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Shock (Augusta, Ga.) Jan 2017The acute respiratory distress syndrome (ARDS) is a life-threating disorder that contributes significantly to critical illness. No specific pharmacological interventions... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The acute respiratory distress syndrome (ARDS) is a life-threating disorder that contributes significantly to critical illness. No specific pharmacological interventions directed at lung injury itself have proven effective in improving outcome of patients with ARDS. Platelet activation was identified as a key component in ARDS pathophysiology and may provide an opportunity for preventive and therapeutic strategies. We hypothesize that use of acetyl salicylic acid (ASA) may prevent and/or attenuate lung injury.
METHODS
We conducted a systematic review of preclinical studies and meta-analysis of clinical studies investigating the efficacy of ASA in the setting of lung injury. Medline, embase, and cochrane databases were searched.
RESULTS
The literature search yielded 1,314 unique articles. Fifteen preclinical studies and eight clinical studies fulfilled the in- and exclusion criteria. In the animal studies, the overall effect of ASA was positive, e.g., ASA improved survival and attenuated inflammation and pulmonary edema. Mechanisms of actions involved, among others, are interference with the neutrophil-platelets interaction, reduction of leukotrienes, neutrophil extracellular traps, and prostaglandins. High-dose ASA may be the drug of choice. A meta-analysis of three clinical studies showed an association between ASA use and a reduced incidence of ARDS (OR 0.59, 95% CI 0.36-0.98), albeit with substantial between-study heterogeneity. All studies had their own shortcomings in methodological quality.
CONCLUSION
This systematic review of preclinical studies and meta-analysis of clinical studies suggests a beneficial role for ASA in ARDS prevention and treatment. However, the currently available data is insufficient to justify an indication for ASA in ARDS. The body of literature does support further studies in humans. We suggest clinical trials in which the mechanisms of action of ASA in lung injury models are being evaluated to guide optimal timing and dose, before prospective randomized trials.
Topics: Animals; Aspirin; Humans; Platelet Activation; Respiratory Distress Syndrome
PubMed: 27984533
DOI: 10.1097/SHK.0000000000000745 -
Life (Basel, Switzerland) Jul 2021The processing of the amyloid precursor protein (APP) is a critical event in the formation of amyloid plaques. Platelets contain most of the enzymatic machinery required... (Review)
Review
The processing of the amyloid precursor protein (APP) is a critical event in the formation of amyloid plaques. Platelets contain most of the enzymatic machinery required for APP processing and correlates of intracerebral abnormalities have been demonstrated in platelets of patients with AD. The goal of the present paper was to analyze studies exploring platelet APP metabolism in Alzheimer's disease patients trying to assess potential reliable peripheral biomarkers, to offer new therapeutic solutions and to understand the pathophysiology of the AD. According to the PRISMA guidelines, we performed a systematic review through the PubMed database up to June 2020 with the search terms: "((((((APP) OR Amyloid Precursor Protein) OR AbetaPP) OR Beta Amyloid) OR Amyloid Beta) OR APP-processing) AND platelet". Thirty-two studies were included in this systematic review. The papers included are analytic observational studies, namely twenty-nine cross sectional studies and three longitudinal studies, specifically prospective cohort study. The studies converge in an almost unitary way in affirming that subjects with AD show changes in APP processing compared to healthy age-matched controls. However, the problem of the specificity and sensitivity of these biomarkers is still at issue and would deserve to be deepened in future studies.
PubMed: 34440494
DOI: 10.3390/life11080750 -
Journal of Thrombosis and Haemostasis :... Jun 2015Left ventricular assist devices (LVADs) have dramatically increased the survival of adults with end-stage systolic heart failure. However, rates of bleeding and... (Review)
Review
BACKGROUND
Left ventricular assist devices (LVADs) have dramatically increased the survival of adults with end-stage systolic heart failure. However, rates of bleeding and thromboembolism remain high.
OBJECTIVES
We completed a systematic review to evaluate outcomes of adults with LVADs treated with various anticoagulant and antiplatelet strategies.
METHODS
Databases were searched using the terms 'assist device', 'thrombosis', and 'anticoagulant' or 'platelet aggregation inhibitor' with appropriate synonyms, device names and manufacturers.
RESULTS AND CONCLUSIONS
Of 977 manuscripts, 24 articles met the inclusion criteria of adults with implanted LVADs where clinical outcomes were defined based on anticoagulant and/or antiplatelet regimen. Most studies reported treatment with unfractionated heparin post-operatively which was transitioned to a vitamin K antagonist (VKA). Goal INR varied between 1.5-3.5. Antiplatelet regimens ranged from no treatment to dual therapy. Definition of major bleeding differed between trials and incidence varied between 0% and 58%. The available evidence could not demonstrate a clear benefit of aspirin compared with VKA therapy alone [stroke RR 1.02 (95% CI 0.49-2.1)]. There was a suggestion that treatment with aspirin and dipyridamole decreased the risk of thromboembolism compared to aspirin [RR 0.50 (0.36-0.68)], but the comparison is limited by differences in demographics, devices, and INR goals among studies. Additionally, most studies did not blind investigators to outcomes thus contributing to an increased risk for bias. Clinical equipoise exists as to the most appropriate antithrombotic therapy in LVAD patients. Randomization between regimens within a prospective trial is needed to define the treatment regimen that minimizes both bleeding and thrombotic complications.
Topics: Anticoagulants; Blood Coagulation; Chi-Square Distribution; Drug Monitoring; Fibrinolytic Agents; Heart Failure; Heart-Assist Devices; Hemorrhage; Humans; International Normalized Ratio; Odds Ratio; Platelet Aggregation; Platelet Aggregation Inhibitors; Predictive Value of Tests; Prosthesis Design; Risk Assessment; Risk Factors; Thrombosis; Treatment Outcome; Ventricular Function, Left
PubMed: 25845489
DOI: 10.1111/jth.12948 -
PloS One 2024This study aimed to evaluate the intervention effect of curcumin on hepatic fibrosis in rodent models through systematic review and meta-analysis, in order to provide... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This study aimed to evaluate the intervention effect of curcumin on hepatic fibrosis in rodent models through systematic review and meta-analysis, in order to provide meaningful guidance for clinical practice.
METHODS
A systematic retrieval of relevant studies on curcumin intervention in rats or mice hepatic fibrosis models was conducted, and the data were extracted. The outcome indicators included liver cell structure and function related indicators, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), albumin (ALB), ratio of albumin to globulin (A/G), total bilirubin (TBIL), bax protein, bcl-2 protein and index of liver, as well as the relevant indicators for evaluating the degree of hepatic fibrosis, such as hyaluronic acid (HA), laminin (LN), type I collagen (Collagen I), type III collagen (Collagen III), type III procollagen (PCIII), type III procollagen amino terminal peptide (PIIINP), type IV collagen (IV-C), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), α-Smooth muscle actin (α-SMA), hydroxyproline (HYP), platelet derived factor-BB (PDGF-BB), connective tissue growth factor (CTGF) and transforming growth factor-β1 (TGF-β1), and oxidative stress-related indicators, such as superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px). These results were then analyzed by meta-analysis. Studies were evaluated for methodological quality using the syrcle's bias risk tool.
RESULTS
A total of 59 studies were included in the meta-analysis, and the results showed that curcumin can reduce the levels of ALT, AST, ALP, TBIL, bax protein, and index of liver in hepatic fibrosis models. It can also reduce HA, LN, Collagen I, Collagen III, PCIII, PIIINP, IV-C, TNF-α, α-SMA, HYP, PDGF-BB, CTGF, TGF-β1 and MDA, and increase the levels of ALB, A/G, SOD, and GSH-Px in the hepatic fibrosis models. However, the effects of curcumin on bcl-2 protein, IL-6 in hepatic fibrosis models and index of liver in mice were not statistically significant.
CONCLUSION
The analysis results indicate that curcumin can reduce liver cell apoptosis by maintaining the stability of liver cell membrane, inhibit the activation and proliferation of hepatic stellate cells by reducing inflammatory response, and alleviate tissue peroxidation damage by clearing oxygen free radicals.
Topics: Animals; Liver Cirrhosis; Curcumin; Mice; Rats; Disease Models, Animal; Oxidative Stress; Liver
PubMed: 38781262
DOI: 10.1371/journal.pone.0304176 -
Thrombosis and Haemostasis Jun 2020The novel coronavirus 2019 (COVID-19) is clinically characterized by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for a high number...
The novel coronavirus 2019 (COVID-19) is clinically characterized by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for a high number of patients needing mechanical ventilation or intensive care units treatment and for the elevated mortality risk. A link between COVID-19 and multiorgan failure may be dependent on the fact that most COVID-19 patients are complicated by pneumonia, which is known to be associated with early changes of clotting and platelet activation and artery dysfunction; these changes may implicate in thrombotic-related events such as myocardial infarction and ischemic stroke. Recent data showed that myocardial injury compatible with coronary ischemia may be detectable in SARS-CoV-2 patients and laboratory data exploring clotting system suggest the presence of a hypercoagulation state. Thus, we performed a systematic review of COVID-19 literature reporting measures of clotting activation to assess if changes are detectable in this setting and their relationship with clinical severity. Furthermore, we discussed the biologic plausibility of the thrombotic risk in SARS-CoV-2 and the potential use of an antithrombotic treatment.
Topics: Algorithms; Betacoronavirus; COVID-19; Cardiology; Coronavirus Infections; Fibrin Fibrinogen Degradation Products; Fibrinolytic Agents; Humans; Liver Failure; Pandemics; Partial Thromboplastin Time; Platelet Count; Pneumonia, Viral; Prothrombin Time; Risk; SARS-CoV-2; Thrombophilia; Thrombosis; Treatment Outcome
PubMed: 32349133
DOI: 10.1055/s-0040-1710317 -
Medical Devices (Auckland, N.Z.) 2021Adequate hemostasis during surgical procedures is essential for successful patient outcomes and reduced healthcare resource utilization. Topical hemostatic agents can... (Review)
Review
Adequate hemostasis during surgical procedures is essential for successful patient outcomes and reduced healthcare resource utilization. Topical hemostatic agents can act as catalysts for the clotting cascade or as a scaffold to promote platelet activation or aggregation. Although an ever-increasing number of topical absorbable hemostatic agents are now available for perioperative use, health care providers are disadvantaged by the lack of comparative data on feasibility, clinical effectiveness, advantages, and limitations of each in specific surgical settings. This knowledge is important for appropriate product choice when patient characteristics, type of surgical procedure, type of bleeding, and product availability may differ widely. This manuscript provides the first comprehensive overview of Avitene™ Microfibrillar Collagen Hemostat (MCH), a bovine collagen-based absorbable hemostat that has been widely used for over four decades in the United States and abroad. MCH is indicated as an adjunct to hemostasis across a broad spectrum of surgical specialties and has been shown to achieve hemostasis with positive patient outcomes and a favorable safety profile in many applications, including hepatic, orthopedic, splenic, oral, and otolaryngologic surgery. Although published clinical data regarding the use of MCH in cardiovascular surgery is limited, evidence suggests moderate use in this specialty. The information contained in this systematic review will help health care providers understand the clinical use and effectiveness of the product to determine appropriate use in differing bleeding scenarios across multiple surgical specialties. Future studies may include comparative functional and cost analyses to explore the economic advantages of using absorbable hemostatic agents compared with each other or with conventional techniques of hemostasis, when appropriate.
PubMed: 34104007
DOI: 10.2147/MDER.S298207 -
Medicine Feb 2021Exercise test (ET) may have adverse effects on platelet function and induce acute thrombotic events in patients with coronary artery disease (CAD). The aim of this study... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Exercise test (ET) may have adverse effects on platelet function and induce acute thrombotic events in patients with coronary artery disease (CAD). The aim of this study is to investigate the platelet function and evaluate the risk of thrombotic events in CAD patients during ET.
METHODS
Pubmed, Embase, Cochrane Library, and Web of Science were searched for a systematic review from initiation to October 2019. The inclusion criteria were controlled clinical trails as study design; investigating platelet function in CAD patients during ET; with ET carried out by treadmill or bicycle ergometer; written in English. Included articles were screened based on title/abstract and full-text review by 2 independent reviewers. Platelet aggregation (PA), platelet surface expression of CD62p and PAC-1, plasma levels of platelet factor 4 (PF4) and beta-thromboglobulin (β-TG) were evaluated before and after ET.
RESULTS
Eighteen articles were included out of the 427 references initially identified. In most of the studies included ET was terminated because of limited symptoms. Prior to ET, no difference in platelet aggregation was observed in CAD patients compared with healthy controls in majority of the studies, with or without the treatment with Aspirin. Dual anti-platelet therapy suppressed adenosine diphosphate (ADP)-induced platelet aggregation at rest. After ET, platelet aggregation, the serum levels of β-thromboglobulin were found unchanged in majority of studies and platelet factor-4 were found unchanged in half of studies. The expression of platelet surface markers were elevated by ET in a few study.
CONCLUSION
Symptom-limited exercise test did not affect platelet function in patients with coronary artery disease; however exercise to higher intensity may induce platelet activation.
Topics: Cardiac Rehabilitation; Coronary Artery Disease; Exercise Test; Humans; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Function Tests
PubMed: 33663130
DOI: 10.1097/MD.0000000000024932 -
The Cochrane Database of Systematic... Dec 2021Depression occurs frequently in individuals with coronary artery disease (CAD) and is associated with a poor prognosis. (Review)
Review
BACKGROUND
Depression occurs frequently in individuals with coronary artery disease (CAD) and is associated with a poor prognosis.
OBJECTIVES
To determine the effects of psychological and pharmacological interventions for depression in CAD patients with comorbid depression.
SEARCH METHODS
We searched the CENTRAL, MEDLINE, Embase, PsycINFO, and CINAHL databases up to August 2020. We also searched three clinical trials registers in September 2021. We examined reference lists of included randomised controlled trials (RCTs) and contacted primary authors. We applied no language restrictions.
SELECTION CRITERIA
We included RCTs investigating psychological and pharmacological interventions for depression in adults with CAD and comorbid depression. Our primary outcomes included depression, mortality, and cardiac events. Secondary outcomes were healthcare costs and utilisation, health-related quality of life, cardiovascular vital signs, biomarkers of platelet activation, electrocardiogram wave parameters, non-cardiac adverse events, and pharmacological side effects.
DATA COLLECTION AND ANALYSIS
Two review authors independently examined the identified papers for inclusion and extracted data from the included studies. We performed random-effects model meta-analyses to compute overall estimates of treatment outcomes.
MAIN RESULTS
Thirty-seven trials fulfilled our inclusion criteria. Psychological interventions may result in a reduction in end-of-treatment depression symptoms compared to controls (standardised mean difference (SMD) -0.55, 95% confidence interval (CI) -0.92 to -0.19, I = 88%; low certainty evidence; 10 trials; n = 1226). No effect was evident on medium-term depression symptoms one to six months after the end of treatment (SMD -0.20, 95% CI -0.42 to 0.01, I = 69%; 7 trials; n = 2654). The evidence for long-term depression symptoms and depression response was sparse for this comparison. There is low certainty evidence that psychological interventions may result in little to no difference in end-of-treatment depression remission (odds ratio (OR) 2.02, 95% CI 0.78 to 5.19, I = 87%; low certainty evidence; 3 trials; n = 862). Based on one to two trials per outcome, no beneficial effects on mortality and cardiac events of psychological interventions versus control were consistently found. The evidence was very uncertain for end-of-treatment effects on all-cause mortality, and data were not reported for end-of-treatment cardiovascular mortality and occurrence of myocardial infarction for this comparison. In the trials examining a head-to-head comparison of varying psychological interventions or clinical management, the evidence regarding the effect on end-of-treatment depression symptoms is very uncertain for: cognitive behavioural therapy compared to supportive stress management; behaviour therapy compared to person-centred therapy; cognitive behavioural therapy and well-being therapy compared to clinical management. There is low certainty evidence from one trial that cognitive behavioural therapy may result in little to no difference in end-of-treatment depression remission compared to supportive stress management (OR 1.81, 95% CI 0.73 to 4.50; low certainty evidence; n = 83). Based on one to two trials per outcome, no beneficial effects on depression remission, depression response, mortality rates, and cardiac events were consistently found in head-to-head comparisons between psychological interventions or clinical management. The review suggests that pharmacological intervention may have a large effect on end-of-treatment depression symptoms (SMD -0.83, 95% CI -1.33 to -0.32, I = 90%; low certainty evidence; 8 trials; n = 750). Pharmacological interventions probably result in a moderate to large increase in depression remission (OR 2.06, 95% CI 1.47 to 2.89, I = 0%; moderate certainty evidence; 4 trials; n = 646). We found an effect favouring pharmacological intervention versus placebo on depression response at the end of treatment, though strength of evidence was not rated (OR 2.73, 95% CI 1.65 to 4.54, I = 62%; 5 trials; n = 891). Based on one to four trials per outcome, no beneficial effects regarding mortality and cardiac events were consistently found for pharmacological versus placebo trials, and the evidence was very uncertain for end-of-treatment effects on all-cause mortality and myocardial infarction. In the trials examining a head-to-head comparison of varying pharmacological agents, the evidence was very uncertain for end-of-treatment effects on depression symptoms. The evidence regarding the effects of different pharmacological agents on depression symptoms at end of treatment is very uncertain for: simvastatin versus atorvastatin; paroxetine versus fluoxetine; and escitalopram versus Bu Xin Qi. No trials were eligible for the comparison of a psychological intervention with a pharmacological intervention.
AUTHORS' CONCLUSIONS
In individuals with CAD and depression, there is low certainty evidence that psychological intervention may result in a reduction in depression symptoms at the end of treatment. There was also low certainty evidence that pharmacological interventions may result in a large reduction of depression symptoms at the end of treatment. Moderate certainty evidence suggests that pharmacological intervention probably results in a moderate to large increase in depression remission at the end of treatment. Evidence on maintenance effects and the durability of these short-term findings is still missing. The evidence for our primary and secondary outcomes, apart from depression symptoms at end of treatment, is still sparse due to the low number of trials per outcome and the heterogeneity of examined populations and interventions. As psychological and pharmacological interventions can seemingly have a large to only a small or no effect on depression, there is a need for research focusing on extracting those approaches able to substantially improve depression in individuals with CAD and depression.
Topics: Adult; Coronary Artery Disease; Depression; Escitalopram; Humans; Psychotherapy; Quality of Life
PubMed: 34910821
DOI: 10.1002/14651858.CD008012.pub4 -
Circulation. Cardiovascular Quality and... Jan 2015Discordant results have been reported on the effects of concomitant use of proton pump inhibitors (PPIs) and dual antiplatelet therapy (DAPT) for cardiovascular... (Meta-Analysis)
Meta-Analysis Review
Conflicting results between randomized trials and observational studies on the impact of proton pump inhibitors on cardiovascular events when coadministered with dual antiplatelet therapy: systematic review.
BACKGROUND
Discordant results have been reported on the effects of concomitant use of proton pump inhibitors (PPIs) and dual antiplatelet therapy (DAPT) for cardiovascular outcomes. We conducted a systematic review comparing the effectiveness and safety of concomitant use of PPIs and DAPT in the postdischarge treatment of unstable angina/non-ST-segment-elevation myocardial infarction patients.
METHODS AND RESULTS
We searched for clinical studies in MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews, from 1995 to 2012. Reviewers screened and extracted data, assessed applicability and quality, and graded the strength of evidence. We performed meta-analyses of direct comparisons when outcomes and follow-up periods were comparable. Thirty-five studies were eligible. Five (4 randomized controlled trials and 1 observational) assessed the effect of omeprazole when added to DAPT; the other 30 (observational) assessed the effect of PPIs as a class when compared with no PPIs. Random-effects meta-analyses of the studies assessing PPIs as a class consistently reported higher event rates in patients receiving PPIs for various clinical outcomes at 1 year (composite ischemic end points, all-cause mortality, nonfatal MI, stroke, revascularization, and stent thrombosis). However, the results from randomized controlled trials evaluating omeprazole compared with placebo showed no difference in ischemic outcomes, despite a reduction in upper gastrointestinal bleeding with omeprazole.
CONCLUSIONS
Large, well-conducted observational studies of PPIs and randomized controlled trials of omeprazole seem to provide conflicting results for the effect of PPIs on cardiovascular outcomes when coadministered with DAPT. Prospective trials that directly compare pharmacodynamic parameters and clinical events among specific PPI agents in patients with unstable angina/non-ST-segment-elevation myocardial infarction treated with DAPT are warranted.
Topics: Angina, Unstable; Cardiovascular Diseases; Drug Interactions; Drug Therapy, Combination; Evidence-Based Medicine; Gastrointestinal Hemorrhage; Humans; Myocardial Infarction; Observational Studies as Topic; Odds Ratio; Platelet Aggregation; Platelet Aggregation Inhibitors; Proton Pump Inhibitors; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Treatment Outcome
PubMed: 25587094
DOI: 10.1161/CIRCOUTCOMES.114.001177 -
The Cochrane Database of Systematic... Oct 2009Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events, reducing the odds of such events among high vascular risk... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events, reducing the odds of such events among high vascular risk patients by about a quarter. Thienopyridine derivatives inhibit platelet activation by a different mechanism and so may be more effective.
OBJECTIVES
To determine the effectiveness and safety of thienopyridine derivatives (ticlopidine and clopidogrel) versus aspirin for preventing serious vascular events (stroke, myocardial infarction (MI) or vascular death) in patients at high risk, and specifically in patients with a previous TIA or ischaemic stroke.
SEARCH STRATEGY
We searched the trials registers of the Stroke, Heart and Peripheral Vascular Diseases Cochrane Review Groups (last searched July 2008), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2008), MEDLINE (1966 to August 2008) and EMBASE (1980 to August 2008). We also searched reference lists of relevant papers, and contacted other researchers and the pharmaceutical company Sanofi-BMS (December 2008).
SELECTION CRITERIA
All unconfounded, double blind, randomised trials directly comparing a thienopyridine derivative with aspirin in high vascular risk patients.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data and assessed trial quality. We sought additional data from the principal investigators of the largest trials.
MAIN RESULTS
We included 10 trials involving 26,865 high vascular risk patients. The trials were generally of high quality. Aspirin was compared with ticlopidine in nine trials (7633 patients) and with clopidogrel in one trial (19,185 patients). Compared with aspirin, allocation to a thienopyridine produced a modest, just statistically significant, reduction in the odds of a serious vascular event (11.6% versus 12.5%; odds ratio (OR) 0.92, 95% confidence interval (CI) 0.85 to 0.99), corresponding to the avoidance of 10 (95% CI 0 to 20) serious vascular events per 1000 patients treated for about two years. However, the wide confidence interval includes the possibility of negligible additional benefit. Compared with aspirin, thienopyridines significantly reduced gastrointestinal adverse effects. However, thienopyridines increased the odds of skin rash and diarrhoea, ticlopidine more than clopidogrel. Allocation to ticlopidine, but not clopidogrel, significantly increased the odds of neutropenia. In patients with TIA/ischaemic stroke, the results were similar to those for all patients combined.
AUTHORS' CONCLUSIONS
The thienopyridine derivatives are at least as effective as aspirin in preventing serious vascular events in patients at high risk, and possibly somewhat more so. However, the size of any additional benefit is uncertain and could be negligible. Clopidogrel has a more favourable adverse effects profile than ticlopidine and so is the thienopyridine of choice. It should be used as an alternative to aspirin in patients genuinely intolerant of or allergic to aspirin.
Topics: Aspirin; Cardiovascular Diseases; Clopidogrel; Humans; Myocardial Infarction; Platelet Aggregation Inhibitors; Randomized Controlled Trials as Topic; Stroke; Ticlopidine
PubMed: 19821273
DOI: 10.1002/14651858.CD001246.pub2