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BACKGROUND: Retrieval of optional vena cava filters (VCF) has been demonstrated to be safe and feasible in injured patients in 4 recent studies. However, 2 pulmonary emboli PE were reported in these studies with mean implant durations less than 19 days. In light of these occurrences, we changed our practice for VCF retrieval when patients had recovered from their injuries and at least 30 days after their discharge, or had been stable on therapeutic anticoagulation for deep venous thrombosis (DVT) or PE for at least 2 weeks. The aim of the current study was to assess the safety of this approach. METHODS: A review of prospectively collected data on optional VCF over a 16-month period. The filters were inserted prophylactically per an institutional practice guideline or for the presence of DVT or PE with a contraindication and/or complication to anticoagulation. All patients underwent duplex imaging of the lower extremities and had pre- and post- retrieval cavagrams. Demographics, duration of implantation, and complications were recorded. RESULTS: Eighty-three patients had optional VCF inserted since the change in our clinical practice. Indications included prophylaxis for high-risk trauma patients (n = 58), DVT or PE with acute contraindication to therapeutic anticoagulation (n = 22), or complications of anticoagulation (n = 3). Two patients developed lower extremity DVT after filter insertion and 1 patient developed a vena cava thrombosis. Retrieval was successful in 47 of 54 cases (87%) attempted. Median implantation duration was 142 days (range 17-475). A filter strut fracture occurred during retrieval without further consequences. No post-insertion or post-retrieval PE occurred in this study. CONCLUSION: Extended intervals for retrieval of VCF are safe and may maximize protection against pulmonary embolism.  相似文献   
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Yang L, Jacobsen KH. A systematic review of the association between breastfeeding and breast cancer. J Womens Health 2008;17:1635–45.  相似文献   
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Since the 1960s, childbirth education advocates have attempted to persuade pregnant women that educational preparation for labor and birth is an essential component of the transition to motherhood. Initially, pregnant women who were seeking unmedicated births as a refuge from the inhumane childbirth treatments of the mid‐20th century embraced this view. However, with the changing childbirth climate, including a growing preference for medicated birth, scheduled inductions, and cesarean sections, attendance has diminished and childbirth education finds itself at a crossroads. Commonly used childbirth education models/organizations and several new emerging models along with the available research literature and recommendations for clinical practice and research are presented.  相似文献   
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ObjectiveTo investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.MethodsThe calcium contents of the body parts of the animals were determined using atomic absorption spectrometer. Their phosphorus contents were determined colorimetrically using the molybdenum blue method.ResultsThe calcium and phosphorus contents were significantly higher in the bone samples than in the other animal parts investigated (P<0.05). The calcium contents of all the edible parts were higher in chicken than in the other animals. High calcium and phosphorus contents were detected in the faeces of chicken and goat, and that of cattle and goat, respectively. Low calcium and phosphorus contents were detected in the urine samples. Calcium: phosphorus ratios calculated for the bones of chicken, cattle and goat were satisfactory.ConclusionsIn conclusion, calcium and phosphorus contents of the animal parts vary significantly and their relative contents may be related to the animal's diet. Chicken parts may be the preferred dietary source of these minerals. This study highlights the need for routine investigation of the mineral contents of food, which is necessary for proper nutritional guidelines.  相似文献   
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