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91.
雷公藤双层栓的研制   总被引:7,自引:0,他引:7  
介绍了雷公藤双层栓的制备和质量检查。雷公藤双层栓的上层为空白层,下层为含药层。空白层可有效地阻止后端所释药物向上扩散,从而避免相当部分药物经门肝系统吸收,因此可明显提高其生物利用度。  相似文献   
92.
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   
93.
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   
94.
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   
95.
Neutrophil bactericidal activity was assessed in patients with type 1 (n=45) and Type 2 diabetes mellitus (n=68) and non-diabetic control subjects (n=40) by measurement of whole blood chemiluminescence. Though chemiluminescence values tended to be highest in the non-diabetic subjects these differences were not statistically significant (mean ± SD) (2.73 ± 1.65 mV (controls), 2.33 ± 1.41 mV (Type 1 diabetes) and 2.38 ± 1.12 mV (Type 2 diabetes), F=1.12, p=0.33). Significant negative correlations were evident, however, in patients with both Type 1 and Type 2 diabetes between chemiluminescence and glycated haemoglobin (rs=-0.35, p=0.005 (Type 1), rs=-0.45, p=0.002 (Type 2), fructosamine (rs=-0.36, p=0.003 (Type 1), rs=-0.42, p=0.004 (Type 2)), and random blood glucose (rs=-0.25, p=0.04 (Type 1), rs=-0.48, p=0.001 (Type 2)). Changes in whole blood chemiluminescence in a further group of 10 patients with Type 2 diabetes mellitus commenced on insulin therapy were followed for 21 days. Serum fructosamine concentrations fell significantly over this time (524 ± 58 μmol l?1 to 405 ± 47 μmol l?1, p<0.001), however, although chemiluminescence values tended to rise these changes were not statistically significant (1.01 ± 0.38 mV to 1.60 ± 0.91 mV, S=4.24, df=5, p=0.52). These results suggest that impaired neutrophil bactericidal function is associated with poor blood glucose control. While it is likely that neutrophil bactericidal function will improve as blood glucose control improves, further studies are required both to confirm this and to demonstrate a reduction in the incidence of clinical bacterial infection.  相似文献   
96.
Multi-joint limbs permit a flexible response to unpredictable events   总被引:1,自引:0,他引:1  
The human arm is kinematically redundant, which may allow flexibility in the execution of reaching movements. We have compared reaching movements with and without kinematic redundancy to unpredictable double-step targets. Subjects sat in front of a digitising tablet and were able to view an arc of four targets reflected in the mirror as virtual images in the plane of the tablet. They were instructed to move, from a central starting point, in as straight a line as possible to a target. In one-third of trials, the target light switched to one of its neighbours during the movement. Subjects made 60 movements using shoulder, elbow and wrist and then another 60 movements in which only shoulder and elbow movement were allowed. By restraining the wrist, the limb was made non-redundant. The path length was calculated for each movement. In single-step trials, there was no significant difference between path lengths performed with and without wrist restraint. As expected there was a significant increase in path length during double-step trials. Moreover this increase was significantly greater when the wrist was restrained. The variability across both single- and double-step movements was significantly less while the wrist was restrained. Importantly the performance time of the movements did not alter significantly for single-step, double-step or restrained movements. These results suggest that the nervous system exploits the intrinsic redundancy of the limb when controlling voluntary movements and is therefore more effective at reprogramming movements to double-step targets. Received: 24 March 1997 / Accepted: 7 July 1997  相似文献   
97.
1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator.  相似文献   
98.
This experiment was undertaken to provide a pharmacological characterization of performance on a task involving food-related instrumental and consummatory behavior. Rats were tested in an operant chamber in which there was a choice between pressing a lever to receive a preferred food (Bioserve pellets) or approaching and consuming a less-preferred food (Lab Chow). The lever pressing schedule was a fixed ratio 5 (FR5). Rats usually pressed the lever at high rates to obtain the preferred food, and typically ate little of the lab chow even though it was freely available in the chamber concurrently with the lever pressing schedule. Previous work has shown that injection of dopamine (DA) antagonists, or depletion of DA in the nucleus accumbens, caused a substantial shift in behavior such that lever pressing was reduced but chow consumption increased. In the present study it was shown that the DA antagonist haloperidol decreased lever pressing and increased chow consumption at doses of 0.1 and 0.15 mg/kg. The D1 antagonist SCH 23390 (0.05, 0.1 and 0.15 mg/kg) and the non-selective DA antagonistcis-flupenthixol (0.3 and 0.45 mg/kg) decreased lever pressing and produced substantial increases in chow consumption. The D2 antagonist sulpiride decreased lever pressing, but produced only slight increases in chow intake at the highest dose. Pentobarbital reduced lever pressing and increased chow consumption at 10.0 mg/kg. The muscarinic agonist pilocarpine produced dose-related decreases in lever pressing, but failed to increase chow consumption. Amphetamine produced dose-related decreases in both lever pressing and chow consumption. These results indicate that low/moderate doses of the DA antagonists haloperidol,cis-flupenthixol and SCH 23390 can suppress lever pressing in doses that leave the animal directed towards food acquisition and consumption.  相似文献   
99.
Preventing accidental injury to young children in the home using volunteers   总被引:1,自引:0,他引:1  
Accidental injury in the home is a major cause of death andill-health among young children. Reducing home safety hazardsby the use of safety devices such as stair barriers and safetytaps has the potential to prevent home injuries. Little is knownabout levels of home safety hazards or how to encourage parentsto reduce hazards. The Safe Place Project examined parents'knowledge of home safety and the prevalence of safety hazardsin homes where there were young children. The study also evaluatedthe effectiveness of a low-cost strategy aimed at reducing homesafety hazards. The strategy used trained volunteers to providehome safety checks and tailored safety education in conjunctionwith increasing the availability of home safety devices. Onehundred and six families with young children participated inthe project. Some homes contained many hazards, with 43% ofthe sample having more than 10 home safety hazards. At follow-up,the intervention group showed a significant reduction in homehazards and a trend towards an increase in knowledge of homesafety.  相似文献   
100.
A suboptimal controller for a class of discrete-time systems is presented. The controller is derived by first solving ‘off-line’ a simplified optimal control problem obtained by neglecting part of the system state and by considering a larger time step, then by solving ‘on-line’ at each time step an optimization problem based on the results of the previously solved ‘off-line’ problem. A simple numerical example is presented to illustrate the control scheme.  相似文献   
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