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41.
Magnetization prepared segmented acquisition requires a view order that maximizes signal contrast during the acquisition of the central portion of k-space. Steady state free precession (SSFP) acquisition further requires a view order that minimizes changes in phase-encoding gradients from one repetition to the next in order to minimize eddy current artifacts. In this article, optimal view ordering schemes satisfying these two requirements are formulated and applied to inversion prepared 3D SSFP contrast-enhanced MR angiography (MRA). Experiments on phantoms and pigs demonstrated improved background suppression and reduced image artifacts.  相似文献   
42.
目的 对供者肝脏等器官的联合获取、修整和保存方法进行研究。方法 采用原位腹主动脉和门静脉插管、低温灌注,快速多器官联合获取、低温保存技术及体外修整获得可供移植的肝移植物。结果 获取122例供者的移植物,平均热缺血时间为4min30s,平均获取时间为20min,平均冷缺血时间为10h。均采用4℃的HCA液(高渗枸橼酸盐腺嘌呤溶液)和UW液灌注和保存。118例修整成适用于临床用的肝的移植物,76例供肝在移植前留取了病理活检标本,病理检查提示供肝结构正常。移植术后,无原发性肝无功能发生。结论 该方法适合于供者肝脏等器官的快速联合获取、修整和保存。  相似文献   
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44.
3—氯—4—氟苯胺的生产与研究概况   总被引:1,自引:0,他引:1  
评述了3-氯-4-氟苯胺的实验室研究和工业生产现状,特别对氯化、硝化、氟化和还原等反应中间体的制备及其质量作了分析。  相似文献   
45.
海藻硫酸多糖的制备及其性质研究   总被引:11,自引:0,他引:11  
目的 建立一套从褐藻中提取海藻硫酸多糖(SP)简单可行的工艺流程。方法 采用乙醇分级提取和Sevage去除蛋白的方法分离、纯化SP,并用Molish反应、Fehling反应、茚三酮法和硫酸基法等鉴定SP产品,用苯酚硫酸法测定SP产品中的糖含量,硫酸基法测定SP产品中的硫酸基含量。结果 从褐藻中得到了SP产品,其得率为3%,SP产品的总糖含量高达85.4%,硫酸基含量为5.3%。结论 我们建立的SP制备工艺流程简单可行,所得产品确系硫酸酯化的海藻多糖。  相似文献   
46.
Background Nowadays, liver resection is a routine operative procedure in surgical centers, and strategies must be aimed at avoiding additional risk factors. Extrahepatic isolation of portal vein, hepatic artery and hepatic duct, as well as lymphadenectomy of the liver hilum are generally accepted steps of liver resection, even for metastatic and benign indications. Our primary aim was to analyze the feasibility, blood loss, blood transfusion requirements, incidence of complications, and outcome using the approach for intrahepatic devascularization leaving the extrahepatic hilus untouched. Materials and methods Thirty-eight consecutive patients with resection for metastases and benign liver tumors were selected. After hilar examination, the extrahepatic structures remain intact, and during parenchyma dissection, the whole right or left or the appropriate bi-segmental pedicle is isolated intrahepatically and then transected using a stapler device. Results The used technique was feasible in all cases, and no intra- or postoperative surgical complications were observed. To date, no tumor recurrence was found in the hilum during the follow-up period. Conclusion The intrahepatic pedicle stapling technique appears to be feasible and safe in liver resection. Hilar dissection can, thus, be avoided in liver metastasis and benign liver tumors.  相似文献   
47.
口腔门诊治疗并发晕厥106例回顾分析   总被引:2,自引:0,他引:2  
目的:通过对1983年以来,孝感市中心医院口腔中心门诊治疗并发晕厥106例的回顾性分析,探讨口腔门诊治疗并发单纯性晕厥的原因及一些相关因素,增强医患双方的防治意识,安全顺利的进行口腔门诊治疗。方法:对106例单纯性晕厥反应,采取现场询问式调查的方法,对其一般情况,口腔门诊治疗经历,治疗时的心态,口腔门诊治疗的了解,以及不同口腔治疗晕厥发生情况等进行调查、归纳、分析。结果:1)晕厥的发生与患者的年龄有关,12~40岁口腔门诊治疗经历欠缺的患者是口腔门诊治疗并发晕厥的高危人群。2)口腔患者进行治疗前心理准备充足与否对并发晕厥反应的影响较大。3)晕厥在口腔门诊某些治疗中发生率较高,拔牙术最多,其次为脓肿切排。86%(92例)属因畏惧疼痛导致紧张而诱发的血管抑制性晕厥。4)晕厥多发生于治疗初期(93:13)。结论:口腔门诊治疗并发晕厥临床表现多不严重,但对患者就诊和医师的治疗影响明显,切实做好口腔治疗错误信息,消除和减轻他们的疑虑和畏惧的紧张心情,对保障口腔门诊治疗安全尤为重要。  相似文献   
48.
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: (1) frozen foods; (2) fresh produce and/or highly perishable foods requiring refrigeration; (3) fast foods and prepared foods; (4) shelf-stable foods; (5) specialized study and non-retail (point of production) foods; and (6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects.  相似文献   
49.
BACKGROUND: Gastrointestinal spasms and cramps are common in children as well as in adults. Alternative medical practices such as chiropractice and homeopathy are becoming increasingly popular in Europe and the USA. The effectiveness and tolerability of the homeopathic preparation Spascupreel was compared with that of hyoscine butylbromide treatment in children <12 years of age. METHODS: An observational cohort study in 204 children <12 years was conducted over a 1 week treatment period. The efficacy of the respective therapies were evaluated on the effect on severity of spasms and clinical symptoms (pain/cramps, sleep disturbances, distress, eating or drinking difficulties and frequent crying). Compliance was evaluated on a four-point scale from 'very good' to 'low'. Evaluation was done by the practitioner based on information given by the patient or minder. RESULTS: The analysis showed comparative improvements with the homeopathic preparation and hyoscine butylbromide therapy on severity of spasms, pain/cramps, sleep disturbances, eating or drinking difficulties, and frequent crying, all as evaluated by the practitioner. Both treatments were very well tolerated. CONCLUSIONS: For patients opting for a homeopathic therapy, Spascupreel seems to be an effective and well tolerated alternative to conventional therapies in children suffering from gastrointestinal spasms.  相似文献   
50.
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