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991.
Bladder calculi in elderly are thought to be commonly associated with presence of bladder outlet obstruction. However there is a role of systemic factors in pathogenesis of calculi. It is clear that enlarged prostate may be an innocent bystander in many elderly patients having bladder calculi. There are varieties of options available for management of both these conditions. The present review is focused on understanding of pathogenesis of bladder calculi in elderly male. It also provides an overview of various treatment modalities described in literature for management of this condition. Approach in each case should be individualized based on the patient’s clinical criteria and his choice, availability of various endourological gadgets, surgical expertise and experience.  相似文献   
992.

Objective  

To determine whether outcomes for patients admitted with UGIH differ depending on weekend versus weekday admission, and whether any such differences are mediated by discrepancies in the use and timing of endoscopy.  相似文献   
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994.

Purpose  

We hypothesized that in patients with left ventricular dysfunction undergoing implant of a biventricular ICD, the local dominant frequency during early induced ventricular fibrillation would be higher at an epicardial left ventricular position compared to an endocardial right ventricular position.  相似文献   
995.
Patients with impacted esophageal foreign bodies usually present with gastrointestinal and rarely with respiratory symptoms. Impacted esophageal foreign bodies may be identified by radiologic studies. Ingested radiolucent foreign bodies may be more difficult to diagnose, especially if the patient presents with minimal symptoms. We report a rare case of a child who presented with stridor and obstructive sleep apnea. The cause of respiratory symptoms was thought to be due to enlarged tonsils and adenoids, and the patient was scheduled for tonsillectomy and adenoidectomy. On re-evaluation by the surgeon on the day of surgery, the procedure was changed to diagnostic microlaryngoscopy and bronchoscopy to rule out any other cause. The patient’s respiratory symptoms were resolved when an incidental discovery and retrieval of the radiolucent esophageal foreign body was made. The diagnosis of radiolucent esophageal foreign body can be difficult and can be easily missed without reasonable clinical suspicion.  相似文献   
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Measurement of individual organ tissue oxygen levels can provide information to help evaluate and optimize medical interventions in many areas including wound healing, resuscitation strategies, and cancer therapeutics. Echo planar 19F MRI has previously focused on tumor oxygen measurement at low oxygen levels (pO2) <30 mmHg. It uses the linear relationship between spin‐lattice relaxation rate (R1) of hexafluorobenzene (HFB) and pO2. The feasibility of this technique for a wider range of pO2values and individual organ tissue pO2 measurement was investigated in a rat model. Spin‐lattice relaxation times (T1= 1/R1) of hexafluorobenzene were measured using 19F saturation recovery echo planar imaging. Initial in vitro studies validated the linear relationship between R1 and pO2 from 0 to 760 mmHg oxygen partial pressure at 25, 37, and 41°C at 7 Tesla for hexafluorobenzene. In vivo experiments measured rat tissue oxygen (ptO2) levels of brain, kidney, liver, gut, muscle, and skin during inhalation of both 30 and 100% oxygen. All organ ptO2 values significantly increased with hyperoxia (P < 0.001). This study demonstrates that 19F MRI of hexafluorobenzene offers a feasible tool to measure regional ptO2 in vivo, and that hyperoxia significantly increases ptO2 of multiple organs in a rat model. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
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