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81.
目的探讨眶骨延长术扩大眶容积治疗眼球突出的可行性。方法1年龄山羊6只,环行截开右侧眶壁,于眶上壁放置延长器,侧向延长1.5cm,经大体、X线、干骨标本及组织学观察成骨情况。结果6只山羊眶骨得到不同程度的侧向延长,延长侧随着眶骨容量的增加,眼球突度较自身对照侧为小。结论眶骨延长术可造成山羊眶骨侧向移位,有可能成为治疗眼球过度突出的方法之一。 相似文献
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83.
Bing Feng P. Hendrik Pretorius Troy H. Farncombe Seth T. Dahlberg Manoj V. Narayanan Miles N. Wernick Anna M. Celler Jeffrey A. Leppo Michael A. King 《Journal of nuclear cardiology》2006,13(3):354-361
BACKGROUND: Dynamic single photon emission computed tomography (SPECT) acquisition and reconstruction of early poststress technetium 99m teboroxime washout images has been shown to be useful in the detection of coronary disease. Assessment of poststress regional wall motion may offer additional use in assessing coronary disease. Our goal was to investigate the feasibility of simultaneously imaging myocardial ischemia and transient poststress akinesis using gated-dynamic SPECT. METHODS AND RESULTS: A gated-dynamic mathematical cardiac torso (MCAT) phantom was developed to model both teboroxime kinetics and cardiac regional wall motion. A lesion was simulated as having delayed poststress teboroxime washout together with a transient poststress wall motion abnormality. Gated projection data were created to represent a 3-headed SPECT system undergoing a total rotation of 480 degrees . The dynamic expectation-maximization reconstruction algorithm with postsmoothing across gating intervals by Wiener filtering, and the ordered-subset expectation maximization reconstruction algorithm with 3-point smoothing across gating intervals were compared. Compared with the ordered-subset expectation maximization with 3-point smoothing, the dynamic expectation-maximization algorithm with Wiener filtering was able to produce visually higher-quality images and more accurate left ventricular ejection fraction estimates. CONCLUSION: From simulations, we conclude that changing cardiac function and tracer localization possibly can be assessed by using a gated-dynamic acquisition protocol combined with a 5-dimensional reconstruction strategy. 相似文献
84.
目的探讨软组织血管瘤多排CT血管成像的影像表现方法回顾性分析临床、手术及病理证实20例软组织血管瘤CT平扫、增强和CT血管成像的不同表现结果CT平扫病灶呈软组织密度,5例灶内或灶缘见斑点状或斑块状高密度钙化灶;20例增强后病灶血管成像呈不同表现,12例动脉期瘤体内呈网状血管强化并见明显的瘤体供血动脉,其中单支供血动脉4例,2支以上多支供血动脉8例,供血动脉较对侧明显增粗瘤体内明显迂曲静脉血管6例,而静脉期瘤体表现为网状血管阴影强化8例病变动脉期瘤体不强化或仅轻微强化,且无明显供血动脉参与供血,静脉期瘤体逐渐均匀一致强化结论软组织血管瘤的多排螺旋CT血管成像可清晰显示软组织血管瘤的形态、大小、供血血管 相似文献
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86.
Brendan McCormack BSc DPSN PGCEA RGN RMN Clinical Lecturer in Nursing 《Journal of advanced nursing》1992,17(2):187-197
The research describes how nursing staff on a general surgical ward in a district general hospital perceived the delivery method of nursing care in practice. The study design was based on ethnographic methods and data were collected by diary keeping and semi-structured interviews. An organizational method based on the principles of primary nursing had been implemented on the ward for 2 years prior to the study commencing. As well as talking in general terms about primary nursing, the nursing staff talked at some length about specific issues related to their practice. 相似文献
87.
T Y Nakagawa H Von Grafenstein J E Sears J Williams C A Janeway R A Flavell 《European journal of immunology》1991,21(11):2851-2855
CD4+ T cells recognize processed exogenous antigen in the form of peptides bound to syngeneic major histocompatibility complex class II molecules on antigen-presenting cells. We have developed a novel and convenient method to synthesize and map CD4+ T cell epitopes of cloned antigens using polymerase chain reaction (PCR)-directed construction of genes expressing recombinant protein fragments. Unique restriction sites incorporated into the PCR primers were employed for the unidirectional cloning of gene fragments into a bacterial expression vector that can be induced to high-level expression. The bacterial lysate could be used directly in T cell proliferation assays. Overlapping recombinant fragments spanning the entire protein were generated and tested. The length of the sequence containing the epitope was further reduced by utilizing PCR to generate 3' truncations. Finally, a small number of overlapping peptides spanning a sequence of 39 amino acids were synthesized to identify a thirteen-amino acid peptide epitope within chicken transferrin that stimulates the T helper cell clone D10.G4.1. PCR-directed construction of fragments of antigen allows for optimal design of strategies for the mapping and analysis of CD4+ T cell epitopes. 相似文献
88.
清咽雾化液为紫红色澄明灭菌溶液,经95例急慢性咽喉炎临床治疗观察,其临床痊愈率与显效率为81.04%,与对照组比较有显著差异。药效研究具有抗炎消肿、镇咳祛痰、改善微循环、增强免疫功能等作用。其可以提高患者唾液中IgG水平,且具有统计学差异。 相似文献
89.
What should nurse teachers be doing? A preliminary study 总被引:1,自引:0,他引:1
Heather A. Cahill BSc RGN RMN RCNT RNT Cert Ed 《Journal of advanced nursing》1997,26(1):146-153
There is little doubt that the role of the nurse teacher is complex and multifaceted in nature. The apparently conflicting demands of NHS trusts and education in the United Kingdom, at the time of integration of nurse education into the higher education sector, further complicates the role. This recognition underlines the need to capture and measure key aspects of nurse teacher function in order to maximize educational gain. Using a comprehensive literature review, focus group discussions and a small number of individual semi-structured interviews, this preliminary study explored the issue of teacher workload, from the perspective of the principal stakeholders in nurse and higher education. Competing research and clinical practice objectives for nurse teachers are identified against a background of changing health care provision, reduced availability of placements and an increased need for evidence-based practice. 相似文献
90.
Karen A Luker PhD BNurs RGN RHV NDNCert Kinta Beaver BA RGN DPSN Samuel J Leinster BSc MD FRCS R Glynn Owens BTech DipPsych DPhil AFBPsS Lesley F Degner PhD RN Jeffrey A Sloan PhD BSc 《Journal of advanced nursing》1995,22(1):134-141
Nurses can play a key role in patient education, including providing patients with useful and approrate information Rather than focusing on the process of education or information giving by nurses, this study places emphasis on the content of that information by taking the patients'perspective and asking the patients themselves what particular types of information are perceived as important at a specific point in time The aim of the study was to explore what particular types of information were important to women newly diagnosed with breast cancer, to enable nurses and other health care professionals to utilize their time as effectively as possible and provide a high-quality service to individuals in their care Women with breast cancer (a mean of 2 5 weeks from diagnosis) were interviewed and asked to compare items of information The items of information were presented m pairs and the women stated a preference for one item in that pan- Thirty-six pairs were presented in total The analysis involved the use of a Thurstone scaling model, which allowed rank ordermgs, or profiles of information needs, to be developed, reflecting the perceived importance of each item Information about the likelihood of cure, the spread of the disease and treatment options were perceived as the most important items of information at the tune of diagnosis Other information needs, in order of descending priority, included information about the risk to family, side-effects 相似文献