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91.
BackgroundFewer pauses and better chest compression quality are thought to improve overall survival following cardiac arrest. This study aimed to measure the outcomes of adult nontraumatic out-of-hospital cardiac arrests (OHCAs) treated with 5:1 compressions-to-ventilations (Thumper 1007) or continuous chest compressions with ventilation (Thumper 1008 CCV) mechanical cardiopulmonary resuscitation (CPR) within a specified period of time.MethodsA retrospective observational cohort study of 515 adults with OHCA was conducted at the emergency department of an urban tertiary hospital. There were 307 patients in the Thumper 1007 phase (January 2008 to December 2009) and 208 patients in the Thumper 1008 CCV phase (January 2010 to May 2011). Return of spontaneous circulation (ROSC) and survival to hospital discharge were the primary outcome measures.ResultsPatients in the Thumper 1007 and Thumper 1008 CCV phases had comparable results with the following exceptions: less hypertension (42.4% vs. 62.0%), cerebrovascular accidents (11.4% vs. 25.0%), and faster emergency medical service response time intervals (mean, 3.7 vs. 4.5 minutes) with the Thumper 1007. The average ambulance transport time was 6.1 minutes in both phases. The rates of ROSC [35.1% vs. 23.5%; adjusted odds ratio (OR), 1.616; 95% confidence interval (CI), 1.073–2.432] and survival to hospital discharge (10.1% vs. 4.2%; adjusted OR 2.431; 95% CI, 1.154–5.120) were significantly higher with the Thumper 1008 CCV than with the Thumper 1007. Favorable neurologic outcome upon discharge, defined as cerebral performance category scores of 1 (good performance) or 2 (moderate disability), was not significantly different between the two phases [1.6% (5/307) vs. 1.9% (4/208); p = 0.802]. The Thumper 1008 CCV provided significantly faster average chest compression rates and shorter no-chest compression intervals than the Thumper 1007 after activation.ConclusionIn an emergency department with short ambulance transport times, continuous chest compressions with ventilation through mechanical CPR showed improved outcomes, including ROSC and survival to hospital discharge, in an adult with OHCA. However, there are a variety of confounding influences that may affect the validity of conclusions that have been drawn.  相似文献   
92.
Neonicotinoids are a new class of insecticides widely applied for crop protection. These insecticides act as agonists at nicotinic acetylcholine receptors, which cause insect paralysis and death. The high specificity for receptors in insects was considered to possess highly selective toxicity to insects and relative sparing of mammals. However, an increasing number of cases of acute neonicotinoid poisoning have been reported in recent years. We reported a man who developed respiratory failure and shock after ingestion of neonicotinoid insecticide. A detailed literature review found that respiratory, cardiovascular and certain neurological presentations are warning signs of severe neonicotinoid intoxication. The amounts of ingested neonicotinoid insecticide and the plasma neonicotinoid concentration are not useful guides for the management of intoxicated patients. Supportive treatment and decontamination are the practical methods for the management of all neonicotinoid‐poisoned patients.  相似文献   
93.
OBJECTIVES: since cuff dimensions are variable, we studied the influence of cuff geometry on flow mechanics, in an attempt to identify the optimum configuration. MATERIALS AND METHODS: bench studies involved the manufacture of anatomically accurate models of varying cuff dimensions, perfused in a specifically designed flow rig, simulating physiological conditions. Flow visualisation studies incorporating laser illumination of tracer particles enabled accurate analysis of flow patterns. RESULTS: the vortex created within the proximal cuff of each model during the deceleration phase of the cardiac cycle was strongly influenced by the aspect ratio (AR=cuff height:length). The standard and high cuffs (AR=1.63 and 1.18, respectively) demonstrated cohesive vortices and stable flow patterns. Low and long cuffs (AR=2.6 and 2.25, respectively) created more complex vortices with large areas of flow separation and low velocities. CONCLUSIONS: aspect ratio has an important influence on flow within the distal anastomosis, with cuff dimensions of 13 mm long and 8-11 mm high (standard and high cuffs) creating beneficial flow patterns anticipated to optimise wall shear stress and inhibit myointimal hyperplasia.  相似文献   
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95.
In Singapore, male osteoporosis is gaining greater importance due to our ageing population. Family physicians should screen for osteoporosis in elderly men and men with risk factors or secondary causes for the condition. A bone mineral density (BMD) test is used for diagnosis. FRAX® can be used to predict the absolute ten-year fracture risk. Management includes reduction of risk factors or secondary causes, fall prevention, appropriate physical activity and a diet adequate in calcium and vitamin D. Referrals to specialists for evaluation and therapy can be considered, particularly for younger men with more severe disease. Current first-line drug treatment includes bisphosphonates and teriparatide. Testosterone increases BMD of the spine, but data on fracture risk reduction is unavailable. Public and physician education with the involvement of health authorities can create greater awareness of this silent condition, which can lead to complications, morbidity and death, if left untreated.  相似文献   
96.
97.
Congenital melanocytic nevi (CMN) are benign proliferations that may be associated with various consequences depending on their size. They are characterized by a specific molecular signature, namely a postzygotic somatic NRAS or BRAF mutation. We have recently reported that large CMN (lCMN), which are classically associated with an increased melanoma risk, harbour cell subpopulations with specific clonogenic and tumorigenic potential. We wished to ascertain whether cells displaying similar properties persisted postnatally in medium CMN (mCMN). Eighteen medium M1, nine large and one giant NRAS‐mutated CMN were prospectively included in the study. Subpopulations of mCMN cells expressed stem cell/progenitor lineage markers such as Sox10, nestin and Oct4, as was the case in lCMN. Nevertheless, conversely to lCMN, mCMN cells with clonogenic properties were rarer. In vitro, approximatively one in 1500 cells isolated from fresh mCMN formed colonies that could be passaged. In vivo, mCMN seemed to harbour cells with less proliferative potential than the larger lesions as lCMN biopsies displayed a threefold expansion compared to mCMN when xenografted in Rag2?/? mice. Thus, our data revealed variations in clonogenicity and tumorigenic properties in NRAS‐mutated CMN according to size.  相似文献   
98.
The design and development of a simulator for endovascular repair of abdominal aortic aneurysm (AAA) is described. The simulator consists of an interchangeable model of a human AAA based on computed tomography data and is produced by means of computer-aided design and manufacture (CAD/CAM) techniques. The model has renal, iliac, and femoral arteries, and is perfused with a temperature controlled blood–analog fluid under simulated physiological flow conditions. Fluoroscopic imaging is simulated by a computerized imaging system that uses visible light. A movable video camera relays images in the antero–posterior and lateral planes of the AAA to a monitor. The imaging system allows arteriography and road-mapping to be performed so as to facilitate accurate deployment of endovascular stent-grafts. The system has been used for teaching and demonstrating endovascular techniques to clinicians, as well as the evaluation of new stent-graft devices. Its successful incorporation into endovascular workshops has demonstrated its role in the training of clinicians in endovascular repair of AAA. © 1998 Biomedical Engineering Society. PAC98: 0150-i, 8745Hw, 8759Fm  相似文献   
99.
Pneumothorax is the presence of air in the pleural cavity. It can be classified into spontaneous, traumatic or iatrogenic. The majority of pneumothorax cases are spontaneous, which can be further classified into primary spontaneous pneumothorax (PSP) or secondary spontaneous pneumothorax (SSP), defined by the absence or presence of obvious underlying lung disease respectively. The treatment of spontaneous pneumothorax includes simple aspiration, intercostal tube drainage or surgical intervention. When intercostal tube drainage is used, it is usually attached to an underwater-seal system. Mobile chest drains, such as the Heimlich valve, replace the underwater-seal and allow outpatient management of spontaneous pneumothoraces. The Heimlich valve however, is costly and not readily available in many local hospitals. Cheaper and easily obtainable alternatives which are also safe are being sought. This is a case report describing the use of the urine bag in the management of a patient with spontaneous pneumothrax.  相似文献   
100.
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