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991.
There is a general consensus that melatonin possesses time-dependent hypnotic effects, but there is no information yet whether it has residual effects on neurobehavioral performance, especially after daytime administration. In the present study we investigated the possible residual effects of 3 mg melatonin on performance relevant to flight and on subjective feelings of sleepiness, arousal, activation and affect after a daytime nap, as a function of nap length. Fifteen reserve pilots of the Israeli Air Force participated in the study. The experiment consisted of four sessions during which either melatonin or placebo was administered at 16:00 h. In two conditions, subjects were allowed to sleep for 2 h (17:00-19:00 h) whereas in the other two only a 0.5-h nap was allowed. After the naps they started performing a flight simulator task every 2 h. Sleep efficiency significantly increased and sleep latency significantly decreased in both melatonin conditions compared to placebo. Flight performance was only mildly affected in the 0.5-h nap condition. Subjective assessment of sleepiness significantly differed between the two treatment conditions, only in the 0.5-h nap condition. Subjects felt sleepier 2-4 h after melatonin administration. To conclude, our data suggest that administration of melatonin before a brief daytime nap (about 0.5 h) may be associated with mild residual effects on psychomotor performance and may significantly affect subjective feeling of sleepiness for 2-4 h.  相似文献   
992.
993.
PURPOSE: This article proposes a model grounded in behavioral theory and empirical evidence for use when developing a program to prevent type 2 diabetes in high-risk minority youth. METHODS: The model is based on key concepts of 4 behavioral theories: the Health Belief Model, Social Learning Theory, the Theory of Planned Behavior, and the Ecological Model. Determinants of behavior to target for change are selected based on their theoretical link to behavior change, their success in changing behavior in past programs, and through thorough formative research in the target community. RESULTS: Diabetes prevention in children requires modifying a complex set of behavior patterns. Social norms and the environment are especially important in children in whom cognitive processes have not fully developed. Family and community involvement is essential for developing a health program and providing a supportive environment in which to change behavior and ongoing reinforcement to maintain behavior changes. CONCLUSIONS: Behavioral theory informs the selection of factors to target in a behavioral intervention. Special considerations apply when working with children. A program to target risk must be based in behavioral theory, supported by practical data, and tailored to the needs and beliefs of the target community.  相似文献   
994.
Reacting to a pandemic influenza outbreak will require the mass distribution of vaccine, when available, which will require county health departments to set up and operate one or more mass vaccination clinics, also known as points of dispensing (PODs). Carefully planning these PODs before an event occurs is a difficult but important job. First, this article describes a tool--the Clinic Planning Model Generator computer program--designed to help public health agencies evaluate and make adjustments to their POD plans. The Clinic Planning Model Generator was built on data from a smallpox exercise and other biological agent POD exercises. Second, this article demonstrates the application of the Clinic Planning Model Generator through an example pandemic influenza scenario. This work is the result of an ongoing collaboration between Montgomery County, Maryland's Advanced Practice Center for Public Health Emergency Preparedness and Response, and the Institute for Systems Research at the University of Maryland.  相似文献   
995.
Objective To describe the use of a multifaceted strategy for recruiting general practitioners (GPs) and community pharmacists to talk about medication errors which have resulted in preventable drug‐related admissions to hospital. This is a potentially sensitive subject with medicolegal implications. Setting Four primary care trusts and one teaching hospital in the UK. Method Letters were mailed to community pharmacists and general practitioners asking for provisional consent to be interviewed and permission to contact them again should a patient be admitted to hospital as a result of a medication error. In addition, GPs were asked for permission to approach their patients should they be admitted to hospital. A multifaceted approach to recruitment was used including gaining support for the study from professional defence agencies and local champions. Key findings Eighty‐five percent (310/385) of GPs and 62% (93/149) of community pharmacists responded to the letters. Eighty‐five percent (266/310) of GPs who responded and 81% (75/93) of community pharmacists who responded gave provisional consent to participate in interviews. All GPs (14 out of 14) and community pharmacists (10 out of 10) who were subsequently asked to participate, when patients were admitted to hospital, agreed to be interviewed. Conclusion The multifaceted approach to recruitment was associated with an impressive response when asking healthcare professionals to be interviewed about medication errors which have resulted in preventable drug‐related morbidity.  相似文献   
996.
997.
Objectives:  An increased understanding of the reasons for noncompliance and lack of persistence with prescribed medication is an important step to improve treatment effectiveness, and thus patient health. Explanations have been attempted from epidemiological, sociological, and psychological perspectives. Economic models (utility maximization, time preferences, health capital, bilateral bargaining, stated preference, and prospect theory) may contribute to the understanding of medication-taking behavior.
Methods:  Economic models are applied to medication noncompliance. Traditional consumer choice models under a budget constraint do apply to medication-taking behavior in that increased prices cause decreased utilization. Nevertheless, empiric evidence suggests that budget constraints are not the only factor affecting consumer choice around medicines. Examination of time preference models suggests that the intuitive association between time preference and medication compliance has not been investigated extensively, and has not been proven empirically. The health capital model has theoretical relevance, but has not been applied to compliance. Bilateral bargaining may present an alternative model to concordance of the patient–prescriber relationship, taking account of game-playing by either party. Nevertheless, there is limited empiric evidence to test its usefulness. Stated preference methods have been applied most extensively to medicines use.
Results:  Evidence suggests that patients' preferences are consistently affected by side effects, and that preferences change over time, with age and experience. Prospect theory attempts to explain how new information changes risk perceptions and associated behavior but has not been applied empirically to medication use.
Conclusions:  Economic models of behavior may contribute to the understanding of medication use, but more empiric work is needed to assess their applicability.  相似文献   
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999.
1000.
Steroid hormone activity of flavonoids and related compounds   总被引:12,自引:0,他引:12  
Soy isoflavones have been studied extensively for estrogenic and antiestrogenic properties. Other flavonoids, found in fruits, vegetables, tea and wine, have been much less tested for steroid hormone activity. We therefore assessed the estrogenic, androgenic and progestational activities of 72 flavonoids and structurally-related compounds. These compounds were tested on BT-474 human breast cancer cells at concentrations of 108–10–5M, with estradiol (estrogen), norgestrel (progestin) and dihydrotestosterone (androgen) used as positive controls, and ethanol (solvent) as a negative control. pS2, an estrogen-regulated protein, and prostate-specific antigen (PSA), regulated by androgens and progestins, were quantified in tissue culture supernatants using ELISA-type immunofluorometric assays developed in-house. Of the 72 compounds tested, 18 showed estrogenic activity at 10–5M. Of this subset, seven also showed progestational activity at this concentration. The soy isoflavones, biochanin A and genistein, showed the most potent estrogenic activity, with a dose-response effect up to 10–7 M. Of all other flavonoids, luteolin and naringenin displayed the strongest estrogenicity, while apigenin had a relatively strong progestational activity. Based on our data, we have formulated a set of structure/function relationships between the tested compounds. Flavonoids, therefore, exhibit significant steroid hormone activity, and may have an effect in the modification of cancer risk by diet, or in cancer therapeutics and prevention.  相似文献   
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