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排序方式: 共有801条查询结果,搜索用时 15 毫秒
1.
Venous thromboembolism associated with long-term use of central venous catheters in cancer patients. 总被引:15,自引:0,他引:15
Long-term central venous catheters (CVCs) have considerably improved the management of cancer patients because they facilitate chemotherapy, transfusions, parenteral nutrition, and blood sampling. However, the use of long-term CVCs, especially for chemotherapy, has been associated with the occurrence of upper-limb deep venous thrombosis (UL-DVT). The incidence of clinically overt UL-DVT related to CVCs has been reported to vary between 0.3% and 28.3%. The incidence of CVC-related UL-DVT screened by venography reportedly varies between 27% and 66%. The incidence of clinically overt pulmonary embolism (PE) in patients with CVC-related UL-DVT ranges from 15% to 25%, but an autopsy-proven PE rate of up to 50% has been reported. Vessel injury caused by the procedure of CVC insertion, venous stasis caused by the indwelling CVC, and cancer-related hypercoagulability are the main pathogenetic factors for CVC-related venous thromboembolism (VTE). Several studies have assessed the benefit of the prophylaxis of UL-DVT after CVC insertion in cancer patients. According to the results of these studies, prophylaxis with low molecular weight heparin or a low fixed dose of warfarin has been recently proposed. However, the limitations of the experimental design of the prophylactic studies do not allow definitive recommendations. The recommended therapy for UL-DVT associated with CVC is based on anticoagulant therapy with or without catheter removal. This review focuses on the epidemiology, pathogenesis, diagnosis, prevention, and treatment of VTE in cancer patients with long-term CVC. 相似文献
2.
Melina Verso Giancarlo Agnelli Sergio Bertoglio Franco C Di Somma Francesco Paoletti Walter Ageno Mario Bazzan Pasquale Parise Roberto Quintavalla Emanuele Naglieri Armando Santoro Davide Imberti Mariella Sorarù Stefano Mosca 《Journal of clinical oncology》2005,23(18):4057-4062
PURPOSE: The extent of venous thromboembolism (VTE) associated with central vein catheters (CVC) in cancer patients remains unclear. The aim of this study was to evaluate the efficacy and safety of the low molecular weight heparin, enoxaparin, in the prevention of VTE. PATIENTS AND METHODS: In a multicenter, double-blind study, consecutive cancer patients scheduled for CVC insertion were randomly assigned to receive either subcutaneous enoxaparin 40 mg once a day or placebo. Treatment was started 2 hours before CVC insertion and continued for 6 weeks. The primary end points of the study were deep vein thrombosis (DVT), confirmed by venography of the CVC limb performed 6 weeks after randomization, or clinically overt pulmonary embolism, confirmed by objective testing during the study drug administration. Patients were assessed for bleeding complications. RESULTS: Three hundred eighty-five patients were randomized, of which 321 (83.4%) underwent venography. A venography was adequate for adjudication in 155 patients in each treatment group. A DVT was observed in 22 patients (14.1%) treated with enoxaparin and in 28 patients (18.0%) treated with placebo, corresponding to a relative risk of 0.78 (95% CI, 0.47 to 1.31). No major bleeding occurred. Five patients (2.6%) in the enoxaparin group and two patients (1.0%) in the placebo group died during the treatment period. CONCLUSION: In this study, no difference in the rate of CVC-related VTE was detected between patients receiving enoxaparin and patients receiving placebo. The dose of enoxaparin used in this study proved to be safe. Clinical trials evaluating higher enoxaparin doses could optimize the efficacy of this agent for this indication. 相似文献
3.
Kristine Korzow Richter Maria C. Codlin Melina Seabrook Christina Warinner 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(20)
Collagen peptide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, also known as zooarchaeology by mass spectrometry (ZooMS), is a rapidly growing analytical technique in the fields of archaeology, ecology, and cultural heritage. Minimally destructive and cost effective, ZooMS enables rapid taxonomic identification of large bone assemblages, cultural heritage objects, and other organic materials of animal origin. As its importance grows as both a research and a conservation tool, it is critical to ensure that its expanding body of users understands its fundamental principles, strengths, and limitations. Here, we outline the basic functionality of ZooMS and provide guidance on interpreting collagen spectra from archaeological bones. We further examine the growing potential of applying ZooMS to nonmammalian assemblages, discuss available options for minimally and nondestructive analyses, and explore the potential for peptide mass fingerprinting to be expanded to noncollagenous proteins. We describe the current limitations of the method regarding accessibility, and we propose solutions for the future. Finally, we review the explosive growth of ZooMS over the past decade and highlight the remarkably diverse applications for which the technique is suited. 相似文献
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Michael L Sion Melina C Armenaka Ioannis Georgiadis Georgios Paraskevopoulos Ioannis Nikolaidis 《Thyroid》2004,14(9):786-788
Thyroid invasion by Aspergillus spp. can occur with invasive aspergillosis, although it is rarely diagnosed antemortem. We describe a case of multiple thyroid abscesses from A. fumigatus that caused esophageal obstruction in a patient with myelodysplasia. Despite aggressive antifungal treatment, the outcome was rapidly fatal. 相似文献
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Rochelle Melina Kinson Song Guo Yi Min Wan Victoria Manning Hui Chin Teoh Kim Eng Wong 《Singapore medical journal》2015,56(2):87-91
INTRODUCTION
There is a paucity of local data on the prevalence of blood transmitted infections (BTIs), such as hepatitis B, hepatitis C and human immunodeficiency virus (HIV) infections, among illicit drug users. This study aimed to examine the prevalence of BTIs among substance-dependent inpatients and identify the factors associated with BTIs.METHODS
We conducted a retrospective case note analysis of 170 inpatients who had a history of substance dependence and were seen at the National Addictions Management Service, Singapore, between 1 June 2009 and 31 May 2010.RESULTS
The majority of the 170 inpatients were male (88.2%) and Chinese (58.2%). The mean age of the patients was 43.1 years, and the main drug of abuse was opioids (86.5%). BTIs were found in 70 (41.2%) inpatients; the prevalence of hepatitis B, hepatitis C and HIV infections was 3.7%, 39.6% and 0%, respectively. Lifetime intravenous drug use, but not needle-sharing, was more common among inpatients who were positive for BTIs (p < 0.01). Logistic regression analysis showed that lifetime intravenous drug use (OR 4.3, 95% CI 1.7–10.8, p < 0.01) was the only significant predictor of BTI.CONCLUSION
41.2% of the substance users seeking help were positive for at least one BTI. Lifetime intravenous drug users were found to be more than four times more likely to have a BTI. Early detection and prevention is essential to improve prognosis. 相似文献10.
uPA‐uPAR molecular complex is involved in cell signaling during neuronal migration and neuritogenesis 下载免费PDF全文
Noelia Lino Luciano Fiore Melina Rapacioli Luisa Teruel Vladimir Flores Gabriel Scicolone Viviana Sánchez 《Developmental dynamics》2014,243(5):676-689
Background: In the development of the central nervous system (CNS), neuronal migration and neuritogenesis are crucial processes for establishing functional neural circuits. This relies on the regulation exerted by several signaling molecules, which play important roles in axonal growth and guidance. The urokinase‐type plasminogen activator (uPA)—in association with its receptor—triggers extracellular matrix proteolysis and other cellular processes through the activation of intracellular signaling pathways. Even though the uPA‐uPAR complex is well characterized in nonneuronal systems, little is known about its signaling role during CNS development. Results : In response to uPA, neuronal migration and neuritogenesis are promoted in a dose‐dependent manner. After stimulation, uPAR interacts with α5‐ and β1‐integrin subunits, which may constitute an αβ‐heterodimer that acts as a uPA‐uPAR coreceptor favoring the activation of multiple kinases. This interaction may be responsible for the uPA‐promoted phosphorylation of focal adhesion kinase (FAK) and its relocation toward growth cones, triggering cytoskeletal reorganization which, in turn, induces morphological changes related to neuronal migration and neuritogenesis. Conclusions : uPA has a key role during CNS development. In association with its receptor, it orchestrates both proteolytic and nonproteolytic events that govern the proper formation of neural networks. Developmental Dynamics 243:676–689, 2014. © 2014 Wiley Periodicals, Inc. 相似文献