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31.
Prior to the introduction of cardioplegia, beating heart continuous coronary perfusion (BHCCP) was the only available method of myocardial protection. Currently, cardiac surgery on cardiopulmonary bypass with cardioplegic arrest is the gold standard strategy. Cardioplegic arrest provides an easier and safer way to operate on a still heart. It enables the performance of a broader range of cardiac procedures, and avoids the potential difficulties of continuous perfusion on a beating heart. Despite the overall effectiveness and safety of cardioplegia, some adverse effects remain, mainly due to the insult of ischemia, which results in ischemic reperfusion injury. As a result BHCCP has seen a revival as an alternative to cardioplegia for performing complex valvular surgery. Increasing experience reporting safety and efficacy of BHCCP is being published. However, despite the reported advantages, current available evidence validating safety and efficacy of BHCCP is controversial. This article provides an overview of BHCCP highlighting the current best available evidence supporting this strategy, concerns, controversies and potential areas for further research.  相似文献   
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BACKGROUND: A high percentage of hypertensive patients present an arm circumference of over 32 cm; the use of a large cuff is therefore recommended. Validation studies are usually performed in the general population using a standard-size cuff. The aim of this study was to assess the accuracy of the Omron M7 device in a population with an arm circumference ranging from 32 to 42 cm. DESIGN: A validation study was performed according to the International Protocol of the European Society of Hypertension. This protocol is divided into two phases: the first phase is performed on 15 selected participants (45 pairs of blood-pressure measurements); if the device passes this phase, 18 supplementary participants are included (54 pairs of blood-pressure measurements), making a total number of 33 participants (99 pairs of blood-pressure measurements), on whom the analysis is performed. METHODS: For each participant, four blood-pressure measurements were performed simultaneously by two trained observers, using mercury sphygmomanometers fitted with a Y tube; the measurements alternated with three by the test device. The difference between the blood-pressure value given by the device and that obtained by the two observers (mean of the two observations) was calculated for each measure. The 99 pairs of blood-pressure differences were classified into three categories (相似文献   
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Resin bonded bridges have become established as a treatment option for replacing missing teeth. Their development can be traced to the work of Rochette who used a macro mechanically bonded metal framework to stabilize mobile teeth. Adaptations of Rochette's concept, using natural teeth as pontics, have been presented. The use of a natural tooth has aesthetic and psychological advantages for the patient. The high failure rate of natural tooth pontics may be explained by a lack of support for the tooth on the metal framework. A clinical report is presented to illustrate a previously unreported technique to improve pontic support.  相似文献   
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The aim of this survey was to evaluate correlates for the patient's desire for surgical improvement of the cosmetic outcome after the primary operation for breast cancer. A cross-sectional study was carried out in a single follow-up outpatient clinic using a questionnaire. Patients were asked to assess their degree of satisfaction with the cosmetic results of their primary surgery and to state if they would like to undergo a further breast surgery to improve the appearance. Patients’ characteristics were correlated with this desire. After breast-conserving surgery, 21.6% of the patients stated that they desired surgical improvement, in comparison with 29.8% of the patients who underwent mastectomy. In the latter group, the desire for improvement remained constant up to 5 years after the initial operation, whereas it declined in the group of patients after breast-conserving surgery. Furthermore, a younger age and the perception that the appearance negatively influences femininity, partnership or sexual life were associated with a desire for further surgery. Breast reconstruction after mastectomy can be discussed with the patients even after a long follow-up, especially when the appearance seems to influence partnership issues.  相似文献   
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PURPOSE: Patients with cancer of unknown primary (CUP) account for about 10% of patients with metastatic spinal cord compression (MSCC). This study aims to define the appropriate radiation regimen for these patients. METHODS AND MATERIALS: Data of 143 CUP patients irradiated for MSCC were retrospectively evaluated. Short-course radiotherapy (RT) (1x8 Gy, 5x4 Gy, n = 68) and long-course RT (10x3 Gy, 15x2.5 Gy, 20x2 Gy, n = 75) plus 8 further potential prognostic factors (age, gender, performance status, visceral metastases, other bone metastases, number of involved vertebrae, ambulatory status, time of developing motor deficits before RT) were compared for functional outcome and survival. RESULTS: Improvement of motor function occurred in 10% of patients, no further progression of motor deficits in 57%, and deterioration in 33%. On multivariate analysis, functional outcome was positively associated with slower development of motor deficits (p < 0.001), absence of visceral metastases (p = 0.008) and other bone metastases (p = 0.027), and ambulatory status (p = 0.054), not with the radiation regimen (p = 0.74). Recurrence of MSCC in the irradiated region occurred in 7 patients after median 6 months. Median survival was 4 months. On multivariate analysis, better survival was significantly associated with absence of visceral metastases (p < 0.001), absence of other bone metastases (p = 0.005), ambulatory status (p = 0.001), and slower development of motor deficits (p = 0.030). CONCLUSIONS: For MSCC treatment in patients with CUP, no significant difference was observed between short-course and long-course RT regarding functional outcome and survival. Short-course RT appears preferable, at least for patients with a poor predicted survival, as it is more patient convenient and more cost-effective.  相似文献   
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Meriones shawi (M. shawi) is a particular semi-desert rodent known by its resistance to long periods of thirst. The aim of the present investigation is to clarify the underlying mechanisms allowing M. shawi to resist to hard conditions of dehydration. For this reason we used two different approaches: i) a morphometric study, which consists in measuring the effect of dehydration on body and kidneys weights as well as the report kidney weight/body weight, ii) By immunohistochemistry, we proceed to study the effect of dehydration on the immunoreactivity of central vasopressin (AVP) and the kidney aquaporin-2 (AQP-2) which is a channel protein that allows water to permeate across cell membranes. Our results showed both a body mass decrease accompanied by a remarkable kidneys hypertrophy. The immunohistochemical study showed a significant increase of AQP-2 immunoreactivity in the medullar part of Meriones kidneys allowing probably to Meriones a great ability to water retention. Consistently, we demonstrate that the increased AQP-2 expression occurred together with an increase in vasopressin (AVP) expression in both hypothalamic supraoptic (SON) and paraventricular nucleus (PVN), which are a major hub in the osmotic control circuitry.These various changes seen either in body weight and kidneys or at the cellular level might be the basis of peripheral control of body water homeostasis, providing to M. shawia strong resistance against chronic dehydration.  相似文献   
39.
Venous thromboembolism includes 2 inter-related conditions: Deep venous thrombosis and pulmonary embolism. Heparin and low-molecular-weight heparin followed by oral anticoagulation with vitamin K agonists is the first line and current accepted standard therapy with good efficacy. However, this therapeutic strategy has many limitations including the significant risk of bleeding and drug, food and disease interactions that require frequent monitoring. Dabigatran, rivaroxaban, apixaban, and edoxaban are the novel oral anticoagulants that are available for use in stroke prevention in atrial fibrillation and for the treatment and prevention of venous thromboembolism (HYPERLINK\l ”1). Recent prospective randomized trials comparing the NOACs with warfarin have shown similar efficacy between the treatment strategies but fewer bleeding episodes with the NOACs. This paper presents an evidence-based review describing the efficacy and safety of the new anticoagulants compared to warfarin.  相似文献   
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