坐位下行上胸段硬膜外穿刺31例临床分析

目的探讨坐位下行上胸段硬膜外穿刺的效果。方法择期行乳腺区段切除或胸前壁手术的患者31例,在助手的帮助下,按拟定好的要求摆好体位,并按程序进行硬膜外穿刺并留置硬膜外导管。记录局麻开始到置管成功所需要的时间和穿刺次数,手术结束后,拔除硬膜外导管并更换穿刺点敷料;在术后的第三天回访,以痛觉模拟评分（VSA）询问患者穿刺点局部疼痛情况并测量穿刺点敷料渗出面积。结果 31例患者中有30（96.8%）例患者在30min内穿刺成功,1例患者因为穿刺时间过长（〉30min）,改成全身麻醉,平均穿刺时间为（12.3±7.2）min,最短穿刺时间为3min,最长穿刺时间为28min;平均穿刺次数为（2.1±1.8）次,最多穿刺次数为6次,有8例患者一次穿刺成功;6例患者述在平卧位穿刺点有中度疼痛,其余患者均为轻度疼痛;穿刺次数与穿刺后VSA的疼痛评分正相关（r=0.525）;所有患者穿刺点均无明显出血,敷料渗出面积为（2.2±1.1）cm2,且呈正态分布。结论坐位下行上胸段硬膜外穿刺30min成功率高,无明显穿刺后疼痛和出血。     

不同体位固定术在胸腹部肿瘤放疗中的应用

目的分析与比较不同体位固定术在胸腹部肿瘤放射治疗中的应用。方法本文选择了70例接受胸腹部肿瘤放射治疗的患者进行研究,将这些患者随机分成两组,每组35例患者,其中一组为对照组,采用单纯常规的热塑膜体位固定术,而另外一组为观察组,则在采用常规的热塑膜体位固定术的同时,联合胸腹膜真空袋体位固定术。分析两种不同的体位固定术对胸腹部肿瘤放射治疗的位置精确度所造成的影响。结果两组相比,在对零位源皮距误差的影响方面,观察组为26%,明显好于对照组的46%。这两种体位固定术对零位源皮距误差的影响存在显著性意义(P<0.05)。结论热塑膜体位固定术联合胸腹膜真空袋体位固定术与常规的热塑膜体位固定术相比技术更加优越,精确度更加高。     

Contributions of vision–proprioception interactions to the estimation of time-varying hand and target locations

We investigated the relative importance of vision and proprioception in estimating target and hand locations in a dynamic environment. Subjects performed a position estimation task in which a target moved horizontally on a screen at a constant velocity and then disappeared. They were asked to estimate the position of the invisible target under two conditions: passively observing and manually tracking. The tracking trials included three visual conditions with a cursor representing the hand position: always visible, disappearing simultaneously with target disappearance, and always invisible. The target’s invisible displacement was systematically underestimated during passive observation. In active conditions, tracking with the visible cursor significantly decreased the extent of underestimation. Tracking of the invisible target became much more accurate under this condition and was not affected by cursor disappearance. In a second experiment, subjects were asked to judge the position of their unseen hand instead of the target during tracking movements. Invisible hand displacements were also underestimated when compared with the actual displacement. Continuous or brief presentation of the cursor reduced the extent of underestimation. These results suggest that vision–proprioception interactions are critical for representing exact target–hand spatial relationships, and that such sensorimotor representation of hand kinematics serves a cognitive function in predicting target position. We propose a hypothesis that the central nervous system can utilize information derived from proprioception and/or efference copy for sensorimotor prediction of dynamic target and hand positions, but that effective use of this information for conscious estimation requires that it be presented in a form that corresponds to that used for the estimations.     

情景教学在社区急救培训中的应用体会

目的提高全科医师岗位培训效果。方法在社区急救培训过程中采用情景教学与传统教学法进行对比研究。结果情景教学在提高学习主动性、积极性、参与性,培养学员分析问题、解决问题的能力等方面较对照组有显著差异（P〈0．01）。结论情景教学应用于社区急救培训可充分发挥学员的主体地位,保证岗位培训效果。     

Intrafraction motion of the prostate during external-beam radiation therapy: analysis of 427 patients with implanted fiducial markers

PURPOSE: To analyze the intrafraction motion of the prostate during external-beam radiation therapy of patients with prostate cancer. METHODS AND MATERIALS: Between August 2001-December 2005, 427 patients with Stage T3Nx/0Mx/0 prostate carcinoma received intensity-modulated radiation therapy treatment combined with position verification with fiducial gold markers. For a total of 11,426 treatment fractions (average, 27 per patient), portal images were taken of the first segment of all five beams. The irradiation time of the technique varied between 5-7 min. From these data, the location of gold markers could be established within every treatment beam under the assumption of minimal marker movement. RESULTS: In 66% of treatment fractions, a motion outside a range of 2 mm was observed, with 28% outside a range of 3 mm. The intrafraction marker movements showed that motion directions were often reversed. However, the effect was small. Even with perfect online position-correction at the start of irradiation, intrafraction motion caused position uncertainty, but systematic errors (Sigma) were limited to <0.6 mm, and random errors (sigma) to <0.9 mm. This would result in a lower limit of 2 mm for margins, in the absence of any other uncertainties. CONCLUSIONS: Intrafraction motion of the prostate occurs frequently during external-beam irradiation on a time scale of 5-7 min. Margins of 2 mm account for these intrafraction motions. However, larger margins are required in practice to accommodate other uncertainties in the treatment.     

Health-related quality of life in patients with locally advanced prostate cancer after 76 Gy intensity-modulated radiotherapy vs. 70 Gy conformal radiotherapy in a prospective and longitudinal study

PURPOSE: To compare quality of life (QoL) after 70 Gy conformal radiotherapy with QoL after 76 Gy intensity-modulated radiotherapy (IMRT) in patients with locally advanced prostate carcinoma. METHODS AND MATERIALS: Seventy-eight patients with locally advanced prostate cancer were treated with 70 Gy three-field conformal radiotherapy, and 92 patients received 76 Gy IMRT with fiducial markers for position verification. Quality of life was measured by RAND-36, the European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30(+3)), and the prostate-specific EORTC QLQ-PR25, before radiotherapy (baseline) and 1 month and 6 months after treatment. Quality of life changes in time (baseline vs. 1 month and baseline vs. 6 months) of > or =10 points were considered clinically relevant. RESULTS: Differences between the treatment groups for QoL changes over time occurred in several QoL domains. The 76-Gy group revealed no significant deterioration in QoL compared with the 70-Gy group. The IMRT 76-Gy group even demonstrated a significantly better change in QoL from baseline to 1 month in several domains. The conformal 70-Gy group revealed temporary deterioration in pain, role functioning, and urinary symptoms; for the IMRT 76-Gy group a better QoL in terms of change in health existed after 1 month, which persisted after 6 months. For both treatment groups temporary deterioration in physical role restriction occurred after 1 month, and an improvement in emotional role restriction occurred after 6 months. Sexual activity was reduced after treatment for both groups and remained decreased after 6 months. CONCLUSIONS: Intensity-modulated radiotherapy and accurate position verification seem to provide a possibility to increase the radiation dose for prostate cancer without deterioration in QoL.     

An Unusual Lateral Incisor

Abstract

A case is reported in which the morphology of the tooth present in the right maxillary lateral incisor region suggests a diagnosis of hypo-hyperodontia.     

ECAT ART — a continuously rotating PET camera: Performance characteristics, initial clinical studies, and installation considerations in a nuclear medicine department

Advances in fully three-dimensional (3D) image reconstruction techniques have permitted the development of a commercial, rotating, partial ring, fully 3D positron emission tomographic (PET) scanner, the ECAT ART. The system has less than one-half the number of bismuth germanate detectors compared with a full ring scanner with the equivalent field of view, resulting in reduced capital cost. The performance characteristics, implications for installation in a nuclear medicine department, and clinical utility of the scanner are presented in this report. The sensitivity (20 cm diameter×20 cm long cylindrical phantom, no scatter correction) is 11400 cps·kBq^–1·ml^–1. This compares with 5800 and 40500 cps·kBq^–1·ml^–1 in 2D and 3D respectively for the equivalent full ring scanner (ECAT EXACT). With an energy window of 350–650 keV the maximum noise equivalent count (NEC) rate was 27 kcps at a radioactivity concentration of ~15 kBq·ml^–1 in the cylinder. Spatial resolution is ~6 mm full width at half maximum on axis degrading to just under 8 mm at a distance of 20 cm off axis. Installation and use within the nuclear medicine department does not appreciably increase background levels of radiation on gamma cameras in adjacent rooms and the dose rate to an operator in the same room is 2 µSv·h^–1 for a typical fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) study with an initial injected activity of 370 MBq. The scanner has been used for clinical imaging with¹⁸F-FDG for neurological and oncological applications. Its novel use for imaging iron-52 transferrin for localising erythropoietic activity demonstrates its sensitivity and resolution advantages over a conventional dual-headed gamma camera. The ECAT ART provides a viable alternative to conventional full ring PET scanners without compromising the performance required for clinical PET imaging.     

3－酮－地索高诺酮中间体的合成

本文经几步反应，以化学方法引入１１β-位羟基，通过波谱分析，确证了所得物的化学结构。用该化学合成法引入１１β-位羟基的收率较原报道的有关微生物发酵法为高，而且合成方法简单，是一种比较好的化学引入１１位羟基的合成方法，为今后有关化合物的合成打下了基础。