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71.
72.
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   
75.

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   
76.
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   
77.
78.
ObjectiveTo evaluate the association between bezafibrate, a drug used to treat hypertriglyceridemia, and long-term cancer incidence in patients with coronary artery disease (CAD).Patients and MethodsThe study comprised 2980 patients with CAD (mean age, 60 years; 2729 [91.6%] men) who were free of cancer and were enrolled in the Bezafibrate Infarction Prevention study, a double-blind trial conducted between May 1, 1990, and January 31, 1993, in 18 cardiology departments in Israel. Patients randomized to receive 400 mg of bezafibrate (n=1486) or placebo (n=1494) daily for a median of 6.2 years (range, 4.7-7.6 years) were followed up for incidence of cancer through the Israeli National Cancer Registry and all-cause death through the Population Registry of the State of Israel until December 31, 2013. Cox proportional hazards and Fine and Gray survival models were used to assess the bezafibrate-cancer association.ResultsClinical characteristics and laboratory values were well balanced between the 2 groups at the study entry. Over a median follow-up of 22.5 years (range, 21.2-23.9 years), cancer developed in 753 patients. With death considered a competing event, the cumulative incidence of cancer at the end of the follow-up was lower in the bezafibrate vs the placebo group (23.9%; 95 CI, 21.9%-26.1% vs 27.2%; 95 CI, 25.1%-29.4%; P=.04). The hazard ratio for cancer in the bezafibrate vs placebo groups was 0.86 (95% CI, 0.74-0.99). In mediation analysis, the association between bezafibrate treatment and cancer incidence was not sensitive to adjustment for on-trial lipid levels but was attenuated on adjustment for on-trial fibrinogen levels.ConclusionBezafibrate treatment is associated with reduced risk of cancer among patients with CAD. Fibrinogen, but not lipid lowering, is linked to this association.  相似文献   
79.
80.

Background

Subglottic stenosis (SGS) is the most common congenital and/or acquired laryngotracheal anomaly requiring tracheotomy in infants. We sought to determine factors associated with a greater likelihood of tracheotomy in symptomatic infants with SGS who underwent laryngotracheoplasty (LTP).

Methods

Retrospective case series with chart review of patients undergoing single-stage LTP for SGS over a 10-year period (2001–2010) in a tertiary-care pediatric hospital.

Results

Twenty-two children (15 boys, 7 girls), with a mean gestational age of 32.5 weeks, underwent LTP with and without interpositional grafting, at a median age of 89 days. Ten patients (43%) required postoperative tracheotomy. Of patients weighing < 2.5 kg, 7 of 8 eventually required tracheotomy, while none weighing > 5 kg needed tracheotomy (p = 0.003). The average length of stay for patients with a tracheotomy was 125 days, while those without tracheotomy required only 58 days (p = 0.011). The grade of SGS (p = 0.809), gender (p = 0.968), age at surgery (p = 0.178), and gestational age (p = 0.117) were not significantly associated with the need for tracheotomy. Weight at surgery was significantly correlated with the likelihood of needing tracheotomy (p = 0.003).

Conclusions

Patients who weighed less than 2.5 kg at the time of LTP procedures were more likely to require a postoperative tracheotomy. Children who required tracheotomy had longer lengths of hospital stay.  相似文献   
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