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101.
Several single agonist/antagonist primary muscle spindle afferents were simultaneously recorded in chloralose anaesthetized cats. It was shown that their dynamic and static sensitivity to sinusoidal muscle stretches could be increased or decreased via the fusimotor system by extension and flexion of the contralateral hind limb as well as by stretch of ipsilateral muscles and stimulation of ipsilateral skin nerves. The results seem to support the hypothesis that the primary muscle spindle afferents convey complex multisensory messages to the central nervous system (CNS). 相似文献
102.
This paper presents the use of iterative dynamic programming employing exact penalty functions for minimum energy control problems. We show that exact continuously non-differentiable penalty functions are superior to continuously differentiable penalty functions in terms of satisfying final state constraints. We also demonstrate that the choice of an appropriate penalty function factor depends on the relative size of the time delay with respect to the final time and on the expected value of the energy consumption. A quadratic approximation (QA) of the delayed variables is much better than a linear approximation (LA) of the same for relatively large time delays. The QA improves the rate of convergence and avoids the formation of ‘kinks‘. A more general way of selecting appropriate penalty function factors is given and the results obtained using four illustrative examples of varying complexity corroborate the efficacy of the method. 相似文献
103.
Abstract: The use of neuromuscular electrical stimulation (NMES) for rehabilitation of gait in spinal patients is widely known. The best results can be obtained with the use of biomechanical sensors and a closed loop NMES system. One of the biggest problems faced in the design of control systems for closed-loop operation, in gait rehabilitation, is the variation of the mechanical conditions during the phases of gait. This work presents a new approach to ease the design of rule-based closed loop systems for operation in conditions such as gait rehabilitation. 相似文献
104.
P. K. C. Wang 《Optimal control applications & methods.》1995,16(5):305-320
The problem of controlling the temperature distribution in a solid cylinder whose length varies with time and with one end in contact with a constant temperature medium is considered. This problem is motivated from that of controlling the temperature and thermal gradient inside a crystal pulled from a melt by the Czochralski method. Boundary feedback controls are derived by considering the time rate of change of a cost functional involving the deviations of both the solid temperature and its gradient from their desired values. The derived feedback controls consist of spatially distributed proportional-plus-rate and lag compensators and a non-linear feedback control involving the temperature gradient at the cylinder surface and the velocity of the spatial domain boundary. The resulting feedback-controlled system has the property that the cost functional along any motion decreases monotonically to zero with time. A numerical scheme for solving the partial differential equation of the feedback-controlled system is proposed. Typical numerical results on the dynamic behaviour of the feedback-controlled system obtained by means of the proposed scheme are presented. 相似文献
105.
106.
Studies on the effectiveness of pain management have uniformly concluded that health care providers underestimate or undertreat pain. In the emergency department (ED) in which this study was conducted, physicians receive formal didactic and bedside teaching on pain recognition and management in order to heighten the awareness of patient's need for pain control. The purpose of this study was to determine if this outpatient pain management of patients with acute, painful conditions is better than that reported in the medical literature. In this prospective study, 110 adult patients who had an acute, painful diagnosis were telephoned 48 hours after discharge from the ED and asked if they felt their pain at home was well controlled. Patient satisfaction with pain control was higher (91%) than that reported in the medical literature. Also, pain medication was provided more frequently by this study's ED (95%). Education on pain awareness and treatment is a way to improve pain management. 相似文献
107.
腹腔镜卵巢穿刺内凝治疗多囊卵巢不孕症的临床研究 总被引:2,自引:0,他引:2
目的探讨腹腔镜卵巢穿刺内凝对多囊卵巢不孕症的治疗价值。方法151例腹腔镜卵巢穿刺内凝术(实验组)和151例开腹卵巢楔切术(对照组)治疗多囊卵巢不孕症配对对比研究。结果实验组的手术时间33.1±7.2min,术中失血15.6±4.7ml,总排卵率92.05%,总妊娠率49.67%,均优于对照组(P<0.01);术后雄激素、LH/FSH下降幅度小于对照组(P<0.01)。随时间推移,两组术后排卵巢、妊娠率均有下降倾向,而术后雄激素、LH/FSH则有逐渐回升的倾向。结论腹腔镜卵巢穿刺内凝术对多囊卵巢不孕症有较好的治疗效果 相似文献
108.
C. J. Bowden W. D. Figg N. A. Dawson O. Sartor R. J. Bitton M. S. Weinberger Donna Headlee Eddie Reed C. E. Myers M. R. Cooper 《Cancer chemotherapy and pharmacology》1996,39(1-2):1-8
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis,
but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer,
with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken
to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations
(275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous
infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted
in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed
in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml
for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed
this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response
rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses
were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy
with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred
with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well
tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional
therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but
it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment
of suramin’s activity in hormone-refractory prostate cancer.
Received: 9 June 1995/Accepted: 18 March 1996 相似文献
109.
脑络康缓释胶囊的制备工艺和体外释放度的研究 总被引:4,自引:0,他引:4
以羟丙甲基纤维素作为主要的缓释辅料,采用正交设计方法优化处方研制成脑络康缓释胶囊.以人参皂苷的累积释放量作为考察指标,按照<药典>规定的缓释制剂的释放度进行优选.结果:最佳的处方工艺即羟丙甲基纤维素216 mg,乙基纤维素24 mg,混合稀释剂132 mg,释放曲线符合Higuchi动力学模型. 相似文献
110.
目的 探讨在小学生中开展血吸虫病防治健康教育的新方法,提高其血防知识知晓率、行为正确率,以便控制血吸虫病流行。方法 选择如皋师范学院附小的951名小学生(及家长910名)作为实行渗透教育法实验组,选择条件相当的如皋陆桥和丰乐小学学生作为一般宣传和上课法对照组,研究结束后以基线调查结果为依据,评估研究效果,并作统计分析。结果 实验结果表明渗透法组学生的血防知识晓率和行为正确率干预前的3.1%和55.1%加学生负担,易为学生和教育部门接受具有很强的可操作性和推广价值。 相似文献