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21.
Objectives To analyze the relationship between lateral displacement of the mandible and scoliosis.
Methods From April 2002 through July 2003, we examined posteroanterior cephalometric radiographs and chest X-rays from 85 patients
with jaw deformities and a control group of 20 patients with no jaw deformities. To measure the lateral shift of the mandible,
we drew a horizontal baseline (X axis) on the cephalogram connecting the intersection of the external margins of the orbits and the most lateral points of
the greater wings of the sphenoid. A vertical baseline (Y axis) was then marked perpendicular to the X axis, intersecting the ethmoid crista galli. Then, we measured the lateral displacement of the mandibular mentum from the
Y axis. Displacement to the right was designated positive; that to the left was designated negative. Cobb's method was used
to measure scoliosis curves on chest X-rays; the direction of the curve was designated similarly.
Results Of the 85 patients with jaw deformity, 23 (27.1%) had a Cobb angle exceeding 10°. None of the control group had scoliosis
exceeding 10°. No correlation was found between the direction of mandibular displacement and the direction of scoliosis.
Conclusion This study suggests a relationship between jaw deformities and scoliosis, as scoliosis was found in 27.1% of the patients
with a main complaint of jaw deformity. 相似文献
22.
Introduction and Aims. Different self‐report methods tend to produce different estimates of alcohol consumption. The present study compares differences in rates and risk levels based on responses to a modified version of the Daily Drinking Questionnaire (m‐DDQ) and quantity‐frequency (QF) questions. Design and Methods. The sample comprised 2082 university students, 61% of whom were female and 39% male with a mean age of 23.5 years. An email containing an online link to a brief six‐question survey was emailed to students enrolled in participating faculties at the University of Wollongong, Australia. Current drinkers completed m‐DDQ and QF questions about alcohol consumption. Results. QF methods identified significantly lower estimates of consumption (Mean = 9.15, SD = 12.51) compared with m‐DDQ (Mean = 13.06, SD = 14.07). Allocation to risk categories based on the Australian Alcohol Guidelines were conducted for both the m‐DDQ and QF methods. Almost twice as many students were found to be drinking at levels considered risky using the m‐DDQ method compared with QF. In addition, the relative rank order of participants varied significantly between the two methods. Discussion and Conclusions. The m‐DDQ method identified higher rates of drinking and categorised almost twice as many individuals into risky categories of drinking compared with QF. Such variations have major implications for identification of risk groups in health promotion or prevention programs.[Utpala‐Kumar R, Deane FP. Rates of alcohol consumption and risk status among Australian university students vary by assessment questions. Drug Alcohol Rev 2009] 相似文献
23.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
24.
螺旋CT三维重建成像在先天性高肩胛症手术方式选择中的作用 总被引:4,自引:2,他引:2
[目的]探讨螺旋CT三维重建技术在先天性高肩胛症分度和手术方式选择中的作用。[方法]22例先天性高肩胛症术前应用螺旋CT对病变部位进行扫描并三维重建,测量以肩胛骨肩胛冈内侧缘为参照点,两侧肩胛骨高度差。根据测量结果依据Cavendish分度将其分类,并根据三维重建成像选择不同的矫形手术术式。[结果]本组22例病人,随访2—4年,外观及功能均有不同程度的改善,未出现神经、血管和椎体等的损伤。[结论]根据螺旋CT扫描和三维重建检查结果,术前即可直观的明确先天性高肩胛症的病变程度,相互关系,伴发畸形,患侧肩胛骨与正常对侧肩胛骨的外观差异等,便于手术操作方案的制定,避免了手术操作的盲目性,减少医源性并发症的发生。 相似文献
25.
Teruyuki Usuba Yutaka Suzuki Akira Kuramochi Hisao Tajiri Katsuhiko Yanaga 《Digestive endoscopy》2007,19(1):18-21
Background: Buried bumper syndrome (BBS) is a rare complication of percutaneous endoscopic gastrostomy (PEG). Along with the widespread use of the button‐type kit, BBS is encountered frequently. Methods: In the present study, we examined causes and treatments for BBS among 1400 patients who had undergone PEG. Results: The causes of BBS after PEG were classified into two categories: early causes consisted of wound infection, inappropriate size of kit and severe lordosis, while late causes were inappropriate exchange of kit, rough management or weight gain. The treatments for BBS could be determined by the degree of wound infection, fistula and burial of the bumper. Conclusion: We prepared a flowchart for replacement, by which BBS can be managed safely and quickly without surgical or endoscopic intervention. 相似文献
26.
M. I. James 《European journal of plastic surgery》1989,12(2):258-260
A technique is presented which allows the rapid precise harvesting of split-skin grafts in rats. This technique uses the skin
which would have been discarded in the formation of an open wound as a donor site thus reducing the overall assault on the
animal. 相似文献
27.
Abstract: We describe the use of restriction analysis on PCR-amplified DNA for detecting all B*27 subtypes except B*2710 and B*2711 (i.e. from B*2701 to B*2709). After detecting B*27 by Sty I, double digestions consisting of Sty I plus another informative enzyme led to subtype assignment. We used mismatched primers to create restriction sites when necessary. The method avoids group-specific amplifications and other laborious optimization procedures. It was successfully tested on a panel of well characterized cell lines covering different B*27 subtypes. Then, we studied a group of 57 ankylosing spondyiitis patients and 746 controls from the south of Spain. B*27 showed a very strong association with the disease (OR=211.27, P=\0˜7). B*2702 and B*2705 distribution in controls (20% and 77.1%, respectively) differed from previously reported data in the Spanish population. We unexpectedly found the B*2707 allele in our population (one control). 相似文献
28.
29.
本实验用自制纯钛两段式种植体,以一次手术法植入到狗的下颌前磨牙区,观察5个月,结果表明,观察期间内牙龈无炎症,种植体稳固,X线片显示种植体周围无透射区,镜下可见种植体表面与牙龈之间形成上皮附着样结构,与骨组织之间大多呈骨性愈合。提示了两段式种植体有两种设计和手术方式可供选择。骨内部分在开放的环境中也可达到骨性愈合。 相似文献
30.
应用蒙特卡洛法仿真辐射式金属换热器内的辐射传热过程,建立了换热器综合传热的数学模型,利用概率论原理,把辐射能迁移过程仿真为一定累积概率分面下的随机过程,该模型能较好地反映换热器内传热过程的真实情况,可以计算出换热器内烟气、筒壁、空气的温度和壁面热流分布,以及研究烟气进口温度、换热器筒径和狭逢宽度对换热效果的影响。 相似文献