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PURPOSE: To determine whether 3-dimensional ultrasonography (3D US) provides information about anatomy and position of extraocular muscles to better guide surgeons approaching strabismus in patients with craniosynostosis who often have anomalous or absent eye muscles. METHODS: The 4 rectus eye muscles were imaged using 3D US for 7 children with craniosynostosis before or after strabismus surgery. Reconstructed 3D images were interpreted as having normal or abnormal anatomy and position, based on comparison with images acquired from 6 normal eyes. Interpretation was validated against the intraoperative findings from strabismus surgery. RESULTS: A total of 34 scans from the study group were used for comparison and validation purposes. Accuracy of anatomical assessments was 85% +/- 12% (percentage +/- confidence interval) and of positional assessments was 62% +/- 16%. Sensitivity and specificity of anatomical assessments was 80% +/- 14% and 88% +/- 10%, respectively. Anatomic anomalies detected by 3D US included excessively thick, thin, scarred and fibrotic, and absent muscles. Sensitivity and specificity of positional assessments was 48% +/- 17% and 85% +/- 12%, respectively. Positional anomalies such as muscle displacement off the normal clock hour axis or posteriorly displaced insertion were also detected. CONCLUSIONS: The 3D US may have an adjunctive role in determining anatomy and position of rectus muscles in patients with craniosynostosis, although it was more accurate in assessing anatomic features rather than positional features of rectus muscles.  相似文献   
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The whole-cell patch-clamp technique was used to study the effects of holding potential and frequency on the Ca2+ current in frog ventricular myocytes. INa was blocked by TTX, and ica was activated with depolarizing clamps from different holding potentials. Variation of the holding potential revealed three new effects on ica: (1) At -40 mV iCa declined with a time constant of 15 min, while at -90 mV, this irreversible decline (run down) in iCa did not occur. (2) The decline of iCa at -40 mV was biphasic: run down was preceeded by a slow inactivation with a time constant of 40 s, which was reversible upon returning the holding potential to -90 mV. (3) Increasing the frequency of the clamp pulses from 0.1 to 1 Hz led to a rapid decline of iCa when the holding potential was positive to -60 mV, but at -90 mV had either no effect or increased iCa by 35%, if c-AMP was included in the dialyzing solution. On the other hand, c-AMP did not alter the time course of the run down and the slow inactivation. Replacement of extracellular Ca2+ by Ba2+ markedly slowed iCa kinetics, but did not change the very slow inactivation or the frequency-induced enhancement of iCa. Injection of c-AMP led to a transient increase of iCa. The phosphodiesterase inhibitor theophylline enhanced the amplitude of the transient and slowed its decay. This effect was mimicked by increased frequency. It is concluded that frequency-induced enhancement of iCa is highly dependent on the holding potential, independent of Ca2+, and may involve elevation of the intracellular level of c-AMP via inhibition of phosphodiesterase activity. The new type of very slow inactivation is probably under direct voltage control and independent of Ca2+ and c-AMP.  相似文献   
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Depression commonly overlaps with uremic symptoms, but anxiety is less commonly studied among renal patients. The symptoms of medical illness, along with the psychological and social stresses that often accompany a debilitating chronic disease, are thought to produce deleterious psychological consequences. We sought to determine the prevalence and predictors of anxiety and depression among Saudi dialysis patients in Makkah. A cross-sectional study of anxiety and depression among end-stage renal disease (ESRD) patients in Makkah was conducted in November 2011. The Hospital Anxiety and Depression Scale (HADS) was used to screen for anxiety and depression. Participants’ demographic data, possible stressors and past psychiatric history were obtained. All participants were Saudi ESRD patients on maintenance hemodialysis. According to HADS, 57 (21.1%) patients were probable cases of anxiety and 63 (23.3%) were probable cases of depression. Only 32 (11.3%) were diagnosed with depression or anxiety before ESRD onset. Age was a significant predictor of anxiety and depression diagnoses. Major family problems (p?=?0.001) were also a significant predictor of anxiety. Anxiety and depressive symptoms are prevalent among ESRD patients in Makkah, and anxiety can be predicted by family factors. Early detection, management and family support might improve clinical outcomes.  相似文献   
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The presence of Ornithobacterium rhinotracheale (ORT) in poultry farms in several parts of Iran has been confirmed over the last few years. The purpose of this study was to determine the presence of ORT antibodies by enzyme-linked immunosorbent assay (ELISA) in broiler and broiler breeder chickens in western parts of Iran. In a one-year period, from April 2009 to February 2010, a total of 435 blood samples were collected from 30 commercial chicken flocks (24 broiler flocks and six broiler breeder flocks) located in Kermanshah Province, west of Iran. None of the broilers and broiler breeders have been vaccinated against ORT prior to sampling. The province was divided into four geographical areas: southwest, southeast, northwest, and northeast. Flocks in each area, specifically the birds in each flock, were randomly sampled. The presence of antibodies against ORT in each serum sample was tested twice by ELISA using a commercial kit. The results revealed that 50.1 % broiler and 70.5 % broiler breeder chickens were serologically positive for ORT. Out of 347 serum samples obtained from broiler chickens, 174 (50.1 %) were positive for ORT antibodies, which represented 18 (75.0 %) of 24 examined broiler flocks. A higher rate of seropositivity (71.4 % of samples and 83.3 % of broiler flocks) was observed in the northwest. Out of 88 samples obtained from broiler breeder chickens, 62 (70.5 %) were positive for ORT antibodies, which belonged to six (100 %) of the examined broiler breeder flocks. Detection of anti-ORT antibodies among broiler breeders was significantly higher than that of broilers.  相似文献   
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Mesenchymal stem cells (MSCs) are widespread in adult organisms and may be involved in tissue maintenance and repair as well as in the regulation of hematopoiesis and immunologic responses. Thus, it is important to discover the factors controlling MSC renewal and differentiation. Here we report that adult MSCs express functional Toll-like receptors (TLRs), confirmed by the responses of MSCs to TLR ligands. Pam3Cys, a prototypic TLR-2 ligand, augmented interleukin-6 secretion by MSC, induced nuclear factor kappa B (NF-kappaB) translocation, reduced MSC basal motility, and increased MSC proliferation. The hallmark of MSC function is the capacity to differentiate into several mesodermal lineages. We show herein that Pam3Cys inhibited MSC differentiation into osteogenic, adipogenic, and chondrogenic cells while sparing their immunosuppressive effect. Our study therefore shows that a TLR ligand can antagonize MSC differentiation triggered by exogenous mediators and consequently maintains the cells in an undifferentiated and proliferating state in vitro. Moreover, MSCs derived from myeloid factor 88 (MyD88)-deficient mice lacked the capacity to differentiate effectively into osteogenic and chondrogenic cells. It appears that TLRs and their ligands can serve as regulators of MSC proliferation and differentiation and might affect the maintenance of MSC multipotency.  相似文献   
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Background: The steady rise in the number of critically ill patients in the USA has led to an increase in the need for tracheostomies in patients requiring chronic ventilatory support. There is a matched need for experienced operators to safely and efficiently perform these procedures. Objectives: We evaluated the effects on procedural outcomes and efficiency of percutaneous dilatational tracheostomy (PDT) placement in the medical intensive care unit (MICU) by the surgical team (ST) or interventional pulmonologists (IP). The IP team joined the PDT team in September 2007 and became primarily responsible for all PDT in the MICU. Methods: A retrospective analysis of prospectively collected data of patients who received PDT in the MICU by ST and IP from September 2007 to August 2010 was made. Outcomes including safety, efficacy, and procedural efficiency were compared. Results: One hundred seven patients underwent bedside PDT in the MICU during this period. Forty-three procedures (40.2%) were performed by the ST and 64 procedures (59.8%) were performed by IP. There was no statistical difference between the incidence of airway injury and infection between the two procedural groups. There were no deaths related to the performance of PDT in our series. PDT was completed within 48 h of request in 100% of IP patients and 95% of ST patients (p = 0.08). Conclusions: There were no statistical differences in PDT between the ST and IP groups when comparing complications. There was a trend towards an increased efficiency in time to PDT after consultation within the IP PDT group. Trained IP can safely and effectively perform PDT.  相似文献   
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