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991.

Background

Pain is one of the most common reasons for emergency department (ED) visits in the United States. Ketamine is a sedative with N-methyl-D-aspartate (NMDA) receptor antagonism. Recent literature has suggested that the use of subdissociative dose ketamine (SDDK) may be safe and effective for acute pain.

Objective

The objective of our study was to evaluate ketamine in subdissociative doses as an adjunct for acute pain in the ED.

Methods

This was a single-center, prospective, randomized, double-blind, placebo-controlled trial that evaluated the use of SDDK in adult patients who presented to the ED with acute pain. Patients received ketamine 0.3 mg/kg via intravenous piggyback over 15 min or placebo. Morphine 0.1 mg/kg intravenous push was administered with the study interventions. The primary outcome was the patient's pain score 15 min after initiation of the intervention. Secondary outcomes included adverse events, consumption of rescue analgesia, patient's length of stay, and patient satisfaction with treatment.

Results

Thirty patients were enrolled in each group. Median pain scores in patients who received ketamine were lower than in controls at 15 min (3.5 [interquartile range {IQR} 1.0–7.3 vs. 6.0 [IQR 4.0–9.0], respectively; p = 0.018). No serious adverse events occurred. No difference was detected in the amount of rescue analgesia used or in length of stay. Patients who received ketamine reported a higher mean satisfaction score with their pain management (8.57 [standard deviation {SD} 2.1]) than patients who received placebo (6.05 [SD 2.6]; p = 0.01).

Conclusion

When used as an adjunct, SDDK administered at 0.3 mg/kg over 15 min resulted in safe and effective analgesia for ≤30 min in patients who presented with acute pain in the ED.  相似文献   
992.
This study piloted a hospital‐based delirium and falls education program to investigate the impacts on staff knowledge and practice plus patient falls. On a medical ward, staff knowledge was compared before and after education sessions. Other data – collected a day before and after program implementation – addressed documentation of patients' delirium and evidence of compliance with falls risk minimization protocols. These data, and numbers of patient falls, were compared before and after program implementation. Almost all ward staff members participated in education sessions (7 doctors, 7 allied health practitioners, and 45 nurses) and knowledge was significantly improved in the 22 who completed surveys both before and after session attendance. Patients assessed as having delirium (5 before implementation, 4 afterwards) were all documented as either confused or delirious. Small changes eventuated in adherence with falls risk management protocols for confused patients and the number of falls decreased. The program merits a stronger emphasis on staff activities relating to the detection, documentation, and management of delirium to inter‐professional roles and communication. Evidence of practice enhancement from program implementation should precede rigorous testing of impacts upon falls.  相似文献   
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BACKGROUND AND OBJECTIVES: Diverse vascular effects have been ascribed to vasopressin, including the potential to cause vasodilation, vasoconstriction, and nitric oxide release. The objective of this study was to establish the pharmacodynamics, reproducibility, and nitric oxide dependence of the vasomotor actions of vasopressin in the forearm resistance vessels. METHODS: Blood flow in both forearms of 12 healthy men was measured with venous occlusion plethysmography. Continuous and discontinuous doses of 1 to 300 pmol/min vasopressin were administered by the intrabrachial route. For assessment of the contribution of nitric oxide, vasopressin was coadministered with a "nitric oxide clamp," a balanced coinfusion of 4 micromol/min L-N(G)-monomethylarginine (a nitric oxide synthase inhibitor) and 0.3 to 0.8 nmol/min sodium nitroprusside (an exogenous nitric oxide donor) to block endogenous nitric oxide production and restore normal basal blood flow, respectively. RESULTS: Vasopressin produced a dose-dependent biphasic change in blood flow with a maximum reduction in percentage change in blood flow ratio of infused and control arms of 22% +/- 5% at 3 pmol/min (P <.01) and an increase of 80% +/- 30% at 300 pmol/min (P <.01). There were no significant differences in repeated responses obtained either within or between days. Repeated discontinuous dosing did not change the magnitude of the maximum vasoconstriction or vasodilation, but prolonged continuous infusion produced maximal vasodilation at 12 minutes that subsequently resulted in substantial tachyphylaxis (P =.04). Although there was no augmentation of vasoconstriction, the nitric oxide clamp abolished vasopressin-induced vasodilation (P <.05). CONCLUSIONS: Intra-arterial vasopressin causes a reproducible dose-dependent biphasic change in forearm blood flow. Vasomotor responses are time-dependent with a modest delay to peak vasodilation and tachyphylaxis with prolonged sustained infusion. Nitric oxide release is a major contributor to vasopressin-induced vasodilation but does not directly oppose low-dose vasopressin-induced vasoconstriction.  相似文献   
995.
To determine whether Pteropine orthoreovirus (PRV) exposure has occurred in Singapore, we tested 856 individuals from an existing serum panel collected from 2005-2013. After an initial screen with luciferase immunoprecipitation system and secondary confirmation with virus neutralization test, we identified at least seven individuals with specific antibodies against PRV in both assays. Our findings confirm that PRV spillover into human populations is relatively common in this region of the world.  相似文献   
996.

Schistosomiasis is a tropical neglected disease whose socioeconomic impact is surpassed only by malaria. Until recently, praziquantel (PZQ) has been the only available drug, raising concerns that tolerant/resistant strains may appear. Since the discovery of the schistosomicidal potential of artemisinin (ART), new derivatives have been produced and evaluated. In this work, we evaluated the activity of ART derivatives against Schistosoma mansoni, both in vitro and in vivo. In the in vitro assay, worm survival, oviposition, and morphological alterations were evaluated. Further analysis of morphological alterations and membrane integrity was conducted using scanning electron microscopy and a cell-permeable, benzimidazole dye (Hoescht 33258) that binds to the minor groove of double stranded DNA. For the in vivo assay, artesunic acid (AcART) and dihydroartemisinin acetate (AcDQHS) were selected, since they showed the best in vitro results. Infected mice treated 21, 45, or 60 days post-infection (dpi), with a concentration of 100 mg/kg of either AcART or AcDQHS, showed a significant worm reduction (particularly in females), fewer eggs eliminated in feces, and a decrease of immature eggs in the intestinal tissues. Our results indicate that AcART and AcDQHS have some schistosomicidal activity against juvenile and adult stages of S. mansoni.

  相似文献   
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998.
999.
In this paper, an effective dynamical EIT imaging scheme is presented for on-line monitoring of the abruptly changing resistivity distribution inside the object, based on the interacting multiple model (IMM) algorithm. The inverse problem is treated as a stochastic nonlinear state estimation problem with the time-varying resistivity (state) being estimated on-line with the aid of the IMM algorithm. In the design of the IMM algorithm multiple models with different process noise covariance are incorporated to reduce the modeling uncertainty. Simulations and phantom experiments are provided to illustrate the proposed algorithm.  相似文献   
1000.
Lateral epicondylitis (LE) is difficult to manage and can result in significant patient morbidity. Currently, the clinical use of platelet‐rich plasma (PRP) for painful tendons has received attention, but its efficacy remains controversial. This study aimed to investigate the clinical effects of PRP and its biological components. A total of 156 patients with LE were randomly divided into group 1, treated with a single injection of 2‐ml autologous PRP, and group 2, treated with a control received only physical therapy without injection. Both groups used a tennis elbow strap and performed stretching and strengthening exercises during 24 weeks’ follow‐up. Pain and functional improvements were assessed using the visual analog scale (VAS), Modified Mayo Clinic Performance Index for the elbow, and magnetic resonance imaging (MRI). White blood cell count, platelet count, and levels of platelet‐derived growth factor‐AB (PDGF‐AB), PDGF‐BB, transforming growth factor‐β (TGF‐β), vascular endothelial growth factor, epithelial growth factor, and interleukin‐1 β in PRP were measured and investigated for statistical correlation with the clinical score. At 24 weeks, all pain and functional variables, including VAS score, Mayo Clinic performance scores, and MRI grade, improved significantly in group 1 (p < 0.05). PDGF‐AB, PDGF‐BB, and TGF‐β levels were more significantly increased in PRP than in whole blood. TGF‐β level significantly correlated with Mayo Clinic performance score and MRI grade improvement. Thus, TGF‐β level in PRP is considered to play a pivotal role in tendon healing. These results may contribute to identifying the best protocol for PRP application in tendinopathies. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:913–920, 2018.
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