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991.
HIV risk behaviors, susceptibility to HIV acquisition, progression of disease after infection, and response to antiretroviral therapy all vary by age. In those living with HIV, current effective treatment has increased the median life expectancy to >70 years of age. Biologic, medical, individual, social, and societal issues change as one ages with HIV infection, but there has been only a small amount of research in this field. Therefore, the Office of AIDS Research of the National Institutes of Health commissioned a working group to develop an outline of the current state of knowledge and areas of critical need for research in HIV and Aging; the working groups' findings and recommendations are summarized in this report. Key overarching themes identified by the group included the following: multimorbidity, polypharmacy, and the need to emphasize maintenance of function; the complexity of assessing HIV versus treatment effects versus aging versus concurrent disease; the inter-related mechanisms of immune senescence, inflammation, and hypercoagulability; the utility of multivariable indices for predicting outcomes; a need to emphasize human studies to account for complexity; and a required focus on issues of community support, caregivers, and systems infrastructure. Critical resources are needed to enact this research agenda and include expanded review panel expertise in aging, functional measures, and multimorbidity, and facilitated use and continued funding to allow long-term follow-up of cohorts aging with HIV.  相似文献   
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993.

Introduction

Renal dysfunction is a common complication in patients with end-stage cirrhosis. Since the original publication of the definition and diagnostic criteria for the hepatorenal syndrome (HRS), there have been major advances in our understanding of its pathogenesis. The prognosis of patients with cirrhosis who develop HRS remains poor, with a median survival without liver transplantation of less than six months. However, a number of pharmacological and other therapeutic strategies have now become available which offer the ability to prevent or treat renal dysfunction more effectively in this setting. Accordingly, we sought to review the available evidence, make recommendations and delineate key questions for future studies.

Methods

We undertook a systematic review of the literature using Medline, PubMed and Web of Science, data provided by the Scientific Registry of Transplant Recipients and the bibliographies of key reviews. We determined a list of key questions and convened a two-day consensus conference to develop summary statements via a series of alternating breakout and plenary sessions. In these sessions, we identified supporting evidence and generated recommendations and/or directions for future research.

Results

Of the 30 questions considered, we found inadequate evidence for the majority of questions and our recommendations were mainly based on expert opinion. There was insufficient evidence to grade three questions, but we were able to develop a consensus definition for acute kidney injury in patients with cirrhosis and provide consensus recommendations for future investigations to address key areas of uncertainty.

Conclusions

Despite a paucity of sufficiently powered prospectively randomized trials, we were able to establish an evidence-based appraisal of this field and develop a set of consensus recommendations to standardize care and direct further research for patients with cirrhosis and renal dysfunction.  相似文献   
994.
Resuscitation of septic patients by means of one or more fluid boluses is recommended by guidelines from multiple relevant organizations and as a component of surviving sepsis campaigns. The technique is considered a key and life-saving intervention during the initial treatment of severe sepsis in children and adults. Such recommendations, however, are only based on expert opinion and lack adequate experimental or controlled human evidence. Despite these limitations, fluid bolus therapy (20 to 40 ml/kg) is widely practiced and is currently considered a cornerstone of the management of sepsis. In this pointof-view critique, we will argue that such therapy has weak physiological support, has limited experimental support, and is at odds with emerging observational data in several subgroups of critically ill patients or those having major abdominal surgery. Finally, we will argue that this paradigm is now challenged by the findings of a large randomized controlled trial in septic children. In the present article, we contend that the concept of large fluid bolus resuscitation in sepsis needs to be investigated further.  相似文献   
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Acute renal failure (now acute kidney injury) is a common complication of critical illness affecting between 30 and 60% of critically ill patients. The development of a consensus definition (RIFLE--risk, injury, failure, loss, end-stage system) has allowed standardization of reporting and epidemiological work. Multicenter multinational epidemiological studies indicate that sepsis is now the most common cause of acute renal failure in the intensive care unit (ICU) followed by cardiac surgery-associated acute kidney injury. Unfortunately, our understanding of the pathogenesis of acute renal failure in these settings remains limited. Because of such limited understanding, no reproducibly effective therapies have been developed. In addition the diagnosis of acute renal failure still rests upon the detection of changes in serum creatinine, which only occur if more than 50% of glomerular filtration is lost and are often delayed by more than 24 hours. Such diagnostic delays make the implementation of early therapy nearly impossible. In response to these difficulties, there has been a concerted effort to use proteomics to identify novel early biomarkers of acute renal failure. The identification and study of neutrophil gelatinase- associated lipocalin has been an important step in this field. Another area of active interest and investigation relates to the role of intravenous fluid resuscitation and fluid balance. Data from large observational studies and randomized, controlled trials consistently indicate that a positive fluid balance in patients with acute renal failure represents a major independent risk factor for mortality and provides no protection of renal function. The pendulum is clearly swinging away from a fluid-liberal approach to a fluid-conservative approach in these patients. Finally, there is a growing appreciation that acute renal failure may identify patients who are at increased risk of subsequent chronic renal dysfunction and mortality, opening the way to post-ICU interventional trials.  相似文献   
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999.
Evidence-based medicine integrates the best available data in decision making, with the goal of minimizing physicians' and patients' subjectivity. In 2006, the American Society of Clinical Oncology edited clinical practice guidelines for the use of larynx preservation strategies. The objective of this review was to evaluate the current levels of evidence for glottic squamous cell carcinoma. Current guidelines for early stage glottic cancer are based on low-level evidence. Conservation surgery (open or transoral) and radiation therapy are all valid options for T1 and selected T2 lesions. For advanced lesions, surgery and combined chemotherapy and radiation are options. High-level evidence favors combined chemotherapy and radiation therapy or altered fractionation radiation therapy as nonsurgical strategies for organ preservation, compared with radiation therapy alone. The optimal combination of chemotherapy, targeted therapy, and radiation therapy remains to be demonstrated, however, and for high-volume tumors, total laryngectomy may still be warranted.  相似文献   
1000.
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