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21.
Dr M. Weeke-Lüttmann 《European journal of epidemiology》1994,10(4):513-514
The epidemiological situation calls for almost yearly changes in the antigenic composition of influenza vaccine, thus necessitating fresh licensing procedures. Since the time for bringing a new vaccine onto the market should be relatively short, the following work of all parties involved must be done expeditiously: 1) WHO recommendations on new virus strains and their subsequent adaptation by the EEC (February/March); 2) Distribution of the new virus strains to the International Reference Centers for Influenza in the UK and USA (February/ March); the centers later issue reference materials for the determination of the haemagglutinin antigen concentration (April/May); 3) Production and testing of seed virus by manufacturers, as well as validation of the producer's inactivation process for the new virus strains (May/June); 4) Licensing of the vaccines by the National Control Authority (Paul-Ehrlich-Institute) (June/July); in the case of previously licensed products, the procedure is limited essentially to the approval of the detailed protocol of production and tests on the new virus strains, clinical studies not being required before licensing because of a lack of time; 5) Paul-Ehrlich-Institute's test for batch release, according to Directive 89/342/EEC, besides protocol approval, conducts material testing of the endotoxin and antigen content of each vaccine lot; the assay for the antigen quantification is especially laborious and sometimes must be repeated because of test invalidity. 相似文献
22.
23.
Abstract Daan's two process model is known to be one of the most powerful models, covering various situations from free-running to sleep deprivation. In this study, bifurcation properties of the model dynamics as function of a gap, D , between the threshold processes are clarified using a circle map. As a function of D , we will show that the model has the different types of the mutual entrainment regions that are intervened by the tangent bifurcation. The variable behavior of human circadian rhythm is suggested to be systematically understood based on the bifurcation properties of the two process model. 相似文献
24.
A microcapsule form of nitrofurantoin was prepared by a simple coacervation method with carboxymethylcellulose and aluminium sulfate. 33 factorial design was performed for three independent variables, namely, the particle size of the drug, the size of the microcapsules and the pH of the dissolution medium. The dissolution tests with the formulated microcapsules were carried out according to the United States Pharmacopeia XXII rotating basket method at pH 1.2, 5 and 7.5, which represent the pH of gastrointestinal fluids. Release data were examined kinetically and the ideal kinetic models were estimated and t
63.2 values obtained from RRSBW distribution were used in the factorial design experiment. The influence of the independent variables on the dissolution of nitrofurantoin microcapsules could be expressed as the pH of the dissolution medium > particle size of the microcapsule > particle size of nitrofurantoin. The other aim of this study was to evaluate microcapsule formulation in terms of the United States Pharmacopeia criteria with a minimum of experiments. Our findings suggest that dosage forms which comply with the pharmacopoeia criteria for dissolution can be prepared and selected by factorial design. 相似文献
25.
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
26.
Ann Netten 《International journal of geriatric psychiatry》1989,4(3):143-153
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.
27.
Potent inhibition of HIV-1 entry by (s4dU)35 总被引:2,自引:0,他引:2
Horváth A Tokés S Hartman T Watson K Turpin JA Buckheit RW Sebestyén Z Szöllosi J Benko I Bardos TJ Dunn JA Fésüs L Tóth FD Aradi J 《Virology》2005,334(2):214-223
28.
Koorengevel KM Beersma DG Den Boer JA Van Den Hoofdakker RH 《Journal of sleep research》2002,11(4):347-356
The majority of winter-type seasonal affective disorder (SAD) patients complain of hypersomnia and daytime drowsiness. As human sleep is regulated by the interaction of circadian, ultradian and homeostatic processes, sleep disturbances may be caused by either one of these factors. The present study focuses on homeostatic and ultradian aspects of sleep regulation in SAD. Sleep was recorded polysomnographically in seven SAD patients and matched controls subjected to a 120-h forced desynchrony protocol. In time isolation, subjects were exposed to six 20-h days, each comprising a 6.5-h period for sleep. Patients participated while being depressed, while remitted after light therapy and in summer. Controls were studied in winter and in summer. In each condition, the data of each subject were averaged across all recordings. Thus, the influence of the effects of the circadian pacemaker on sleep was excluded mathematically. The comparison of patients with controls and with themselves in the various conditions revealed no abnormalities in homeostatic parameters: sleep stage variables, relative power spectra and time courses of power in various frequency bands across the first three non-rapid eye movement-rapid eye movement (NREM-REM) cycles showed no differences. The data suggest that homeostatic processes are not involved in the disturbance of sleep in SAD. 相似文献
29.
We comment on the target article by Weingardt (this issue), which discusses recent advances in instructional design and technology (IDT) and their implications for dissemination of evidence-based practices. These arguments are extended to the topic of psychological intervention design, and possibilities for new intervention structures are briefly explored. Finally, comments are offered on maintaining a careful balance between technological and social processes in the effort to promote the dissemination of innovative and evidence-based psychological procedures. 相似文献
30.
Constrained optimization recently has been implemented in the LISREL software package, allowing formulation of parent-offspring transmission models in a simple and efficient manner. A reverse path model of parental transmission is described within the LISREL framework for application to twin and/or adoptive family data. The model incorporates genetic and environmental parameter constraints arising from assortative mating and cultural transmission. An illustration of the LISREL model is given using measures obtained from twins and parents involving fear of social criticism. 相似文献