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101.
National intercomparisons of activity measurements of 131I, a radioisotope widely used for diagnosis and therapy of thyroid related ailments, were initiated in 1979 as a quality assurance program, towards improving radiation safety procedures and related dosimetry in Nuclear Medicine Centres (NMCs) in India. Oral administration of a known quantity of radioiodine to patients requires accurate radioactivity measurements to be performed on a well-calibrated isotope calibrators. Under or over estimation of the activity due to a faulty or uncalibrated isotope calibrator could provide misleading results. Calibration of isotope calibrators and the traceablity of subsequent measurements to the national standards laboratory is one of the essential basic radiation safety requirement of the IAEA. In view of the stringent quality assurance requirements for activity measurements imposed by Atomic Energy Regulatory Board, a National Intercomparison Program was initiated and to date ten such intercomparison programs have been conducted by the Radiation Safety Systems Division, of the Bhabha Atomic Research Centre. This program has benefited the participants by making their measurements traceable to the National Primary Standards. Over the years there has been a marked increase in the number of NMCs participating in the intercomparison programs. As a result, the number of institution showing large deviation from the correct value has decreased considerably over the years. This program thus, has enabled participating NMCs to check their isotope calibrators so as to ensure proper delivery of radiation dose to the patients and hence to optimise patient exposure.  相似文献   
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Objectives. We aimed to assess the spontaneous healing of myocardial function after occlusion of a chronically stenosed coronary vessel in a porcine model. Design. Ischemia and infarction was produced by Ameroid constrictor placement and a subsequent ligation of the left circumflex artery. Cardiac MRI and 18FDG-PET were performed one and five weeks later. Ki67 staining was used to identify proliferating cells. Results. Restoration of perfusion defect was detected by MRI (p=0.0065), reduced systolic function of the lateral segment spontaneously recovered (p=0.03). There was also a suggestive raise in impaired ejection fraction (p=0.06). Left ventricular early diastolic filling and peak filling rate were substantially improved (p=0.039 and p=0.0078). Scar size reduced (p=0.03). On the 18FDG-PET, deranged metabolism was alleviated (p=0.03). Cardiomyocytes with positive Ki-67 staining were located principally in the non-infarcted myocardium as compared to the infarction or border areas (p=0.037). Conclusions. We demonstrated spontaneous functional healing of ischemic and infarcted left ventricle, suggesting border zone perfusion recovery. Scar reduction was detected. Different pattern of myocyte proliferation between infarction and non-ischemic myocardium was seen.  相似文献   
104.
Study Objective1) To quantify the incidence and severity of postdischarge nausea and vomiting (PDNV) for 7 days in adults undergoing outpatient surgeries with general anesthesia; 2) to evaluate whether a risk model previously developed for the first two postoperative days may be used to predict the patient’s risk of PDNV for 7 days; and 3) to verify whether the same risk factors are applicable in the 3 to 7 day period.DesignProspective study.SettingTwo university-affiliated centers.Patients248 adult (> 18 years) surgical outpatients undergoing ambulatory surgical procedures with general anesthesia between 2007 and 2008.MeasurementsThe incidence and severity of PDNV and a simplified risk score for PDNV was assessed prospectively from discharge up to 7 postoperative days.Main ResultsThe overall incidence of nausea was 56.9% and of emesis was 19.4%. The incidence of PDNV was highest on the day of surgery (DOS), with PDNV of 44.8% and decreasing over time to 6.0% on day 7. Using the simplified risk score for PDNV the area under the receiver operating characteristic (ROC) curve was 0.766 (0.707, 0.825). A previous history of postoperative nausea and vomiting (PONV; OR 3.51, CI 1.70 - 7.27), operating room time (odds ratio [OR] 2.19, 95% CI 1.34 - 3.60), use of ondansetron in the Postanesthesia Care Unit (PACU; OR 6.39, CI 1.65-24.79), and pain during days 3–7 (OR 1.67, CI 1.30 - 2.14) were the strongest predictors of PDNV on days 3–7.ConclusionsPDNV affects a significant number of patients after ambulatory surgery, and our simplified PDNV score may be applied to a 7-day population. Pain appears to be a factor in late PDNV. It is possible that the presence of PDNV during days 3–7 has different origins from the PDNV that resolved over the first 48 hours.  相似文献   
105.
Lasers in Medical Science - Hyposalivation is a condition represented by a reduced salivary flow and may include symptoms such as mouth dryness (xerostomia), loss of taste, pain, dysphagia, and...  相似文献   
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Background

There is a lack of studies about procedural sedation of alcoholics. Dexmedetomidine is recommended for procedural sedation and reported effective for alcohol withdrawal. We evaluated the suitability of dexmedetomidine for sedation of alcoholics during endoscopic retrograde cholangiopancreatography (ERCP).

Methods

Fifty patients with chronic alcoholism scheduled for elective ERCP were randomized 1:1 to receive dexmedetomidine (Dex group) (loading dose 1 μg kg?1 over 10 min, followed by constant intravenous infusion 0.7 μg kg?1 h?1) or saline placebo (P group). Patient-controlled sedation with propofol–alfentanil was used by patients as a rescue method. Sedation was considered as successful if no intervention of an anesthesiologist was needed. Consumption of sedatives was registered, and sedation levels and vital signs were monitored.

Results

Dexmedetomidine alone was insufficient in all patients. The mean ± SD consumption of propofol was 159 ± 72 mg in the P group, and 116 ± 61 mg in the Dex group (p = 0.028). Sedation was successful in 19 of 25 (76 %) patients in the Dex group and in all patients in the P group (p = 0.022). The incidence of sedation adverse events did not differ between the groups. Dexmedetomidine was associated with delayed recovery.

Conclusions

Patient-controlled sedation with propofol and alfentanil but not dexmedetomidine can be recommended for sedation of alcoholics during ERCP.  相似文献   
108.
Low health-related quality of life (HRQOL) has been associated with increased risk for hospitalization and death in ESRD. However, the relationship of HRQOL with outcomes in predialysis CKD is not well understood. We evaluated the association between HRQOL and renal and cardiovascular (CV) outcomes in 1091 African Americans with hypertensive CKD enrolled in the African American Study of Kidney Disease and Hypertension (AASK) trial and cohort studies. Outcomes included CKD progression (doubling of serum creatinine/ESRD), CV events/CV death, and a composite of CKD progression or death from any cause (CKD progression/death). We assessed HRQOL, including mental health composite (MHC) and physical health composite (PHC), using the Short Form-36 survey. Cox regression analyses were used to assess the relationship between outcomes and five-point decrements in MHC and PHC scores using measurements at baseline, at the most recent annual visit (time-varying), or averaged from baseline to the most recent visit (cumulative). During approximately 10 years of follow-up, lower mean PHC score was associated with increased risk of CV events/CV death and CKD progression/death across all analytic approaches, but only time-varying and cumulative decrements were associated with CKD progression. Similarly, lower mean MHC score was associated with increased risk of CV events/CV death regardless of analytic approach, while only time-varying and cumulative decrements in mean MHC score was associated with CKD progression and CKD progression or death. In conclusion, lower HRQOL is associated with a range of adverse outcomes in African Americans with hypertensive CKD.  相似文献   
109.
This study investigates narratives of Finnish children with specific language impairment (SLI) from linguistic and pragmatic perspectives, in order to get a comprehensive overview of these children’s narrative abilities. Nineteen children with SLI (mean age 6;1 years) and 19 typically developing age-matched children participated in the study. Their picture-elicited narrations were analysed for linguistic productivity and complexity, grammatical and referential accuracy, event content, the use of mental state expressions and narrative comprehension. Children with SLI showed difficulties in every aspect of narration in comparison to their peers. Only one measure of productivity, the number of communication units, did not reach statistical significance. Not only was linguistic structure fragile but also pragmatic aspects of storytelling (referencing, event content, mental state expressions and inferencing) were demanding for children with SLI. Results suggest that pragmatic aspects of narration should be taken into account more often when assessing narrative abilities of children with SLI.  相似文献   
110.
Meningioangiomatosis (MA) is an uncommon brain tumor. The role of imaging techniques is underscored in cases where the tumor location makes resection (or even biopsy) dangerous. We report the case of a child with an MA tumor located deep in the right sylvian fissure. A computed tomography (CT) scan showed calcifications in a highly vascular lesion with surrounding edema. Magnetic resonance spectroscopy (MRS) showed a distinct choline (Cho) peak, which usually suggests a proliferating tumor. Fluorodeoxyglucose positron emission tomography (FDG‐PET) showed the lesion lacked hypermetabolic features. These radiological features should put MA in the differential diagnosis. Pediatr Blood Cancer 2009;53:672–674. © 2009 Wiley‐Liss, Inc.  相似文献   
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