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11.
The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
12.
目的:对神经精神狼疮(NPLE)的临床表现、辅助检查及预后进行总结。方法:对37例伴中枢神经系统损害的SLE患者进行回顾性分析。结果:①有局灶性症状及癫痫反复发作者预后差;②MRI检查的阳性率高,但定位缺乏特异性;③神经精神狼疮(NPLE)患者的脑脊液(CSF)蛋白升高,尤其是IgG的升高是其主要特点。结论:NPLE患者症状不同预后有明显差异,MRI检查和脑脊液蛋白的测定为NPLE的诊断、治疗提供依据。  相似文献   
13.
本文对肺部三种疾病1536例患者的病历资料,按病种作了统计归类。运用模糊数学原理建立了征候一疾病间的模糊关系矩阵,用参量加权模糊综合评判模型,对肺部三种疾病鉴别诊断的符合率达82.91%以上,因此认为文中建立的模型,对肺部三种疾病鉴别诊断具有参考价值。  相似文献   
14.
The zurich study     
Summary This study describes sleep behaviour and insomnia in a representative cohort of a Swiss population. Interviews were carried out prospectively from age 20–21 to 27–28 years, starting with 292 males and 299 females. Females usually go to bed earlier and sleep 30 min longer than males. Taking into account length and periodicity of insomnia we can distinguish occasional insomnia (OI), repeated brief insomnia (RBI), and continued insomnia (CI), defined by operational criteria. The prevalence of sleep problems is stable from age 21–28, at 36%–40%. CI (prevalence 8%–10%) and RBI (13%–19%) are both medical problems in terms of treatment by professionals (10%–17%) or self-medication (7%–12%). The majority of insomniacs cope with sleep problems in various other ways. Frequency and patterns of symptoms of insomnia are described.The authors thank P. J. Clayton, M.D., University of Minnesota, Minneapolis, for advice and critical suggestions and for the coining of the terms repeated brief insomnia and continued insomnia.Project supported by grant 3.948.0.85 from the Swiss National Science Foundation.Parts of this article were presented on the occasion of the inauguration ceremony of the Department of Psychiatry of the University of Mainz on April 2 and 3, 1987  相似文献   
15.
Axial rotation component of thoracic scoliosis   总被引:3,自引:0,他引:3  
The axial rotation (rotation about a vertical axis) of the vertebrae, of the ribs, and of the back surface are components of the deformity recognized clinically as the "rib hump" in thoracic scoliosis. Relationships of these rotations to the lateral deviation and lateral curvature of the spine were studied in 40 patients with idiopathic scoliosis. Stereoradiographs of the spine and rib cage were used to measure three components of axial rotation: rotation of the vertebrae, of the rib cage, and of the plane of maximum curvature of the spine. Stereotopographs of the back surface were digitized to measure the axial rotation of the back surface. In individual patients, there were high correlations of all components of axial rotation at each spinal level with the corresponding vertebral lateral deviation from the spinal axis. By regression analyses of the maximum values of each rotation in each curve, the rotation of the apex vertebra was found to be generally of lesser magnitude than the rotation of the plane of maximum curvature of the spine and in an opposite sense in kyphotic curves. The rib cage rotation was generally of lesser magnitude than the vertebra rotation, and the back surface rotation was less than both of these skeletal rotations. Vertebra rotation correlated most closely with lateral deviation of the spine. Simple segmental coupling of axial rotation and lateral bending could not be responsible for this axial rotation.  相似文献   
16.
The remodeling of the pulmonary arterial tissue in response to a step change of the oxygen concentration in the gas in which a rat lives was recorded as function of time and function of O2 concentration. Three steps of changing from 20.9% to 17.2%, 13.6%, and 10% O2 were imposed. Earlier work in our laboratory has shown that pulmonary arterial tissue remodeling is significant in the first 24 h after a step change of oxygen tension. Hence we made measurements in this period. Furthermore, data were obtained for tissue remodeling of circumferential and axial lengths of the pulmonary arteries. We recorded the activities of gene expressions in the lung tissues by microarray, determined the dose response curves of gene expression in the homogenized whole lungs with respect to four levels of O2 concentration, and obtained the time courses of gene expression in the lung parenchyma in 30 days after a step decrease of O2 concentration from 20.9% to 10%. We would like to suggest that the correlation of gene expression with physiological function parameters, i.e., time, O2 tension, blood pressure, opening angle, wall thicknesses, etc., is the way to narrow down the search for specific genes for specific physiological functions. © 2001 Biomedical Engineering Society. PAC01: 8719Uv  相似文献   
17.
BACKGROUND Schwannoma is a benign, encapsulated and slowly growing tumor originating from Schwann cells and is rarely seen in the peripheral nerve system. Typical symptoms are soreness, radiating pain and sensory loss combined with a soft tissue mass.AIM To evaluate pre-and postoperative symptoms in patients operated for schwannomas in the extremities and investigate the rate of malignant transformation.METHODS In this single center retrospective study design, all patients who had surgery for a benign schwannoma in the extremities from May 1997 to January 2018 were included. The location of the tumor in the extremities was divided into five groups; forearm, arm, shoulder, thigh and leg including foot. The locations of the tumor in the nerves were also categorized as either; proximal, distal, minor or major nerve. During the pre-and postoperative clinical evaluation, symptoms were classified as paresthesia, local pain, radiating pain, swelling, impairment of mobility/strength and asymptomatic tumors that were found incidentally(with magnetic resonance imaging). The patients were evaluated after surgery using the following categories: Asymptomatic or symptomatic patients(radiating and/or local pain) and those with complications. The follow up period was from the time of surgery until last examination of the particular physician. Multivariate logistic regression analysis was performed to identify independent prognostic factors for postoperative significant symptoms at follow-up.RESULTS We identified 858 cases from the institutional pathology register. We excluded cases with duplicate diagnoses(n = 407), pathology not including schwannomas(n = 157), lesions involving the torso, spine and neck(n = 150) leaving 144 patients for further analysis. In this group 99 patients underwent surgery and there were five complications recorded: 2 infections(treated with antibiotics) and 3 nerve palsies(2 involving the radial nerve and one involving the median nerve) that recovered spontaneously. At the end of follow-up, 1.4 mo(range 0.5-76) postoperatively, we recorded a post-operative decrease in clinical symptoms: Local pain 76%(6/25), radiating pain 97%(2/45), swelling 20%(8/10). Symptoms of paresthesia increased by 2.8%(37/36) and there was no change in motor weakness before and after surgery 1%(1/1). Multivariate analysis showed that tumors located within minor nerves had a significantly higher prevalence of postoperative symptoms compared with tumors in major nerves(odds ratio: 2.63; confidence intervals: 1.22-6.42, P = 0.029). One patient with schwannoma diagnosed by needle biopsy was diagnosed to have malignant transformation diagnosed in the surgically removed tumor. No local recurrences were reported.CONCLUSION Surgery of schwannomas can be conducted with low risk of postoperative complications, acceptable decrease in clinical symptoms and risk of malignant transformation is low.  相似文献   
18.
目的 了解2型糖尿病患者迷走神经病变,从而为糖尿病神经病变临床诊疗提供参考依据。方法 收集2020年1月—2021年6月在南京医科大学附属无锡人民医院内分泌科接受诊治的51例2型糖尿病患者和42例健康志愿者临床资料进行分析。采用自主神经症状(SAS)量表对2型糖尿病患者自主神经系统症状进行评价;采用超声测定迷走神经横断面面积,比较2型糖尿病患者和健康对照迷走神经横断面面积差异,分析迷走神经横断面面积与2型糖尿病患者临床特征间的关联。结果 2型糖尿病患者和健康对照者性别构成、年龄、身高、有吸烟史比例差异均无统计学意义(P > 0.05),但2组研究对象体质量(t = 4.52,P < 0.01)、体质指数差异有统计学意义(t = 5.21,P < 0.01)。51例2型糖尿病患者中,37例出现自主神经系统症状,平均出现3.7 ±0.9种(1~9种)自主神经系统症状,总体症状影响评分平均为10.5 ±3.2分(0~25分)。2型糖尿病患者左、右侧迷走神经横断面面积平均为(1.55 ±0.44)、(1.97 ±0.66) mm2,显著大于健康对照的(1.37 ±0.37)、(1.61 ±0.540) mm2t = 2.20,P < 0.05;t = 2.87,P < 0.01)。Pearson相关分析显示,迷走神经横断面面积与2型糖尿病患者及健康对照年龄、身高、体质量、体质指数均无统计学关联(P > 0.05),且与2型糖尿病患者糖尿病病程、自主神经系统症状数量及SAS量表总体症状影响评分均无统计学关联(P > 0.05)。结论 2型糖尿病患者存在迷走神经增粗,迷走神经超声可用于自主神经病变早期检测。  相似文献   
19.
This paper presents further results from a study of married women in Edinburgh who had just suffered an adverse experience: either their husband's non-fatal myocardial infartion, their husband's death or their own arrival in a Women's Aid refuge for battered women. Interviews were carried out 4–6 weeks following the adverse experience and, where possible, again approximately 3 months later. Symptoms were assessed using the 30-item General Health Questionnaire and criterion-based measures of depression and anxiety derived from it. The extent and nature of crisis support from household members and from groups of people outside the household, and also of failures in expected support, was measured at first interview. A modified version of Tyrer and Alexander's (1979) personality schedule was administered at the follow-up interview, and the resulting personality data were then reduced to six factors using principal components analysis. An interviewer assessment of how well the subject was coping was made at both interviews. The vast majority of the sample received extensive practical and emotional support from family and friends, and perhaps because such positive support was so prevalent, variations in it seemed to have little effect on symptoms. However, subjects who were unexpectedly let down or criticised by friends or family tended to show higher symptom levels, although, surprisingly, this was less true for the bereaved wives than for the others. The six personality factors that emerged were labellednervousness (similar to neuroticism)impulsivity, social withdrawal, helplessness, inferiority andaggressiveness. There was evidence that subjects high on nervousness remained symptomatic longer following the adverse experience. The aggressiveness factor showed a curvilinear trend with high and low aggressives showing higher symptom levels than middle aggressives. However, for the coronary wives the trend was linear with low aggressives having high symptoms. Subjects low on impulsivity were more affected by being let down by friends and family. The interviewer-assessed coping measure was linearly related to nervousness and showed a curvilinear relationship with aggressiveness.  相似文献   
20.
Summary A 29 year-old woman with SLE was admitted to our department due to severe remitting headaches. Following investigation a high degree of intra cranial pressure was determined.Several years ago a similar finding was diagnosed, and the disease was brought into remission by the administration of periodical pulses of high dose intravenous immunoglobulins.Benign intracranial hypertension (BIH) is an uncommon presentation of neuropsychiatric SLE. In this patient several risk factors of BIH (obesity, steroid therapy, and SLE) assembled and elicited a severe presentation of the disorder which became more resistant to therapy. Several pathogenic pathways tie BIH with SLE as thrombotic obliteration of cerebral arteriolar and venous systems and immune complex deposition within the arachnoid villi (that are responsible for CSF absorption). As shown in this case report of BIH, clinical findings do not always parallel various imaging techniques as MRI and CT brain scans.  相似文献   
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