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991.

Background  

Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability.  相似文献   
992.
FDA’S Perspectives on Cardiovascular Devices   总被引:1,自引:0,他引:1  
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug & Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular device in a U.S. clinical trial.  相似文献   
993.
994.
Abstract:  In Sweet's syndrome, the essential features are the characteristic morphology of the lesions, their histologic appearance, the dramatic response to corticosteroids and the absence of scarring. We report an 8-month-old infant in whom Sweet's syndrome was diagnosed and who developed acquired cutis laxa in the skin lesions.  相似文献   
995.
996.
997.

Introduction  

Ethanol has a suppressive effect on inflammation and the immune system, but the effect of ethanol on tendon healing in vivo has not been studied. The purpose of this study was to investigate the histological and biomechanical effects of ethanol intake on tendon healing in a rat tendon injury model.  相似文献   
998.
999.

Objectives

For individuals not on antiretroviral therapy, the risk of heterosexual transmission of HIV appears negligible when blood plasma (BP) viral loads are <1500 HIV‐1 RNA copies/mL. It is not clear whether this observation can be extrapolated to individuals on highly active antiretroviral therapy (HAART). Because of differential tissue penetration, antiretroviral drug concentrations may be sufficient to maintain an undetectable viral load in the BP yet not achieve adequate levels to suppress HIV in the genital tract. Therefore, we wanted to correlate HIV viral loads and drug concentrations in semen plasma (SP) and BP.

Methods

Thirty‐three men were included. All were on combination antiretroviral therapy with an undetectable BP viral load for at least 1 year. Blood and semen samples were collected within 2 h of each other and tested for HIV RNA by the NucliSens QT (bioMerieux, St Laurent, QC, Canada) method; drug concentrations were determined by liquid chromatography tandem mass spectrometry.

Results

Two of the 33 patients (6.1%) with BP viral loads below detection had time‐matched HIV viral loads in SP ≥700 copies/mL. Both patients were on efavirenz, the SP concentrations of which were ≤10% of the levels in BP and well below the minimal therapeutic drug monitoring target concentration required to suppress HIV.

Conclusions

Because, at least in part, of poor drug penetration into the genital tract, an undetectable HIV viral load in the BP does not guarantee an undetectable viral load in semen. In view of this, caution should be taken in concluding that patients on HAART with suppressed viraemia are sexually non‐infectious.  相似文献   
1000.
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