Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Knowledge Sources”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,279 records · Page 71Linked to original sources
PubMed2004

Pork meat: a good source of selenium?

The knowledge about Se bioavailability from animal food is sparse. This study was therefore initiated in order to evaluate the bioavailability of Se from pork meat in humans. Twelve male volunteers (age 21-30 years) participated in a randomised crossover study with strictly controlled diet containing 170 g pig meat/10 MJ per day and 106 +/- 13 microg Se/d for 3 x 3 weeks. Complete faecal and urinary collections were made during the last week of each period. Bioavailability was evaluated from absorption and retention of Se and changes in plasma Se concentration and blood glutathione peroxidase (GSHPx) activity. The apparent absorption of Se was 94 +/- 2% (100 +/- 13 microg/d). Faecal and urinary excretion were 7 +/- 1 microg/d and 39 +/- 21 microg/d, respectively, resulting in a retention of 61 +/- 24 microg/d. The diet intervention did not affect plasma Se concentration and GSHPx activity. Absorption and retention of Se from pig meat were high suggesting a high availability. However, the availability of pig meat Se for blood Se protein appears to be low.

Adult↗
PubMed1997

Tacit integration and referential structure in the language comprehension of aphasics and normals.

Aphasics, brain-damaged patients with no language deficit, neurologically intact elderly subjects, and university undergraduates matched pictures to sentences having compelling tacit implications (e.g., the sentence The fox grabs the hen strongly invites one to assume that the fox will eat the hen). All groups made, for the same sentences, qualitatively similar referential errors consisting in choosing a tacit implication picture. Two auxiliary experiments using the same target sentences in other interpretive situations permitted ruling out the possibility that these errors were due to the putative intrinsic semantic properties of the sentences, showing that the sentences which were most liable to elicit integrative error varied from task to task. These results are interpreted within the conceptual framework which posits that reliable directions for interpretation are couched by the speaker in the very structure of his utterances (the utterance's referential structure) providing the hearer with means to restructure the relevant personal knowledge integrated into the interpretive process in accordance with the speaker's communicative intent. The determination of the referential structure (RSD) of utterances thus seems critical to their correct or, more precisely, conventional interpretation, and, along with the tacit integration of relevant sources of personal knowledge, constitutes the principal cognitive device enabling us to understand each other. But this device appears to be easily corruptible. It is suggested that many errors made by aphasics in language interpretation are due to a failure to follow all referential instructions, but that qualitatively similar failures also occur in normal subjects, though to a lessen degree. Language interpretation is a fallible process and aphasic errors provide remarkable clues for the understanding of its subtle referential mechanisms.

Adult↗
PubMed2005

The isolated perfused kidney: an in vitro test system for evaluation of renal tissue damage induced by high-energy shockwaves sources.

Most of our knowledge of shockwave-induced renal damage is based on animal experiments and clinical observation. We developed a tissue model using isolated porcine kidneys perfused with Berliner Blau dye in physiologic saline using a Ureteromat Perez-Castro peristaltic pump connected to the renal artery. Reproducible results were obtained under a variety of experimental conditions. Further refinements of the model might consist of interposition of tissue layers in the shockwave path or simulation of ventilatory movements.

Animals↗
PubMed1987

Yoghurt: an unlikely source of Campylobacter jejuni/coli.

Knowledge of the relative insensitivity of Campylobacter jejuni to moderately acid environments prompted us to study its survival in different batches of yoghurt of pH range 4.2-5.3 and the role of organic or inorganic acid in the die-off of this pathogen. None of the 11 strains of C. jejuni or C. coli survived more than 25 min in yoghurt. Suspecting that this rapid die-off cannot be accounted for by the pH of the yoghurt we compared the survival rates of C. jejuni in milk, whose pH had been adjusted by lactic, propionic and hydrochloric acid respectively, with that of yoghurt. Even for an inoculum of 10(5)-10(8) cfu/ml propionic acid was bactericidal in minutes. Lactic acid reduced the bacterial populations by 3-5 logs in 30 min. Strong inorganic acid HCl, by contrast, had little or no effect on the populations. Although lactic acid is quite bactericidal for C. jejuni, it is apparently not the only factor to which the prompt elimination of this pathogen from yoghurt could be attributed.

Animals↗
PubMed2006

Biological monitoring of polyfluoroalkyl substances: A review.

Polyfluoroalkyl substances (PFSs) are used in industrial and commercial products and can degrade to persistent perfluorocarboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs). Temporal trend studies using human, fish, bird, and marine mammal samples indicate that exposure to PFSs has increased significantly over the past 15-25 years. This review summarizes the biological monitoring of PFCAs, PFSAs, and related PFSs in wildlife and humans, compares concentrations and contamination profiles among species and locations, evaluatesthe bioaccumulation/biomagnification in the environment, discusses possible sources, and identifies knowledge gaps. PFSs can reach elevated concentrations in humans and wildlife inhabiting industrialized areas of North America, Europe, and Asia (2-30,000 ng/ mL or ng/g of wet weight (ww)). PFSs have also been detected in organisms from the Arctic and mid-ocean islands (< or = 3000 ng/g ww). In humans, PFSAs and PFCAs have been shown to vary among ethnic groups and PFCA/PFSA profiles differ from those in wildlife with high proportions of perfluorooctanoic acid and perfluorooctane sulfonate. The pattern of contamination in wildlife varied among species and locations suggesting multiple emission sources. Food web analyses have shown that PFCAs and PFSAs can bioaccumulate and biomagnify in marine and freshwater ecosystems. Knowledge gaps with respect to the transport, accumulation, biodegradation, temporal/spatial trends and PFS precursors have been identified. Continuous monitoring with key sentinel species and standardization of analytical methods are recommended.

Alkanesulfonic Acids↗
PubMed2006

What are the sources of exposure to eight frequently used phthalic acid esters in Europeans?

Phthalic acid esters (phthalates) are used as plasticizers in numerous consumer products, commodities, and building materials. Consequently, phthalates are found in human residential and occupational environments in high concentrations, both in air and in dust. Phthalates are also ubiquitous food and environmental contaminants. An increasing number of studies sampling human urine reveal the ubiquitous phthalate exposure of consumers in industrialized countries. At the same time, recent toxicological studies have demonstrated the potential of the most important phthalates to disturb the human hormonal system and human sexual development and reproduction. Additionally, phthalates are suspected to trigger asthma and dermal diseases in children. To find the important sources of phthalates in Europeans, a scenario-based approach is applied here. Scenarios representing realistic exposure situations are generated to calculate the age-specific range in daily consumer exposure to eight phthalates. The scenarios demonstrate that exposure of infant and adult consumers is caused by different sources in many cases. Infant consumers experience significantly higher daily exposure to phthalates in relation to their body weight than older consumers. The use of consumer products and different indoor sources dominate the exposure to dimethyl, diethyl, benzylbutyl, diisononyl, and diisodecyl phthalates, whereas food has a major influence on the exposure to diisobutyl, dibutyl, and di-2-ethylhexyl phthalates. The scenario-based approach chosen in the present study provides a link between the knowledge on emission sources of phthalates and the concentrations of phthalate metabolites found in human urine.

Adolescent↗
PubMed1997

[Sources of information and their relationship to the degree of knowledge about AIDS in Mexican adolescents].

INTRODUCTION: In Mexico 2.1% of the cases of AIDS are in adolescents. The cases of AIDS in the age group of 20 to 29 account for 30.5% of all the cases and an important proportion could have been infected with HIV in their adolescence, in view of the length of the incubation period from the infection with HIV to the manifestation of the syndrome. The adolescent's knowledge of HIV/AIDS varies. In some urban contexts the adolescents have lay concepts and myths that could guide them into misting practices that could lead to contamination by HIV. The mass media, especially television, and interpersonal sources such as teachers, parents and peers are important sources of information about HIV/AIDS and have a central role in the social construction and public perception of the problem in adolescents. The objective of the study is to relate the degree of knowledge of HIV/AIDS to the exposure to information sources among adolescents in Guadalajara city, in Mexico. MATERIAL AND METHOD: Survey sample with autoapplied questionnaire. Sample of 1,410 adolescents, male and female, of 15 to 19 years of age, in the four socioeconomic strata. The Chi-square and BTukey tests, 95% confidence interval for proportions and means, and simple ANOVA factor were applied. RESULTS: A considerate degree of knowledge (mean of 13.94 correct answer out of 24, standard deviation = 4.09, 95% CI = 13.69-14.11) was found significant mean differences in favor of the high (15.70) and medium (14.26) strata as opposed to the low (13.51) and marginalized (12.85) (F = 19.39, p < .0001, BTukey level .050). The information published by the newspapers (F = 11.1; p < .001) and the teachers (F = 3.72; p < .05) had a direct relationship to the degree of knowledge imported by the daily exposure to the television and other social demographic variables. CONCLUSIONS: The results describe the presence of inequalities by socioeconomic strata in the list of sources in information and the levels of knowledge about HIV/AIDS. It is necessary to strengthen and develop educational action and the publication of messages through the media, institutions and interpersonal networks, with emphasis on interpersonal and media sources available to the low and marginalized strata, and at the same time, to strengthen the action of sources of information available to the other socioeconomic strata.

Acquired Immunodeficiency Syndrome↗
PubMed2006

A survey of herbal and alternative medication use among participants with eating disorder symptoms.

OBJECTIVE: The purpose of this survey was to collect data on herbal use in participants with eating disorder symptoms. METHOD: A survey was administered to 100 participants who had either sought treatment at the Eating Disorder Institute (EDI) or had been enrolled in previous research as the result of eating disorder symptoms. RESULTS: Of the 100 participants, 64% used an herbal product for weight loss. The mean monthly expenditure on herbs over the past year was 33.88 dollars +/- 41.10 dollars, with a range of 2 dollars-200 dollars. Dexatrim (Chattem, Chattanooga, TN; N = 27) and St. John's Wort (N = 19) had the highest reported use. Magazines were the most common source of product information (38.3%), with health care professionals being reported less frequently as the source of information. Knowledge of ephedra-related adverse effects was variable, and depended on a previous history of use. The majority (62.3%) of herb users reported an adverse effect. CONCLUSION: Herbal use is frequent among those with eating disorder symptoms, often resulting in substantial financial cost. Health professionals are rarely the source of herbal information. Therefore, there is ample room for educational interventions, which may result in the safer use of herbal products.

Adult↗
PubMed1995

A knowledge-based care protocol system for ICU.

There is a growing interest in using care maps in ICU. So far, the emphasis has been on developing the critical path, problem/outcome, and variance reporting for specific diagnoses. This paper presents a conceptual knowledge-based care protocol system design for the ICU. It is based on the manual care map currently in use for managing myocardial infarction in the ICU of the Sturgeon General Hospital in Alberta. The proposed design uses expert rules, object schemas, case-based reasoning, and quantitative models as sources of its knowledge. Also being developed is a decision model with explicit linkages for outcome-process-measure from the care map. The resulting system is intended as a bedside charting and decision-support tool for caregivers. Proposed usage includes charting by acknowledgment, generation of alerts, and critiques on variances/events recorded, recommendations for planned interventions, and comparison with historical cases. Currently, a prototype is being developed on a PC-based network with Visual Basic, Level-Expert Object, and xBase. A clinical trial is also planned to evaluate whether this knowledge-based care protocol can reduce the length of stay of patients with myocardial infarction in the ICU.

Alberta↗
PubMed1993

Singapore dentists' knowledge, advocacy and utilisation of mouthguards.

A questionnaire was distributed to Singapore Registered Dental Practitioners, seeking demographic details, knowledge of mouthguards in preventing dental injury during contact sport, current attitudes to advice and provision to at-risk patients. 636 questionnaires were posted and 226 valid replies were received. Most dentists believed that mouthguards reduced the prevalence of dental injury in contact sports. Undergraduate education was the primary source of dentists' knowledge. Seventy-four per cent of respondents actively recommended mouthguards, but only 26 per cent made one or more in 1992. Only 3 dentists made more than 10. Twenty-eight per cent were comfortable with their knowledge in this area, and 76 per cent would be willing to assist a public awareness campaign.

Athletic Injuries↗
PubMed1993

Information needs on emergency contraception not being met.

During the 1980s, there was 2 prominent changes in family planning: more women went to general practitioners (GPs) for contraceptive advice and there was an upturn in the use of condoms due to safer sex campaigns in the mid-80s. In this study of 769 women requesting a pregnancy termination, the author's found that the greater use of condoms had appeared to increase the need for information about emergency contraception, but this was not being met. Patients advised by their GPs seemed to have a lower level of knowledge than those who obtained their contraception from clinics. The study, carried out at St. James's University Hospital in 1991-92, is compared with several studies in the 1970s and 80s which look at contraceptive usage by women with unwanted pregnancies. Differences were found between those receiving contraceptive advice from different sources (i.e. GPs, clinics, no medical source). Failure of the pill was more frequent in the GP-advised group, but failure of the diaphragm was more frequent in the clinic-advised group. Failure of non-use of condoms did not differ according to the source of advice. Knowledge of and use of emergency contraception was low. Only 14.5% of those using no contraception or recognizing a condom failure attempted to use a secondary or emergency method. Condoms should be used as well as rather than instead of other methods of contraception, and knowledge and availability of emergency contraception should be increased and promoted, recommend the authors. They concluded that problems arising from family planning provision by untrained and uncommitted doctors should be addressed urgently. (Bromham and Cartmill, British Journal of Family Planning, vol. 19, 1993, pp179-183). Commenting on the study findings, FPA Medical Information Office Jane Urwin said: "This study has furthered our knowledge in this area. It also highlights the need for further study of risk-taking behavior in relation to contraceptive use's.

Ambulatory Care Facilities↗
PubMed1999

Estimation of the depth-dependent component of the point spread function of SPECT.

The point spread function (PSF) of a gamma camera describes the photon count density distribution at the detector surface when a point source is imaged. Knowledge of the PSF is important for computer simulation and accurate image reconstruction of single photon emission computed tomography (SPECT) images. To reduce the number of measurements required for PSF characterization and the amount of computer memory to store PSF tables, and to enable generalization of the PSF to different collimator-to-source distances, the PSF may be modeled as the two-dimensional (2D) convolution of the depth-dependent component which is free of detector blurring (PSF(ideal)) and the distance-dependent detector response. Owing to limitations imposed by the radioactive strength of point sources, extended sources have to be used for measurements. Therefore, if PSF(ideal) is estimated from measured responses, corrections have to be made for both the detector blurring and for the extent of the source. In this paper, an approach based on maximum likelihood expectation-maximization (ML-EM) is used to estimate PSF(ideal). In addition, a practical measurement procedure which avoids problems associated with commonly used line-source measurements is proposed. To decrease noise and to prevent nonphysical solutions, shape constraints are applied during the estimation of PSF(ideal). The estimates are generalized to depths other than those which have been measured and are incorporated in a SPECT simulator. The method is validated for Tc-99m and T1-201 by means of measurements on physical phantoms. The corrected responses have the desired shapes and simulated responses closely resemble measured responses. The proposed methodology may, consequently, serve as a basis for accurate three-dimensional (3D) SPECT reconstruction.

Algorithms↗
PubMed1996

[A study on AIDS-related knowledge, attitude and behavior in servicemen in China].

AIDS-related knowledge, attitude and behavior were studied in 1,058 servicemen in China with self-administered and anonymous questionnaires. Results showed 76.7% to 89.5% of the servicemen surveyed knew correctly the risk of AIDS and its route of transmission, but only 8.5% of them answered all the questions listed in the questionnaire correctly. Source of their knowledge about AIDS was mainly from newspapers, magazines and extracurricular books. Most of them thought they could have very little, or no chance to contract the illness. There were 74.0% of the servicemen eager to get knowledge about AIDS and 83.2% would like to accept relevant testing. And, 80.2% of them answered that they could put their behavior under control, or change their unhealthy one to prevent from the illness. It indicated that comprehensive and correct publicity and education could play an active role in the prevention of HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Teaching health and safety: problems and possibilities for learner-centered training.

The University of Massachusetts at Lowell Work Environment Department, working jointly with four New England coalitions on occupational safety and health (COSH) groups, has developed and is delivering participatory and learner-centered health and safety training for hazardous waste site workers and emergency responders throughout New England. This consortium has created a technical curriculum for hazardous waste workers accessible to the nonspecialist and which, more importantly, draws upon workers' own experience and knowledge as a source of information, education, and experiential resources. In this article, we examine the goals of the consortium, the applicability of the training method, its successes and failures, and the wider implications such pedagogical techniques have for effective and empowering health and safety training. We conclude that such a teaching technique is a successful means of providing technical knowledge and skills in a positive and rewarding atmosphere. We also conclude, however, that the extent to which this form of education is empowering, as is claimed by many of its proponents, is less clear-cut.

Curriculum↗
PubMed1988

The role of linguistic and visual information in spelling: a developmental study.

This study investigated the processes that elementary school children use for spelling. Good and poor spellers in grades 3 through 6 spelled words and nonwords that differed in the types of information (phonological, orthographic, morphological, or visual) that could be used to produce their correct spelling. A multiple choice spelling recognition task was also administered. Error rates on words and nonwords were related to the type of information that could be used to determine the correct spelling. Words that could be spelled on the basis of linguistic information were easier than words that could be spelled only on the basis of visual information. While children were sensitive to the linguistic properties of the stimuli, their use and knowledge of various sources of linguistic information was not uniformly developed. Children had the most difficulty with spellings based on morphological information and the least difficulty with those based on invariant sound-spelling relationships. On the dictation and the nonword tasks, younger children and poorer spellers differed from older children and better spellers in the overall level of their knowledge, but all children showed a similar pattern of results suggesting that they did not use different processes to spell words. However, the data from the recognition task suggested that poor spellers may rely more on visual information than good spellers.

Achievement↗
PubMed1981

Knowledge and use of "alternative" cancer therapies in children.

Because of the increased interest in laetrile and other "alternative" cancer therapies among cancer patients and the lack of data concerning knowledge and use of such treatments in childhood cancer, parents of children diagnosed with cancer in 1977 and 1978 at a major pediatric oncology center were surveyed. Eight different "alternative" therapies or groups were known by 50% of parents. Seventeen of 106 children had received an "alternative" cancer treatment. News media were the most frequent initial information source. Accuracy of knowledge of toxic effects of laetrile was poor, with only 26.4% realizing poisoning was possible. Parents who felt desperation in their search for a cure and were looking for an easier treatment method, and those who were dissatisfied with their role in making treatment decisions, appeared at greatest risk of seeking "alternative" therapies. Over 56% of parents wanted more information about cancer and its treatment, with written information favored by almost 40%.

Adolescent↗
PubMed2003

Condom use and the accuracy of AIDS knowledge in Côte d'Ivoire.

CONTEXT: Condom use remains low in Côte d'Ivoire, despite an increasing prevalence of HIV and widespread awareness of how the virus is transmitted. Information is needed about characteristics that predict condom use and about the role of AIDS knowledge and sex differences in the use of condoms. METHODS: Data from the 1994 Côte d'Ivoire Demographic and Health Survey were analyzed for respondents who had had sex in the two months before the survey. Logistic regressions were performed separately by sex to determine whether the accuracy of men's and women's knowledge about AIDS predicted condom use at their most recent sexual intercourse. RESULTS: Accuracy of knowledge about AIDS did not significantly predict condom use. For male respondents, the odds of condom use at last intercourse were significantly lower among those aged 35 or older than among those aged 15-19 (odds ratios, 0.3-0.5). The odds were also lower among married men (0.4) and those who reported friends, family or neighbors as their only source of AIDS knowledge (0.5). Compared with uneducated men, men with secondary or higher education were significantly more likely to report condom use (1.7). Among women, those aged 25 or older had significantly lower odds of condom use at last intercourse than those aged 15-19 (0.2-0.6). The odds of use were significantly reduced among women who were married (0.2) and those who had learned about AIDS from family, friends or neighbors or from television or radio (0.3-0.6); however, the odds were significantly higher for women with secondary or higher education than for uneducated women (2.2). CONCLUSION: The level of accuracy of AIDS knowledge did not predict the likelihood of recent condom use in this sample. Efforts to increase educational attainment in Côte d'Ivoire may be more effective in increasing condom use than a focus on improving the accuracy of AIDS knowledge.

Acquired Immunodeficiency Syndrome↗