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91.
OBJECTIVE: On November 23, 1992, the first endovascular stent graft (ESG) repair of an aortic aneurysm was performed in North America. Following the treatment of this patient, we have continued to evaluate ESG over the past 10 years in the treatment of 817 patients. SUMMARY AND BACKGROUND DATA: Abdominal (AAA) or thoracic (TAA) aortic aneurysms are a significant health concern traditionally treated by open surgical repair. ESG therapy may offer protection from aneurysm rupture with a reduction in procedure morbidity and mortality. METHODS: Over a 10-year period, 817 patients were treated with ESGs for AAA (723) or TAA (94). Patients received 1 of 12 different stent graft devices. Technical and clinical success of ESGs was reviewed, and the incidence of procedure-related complications was analyzed. RESULTS: The mean age was 74.3 years (range, 25-95 years); 678 patients (83%) were men; 86% had 2 or more comorbid medical illnesses, 67% of which included coronary artery disease. Technical success, on an intent-to-treat basis was achieved in 93.8% of patients. Primary clinical success, which included freedom from aneurysm-related death, type I or III endoleak, graft infection or thrombosis, rupture, or conversion to open repair was 65 +/- 6% at 8 years. Of great importance, freedom from aneurysm rupture after ESG insertion was 98 +/- 1% at 9 years. There was a 2.3% incidence of perioperative mortality. One hundred seventy five patients died of causes not related to their aneurysm during a mean follow-up of 15.4 months. CONCLUSIONS: Stent graft therapy for aortic aneurysms is a valuable alternative to open aortic repair, especially in older sicker patients with large aneurysms. Continued device improvements coupled with an enhanced understanding of the important role of aortic pathology in determining therapeutic success will eventually permit ESGs to be a more durable treatment of aortic aneurysms.  相似文献   
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OBJECTIVE: The purpose of this study was to measure racial and ethnic differences in the proportion of Medicaid patients who receive epidural analgesia during labor and delivery. STUDY DESIGN: Using 1998 Georgia Medicaid claims data in a standard State Medicaid Research File format, we identified claims for epidural analgesia among all women who had a normal vaginal delivery during 1998. RESULTS: There were 29,833 women who met our inclusion criteria, of whom 15,936 (53.4%) had epidural analgesia. Epidural analgesia rates were lower for black women (49.5%), Hispanic women (35.3%), and Asian women (48.1%) than for white, non-Hispanic women (59.6%; P<.001). Rural women had lower epidural rates (39.2%) than urban women (62.1%). CONCLUSION: The study subjects all had identical Medicaid insurance and met the same low-income Medicaid eligibility criteria, yet race/ethnicity was still a significant predictor of epidural analgesia after we had controlled for age, rural-urban residence, and availability of anesthesiologists. Further studies are needed to assess perceived benefits, risks, costs, and obstacles to epidural analgesia that are perceived by patients, physicians, nurses, and midwives.  相似文献   
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INTRODUCTION: Crystallography is the key initial component for structure-based and fragment-based drug design and can often generate leads that can be developed into high potency drugs. Therefore, huge sums of money are committed based on the outcome of crystallography experiments and their interpretation. AREAS COVERED: This review discusses how to evaluate the correctness of an X-ray structure, focusing on the validation of small molecule-protein complexes. Various types of inaccuracies found within the PDB are identified and the ramifications of these errors are discussed. The reader will gain an understanding of the key parameters that need to be inspected before a structure can be used in drug discovery efforts, as well as an appreciation of the difficulties of correctly interpreting electron density for small molecules. The reader will also be introduced to methods for validating small molecules within the context of a macromolecular structure. EXPERT OPINION: One of the reasons that ligand identification and positioning, within a macromolecular crystal structure, is so difficult is that the quality of small molecules widely varies in the PDB. For this reason, the PDB can not always be considered a reliable repository of structural information pertaining to small molecules, and this makes the derivation of general principles that govern small molecule-protein interactions more difficult.  相似文献   
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This article describes the use of a Postural Mechatronic Assistant Trainer (PMAT) in pediatric Nissen surgery. This mechatronic system enables users to establish the logistical considerations for solo surgery and determine the advantages this new tool offers for the autonomous handling of optics.  相似文献   
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目的探讨检测细胞核仁形成区酸性非组蛋白在胆囊癌诊断与监测中的价值。方法应用细胞银染技术对体外激活的外周血和胆汁淋巴细胞染色 ,并对胆囊组织作核仁形成区嗜银蛋白银染 ,计算外周血和胆汁中硝酸银染色酸性非组蛋白 (Ag) NORs面积与核面积的比值 (IS % )和组织切片中AgNOR颗粒面积。结果正常人 (2 0例 )、慢性胆囊炎 (90例 )与胆囊癌之间 (2 1例 )外周血、胆汁T细胞Ag NORs面积与核面积的比值和组织切片中AgNOR面积差异均有显著性意义 ,血清、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )逐级降低 ,组织切片中AgNOR面积逐级升高 ,且血清、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )、组织中AgNOR面积三者相互间有良好的直线相关性 (P均 <0 0 1)。结论监测胆囊病变过程中患者外周血、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )和组织切片中AgNOR面积的变化 ,有助于胆囊癌的诊断  相似文献   
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Twenty-three yellow fever (YF) vaccine viruses and three wild-type YF viruses were propagated independently in human adenocarcinoma (SW13) cells and mosquito Aedes albopictus C6-36 cells. The three YF 17DD vaccine viruses were found to be slightly temperature sensitive (ts) at 39.5 degrees C versus 37.0 degrees C (efficiency of plaquing 0.04 to 0.1) following propagation in C6-36 but not in SW13 cells. A plaque-purified preparation of the 17DD vaccine manufactured in Brazil was ts when grown in C6-36 cells and remained ts when passaged back into the SW13 cell line.  相似文献   
100.
合欢皮中新皂甙的结构鉴定   总被引:7,自引:2,他引:5  
从合欢皮(Albizziae cortex)的95%乙醇提取物的正丁醇萃取部分中分离得到3个新的三萜皂甙,用化学方法及1H-和13C-NMR,DEPT,COSY,TOCSY,HMQC-COSY,HMQC-TOCSY,HMBC,NOESY等波谱方法鉴定其结构为:I(1个三萜,9个糖,2个单萜),命名为合欢皂甙(julibroside)J1;II(1个三萜,8个糖,2个单萜),命名为合欢皂甙J2;II(1个三萜,9个糖,2个单萜),命名为合欢皂甙J3。  相似文献   
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