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81.
PURPOSE: To assess if lipid-lowering interventions (statins, fibrates, resins, n-3 fatty acids, diet) prevent nonfatal and fatal strokes in patients with and without coronary heart disease. METHODS: We systematically searched the literature up to August 2002 to retrieve all randomized controlled trials of lipid-lowering interventions that reported nonfatal and fatal stroke and mortality data. The search yielded 65 trials with 200,607 patients for a meta-analysis to determine whether treatment effects differed between types of lipid-lowering interventions and between patient samples with and without coronary heart disease. RESULTS: The risk ratio for nonfatal and fatal stroke for statins as compared with control interventions was 0.82 (95% confidence interval [CI]: 0.76 to 0.90). The corresponding risk ratios for statins as compared with control were 0.75 (95% CI: 0.65 to 0.87) for patients with coronary heart disease and 0.77 (95% CI: 0.62 to 0.95) for those without coronary heart disease. The confidence intervals of risk ratios for nonfatal and fatal stroke associated with fibrates, resins, n-3 fatty acids, and diet all included 1, as did the confidence intervals for these interventions in patients with and without coronary heart disease. Weighted meta-regression analysis suggested a stronger association of stroke reduction with statin treatment than with the extent of cholesterol reduction. CONCLUSION: This meta-analysis suggests that statins reduce the incidence of stroke in patients with and without coronary heart disease.  相似文献   
82.
Assessment of aldehyde dehydrogenase in viable cells   总被引:3,自引:4,他引:3  
Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.  相似文献   
83.
84.
In recent years, multiple loci dispersed on the genome have been shown to be associated with coronary artery disease (CAD). We investigated whether these common genetic variants also hold value for CAD prediction in a large cohort of patients with familial hypercholesterolemia (FH). We genotyped a total of 41 single-nucleotide polymorphisms (SNPs) in 1701 FH patients, of whom 482 patients (28.3%) had at least one coronary event during an average follow up of 66 years. The association of each SNP with event-free survival time was calculated with a Cox proportional hazard model. In the cardiovascular disease risk factor adjusted analysis, the most significant SNP was rs1122608:G>T in the SMARCA4 gene near the LDL-receptor (LDLR) gene, with a hazard ratio for CAD risk of 0.74 (95% CI 0.49–0.99; P-value 0.021). However, none of the SNPs reached the Bonferroni threshold. Of all the known CAD loci analyzed, the SMARCA4 locus near the LDLR had the strongest negative association with CAD in this high-risk FH cohort. The effect is contrary to what was expected. None of the other loci showed association with CAD.  相似文献   
85.
Non-alcoholic fatty liver disease(NAFLD)ranges from simple steatosis to nonalcoholic steatohepatitis(NASH),leading to fibrosis and potentially cirrhosis,and it is one of the most common causes of liver disease worldwide.NAFLD is associated with other medical conditions such as metabolic syndrome,obesity,cardiovascular disease and diabetes.NASH can only be diagnosed through liver biopsy,but noninvasive techniques have been developed to identify patients who are most likely to have NASH or fibrosis,reducing the need for liver biopsy and risk to patients.Disease progression varies between individuals and is linked to a number of risk factors.Mechanisms involved in the pathogenesis are associated with diet and lifestyle,influx of free fatty acids to the liver from adipose tissue due to insulin resistance,hepatic oxidative stress,cytokines production,reduced very low-density lipoprotein secretion and intestinal microbiome.Weight loss through improved diet and increased physical activity has been the cornerstone therapy of NAFLD.Recent therapies such as pioglitazone and vitamin E have been shown to be beneficial.Omega 3 polyunsaturated fatty acids and statins may offer additional benefits.Bariatric surgery should be considered in morbidly obese patients.More research is needed to assess the impact of these treatments on a long-term basis.The objective of this article is to briefly review the diagnosis,management and treatment of this disease in order to aid clinicians in managing these patients.  相似文献   
86.
Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes.  相似文献   
87.
The mathematical theory of compressed sensing (CS) asserts that one can acquire signals from measurements whose rate is much lower than the total bandwidth. Whereas the CS theory is now well developed, challenges concerning hardware implementations of CS-based acquisition devices--especially in optics--have only started being addressed. This paper presents an implementation of compressive sensing in fluorescence microscopy and its applications to biomedical imaging. Our CS microscope combines a dynamic structured wide-field illumination and a fast and sensitive single-point fluorescence detection to enable reconstructions of images of fluorescent beads, cells, and tissues with undersampling ratios (between the number of pixels and number of measurements) up to 32. We further demonstrate a hyperspectral mode and record images with 128 spectral channels and undersampling ratios up to 64, illustrating the potential benefits of CS acquisition for higher-dimensional signals, which typically exhibits extreme redundancy. Altogether, our results emphasize the interest of CS schemes for acquisition at a significantly reduced rate and point to some remaining challenges for CS fluorescence microscopy.  相似文献   
88.

Purpose

Anxiolytic and possible side effects of clonidine 150?μg compared to midazolam 7.5?mg for premedication in surgical wisdom tooth extraction were evaluated.

Methods

In a prospective, randomized, double-blind crossover trial, ten patients undergoing bilateral wisdom tooth surgery received clonidine or midazolam orally 1?h before the treatment. Patients receiving midazolam for the first surgery received clonidine at the second surgery and vice versa. The anxiolytic efficacy was evaluated with a visual analogue scale (VAS) upon admission and 30, 50 and 60?min after administration of the medication. Patient satisfaction was recorded on a VAS after surgery and 7?days postoperatively.

Results

As soon as 30?min after administration of midazolam (p?<?0.03) and clonidine (p?<?0.02), an anxiolytic effect was recorded. Both medications did not differ in patient satisfaction.

Conclusion

Oral administration of clonidine 150?μg and midazolam 7.5?mg were rated as medications with equal anxiolytic effects before wisdom tooth surgery under local anesthesia.  相似文献   
89.
90.

Background

Open radical cystectomy (ORC) is associated with substantial blood loss and a high incidence of perioperative blood transfusions. Strategies to reduce blood loss and blood transfusion are warranted.

Objective

To determine whether continuous norepinephrine administration combined with intraoperative restrictive hydration with Ringer's maleate solution can reduce blood loss and the need for blood transfusion.

Design, setting, and participants

This was a double-blind, randomised, parallel-group, single-centre trial including 166 consecutive patients undergoing ORC with urinary diversion (UD). Exclusion criteria were severe hepatic or renal dysfunction, congestive heart failure, and contraindications to epidural analgesia.

Intervention

Patients were randomly allocated to continuous norepinephrine administration starting with 2 μg/kg per hour combined with 1 ml/kg per hour until the bladder was removed, then to 3 ml/kg per hour of Ringer's maleate solution (norepinephrine/low-volume group) or 6 ml/kg per hour of Ringer's maleate solution throughout surgery (control group).

Outcome measurements and statistical analysis

Intraoperative blood loss and the percentage of patients requiring blood transfusions perioperatively were assessed. Data were analysed using nonparametric statistical models.

Results and limitations

Total median blood loss was 800 ml (range: 300–1700) in the norepinephrine/low-volume group versus 1200 ml (range: 400–2800) in the control group (p < 0.0001). In the norepinephrine/low-volume group, 27 of 83 patients (33%) required an average of 1.8 U (±0.8) of packed red blood cells (PRBCs). In the control group, 50 of 83 patients (60%) required an average of 2.9 U (±2.1) of PRBCs during hospitalisation (relative risk: 0.54; 95% confidence interval [CI], 0.38–0.77; p = 0.0006). The absolute reduction in transfusion rate throughout hospitalisation was 28% (95% CI, 12–45). In this study, surgery was performed by three high-volume surgeons using a standardised technique, so whether these significant results are reproducible in other centres needs to be shown.

Conclusions

Continuous norepinephrine administration combined with restrictive hydration significantly reduces intraoperative blood loss, the rate of blood transfusions, and the number of PRBC units required per patient undergoing ORC with UD.  相似文献   
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