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41.
42.
The onset of ablation of the evoked adductor pollicis muscle twitch in children: a clinical perspective 总被引:1,自引:0,他引:1
The time to loss of the adductor pollicis muscle response to ulnar nerve stimulation at 1 Hz (twitch) after succinylcholine, 1.5 mg.kg-1 intravenously (IV), or vecuronium, 0.1 mg.kg-1 (IV), administration was assessed visually in 134 children, age 2-13 yr, during clinically determined, deep halothane, enflurane and isoflurane anaesthesia. The overall time to twitch ablation and duration of succinylcholine's action is in agreement with published times obtained under controlled experimental conditions; the onset time following vecuronium is comparable to those observed during a similar anaesthetic background measured under controlled experimental conditions. Twitch ablation after succinylcholine was achieved in half the time needed following vecuronium regardless of anaesthetic agent. Succinylcholine's and vecuronium's onset time as well as succinylcholine's duration is adequately assessed by the outlined, simple clinical means. The choice of inhalation agent does not affect the time to visible twitch ablation in a clinically relevant manner; nor does it make an appreciable difference, in clinical terms, in succinylcholine's duration of action. 相似文献
43.
亚硝酸盐法测定超氧化物歧化酶活性 总被引:1,自引:0,他引:1
用亚硝酸盐、氰化钾抑制区别法测定样品中的 Cu,Zn-SOD 和 Mn-SOD,灵敏度高,重现性好,操作简便。实验表明,抑制率达50%时所需 SOD 的浓度为0.07 μg/ml,其批内和批间的变异系数分别为6.0%和5.5%,鸡肝 Cu,Zn-SOD 与 KCN 的抑制复合物的表观解离常数 K′为288.6±45.5 μmol。 相似文献
44.
采用LabVIEW技术完成对心电、呼吸、无创血氧和无创血压信号的采集与处理,而后通过MATLAB模糊测量系统对采集的人体生理信号进行模糊预测分析。通过实验检验了人体生理信号检测、处理和模糊预测分析方法的可靠性。LabVIEW技术对人体生理信号的模糊预测分析是有效的,可用于检测阻塞性睡眠呼吸暂停患者的生理状态信号。 相似文献
45.
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
46.
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
47.
江新 《中国激光医学杂志》1995,4(1):30-33
我院应用He-Ne激光治疗551例声带小结,取得较好疗效。为研究作用机理,我们进行了免疫功能测定、测温试验、He-Ne激光照射前后的间接喉镜检查、显微结构研究、抑菌试验和过氧化脂质测定。结果提示He-Ne激光照射治疗声带小结的机理为照射后喉部温度升高、血管扩张、血循环加快,从而增强局部营养,促进喉部粘膜生长、消除组织水肿,加速炎性渗出物和毒素的排泄。而He-Ne激光本身没有杀菌和抑菌作用。 相似文献
48.
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
49.
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
50.
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