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1.
The results of lumbar fusion in chronic low back pain (LBP) patients vary considerably, and there is a need for proper patient selection. Lumbosacral orthoses have been widely used to predict outcome, however, with little scientific support. The aim of the present study was to determine the value of a pantaloon cast test in selecting chronic LBP patients for lumbar fusion or conservative management. First, a systematic review of the literature was carried out in which two independent reviewers identified studies in Medline, Cochrane and Current Contents databases. Three papers met the selection criteria. In the only study with a control group, a significantly better outcome after fusion compared to conservative treatment was found in patients who reported significant pain relief while in a cast (i.e. a positive cast test). The results of lumbar fusion, however, were not significantly different for patients with a positive and those with a negative cast test. In addition to the review, a clinical cohort study of 257 LBP patients, who had been allocated to either lumbar fusion or conservative management by a temporary external transpedicular fixation trial, was performed. Prior to allocation, all had undergone a pantaloon cast test. Patients with no history of prior spine surgery and with a positive pantaloon cast test had a better outcome after lumbar fusion than those treated conservatively (P = 0.002, χ 2 test). In patients with previous spine operations the outcomes were poor and the test was of no value. From the literature and the present patient cohort, it was concluded that only in chronic LBP patients without prior spine surgery, a pantaloon cast test with substantial pain relief suggests a favorable outcome of lumbar fusion compared to conservative management. The test has no value in patients who have had previous spine surgery.  相似文献   
2.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
3.
The temporal structure of spike trains recorded from optic fibers and single units of the lateral geniculate nucleus (LGN) and primary visual cortex of the cat was studied with a novel method of inter-spike interval analysis. ON type relay cells of the LGN exhibited a multimodal interval distribution preferring a distinct interval (fundamental interval) and its multiples during the sustained light response, whereas most OFF cells showed a broad, unimodal distribution. The general pattern of the interval distribution was relatively independent of stimulus size and contrast and the degree of light adaptation. Simultaneously recorded S-potentials originating from the retinal input generally produced only a single peak at the fundamental interval length. Therefore, the multimodal interval distribution of LGN cells seems to be a result of intra-geniculate inhibition. Cortical cells also showed a weak tendency to fire with spike intervals similar to LGN cells. Therefore, the regular firing pattern observed at peripheral stages of the visual pathway can persist at higher levels and might promote the occurrence of oscillatory activity.  相似文献   
4.
一次阿扑吗啡注射对大鼠视觉辨别学习和工作记忆的影响   总被引:3,自引:1,他引:2  
目的探讨多巴胺受体激动剂 -阿扑吗啡对大鼠视觉辨别学习和工作记忆的影响。方法利用旋转T迷宫装置 ,通过食物强化 ,分别训练大鼠正常和逆反的视觉辨别学习任务。动物达到规定的标准次数后 ,腹腔注射 2mg/kg体重的阿扑吗啡 ,3 0分钟后观察药物对工作记忆的影响。 结果对于正常学习 ,阿扑吗啡注射组动物的正确次数与生理盐水对照组相比无显著性差异 ,且两组动物继续进行逆反学习训练 ,达到学习标准所需的总次数亦无显著性差异 ;对于逆反学习 ,阿扑吗啡注射组动物的正确次数较对照组显著降低。结论单独一次阿扑吗啡注射可能干扰大鼠逆反学习的工作记忆 ,但不影响正常学习的工作记忆和逆反学习的过程。  相似文献   
5.
Visual Basic作为一门可视化的高级编程语言,已经在各高等院校作为计算机基础教育的一门主干课程,随着多媒体技术、校园网建设和互联网技术的发展,原来滞后的教学方法势必影响高校计算机基础教学的效果。本文针对医学院校的计算机基础教育,着重探讨在新的历史时期Visual Basic的教学方法。  相似文献   
6.
图表比较教学法在微生物学教学中的应用   总被引:1,自引:0,他引:1  
图表比较教学法作为微生物学教学的直观教学手段在本科教学中占有十分重要的地位,是形象思维和抽象思维两种思维方式的协调统一。有利于反映各知识层面的内在联系,可使学生加深对知识的理解,增强分析和综合问题的能力,以利于提高教学质量。  相似文献   
7.
眼球破裂伤相关因素分析   总被引:5,自引:2,他引:3  
目的 观察眼球破裂伤的致伤原因、常见部位、视力预后。方法 眼科住院眼球破裂伤51例的回顾性总结分析。结果 眼球破裂伤的首要致伤因素是打架斗殴(占43%)、其次工伤(占20%)、家庭休闲和旅游误伤(占17%),交通事故(10%),其他(10%)。眼球破裂伤的常见部位是上方角膜缘(占45%),颞侧、鼻侧角膜缘和肌止点后巩膜(各占15%)。经过治疗,Ⅰ度破裂伤7/13获得0.02以上视力,Ⅱ度破裂伤9/20保留光感以上视力,Ⅲ度破裂伤1/18保留光感视力。结论 打架斗殴是眼球破裂伤首要致伤因素,常见伤口位置是上方角膜缘,眼球破裂伤的预后和损伤程度密切相关。  相似文献   
8.
Summary Spatial-frequency dependence of directional tuning and directional bias was compared, for both eyes, in four previously established discrete classes of binocular feline striate cortical neurones. Two classes (respectively direction-selective or bidirectional at optimal spatial frequency) were directionality invariant at all spatial frequencies. In the remaining two classes, both directionbiased at optimal spatial frequency, directional bias either altered or reversed with change in spatial frequency. In all four classes, the directional tuning of a majority of neurones sharpened at high spatial frequency through either eye, although the bandpass characteristics were sometimes dissimilar for the two eyes. All neurones were of the same type through either eye. Amongst the two classes of direction-biased neurones, the strength of bias was commonly different through the two eyes. Where reversal of bias occurred, that reversal took place at different spatial frequencies for each eye. Thus, the direction and orientation preferences of cortical neurones are fixed at optimal spatial frequency, but their envelope of tuning to a gamut of spatial frequencies is not. These differences are potentially related to binocular coding of visual perspective, including dynamic object rotation in visual space.  相似文献   
9.
 The ability voluntarily to stabilize the head in space during lateral rhythmic oscillations (0.59±0.09 Hz) of the trunk has been investigated during microgravity (μG) and normal gravity (nG) conditions (parabolic flights). Five healthy young subjects, who gave informed consent, were examined. The movements were performed with eyes open or eyes closed, during phases of either μG or nG. The main result was that head orientation with respect to vertical may be stabilized about the roll axis under μG with, as well as without vision, despite the reduction in vestibular afferent and muscle proprioceptive inputs. Moreover, the absence of head stabilization about the yaw axis confirms that the degrees of freedom of the neck can be independently controlled, as was previously reported. These results seem to indicate that voluntary head stabilization does not depend crucially upon static vestibular afferents. Head stabilization in space may in fact be organized on the basis of either dynamic vestibular afferents or a short-term memorized postural body schema. Received: 4 October 1995 / Accepted: 30 September 1996  相似文献   
10.
刘跃新  焦志友 《北京医学》1997,19(5):259-261
1993年11月至1996年5月应用改进的经尿道非接触式激光治疗前列腺增生120例,并对病人进行术前术后的症状评分,尿动力学,残余尿检查,随访病人1-24个月,结果显示病人无论是症状评分,还是尿流率,残余尿等各项指标均有明显的改善,此种手术具有简单,安全,副作用小,术后恢复快,治疗效果好等优点。  相似文献   
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