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91.
本文放弃传统的MSE准则,从信息论观点出发,发展了随机系统的一种最小熵(ME)控制方法,并从ME控制的等价性、控制限度、存在性、唯一性及必要条件等方面,研究了ME控制的合理性和实用性。ME方法是一种全局分析法,它不仅包含了MSE和MAP准则,且由于全文在整个推导中并未假定高斯性、线性和非时变等,因而原则上适用于诸如非高斯、非线性、时变等传统方法难以处理的复杂系统;不仅适用于工程系统,将其推广到决策、社会、经济等领域会更为自然和切合实际。  相似文献   
92.
The Low Vision Clinic at the Palmerston North Hospital has now been oerating for 70 years. Over the course of these ten years a number of factors have emerged which can be as readily applied to general ophthalmological practice as to low vision practice. The philosophy of low vision care is one of which all ophthalmologists should be aware and includes factors to be taken into account when dealing with children, people in the workplace, and everyday factors involved in daily living activities, all of which are equally relevant in routine ophthalmological practice. This paper endeavours to share some thoughts on these factors and also discusses means by which the visually handicapped can be helped in areas where specialist low vision services are not readily available.  相似文献   
93.
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   
94.
Recently, Korean people are consuming seaweeds almost 3.5 times more now than three decades ago. It is well known that seaweeds contain lots of soluble dietary fiber in addition to micronutrients such as β-carotene, iodine and some bioactive components. Seaweeds are considered to be effective for preventing chronic diseases including obesity, diabetes mellitus, atherosclerosis, cancer or constipation. This study was conducted to investigate the effect of seamustard intake on body weight gain, blood glucose level and lipid profiles in rats fed diets with different energy nutrient composition. Male Sprague-Dawley rats (average initial weight 103.7 g) were divided into groups for two experiments as follows; Control, M2.5 & M5 groups (Exp. I) and M5, M10, HCM5, HCM10, HFM5 & HFM10 groups (Exp. II). The rats were fed diet and water ad libitum for 4 weeks. In general, there was no significant difference in blood glucose and triglyceride concentration among groups. In Exp. I, serum LDL-cholesterol level of rats fed diet with 5% seamustard powder (M5) was significantly lower than that of control group, while HDL-cholesterol level, TC/LDL ratio and weight of adrenal gland were higher. In Exp. II, food intake, body weight gain and EER of high fat diet with 10% seamustard group (HFM10) were the lowest among groups. Except gastrocnemius muscle, all organ weights of HFM10 group were the lowest. Fecal cholesterol excretion and serum LDL-cholesterol concentration of HFM10 group were the highest, while serum HDL-cholesterol level was the lowest among groups. Interestingly, HDL-cholesterol concentration was the highest in HCM5 group among groups. From these results, it was suggested that seamustard intake might be more effective for body weight control, but not for improving blood lipid profiles in high fat diet than in high carbohydrate diet.  相似文献   
95.
CT引导下颈侧入路舌咽神经毁损术   总被引:4,自引:1,他引:3  
目的探讨CT引导下颈侧入路舌咽神经毁损术对舌咽神经痛及舌咽神经支配区顽固性疼痛的疗效. 方法 A组16例舌咽神经痛及B组12例舌咽神经支配区顽固性疼痛,采用CT引导经皮穿刺定位于茎突前缘第2颈椎水平,注入局麻药仅阻滞舌咽神经,注入7%苯酚甘油溶液0.8 ml. 结果 A组完全缓解率87.5%(14/16),总有效率100%(16/16),随访6个月无复发;B组完全缓解率50%(6/12),总有效率83.3%(10/12),随访6个月,复发6例(50.0%).2组均无严重并发症. 结论 CT介导下颈侧入路舌咽神经毁损术具有疗效可靠,定位准确,操作安全的特点,并有效减少严重并发症的发生.  相似文献   
96.
目的: 几乎没有研究报道妊娠高血压综合征 (妊高征 ) 患者尿蛋白对新生儿出生体重的影响, 该研究欲探讨妊高征患者不同水平尿蛋白对新生儿出生体重的影响关系。方法: 1997年 1月 ~2004年 6月期间, 住院分娩患中、重度妊高征产妇 136例, 对新生儿出生体重与各种因素进行回归分析及t检验分析。结果: 单变量回归分析尿蛋白、孕龄分别与新生儿出生体重有高度显著性关系 (P<0. 01); 尿蛋白和孕龄一起进入多元回归分析, 校正影响因素, 尿蛋白和孕龄仍然是影响新生儿出生体重显著性因素 (P<0 .01); 与妊高征尿蛋白 ( +) 比较, 尿蛋白 无显著性影响新生儿出生体重 (P>0. 05), 尿蛋白 有显著性影响新生儿出生体重 (P<0. 01)。结论: 新生儿出生体重与妊高征患者尿蛋白丢失有关, 尿蛋白 丢失将严重影响新生儿出生体重。  相似文献   
97.
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   
98.
The calculation of the extent of the ring scotoma around positive lenses, as conventionally taught to students of clinical optics, indicates that the scotoma is of a significant size. Using knife-edge lenses this study shows that the calculations are invalid due to the finite size of the eye's entrance pupil and in many instances the scotoma is shown not to exist. The effect noticed in clinical practice is probably largely due to the frame and the edging techniques used which add to the refractive scotoma which is present with high powered lenses, large apertures and/or small pupil sizes.  相似文献   
99.
100.
氟西汀与阿米替林治疗105例抑郁障碍病人的双盲对照试验   总被引:6,自引:4,他引:2  
目的:评价国产氟西汀的抗抑郁作用及安全性。方法:采用随机、双盲对照、多中心研究,分为国产氟西汀组57例(男性22例,女性35例;年龄40±s13a),口服氟西汀20mg,qd,阿米替林57例(男性27例,女性30例;年龄40±14a),口服阿米替林75mg,bid,疗程6wk。结果:氟西汀治疗抑郁障碍的疗效与阿米替林相当,总有效率分别为85%及92%(P>0.05);氟西汀组的主要副作用有口干、便秘、恶心、心动过速等,但较之阿米替林程度轻且发生率低。结论:氟西汀的抗抑郁作用与阿米替林相当,副作用少,服用方便。  相似文献   
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