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111.
目的探讨数据挖掘技术对周围型肺癌影像诊断规则提取的价值。方法收集58例经过临床病理证实的周围型肺癌病例,对其临床及CT表现属性进行标准化认定,输入数据库,分别采用自主开发的基于关联规则知识发现程序与通用数据分析工具ROSETTA中的粗糙集约简算法和遗传分类算法对58例周围型肺癌临床及影像学数据进行挖掘对比研究。结果由Johnson’s Algorithm粗糙集约简算法产生诊断规则51条,由ROSETTA遗传分类算法所产生的诊断规则有5千多条,基于关联规则的挖掘算法所产生的诊断规则有123条。这3种不同的数据挖掘方法产生的最重要的诊断规则基本上都将性别、年龄、位置、毛刺、形状、毛玻璃样密度等属性作为诊断周围型肺癌的主要依据。结论数据挖掘技术在医学影像诊断和鉴别诊断中具有潜在的应用价值。  相似文献   
112.
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2 immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves.  相似文献   
113.
Twenty-four-hour blood pressure and heart rate measurements were carried out in 14 newly diagnosed diabetics and in 28 diabetics with 5–13 years' duration of the disease; 8 healthy children were used as controls. Mean arterial blood pressure increased at night in 5, decreased slightly (less than 10%) in 5 and decreased markedly (more than 10%) in 18 diabetics with longer duration of the disease. The diurnal-nocturnal differences in heart rates were significantly lower in diabetics with relative "nocturnal hypertension" compared to the control group ( p < 0.05). A significant negative correlation was found between maximal arterial blood pressure during physical exercise and the diurnal-nocturnal differences in mean arterial blood pressure in diabetics ( r =−0.58; p < 0.02). In conclusion, we found elevated nocturnal blood pressure in a subgroup of children with longer duration of diabetes and without increased albumin excretion. However, longitudinal studies of blood pressure profiles are needed to identify the candidates for diabetic vasculopathy among diabetic children.  相似文献   
114.
Amputation in elderly and high-risk vascular patients   总被引:1,自引:0,他引:1  
Fifty-eight patients underwent lower limb amputation for arterial disease over a 30-month period. Mean age of the patients was 72 years. Cardiopulmonary and metabolic risk factors were present in the majority of the patients. Postoperative one-year and three-year mortality rates were 24, 40, and 76%, respectively. Contralateral amputation was required in one-third of the patients after a mean period of eight months. Only younger and healthier patients returned to a meaningful social life after appropriate prosthetic fitting. In view of the high mortality and morbidity rates, above-knee amputation seems a better choice than below-knee amputation in these elderly and high-risk patients.  相似文献   
115.
糖尿病肾病临床研究述评   总被引:54,自引:0,他引:54  
本文从中医病名、病因病机、诊断标准、临床分期、疗效评定、辨证论治、临床科研七个方面对糖尿病肾病的研究进行了述评。指出:糖尿病肾病的中医病名、诊断、分期及疗效评定标准亟待统一;立足于临床实际,参考现代医学有关认识,应用DME方法,开展糖尿病肾病临床和实验研究,深入探讨其病因病机和证治规律,在中医基本理论指导下,大胆创新,是提高临床疗效的关键;分期辨证论治较为符合疾病的发展规律,便于寻找防治糖尿病肾病的有效方法。  相似文献   
116.
The autonomic nervous control of cardiac function during active orthostatic load has been studied by measuring the power spectrum of heart rate fluctuations in 16 insulin-dependent diabetic patients and 14 age-matched control subjects. The patients were subdivided into two groups: 8 with normal respiratory sinus dysrhythmia (RSA+) and 8 with reduced respiratory sinus dysrhythmia (RSA-). In RSA- patients the total power (0.01-0.50 Hz) was significantly reduced compared with control subjects (4.7 versus 15.5 min-2, 2p less than 0.05) and the pattern of heart rate fluctuations was characterized by a relative increase in the low-frequency component (0.01-0.05 Hz) as compared with RSA+ patients and control subjects (45% versus 24% and 27%, both 2p less than 0.01). There was also a significant reduction in the high-frequency component (0.15-0.50 Hz) as compared with RSA+ patients and control subjects (17% versus 36% and 33%, both 2p less than 0.05). During standing, a significant increase in total power was found only in control subjects (2p less than 0.01) and the difference between control subjects, and RSA+ and RSA- patients reached significance (32.2 versus 15.1 and 12.7 min-2, 2p less than 0.02 and 2p less than 0.01). The pattern of heart rate fluctuations in RSA- patients showed no significant change on standing. These results suggest that the reduced overall heart rate variability in diabetic patients with cardiac autonomic neuropathy is associated with a typical heart rate fluctuation pattern.  相似文献   
117.
Severe axonal polyneuropathy with onset in the postpartum period   总被引:1,自引:0,他引:1  
We report two patients who presented severe polyneuropathy in the postpartum period. Electrophysiological studies evidenced an axonal process which was associated with proximal demyelination in the second patient. In both cases, a peripheral nerve biopsy showed severe axonal Wallerian-like degeneration and no feature of demyelination. The first patient had a dramatic loss of myelinated fibres, and severe disability persisted for several months. These two patients are different from cases of acute or chronic inflammatory demyelinating polyradiculoneuropathy previously reported in relation with pregnancy.  相似文献   
118.
We studied saccadic and smooth pursuit eye movements in 24 patients suffering from multiple sclerosis during disease worsening, before and after high-dose 6-methylprednisolone infusions. Quantitative evaluation of saccades was based on amplitude/duration and amplitude/peak velocity relationships, precision (i.e. the ratio of actual to desired saccade amplitude) and the latency, whereas smooth pursuit eye movements were studied using target velocity/performance index relationship. At basal recordings, 22/24 (91.7%) of the patients showed at lest one abnormality. Eleven of the 24 patients (45.8%) showed modification of one or several parameters: improvement in 6 patients, worsening in 2, coexistence of both trends in 3. Latency improvement was the only significant modification when patients were considered as a group. Neurophysiological modifications did not correspond to clinical changes.  相似文献   
119.
A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens.  相似文献   
120.
n-Hexane neuropathy was studied in 20 workers exposed for prolonged periods to this solvent, and with urinary 2, 5-hexanedione concentrations exceeding the biological exposure index recommended by the American Conference of Governmental Industrial Hygienists (5 mg/L) with a mean of 11.02 mg/L (range 5.3—24.2 mg/L). Although neurological examination did not detect significant anomalies in any of the patients, and the conduction velocity and F waves of all the nerves tested were normal, neurographic studies revealed significant differences in the amplitude of sensory nerve action potentials (SNAP) recorded from the sural (mean 14.0 μV), median (mean 17.3 μV), and ulnar (mean 7.9 μV) nerves when compared with normal values from healthy adults of the same age range, examined under identical conditions. The amplitude of the SNAP in sural and median nerves correlated significantly with the number of years worked. The notable decrease in mean amplitude of the SNAP appeared to reflect the primary neurotoxic effects of 2,5-hexanedione. © 1994 John Wiley & Sons, Inc.  相似文献   
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