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71.

Objective

Seasickness may impose severe limitations on the performance of ships’ crew. Cervical vestibular evoked myogenic potentials (cVEMP) assess the function of the saccule, the organ responsible for monitoring vertical linear acceleration, which has been found to be the most provocative motion stimulus in the evolution of motion sickness. We used the cVEMP test in a prospective evaluation of susceptibility and habituation to seasickness.

Methods

Forty-six naval recruits underwent the cVEMP test before exposure to sea conditions. After 6 months’ sailing experience, participants completed a questionnaire evaluating their initial and current seasickness severity. Based on their most recent experience, subjects were divided into three groups: non-vomiting non-habituating (NV-NH), vomiting (V), and non-vomiting habituating (NV-H).

Results

Statistically significant lower thresholds for cVEMP were found in subjects who habituated to sea conditions (NV-H), compared with those remaining severely susceptible (V) (77.0 dB HL vs. 84.9 dB HL; < 0.01).

Conclusions

The ability to produce the cVEMP at lower thresholds represents a broader dynamic range, in which the reflex can respond to a wider array of stimuli amplitudes.

Significance

The present study demonstrates the potential of the cVEMP test for predicting future habituation to seasickness.  相似文献   
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Since mild traumatic brain injury (mTBI) often leads to neurological symptoms even without clinical MRI findings, our goal was to test whether diffuse axonal injury is quantifiable with multivoxel proton MR spectroscopic imaging (1H-MRSI). T1- and T2-weighted MRI images and three-dimensional 1H-MRSI (480 voxels over 360 cm3, about 30 % of the brain) were acquired at 3 T from 26 mTBI patients (mean Glasgow Coma Scale score 14.7, 18–56 years old, 3–55 days after injury) and 13 healthy matched contemporaries as controls. The N-acetylaspartate (NAA), choline (Cho), creatine (Cr) and myo-inositol (mI) concentrations and gray-matter/white-matter (GM/WM) and cerebrospinal fluid fractions were obtained in each voxel. Global GM and WM absolute metabolic concentrations were estimated using linear regression, and patients were compared with controls using two-way analysis of variance. In patients, mean NAA, Cr, Cho and mI concentrations in GM (8.4 ± 0.7, 6.9 ± 0.6, 1.3 ± 0.2, 5.5 ± 0.6 mM) and Cr, Cho and mI in WM (4.8 ± 0.5, 1.4 ± 0.2, 4.6 ± 0.7 mM) were not different from the values in controls. The NAA concentrations in WM, however, were significantly lower in patients than in controls (7.2 ± 0.8 vs. 7.7 ± 0.6 mM, p = 0.0125). The Cho and Cr levels in WM of patients were positively correlated with time since mTBI. This 1H-MRSI approach allowed us to ascertain that early mTBI sequelae are (1) diffuse (not merely local), (2) neuronal (not glial), and (3) in the global WM (not GM). These findings support the hypothesis that, similar to more severe head trauma, mTBI also results in diffuse axonal injury, but that dysfunction rather than cell death dominates shortly after injury.  相似文献   
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It is plausible that infections post‐hematopoietic SCT play a role in the pathogenesis of BOS. A prospective study for children with history, questionnaire, examination, PFTs, and blood counts at one, three, six, nine, 12, 18, and 24 months post‐SCT was conducted. Between September 2009 and September 2011 (n = 39), six developed BOS at 200 days (range 94–282), three patients had probable clinical respiratory infection, and all six had higher neutrophil count compared to non‐BOS patients (4.7 vs. 2.4 at three months and 6.3 vs. 2.9 at six months ×109/L, p = 0.03). Contribution of clinical and subclinical infection needs to be considered in the pathogenesis of BOS.  相似文献   
77.

Background

Professional skills and academic records of the highest degree are essential requirements for the chairmanship of internal medicine departments. Whether the new generation and future successors of Israeli chairmen is endowed with these attributes is not known.

Purpose

To determine whether there is a lack of future suitable successors for the current heads of internal medicine departments in Israel and to compare the demographic, academic and professional characteristics of the older and newer generations of department heads.

Methods

An online anonymous questionnaire was nationally distributed during 2016 to all active heads of internal medicine departments in Israel (n?=?101). First round was followed by two runs of personal phone calls to promote participation.

Results

Sixty-seven (67%) of chairmen responded. The vast majority of current chairs of internal medicine departments are males (N?=?59, 88%) over 50 years of age (N?=?58, 86%) with established academic background with lecturer degree or higher (N?=?57, 85%).Only 19 (28%) of current heads assigned a future successor. Comparison of chairmen who did and did not assigned successors demonstrated that assignment of successors was associated with higher academic status (P?<?0.02) and longer chairmanship (p?<?0.01) but not with mean age of current chairmen (p?<?0.08). Nevertheless, most assignments (55%) were done by chairmen in the 61 to 67 years age group. As compared to current chairmen, the designated successors have lesser academic status (p?<?0.01) and are characterized by a higher female prevalence (P?<?0.03).

Conclusions

Significant demographic, professional and academic differences exist between the current chairs of internal medicine departments in Israeli hospitals and their future successors. This underscores the need for reassessment of the availability and requirements of this crucial position.
  相似文献   
78.

Objectives

To examine whether higher obesity level was associated with extensive staffing assistance (from 2 or more persons) for completing activities of daily living (ADL) among older nursing home residents.

Design

Retrospective cross-sectional study.

Setting

US government–certified nursing homes.

Participants

Medicare beneficiaries residing in a nursing home on April 1, 2015. Exclusion criteria were age less than 65 years and body mass index (BMI) below 18.5 (underweight).

Measures

Residents were divided by obesity level according to established BMI cutoffs, as follows: nonobese (BMI = 18.5-29.9) or mild (BMI = 30.0-34.9), moderate (BMI = 35.0-39.9), or severe (BMI ≥40) obesity. Level of staffing assistance for completing each of 10 ADL (bed mobility, transfer, walking in room, walking in corridor, on- and off-unit locomotion, dressing, eating, toileting, and personal hygiene) was dichotomized as below 2 and 2 or more. Robust Poisson regression was used to test whether obesity conferred excess risk for needing 2 or more staff to complete each ADL. Adjusted models included individual-level covariates and nursing home fixed effects.

Results

A total of 1,063,383 nursing home residents were identified, including 309,263 (29.0%) with obesity. Adjusted relative risks (95% confidence intervals) for 2-person assistance with bed mobility associated with mild, moderate, and severe obesity were 1.17 (1.15, 1.18), 1.28 (1.25, 1.31), and 1.40 (1.36, 1.43), respectively. Adjusted relative risks for 2-person assistance with transferring associated with mild, moderate, and severe obesity were 1.15 (1.13, 1.17), 1.24 (1.22, 1.27), and 1.36 (1.33, 1.39), respectively. Obesity was associated with 2-person assistance for all other ADL except for eating.

Conclusions

Higher obesity level was significantly associated with assistance from 2 or more staff for completing 9 of 10 ADL. Given increasing obesity rates in nursing homes, payment mechanisms that do not adjust for obesity or comprehensively account for excess ADL assistance may need revision to prevent adverse impacts on the long-term care system.  相似文献   
79.
Computed-assisted surgery (CAS) has been designed to improve oral implant planning and positioning and to increase safety and operator comfort. This is especially important in the esthetic zone, at sites with bone deficiency, and when minimally invasive implant placement is the therapy of choice. Current available CAS systems are relatively large and expensive and require a lengthy learning period. This report presents a novel tactile imaging and registration concept that enables the operation of a newly developed computerized implant locating system. An intraoral bone-sounding device maps the surface of the jaw through the soft tissue. Bone contour data are registered over the computerized tomographic image. Guided by treatment preplanning software, a chairside robotic manipulator fabricates guiding sleeves that direct the drill and implant during the osteotomy and implant placement, respectively. The authors' clinical experience shows that tactile registration based the Implant Locating System is simple to use and provides accurate implant design and placement that requires only basic computer experience, minimal operational space, and low infrastructure investment. The system allows final adjustments at the time of operation, transforming each implant surgery into a fully monitored procedure.  相似文献   
80.
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