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81.
Abstract. Objectives. To evaluate the efficacy of self-administered subcutaneous sumatriptan in the acute treatment of early-morning migraine attacks. Design. A double-blind, randomized, placebo-controlled, cross-over study. Setting. Thirteen neurology centres in France. Subjects. Patients of either sex, 18–65 years old, with two to six attacks of migraine (according to the International Headache Society (IHS) criteria, with or without aura) per month, of which at least two had to be early-morning migraine attacks. One-hundred-and-one patients were included, 96 being evaluable for the first attack and 81 for the cross-over design. Interventions. Two migraine attacks (grade 2/3) were treated with sumatriptan (6 mg) or placebo, with an optional second injection 1–24 h later. Main outcome measures. The primary end-point was headache relief: reduction in headache severity from grade 2/3 (moderate/severe) to grade 1/0 (mild/none) 2 h after treatment. Results. Sumatriptan was superior to placebo for headache relief (32 [78%] vs. 11 [28%] at the first attack; 29 [73%] vs. 8 [20%] at the second; P < 0.001). Because of a significant carry-over effect for some of the secondary end-points, a parallel-group analysis of the first attack was performed, which confirmed a significantly higher efficacy of sumatriptan for all end-points: pain-free rate (22 [46%] vs. 7 [15%]; P = 0.001) and use of a second injection (26 [53%] vs. 38 [81%]; P = 0.004). Sumatriptan was preferred by 74% of patients vs. 17% for placebo, and 9% expressed no preference (P < 0.0001). After complete relief, headache reappeared in 8/23 (35%) patients with sumatriptan and 3/7 (43%) with placebo. Adverse events were significantly more frequent with sumatriptan but they were minor and transient. Conclusion. Subcutaneous sumatriptan auto-injection is an effective and well-tolerated acute treatment of early-morning migraine attacks allowing earlier return to normal activity.  相似文献   
82.
本文定义了一类“近乎双线性”系统。可用以近似一类奇异摄动双线性系统,而且可以描述某些实际工业对象。并发现其控制器的设计较方便。文中还给出了一种简单的反馈控制器的设计方法。又对一类多输入双线性系统,提出一种设计反馈控制器的改进方案,根据Lyapunov定理得到一非线性反馈控制律。以上设计方法分别对某合成氨反应器作了应用研究,仿真结果表明了方法的有效性。  相似文献   
83.
目的 北京市某三级医院为提升全员应对突发公共卫生事件的应急处置能力,最大限度保障职工职业安全,实现所有工作人员零感染,开展全员职业培训与考核。方法 采用ISD(instructional system design)模型进行培训课程的系统设计,对全院人员在线学习、电子试卷考核和现场培训、考核结果使用Excel、SPSS 22.0进行分析。结果 参加培训人员经培训后平均得分由84升至100,答题时间由平均308 s缩短为179 s,不同职称人员培训前后考核分数存在差异,不同部门间人员培训前后的考核分数存在差异。结论 在突发公共卫生事件发生时,全员培训及考核是必要的,应用ISD模型有助于快速制定培训方案。在线学习考核的应用是应急全员培训的首选有效方式。  相似文献   
84.
针对医学微生物学实验线上教学面临的诸多难题,本研究采取线上直播+操作视频+虚拟实验的授课模式,通过操作视频和虚拟实验弥补了操作上的缺口;考核模式采用紧扣操作流程的主观型思考题+实验设计+文献综述(围绕传统实验由于条件所限无法开展的临床检验重头技术或新技术,如质谱分析、荧光定量PCR、G实验等展开)的模式,从而可以较大限度了解学生对教学目标的掌握程度和综合应用、创新性思维等能力。学生调查问卷显示,大部分学生对线上实验教学模式持肯定态度,学生作业的完成质量表明大部分学生学习效果良好。  相似文献   
85.
目的 评价金茵利胆胶囊的体外抗炎活性,并研究其抗炎谱效关系。方法 建立LPS诱导的RAW264.7细胞炎症模型,通过检测细胞上清中NO、TNF-α和IL-6等指标的含量来评价金茵利胆胶囊的抗炎活性。在此基础上,采用均匀设计法制备金茵利胆胶囊组成饮片的不同配伍样本,采用高效液相法建立均匀设计样品的指纹图谱,对均匀设计样品进行抗炎活性测定;以细胞上清液中NO、TNF-α和IL-6的抑制率为药效指标,与共有峰峰面积经灰色关联分析构建抗炎谱效关系。结果 金茵利胆胶囊提取物(0.25~1.00 mg/mL)能显著降低LPS诱导的RAW264.7细胞分泌NO、TNF-α和IL-6。经对照品比对指认出其中7个色谱峰,分别为新绿原酸(9号峰)、绿原酸(13号峰)、隐绿原酸(14号峰)、1, 3-二咖啡酰奎宁酸(16号峰)、对羟基苯乙酮(17 号峰)、柚皮苷(21 号峰)、新橙皮苷(23 号峰)。抗炎谱效关系结果表明,共有峰均具有一定的抗炎贡献度,其中共有峰峰21(柚皮苷)、峰23(新橙皮苷)与3个细胞炎症指标的关联度均大于0.74。结论:金茵利胆胶囊发挥抗炎作用是多种成分共同作用的结果,为金茵利胆胶囊抗炎药效物质基础及其质量控制提升提供参考。  相似文献   
86.
A study of 13 homes for elderly people examining the effect of the environment on demented residents looked into the complexity of the design from the residents' point of view. Two principal tools were used in this investigation: ‘route diagrams’, which describe a resident's use of the home, and a measure devised to indicate each resident's ability to find her way around the home. These are described and the relationship between them explored. From this the following tentative conclusions are drawn:
  • (i) The variables that influence a resident's ability to find her way around differ between group and communally designed homes.
  • (ii) It would appear that group homes provide a more favourable design, especially in the case of physically frail demented elderly people.
  • (iii) In group homes, the level of lighting is an important aid to a demented person in finding her way around.
  • (iv) In communal homes, residents seem most able to find their way around homes that have been adapted from older premises.
  • (v) In both types of home, ‘meaningful decision points’ can be seen as aids to a resident finding her way around.
  相似文献   
87.
Several transdermal contraceptive device (TCD) formulations were developed to provide a dual-controlled transdermal delivery of levonorgestrel (LN), a potent progestin, and 17-estradiol (E2), a natural estrogen. Using a sensitive HPLC method, the in vitro release and skin permeation profiles of LN and E2 from various TCD formulations were simultaneously characterized in the hydrodynamically well-calibrated Valia–Chien skin permeation cells and both were found to follow zero-order kinetics. The rates of drug release and skin permeation were observed to vary significantly depending upon some formulation parameters. Six-month stability studies were performed on seven formulations at room and elevated temperatures (37 and 45°C), and two (Formulations 4 and 5) were found to be acceptable, based on drug recovery, release rate, and skin permeation rate data. Judging from the 6-month accelerated stability studies, it is projected these two formulations will have shelf-life of at least 2 years. As a result of development of an efficient manufacturing process, Formulation 4 was selected for further evaluation. One-week primary skin irritation evaluation in 6 rabbits indicated that Formulation 4 is nonirritating, and it was thus selected for Phase I clinical bioavailability/dose proportionality studies in 12 healthy female volunteers of child-bearing age. Results of pharmacokinetic and pharmacodynamic analyses demonstrated that it is capable of achieving and maintaining a steady-state serum level of LN throughout the 3-week treatment period by weekly applications of one or two TCD patches (10 or 20 cm2). A dose proportionality was obtained in the serum drug levels, daily dose delivered, and contraception efficacy. An excellent correlation was obtained for the rates of transdermal delivery determined by the in vitro studies using human cadaver skin, the in vivo studies in rabbits, and the clinical studies in living subjects.  相似文献   
88.
In the study, an efficient method to perform supervised classification of surface electromyogram (EMG) signals is proposed. The method is based on the choice of a relevant representation space and its optimisation with respect to a training set. As EMG signals are the summation of compact-support waveforms (the motor unit action potentials), a natural tool for their representation is the discrete dyadic wavelet transform. The feature space was thus built from the marginals of a discrete wavelet decomposition. The mother wavelet was designed to minimise the probability of classification error estimated on the learning set (supervised classification). As a representative example, the method was applied to simulate surface EMG signals generated by motor units with different degrees of short-term synchronisation. The proposed approach was able to distinguish surface EMG signals with degrees of synchronisation that differed by 10%, with a misclassification rate of 8%. The performance of a spectral-based classification (error rate approximately 33%) and of the classification with Daubechies wavelet (21%) was significantly poorer than with the proposed wavelet optimisation. The method can be used for a number of different application fields of surface EMG classification, as the feature space is adapted to the characteristics of the signal that discriminate between classes. An erratum to this article is available at .  相似文献   
89.
BACKGROUND: Few studies have examined the effect on patients and staff of the physical environment in primary care facilities. AIM: To explore changes in patient and staff satisfaction, patient anxiety, and patient-doctor communication when a GP surgery moves from old premises to enhanced purpose-built accommodation. DESIGN OF STUDY: Questionnaire surveys, interviews, and focus groups pre- and post move. SETTING: An urban general practice in Bristol. METHOD: Patient questionnaires assessed anxiety (Spielberger State-Trait Anxiety Inventory; STAI), satisfaction with the environment, and communication during the consultation. Staff questionnaires assessed satisfaction with the environment and job satisfaction. Qualitative methods explored patient and staff views in more depth. RESULTS: A total of 1118 pre-move and 954 post-move patient questionnaires showed significant increases in satisfaction scores for reception/waiting areas (mean 6.46, 95% confidence interval [CI]=5.97 to 6.95) and consulting rooms (mean 3.80, 95% CI=3.44 to 4.15) in the new premises. Patients' satisfaction with patient-doctor communication also increased (mean 0.88, 95% CI=0.30 to 1.46) and anxiety scores were significantly reduced before and after the consultation in the new premises compared with the old (STAI mean difference before consultation 0.72, 95% CI=0.37 to 1.08; mean after consultation 0.37, 95% CI=0.03 to 0.72). Patients highlighted the increased space and light, more modern appearance, greater comfort, and novel works of art in the new surgery. Staff workplace satisfaction increased significantly after moving and remained higher than in the old building. CONCLUSION: This large-scale study examining the effects of a UK primary care environment on patients and staff shows that an enhanced environment is associated with improvements in patients' perception of patient-doctor communication, reduction in anxiety, and increases in patient and staff satisfaction.  相似文献   
90.
The paper aims to present the strengths and weaknesses of computational fluid mechanics (CFM) compared with existing in vitro haemodynamic techniques such as LDA, hot-wire anemometry and static pressure measurement, and to discuss the application of CFM to the analysis of prosthetic heart valve flow. It presents a brief summary of existing methods used in analysing in vitro heart valve flow (along with CFM), the special problems inherent in each method and the quantities each is capable of giving. The analysis then goes on to present examples of information yielded by CFM. It also contains a brief discussion of the data requirements for the analysis of heart valve performance and the clinical relevance of fluid dynamic occurrences. The conclusion drawn is that CFM has a major role to play in the analysis of prosthetic heart valve flow and design because of the improved availability of data afforded and the increased correlation between CFM and clinical flow regimes, due to the ability to consider realistic models of blood.  相似文献   
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