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71.
Kim  D; Porter  DH; Siegel  JB; Simon  M 《Radiology》1989,172(3):721-723
Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.  相似文献   
72.
Comorbidity has been used extensively to explain the numerous co-occurring psychiatric syndromes accompanying chronic posttraumatic stress disorder (PTSD). A cascade model is proposed as an alternative to comorbidity for the pathogenesis and clinical course of the condition. This model allows for a dynamic, integrated conceptualization of disease progression in PTSD. Findings in the clinical, epidemiological, neurobiological, and psychosocial literature which might support this model are described. Conceptual and heuristic difficulties and/or potential objections to the model are also examined. Finally, diagnostic and treatment implications as well as potential research applications of the model are discussed.  相似文献   
73.
74.
High-resolution MR imaging with local coils   总被引:4,自引:0,他引:4  
Kneeland  JB; Hyde  JS 《Radiology》1989,171(1):1-7
We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone.  相似文献   
75.
Kirkpatrick  JB; Hayman  LA 《Radiology》1987,162(2):509-511
Patchy white-matter lesions occur in the magnetic resonance (MR) imaging brain studies of 20%-30% of neurologically healthy elderly subjects. To determine the frequency of histologically verifiable white-matter lesions at autopsy in such subjects the authors examined serial, microscopic, whole brain sections from 15 clinically healthy subjects aged 52-72 years. Small white-matter lesions were found in 12. In these 12, zones of atrophic perivascular demyelination were present in eight brains. These are not the familiar thrombotic, embolic, or ischemic vascular lesions that produce acute necrosis. This mild vascular insufficiency produces atrophy, which has been recognized in the pathology literature but whose clinical significance remains unknown. Other lesions seen were small vascular malformations in the centrum ovale in four brains, diverticula of the lateral ventricle extending into the white matter in three, and an isolated central white-matter infarction in one. All of these lesions are probably the basis of the patchy white-matter lesions seen on MR imaging studies in the neurologically healthy elderly population.  相似文献   
76.
Klebsiella pneumoniae strains isolated from different clinical and environmental sources were examined for resistance to antibiotics, pentachlorophenol, and heavy metals using intracellular ATP measurements. Resistance to kanamycin, neomycin, gentamicin, and tobramycin was noted for the hospital strain but not for the environmentally derived isolates. On the other hand, strains isolated from pulp and paper mill effluents and receiving waters exhibited a higher degree of pentachlorophenol and heavy metal resistance. Chromosomal restriction endonuclease analysis (REA) digests of three environmental strains produced patterns that were different and readily distinguishable. Plasmids were detectable in these same environmental isolates; two of the three carried a 70 × 106 Da plasmid that is thought to mediate both antibiotic and heavy metal resistance.  相似文献   
77.
The effects of intermittent negative pressure ventilation have been studied in 20 patients with chronic obstructive pulmonary disease during an exacerbation of their disease. Measurements of arterial blood gas tensions and maximal inspiratory pressure (MIP) were performed before and after six hours of negative pressure ventilation or standard treatment (control day) given in random order on two consecutive days. After negative pressure ventilation the mean (SD) value of MIP increased from 68.1 (21.5) to 74.8 (20) cm H2O;* arterial oxygen tension (PaCO2) fell from 60.6 (12.2) to 50.9 (8.9) mm Hg* but PaO2 changed little (from 48.4 (7.4) to 47.6 (8.2) mm Hg). There were no significant changes on the control day in arterial blood gas tensions (PaO2 47.8 (8.1) and 48.9 (9.4) and Paco2 59.8 (10.9) and 57.5 (8.06) mm Hg) or in MIP (69.4 (22.4) and 70.9 (22.9) cm H2O). Six patients tolerated negative pressure ventilation poorly and these patients showed less improvement after negative pressure ventilation. Our results suggest that intermittent negative pressure ventilation can increase alveolar ventilation in patients with an exacerbation of chronic obstructive lung disease, particularly in those who tolerate the procedure well. Most subjects showed a fall in PaCO2 and an increase in MIP. The fact that PaO2 was unchanged despite the fall in PaCO2 suggests that gas exchange may deteriorate with negative pressure ventilation in these patients.  相似文献   
78.
BACKGROUND: Photochemical treatment (PCT) with amotosalen HCl (S-59) was developed to inactivate pathogens and white blood cells in plasma (PCT-FFP) used for transfusion support. STUDY DESIGN AND METHODS: An open-label, multicenter trial was conducted in patients with congenital coagulation factor deficiencies (factors [F]I, FII, FV, FVII, FX, FXI, and FXIII and protein C) to measure the kinetics of specific coagulation factors, hemostatic efficacy, and safety of PCT-FFP. Posttransfusion prothrombin time (PT), partial thromboplastin time (PTT), and clinical hemostasis were evaluated before and after PCT-FFP transfusions. RESULTS: Thirty-four patients received 107 transfusions of PCT-FFP for kinetic studies or therapeutic indications (mean dose, 12.8 +/- 8.5 mL/kg). Incremental factor recoveries ranged from 0.9 to 2.4 IU per dL per IU per kg (FII, FV, FVII, FX, FXI, and protein C). Mean pretransfusion PT (20.7 +/- 22.2 sec) corrected after PCT-FFP (13.8 +/- 2.4 sec, p < 0.001). Mean pretransfusion PTT (51.2 +/- 29.3 sec) corrected after PCT-FFP (32.0 +/- 5.1 sec, p < 0.001). Thirteen patients required 77 transfusions for therapeutic indications. PCT-FFP provided effective hemostasis and was well tolerated. CONCLUSIONS: Replacement coagulation factors in PCT-FFP exhibited kinetics and therapeutic efficacy consistent with conventional FFP.  相似文献   
79.
蛋白质组学及其相关技术在运动人体科学中的应用   总被引:1,自引:0,他引:1  
目的:对蛋白组学及蛋白芯片技术发展现状进行综述,为该技术在运动医学中的应用提供参考资料。资料来源:应用计算机检索PubMed2003-01/2006-12期间相关蛋白组学及蛋白芯片技术方面的文章,检索词“exercise AND protein chip,protein microarray”,并限定文章语言种类为English。同时计算机检索万方数据库2003-01/2006-12期间相关蛋白组学及蛋白芯片技术方面的文章,检索词“蛋白质,运动锻炼,运动医学”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与蛋白质组学及蛋白质芯片技术的研究相关。排除标准:重复研究或Meta分析类文章。资料提炼:共收集到312篇相关文献,32篇文献符合纳入标准,排除的280篇文献为内容陈旧或重复。资料综合:蛋白组学研究已成为基因组学研究后生命科学发展的大方向之一。它研究的主要内容包括:蛋白质分离与鉴定、蛋白质功能的确定、蛋白质翻译后修饰及相互作用、各种疾病或疲劳标志物的筛选与疾病诊断、生物信息学及药物开发等方面。文章在对蛋白质组学的发展及其相关技术在运动人体科学中的应用现状进行综述的基础上,对运动人体科学未来的发展方向进行了展望。由于蛋白质组学的建立以及蛋白质芯片技术的逐步完善,对运动人体科学的研究及其发展将起到很好的促进作用。结论:未来将从分子水平上阐明运动与人体适应的分子生物学机制,研究热点将集中于从运动营养蛋白质组学、反兴奋剂的蛋白质芯片技术、运动员机能评定的蛋白质芯片研究等方面。  相似文献   
80.
目的:构建重组人粒细胞-巨噬细胞集落刺激因子乳酸链球菌表达载体,为进一步研究人粒细胞-巨噬细胞集落刺激因子在乳链菌的表达及其治疗价值奠定基础。方法:实验于2005-04/2006-03在南方医科大学南方医院消化病研究所完成。①载体pNCSF的构建:将质粒集落刺激因子及含有P59启动子、USP45蛋白信号肽的pNBC1000质粒分别加入BamH Ⅰ和Pst Ⅰ进行双酶切,并用Apa Ⅰ、Sac Ⅰ进行双酶切鉴定,重组质粒命名为pNCSF。②SDGFP的TA克隆及载体pNCSFGFP的构建:将经过优化适合在乳链菌表达的人粒细胞-巨噬细胞集落刺激因子基因克隆于含有P59启动子、USP45蛋白信号肽的pNBC1000载体,得到重组质粒pNCSF;同时设计上下游引物经PCR扩增增强荧光表达蛋白(EGFP),TA克隆后经测序验证,再连接于pNCSF获得重组质粒pNCSFGFP。③载体pTRCSF、pTRCSFGFP的建立:将获得的pNCSF和pNCSFGFP进一步克隆于穿梭载体pTR1001c,以获得人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP。结果:①载体pNCSF构建结果:酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子)720bp的目的片段。②SDGFP的TA克隆及载体pNCSFEGFP的构建结果:SDGFP阳性克隆产物经EcoRⅠ酶切鉴定得到775bp目的片段。pNCSFEGFP酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子、SDGFP)1495bp的目的片段。③穿梭质粒pTRCSF、pTRCSFGFP酶切鉴定结果:经Xba Ⅰ、Sac Ⅰ进行双酶切鉴定,分别得到约717bp、1492bp大小目的片段。结论:获得了人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP,并经酶切鉴定和测序证实。  相似文献   
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