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31.
A southern Australian Phorbas species has yielded a novel diterpene, phorbasin A (1), possessing an unprecedented carbon skeleton. The structure for phorbasin A was determined by detailed spectroscopic analysis.  相似文献   
32.

Introduction

Most cochlear implants are currently compatible with magnetic resonance imaging (MRI) up to 3?T. Nevertheless, this does not completely eliminate the risk of serious accidents. Implant displacements and other adverse events with compatible implants have been reported in the literature.

Case reports

Among the six patients who had MRI after receiving implants at our center, we report three cases with adverse events related to the examination. The first case was complicated by magnet displacement with partial demagnetization. The second case showed total demagnetization, which necessitated removal and reimplantation of the implant. The third case involved severe pain sensation which disrupted the MRI scan. The smallest artifact was found with 3D MRI angiography, and largest artifact was found with diffusion and T2 FLASH.

Discussion

Moving the patient into the MRI apparatus must be supervised by an otorhinolaryngology specialist or an experienced radiologist. It is important to consider the magnetic field directions, so that angle between the implant magnetic fields and the MRI B0 always remains less than or equal to 90°. In addition, we recommend the use of an “arrow drawing” to facilitate the orientation of the magnetic field directions. Furthermore, to prevent magnet displacement, we recommend systematic use of a protective splint in addition to bandaging.  相似文献   
33.
Coagulase-negative staphylococci, with the leading species Staphylococcus epidermidis, are the predominant cause of hospital-acquired infections. Treatment is especially difficult owing to biofilm formation and frequent antibiotic resistance. However, virulence mechanisms of these important opportunistic pathogens have remained poorly characterized. Here we demonstrate that S. epidermidis secretes poly-gamma-DL-glutamic acid (PGA) to facilitate growth and survival in the human host. Importantly, PGA efficiently sheltered S. epidermidis from key components of innate host defense, namely antimicrobial peptides and neutrophil phagocytosis, and was indispensable for persistence during device-related infection. Furthermore, PGA protected S. epidermidis from high salt concentration, a key feature of its natural environment, the human skin. Notably, PGA was synthesized by all tested strains of S. epidermidis and a series of closely related coagulase-negative staphylococci, most of which are opportunistic pathogens. Our study presents important novel biological functions for PGA and indicates that PGA represents an excellent target for therapeutic maneuvers aimed at treating disease caused by S. epidermidis and related staphylococci.  相似文献   
34.
Long-term treatment of restless legs syndrome with dopamine agonists   总被引:1,自引:0,他引:1  
BACKGROUND: Controlled clinical trials robustly demonstrate the short-term efficacy of dopamine agonists (DA) for restless legs syndrome (RLS), but little is known about the long-term efficacy and long-term adverse events. Augmentation-an increase in the duration, intensity, and anatomy of RLS symptoms-is commonly associated with dopaminergic treatments; however, risk factors for this troubling scenario have not been formally evaluated. OBJECTIVES: To evaluate the long-term efficacy and tolerability of DA for RLS and to evaluate factors that could predict the occurrence of augmentation. METHODS: We queried all subjects seen from 1996 to 2003 and followed up those initiated on any DA by the Baylor College of Medicine Movement Disorders Clinic, Houston, Tex. Patients with Parkinson disease, uremia, or medications that could affect RLS were excluded. Demographics, efficacy, dosing, adverse events, and augmentation were tracked across time. Statistical modeling was used to evaluate for factors that could predict augmentation. RESULTS: After eliminating all patients with RLS who had factors that could affect DA dosing or the accuracy of data, we observed 83 subjects with at least 6 months' use of DA (mean +/- SD, 39.2 +/- 20.9 months). Efficacy was maintained across time but at the expense of moderate but significant increases in doses (P<.01). Adverse events were frequent but usually mild and seldom resulted in discontinuation. Augmentation was frequent (48% of subjects) but usually modest, and it was predicted by a positive family history for RLS and especially the lack of any neuropathy on electromyographic or nerve conduction velocity tests. CONCLUSIONS: Dopamine agonists continued to effectively treat RLS without long-term adverse events but often required adjustments across time. The higher rate of augmentation in familial and nonneuropathic RLS should be considered when initiating therapy.  相似文献   
35.
OBJECTIVE: This open-label study evaluated the efficacy and tolerability of lamotrigine monotherapy compared with monotherapy with conventional antiepileptic drugs in patients converting from previous monotherapy because of inadequate seizure control or unacceptable side effects. METHODS: This study was conducted in 26 neurology clinics and epilepsy centers throughout the United States. The study enrolled 115 patients with epilepsy converting from previous monotherapy because of inadequate seizure control or unacceptable side effects. Patients were randomized 1:1 to receive 24 weeks of lamotrigine monotherapy or monotherapy with a conventional antiepileptic drug (carbamazepine, phenytoin, or valproate based on physician's choice). Patients were converted during an 相似文献   
36.
Premonitory sensory phenomenon in Tourette's syndrome.   总被引:3,自引:0,他引:3  
We administered a questionnaire designed to probe for premonitory sensations associated with motor tics to 50 patients with Tourette's syndrome (TS). Premonitory sensations were reported by 46 (92%) patients, and the most common sensation was an urge to move and an impulse to tic ("had to do it"). Intensification of premonitory sensations, if prevented from performing a motor tic, was reported also in 37 patients (74%), 36 patients (72%) reported relief of premonitory sensations after performing the tic, and 27 of 40 (68%) described a motor tic as a voluntary motor response to an involuntary sensation, rather than a completely involuntary movement. The "just right" sensation correlated with the presence of co-morbid obsessive-compulsive disorder. We conclude that premonitory sensations are an important aspect of motor tics and some patients perceive motor tics as a voluntary movement in response to an involuntary sensation.  相似文献   
37.
Vegetables and fruits provide an array of microchemicals in the form of vitamins and secondary metabolites (phytochemicals) that may lower the risk of chronic disease. Tracing these phytochemicals at physiologic concentrations has been hindered by a lack of quantitative sensitivity for chemically equivalent tracers that could be used safely in healthy people. Accelerator mass spectrometry is a relatively new technique that provides the necessary sensitivity (in attomoles) and measurement precision (<3%) towards 14C-labeled phytochemicals for detailed kinetic studies in humans at dietary levels.  相似文献   
38.
To estimate seroprevalence of severe acute respiratory syndrome 2 (SARS-CoV-2) among healthcare, first response, and public safety personnel, antibody testing was conducted in emergency medical service agencies and 27 hospitals in the Detroit, Michigan, USA, metropolitan area during May–June 2020. Of 16,403 participants, 6.9% had SARS-CoV-2 antibodies. In adjusted analyses, seropositivity was associated with exposure to SARS-CoV-2–positive household members (adjusted odds ratio [aOR] 6.18, 95% CI 4.81–7.93) and working within 15 km of Detroit (aOR 5.60, 95% CI 3.98–7.89). Nurse assistants (aOR 1.88, 95% CI 1.24–2.83) and nurses (aOR 1.52, 95% CI 1.18–1.95) had higher likelihood of seropositivity than physicians. Working in a hospital emergency department increased the likelihood of seropositivity (aOR 1.16, 95% CI 1.002–1.35). Consistently using N95 respirators (aOR 0.83, 95% CI 0.72–0.95) and surgical facemasks (aOR 0.86, 95% CI 0.75–0.98) decreased the likelihood of seropositivity.  相似文献   
39.
Healthcare personnel are recognized to be at higher risk for infection with severe acute respiratory syndrome coronavirus 2. We conducted a serologic survey in 15 hospitals and 56 nursing homes across Rhode Island, USA, during July 17–August 28, 2020. Overall seropositivity among 9,863 healthcare personnel was 4.6% (95% CI 4.2%–5.0%) but varied 4-fold between hospital personnel (3.1%, 95% CI 2.7%–3.5%) and nursing home personnel (13.1%, 95% CI 11.5%–14.9%). Within nursing homes, prevalence was highest among personnel working in coronavirus disease units (24.1%; 95% CI 20.6%–27.8%). Adjusted analysis showed that in hospitals, nurses and receptionists/medical assistants had a higher likelihood of seropositivity than physicians. In nursing homes, nursing assistants and social workers/case managers had higher likelihoods of seropositivity than occupational/physical/speech therapists. Nursing home personnel in all occupations had elevated seropositivity compared with hospital counterparts. Additional mitigation strategies are needed to protect nursing home personnel from infection, regardless of occupation.  相似文献   
40.
Objective The aim of this study was to provide a pharmacy service to improve continuity of patient care across the primary‐secondary care interface. Setting The study involved patients discharged from two acute‐care tertiary teaching hospitals in Melbourne, Australia, returning to independent living. Methods Consecutive patients admitted to both hospitals who met the study criteria and provided consent were recruited. Recruited patients were randomised to receive either standard care (discharge counselling, provision of compliance aids and communication with primary healthcare providers when necessary) or the intervention (standard care and a home visit from a community liaison pharmacist (CLP) within 5 days of discharge). Participant medication was reviewed during the visit according to set protocols and compliance and medication understanding was measured. All participants were telephoned 8–12weeks after discharge to assess the impact of the intervention on adherence and medication knowledge. Key findings The CLP visited 142 patients with a mean time of 4.2 days following hospital discharge (range = 1–14 days). Consultations lasted 15–105 min (mean, 49 min; SD, ± 21 min). The CLPs retrospectively coded 766 activities and interventions that occurred during home visits, subsequently categorised into three groups: counselling and education, therapeutic interventions and other interventions. No statistical difference was detected in the number of medications patients reported taking at follow‐up: the mean value was 7.72 (SD, ± 3.27) for intervention patients and 7.55 (SD, ± 3.27) for standard‐care patients (P = 0.662). At follow‐up self‐perceived medication understanding was found to have improved in intervention patients (P < 0.001) and significant improvements from baseline in medication adherence were found in both standard‐care (P < 0.022) and intervention (P < 0.005) groups; however, adherence had improved more in intervention patients. Conclusion The community liaison pharmacy service provided critical and useful interventions and support to patients, minimising the risk of medication misadventure when patients were discharged from hospital to home.  相似文献   
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