western Highlands of Guatemala. Bioimpedance equations explained 59 and 33% of the variation in FFM, with a RMSE of 2.7 and 2.8 kg in males and females, respectively. Body fat (BF) predictions had a lower R2. Using the “all possible regressions” procedure, the best subset for prediction of FFM used anthropometric and BIA variables as predictors. The best model for men and women included only anthropometric variables: 75% of the variance in FFM for men and 70% of the variance in women was explained by this model. The RMSE was 2.1 and 1.9 kg for both groups, respectively. It is concluded that FFM can be estimated from anthropometric dimensions with a high degree of accuracy and use of BIA does not provide more valid estimates.  相似文献   
39.
Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models.  相似文献   
40.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
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