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71.
目的 观察中面部牵引成骨技术对眼眶周围软、硬组织结构的三维空间位置变化的影响.方法 回顾性分析2003年9月至2006年6月接受Le Fort III型截骨+中面部牵引成骨术的8例Crouzon综合征患者CT数据,平均年龄11.9岁,实施影像三维重建后,采用眶耳平面(术前)作为测量的基准平面,分别选择眶上点、眶下点、眶内缘点、眶外缘点、眼球前点、眼球后点,以及上、下、内、外四直肌与眼球的附着点作为评估标志,以双侧耳门上点连线作为颅底宽度基准,记录各个主要标志点至耳门上点连线的矢状距(y轴向)、垂直距(z轴向)以及眼球前点、眼球后点的水平间距(x轴向)变化,行配对t检验,并与健康对照组比较.结果 牵引成骨术前后眼球前点的y轴向及z轴向位置并没有显著性变化,但x轴向间距变化为-3.40 mm;眶下点移动在y轴向平均12.24 mm,z轴向平均4.25 mm;眶内缘点移动在y轴向平均10.11 mm,z轴向平均2.80 mm;眶外缘点移动在y轴向平均9.86 mm,z轴向平均2.31mm;下直肌支点移动,y轴向平均3.63mm,z轴向平均2.98mm.其余各标记点未见有临床意义的位移变化.结论 以Le Fort III型截骨为主的面中部牵引成骨技术,可以使Crouzon综合征患者的术后眼眶内、外、下侧壁均出现明显的前、下方移位,而患者的眼球没有显著性的矢状向位置变化,仅呈现轻度的内移、下降和前上方旋转. 相似文献
72.
目的探讨MR流量测量与不同感兴趣区(ROI)直径的关系。方法使用Philips 1.5T双梯磁共振机流量测定程序,测量2mm内径塑胶管中不同流量的水(0.5、1.0、1.5、2.0、2.5ml/s),不同流向(流入及流出方向)、不同ROI位置(测量图中心区和偏中心区)与不同的ROI直径(直径0.5、1.0、1.5、2.0mm)流量变化关系,统计计算标准的ROI直径。结果在不同流量、流向和测量位置中,流量与ROI直径大小存在明显的直线相关(r>0.95,P<0.05),ROI直径大小显著地影响测量结果,当ROI直径取值等于测量图直径的0.6040±0.0480时,所测结果与实际流量一致。在不同流量下的不同流向及ROI位置对流量测定无影响(P>0.05)。结论对直径2mm流量测定,应选取测量图上直径的0.6040±0.0480 ROI进行。 相似文献
73.
中鼻道及其周围结构的解剖学观测 总被引:1,自引:0,他引:1
目的 探讨临床上经上颌窦口进入上颌窦诊疗的途径。方法 在 40例成人尸体颅矢状切面上 ,对中鼻道、半月裂孔、上颌窦口及其周围结构进行解剖学观测及上颌窦口的探针插入试验。结果 中鼻道、半月裂孔的长度分别为5 6.3 6± 2 .5 8mm、2 1.46± 1.79mm ;40例中 ,2 8侧 (70 .0 0 % )的上颌窦口位于半月裂孔的中 1/3部 ;12侧 (3 0 .0 0 % )的上颌窦口位于半月裂孔的后 1/3部。上颌窦口的形态不一。上颌窦口的前后径为 3 .14± 0 .47mm。上颌窦口距鼻腔底部、鼻小柱的距离分别为 3 0 .41± 2 .85mm、49.5 2± 2 .3 7mm。鼻小柱到上颌窦口与到鼻腔基底面连线的夹角为 40 .2± 3 .7°。 3 7侧 (92 .5 0 % )的上颌窦口能用直径≤ 2 .5mm的探针穿过。结论 经上颌窦自然开口行上颌窦口穿刺是安全、简便和有效的一种诊治方法。 相似文献
74.
JOHN CHALMERS 《British journal of clinical pharmacology》1996,42(1):29-35
1 A 'retrospective' of the development of the drug treatment of hypertension is presented from the early days of ganglion blockers to the present time together with a review of the evidence of benefit from treatment.
2 Current issues and debates are summarised including shortfalls in the control of hypertension in populations, difficulties surrounding the measurement of blood pressure, disagreement on the levels of blood pressure to treat, the goal blood pressures to aim at, issues surrounding lifestyle measures such as the low salt diet and low intensity exercise, and treatment with diuretics and with calcium antagonists.
3 A 'perspective' is presented on some avenues for progress in the years ahead. These will include the identification of genetic markers to determine the hypertensive individuals with the greatest risk of death and of cardiovascular complications. 相似文献
2 Current issues and debates are summarised including shortfalls in the control of hypertension in populations, difficulties surrounding the measurement of blood pressure, disagreement on the levels of blood pressure to treat, the goal blood pressures to aim at, issues surrounding lifestyle measures such as the low salt diet and low intensity exercise, and treatment with diuretics and with calcium antagonists.
3 A 'perspective' is presented on some avenues for progress in the years ahead. These will include the identification of genetic markers to determine the hypertensive individuals with the greatest risk of death and of cardiovascular complications. 相似文献
75.
J. YERGAN† T.J. PHILLIPS‡ D. C. SCHAAD§ A. MAY¶ R. DRICKEY‡ M. S. YERBY§ 《Medical education》1988,22(4):317-324
The University of Washington School of Medicine (UWSM) has initiated new efforts to build a regional minority applicant pool and to expand its educational programmes to accommodate students from disadvantaged backgrounds. Specific interventions include: establishment of medical career planner position to coordinate region-wide outreach; pre-entry education; and support activities once enrolled. This study describes specific services and presents sociodemographic and performance data on 56 minority and 280 majority students entering the UWSM between 1981 and 1985. Economic status and educational background of minority students were significantly below that of majority students, several flexible academic policies enabled most students to achieve mastery in courses and to progress through the curriculum. The educational data base utilized in this study, and those at other institutions, can assume important roles in the identification of problem areas in the education of disadvantaged students and in evaluation of the interventions attempted. 相似文献
76.
作者测量了新疆地区768例3~7岁维吾尔族、汉族儿童心脏径线。心脏横径6岁组维吾尔族大于汉族。不分年龄组左心横径、心横径、心深径维吾尔族大于汉族,左侧位心膈交点至前胸膜面的距离维吾尔族女童大于汉族女童。两民族心横径与心脏体积的相关系数分别大于心脏深径与心脏体积的相关系数。本文提供了新疆地区3~7岁维吾尔族、汉族儿童各年龄组和不分年龄组心脏径线的正常数据。 相似文献
77.
L Kovacs A Zimmermann G Brockmann M Gühring H Baurecht N A Papadopulos K Schwenzer-Zimmerer R Sader E Biemer H F Zeilhofer 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(11):1193-1202
Three-dimensional recording of the surface of the human body or of certain anatomical areas has gained an ever increasing importance in recent years. When recording living surfaces, such as the human face, not only has a varying degree of surface complexity to be accounted for, but also a variety of other factors, such as motion artefacts. It is of importance to establish standards for the recording procedure, which will optimise results and allow for better comparison and validation. In the study presented here, the faces of five male test persons were scanned in different experimental settings using non-contact 3D digitisers, type Minolta Vivid 910). Among others, the influence of the number of scanners used, the angle of recording, the head position of the test person, the impact of the examiner and of examination time on accuracy and precision of the virtual face models generated from the scanner data with specialised software were investigated. Computed data derived from the virtual models were compared to corresponding reference measurements carried out manually between defined landmarks on the test persons' faces. We describe experimental conditions that were of benefit in optimising the quality of scanner recording and the reliability of three-dimensional surface imaging. However, almost 50% of distances between landmarks derived from the virtual models deviated more than 2mm from the reference of manual measurements on the volunteers' faces. 相似文献
78.
Jacqueline Barnes 《Child and Adolescent Mental Health》1997,2(4):163-169
There is increasing interest in the influence of community characteristics on child development and family functioning. In order to address questions on community influence, it is important to be aware of the measures available and their strengths and limitations. Useful strategies have been developed within a number of disciplines, including sociology, social and community psychology, and criminology. Methods include summarising information from existing administrative databases and census data, conducting observations, and using survey instruments with residents. The most commonly used methods are reviewed and their psychometric properties described . 相似文献
79.
This paper describes the efforts of the Department of Family and Community Health at Sultan Qaboos University in providing opportunities for the development of 'hands-on' problem-solving skills appropriate for Oman. The curriculum of the Department is discussed, highlighting the unusual emphasis of this discipline in both the preclinical and clinical curriculum of the College of Medicine. The importance of continuous assessment and supervision of students is discussed. Course-work in the preclinical curriculum of the Department is kept to a minimum. Field-work forms an important part of preclinical training, where application and problem-based learning are emphasized. During the clinical years the students are exposed to an integrated series of lectures and practicals covering core knowledge in clinical medicine. Practical clinical training, over a total period of 15 weeks, takes place at a variety of sites where common problems in primary health care in Oman are handled by students under supervision. 相似文献
80.
Electrical impedance scanning in breast tumor imaging: correlation with the growth pattern of lesion
WANG Kan WANG Ting FU Feng JI Zhen-yu LIU Rui-gang LIAO Qi-mei DONG Xiu-zhen 《中华医学杂志(英文版)》2003,122(1):1501-1506
Background This study researched the electric impedance properties of breast tissue and demonstrated the differentcharacteristic of electrical impedance scanning (EIS) images.Methods The impedance character of 40 malignant tumors, 34 benign tumors and some normal breast tissue from 69patients undergoing breast surgery was examined by EIS in vivo measurement and mammography screening, with aseries of frequencies set between 100 Hz-100 kHz in the ex vivo spectroscopy measurement.Results Of the 39 patients with 40 malignant tumors, 24 showed bright spots, 11 showed dark areas in EIS and 5showed no specific image. Of the 30 patients with 34 benign tumors there were almost no specific abnormality shown inthe EIS results. Primary ex vivo spectroscopy experiments showed that the resistivity of various breast tissue take thefollowing pattern: adipose tissue>cancerous tissue>mammary gland and benign tumor tissue.Conclusions There are significant differences in the electrical impedance properties between cancerous tissue andhealthy tissue. The impedivity of benign tumor is lower, and is at the same level with that of the mammary glandulartissue. The distinct growth pattern of breast lesions determined the different electrical impedance characteristics in theEIS results. 相似文献