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ObjectiveTo describe the use of the Internet by primary care patients to seek health related information, understand how they are influenced by this information, and evaluate its impact on the doctor-patient relationship.DesignCross sectional study, through self-administered survey.SettingOne urban health center in Madrid.ParticipantsA total of 323 questionnaires were collected from patients between 14 and 75 years old who attended a physician's office for any reason, excluding illiterate patients and those with neurological or psychiatric problems preventing them from completing the survey.MeasurementsInternet usage, ability of the internet to clarify doubts regarding health issues, patient lifestyle changes, socio-demographic variables, and physician's receptivity to the use of internet by patients.Results61% (CI 95%: 56%-67%) of patients used the Internet as a source of health information: Internet queries were able to address health doubts in 92.4% of users, 53.5% reported that the Internet changed their thinking about their health in at least one instance, 30% made behavioral changes (of which 60.1% discussed these changes with their physician), 44.3% had more questions at the physician's office, and 80.8% believe that the doctor would be willing to talk about the information found on the internet.ConclusionsUsing the Internet to find information about health is very common, with positive influence on physician-patient relationship. This may be useful for achieving behavioral changes in patients and can be used as a tool in medical practice.  相似文献   
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Orange juice (OJ) is among the most consumed fruit juices worldwide, and its chemopreventive action is fairly addressed in the literature. This review critically presents the available evidence linking OJ with cancer chemoprevention and on discussing the putative mechanisms and negative health effects. The chemopreventive action of OJ is related to its effect on metabolic enzymes and its antiinflammatory, cytoprotective/apoptotic, hormonal, cell signaling-modulating, antioxidant, and antigenotoxic effects. Most studies on OJ are in vitro, and few are conducted in vivo. Results from in vitro studies must be interpreted carefully because these findings do not consider in vivo bioavailability. However, such results are useful for studying the impact of different processing and storage methods on OJ's chemopreventive effect. Evidence of OJ's chemoprevention in humans is limited. OJ is antimutagenic in bacteria and antigenotoxic in humans and rodents. Studies using rodent cancer models showed that OJ is cancer chemopreventive, influencing either the induction stage or the promotion stage. The composition and, therefore, the chemopreventive action of OJ might be influenced by different cultivars, climates, extraction methods, packaging, storage temperatures, and shelf lives, among other factors. Epidemiological studies and randomized controlled intervention studies in humans evaluating the chemopreventive effect of OJ, taking into consideration variability in OJ composition, are needed.  相似文献   
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ABSTRACT

Introduction: In 1993, the Food and Drug Administration (FDA) published a guideline for the study and evaluation of gender-related differences in clinical trials. However, the extent of the implementation of these recommendations has not been systematically reviewed.

Objectives: To determine the proportion of women in clinical trials of Aripiprazole, a new atypical antipsychotic, and to analyze the resulting information on a gender-specific basis.

Method: A systematic review was conducted in Medline to identify randomized trials that compared this new antipsychotic drug with placebo or with typical or atypical antipsychotics in patients diagnosed with schizophrenia. The FDA Guideline was followed for the study and evaluation of gender-specific results of clinical trials.

Results: Despite the inclusion of female participants in the samples studied, the failure to conduct analyses stratified by sex prevented us from ascertaining the possible differences between men and women in the therapeutic response or in the adverse side effects of treatment with Aripiprazole.  相似文献   
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? Teeth were collected from populations differing in their degree of industrialization and from prehistoric populations. Lead analysis of dentine revealed that in contemporary teeth the lead level was related to the degree of industrialization and that in prehistoric teeth very low concentrations of lead were present. Because tooth lead reflects the body burden of lead this result suggested that the prehistoric populations and modern nonindustrial populations were exposed to environments low in lead. Teeth from a contemporary population of nonindustrialized Indians of the Lacandon forest in Mexico contain lead in concentrations comparable with those of the prehistoric populations. Comparison of the Indian teeth with teeth from a modern industrial population reveals a 45-fold difference in median tooth lead level. This finding lends support to the hypothesis that high levels of urban lead pollution result in elevated body burdens of lead.  相似文献   
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Acanthamoeba is an opportunistic pathogen in humans, whose infections most commonly manifest as Acanthamoeba keratitis or, more rarely, granulomatous amoebic encephalitis. Although there are many therapeutic options for the treatment of Acanthamoeba, they are generally lengthy and/or have limited efficacy. Therefore, there is a requirement for the identification, validation, and development of novel therapeutic targets against these pathogens. Recently, RNA interference (RNAi) has been widely used for these validation purposes and has proven to be a powerful tool for Acanthamoeba therapeutics. Ergosterol is one of the major sterols in the membrane of Acanthamoeba. 3-Hydroxy-3-methylglutaryl–coenzyme A (HMG-CoA) reductase is an enzyme that catalyzes the conversion of HMG-CoA to mevalonate, one of the precursors for the production of cholesterol in humans and ergosterol in plants, fungi, and protozoa. Statins are compounds which inhibit this enzyme and so are promising as chemotherapeutics. In order to validate whether this enzyme could be an interesting therapeutic target in Acanthamoeba, small interfering RNAs (siRNAs) against HMG-CoA were developed and used to evaluate the effects induced by the inhibition of Acanthamoeba HMG-CoA. It was found that HMG-CoA is a potential drug target in these pathogenic free-living amoebae, and various statins were evaluated in vitro against three clinical strains of Acanthamoeba by using a colorimetric assay, showing important activities against the tested strains. We conclude that the targeting of HMG-CoA and Acanthamoeba treatment using statins is a novel powerful treatment option against Acanthamoeba species in human disease.  相似文献   
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