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PubMed2002

Return-to-work interventions for low back pain: a descriptive review of contents and concepts of working mechanisms.

Low back pain is a major medical and social problem associated with disability, work absenteeism and high costs. Given the impact of the problem, there is a need for effective treatment interventions in occupational healthcare that aim at the prevention of chronic disability and the realisation of return to work. These so-called return-to-work (RTW) interventions are becoming increasingly popular. As well as questions concerning the effectiveness of RTW interventions, there are also important questions on the actual content and underlying concepts of these multifactorial intervention strategies. The purpose of this review is to examine the literature on the content and underlying concepts of RTW interventions for low back pain. A systematic literature search identified 14 randomised controlled trials (RCTs) evaluating the effects of 19 RTW interventions. The content and concepts of these RTW interventions are described, compared and discussed in this review. Further, the contents of the RTW interventions are classified by the use of predefined components (physical exercises, education, behavioural treatments and ergonomic measures). The identified RTW interventions varied with respect to the disciplines involved, the target population and the number and duration of sessions. The classification showed that physical exercises were a component of most of the selected interventions, followed by education, behavioural treatments and ergonomic measures. The most prevalent combination of components was the combination of physical exercises, behavioural treatment and education. However, the types of physical exercises, behavioural treatment and education varied widely among the RTW interventions. The described concepts for the physical exercises were an increase of muscle strength, coordination, range of motion of the spine and cardiovascular fitness, and a decrease of muscle tension. Education as a part of RTW interventions is believed to increase the understanding of patients regarding their disorder and treatment. Behavioural treatments were mainly based on the gate control theory of pain (psychophysiological processes are involved in pain perception) and/or the operant conditioning hypothesis (pain behaviour is determined by its consequences). No concepts were described for ergonomic measures. Finally, the plausibility of the described concepts is discussed. Future RCTs on this topic should evaluate the underlying concepts of the RTW intervention in addition to its effectiveness.

Absenteeism↗

PubMed2001

Calf removal improves conception rates to the Ovsynch and CO-Synch protocols.

Beef cows (n = 473) from two locations were stratified by breed, postpartum interval, age, and AI sire and were randomly allotted to one of four treatments for synchronization of ovulation. Ovulation synchronization protocols included the Ovsynch protocol with (n = 114) or without (n = 123) 48-h calf removal from d 7 to 9 (d 0 = 1st GnRH injection) or the CO-Synch protocol with (n = 119) or without (n = 117) 48-h calf removal from d 7 to 9. The Ovsynch protocol included administration of GnRH (100 microg; i.m.) on d 0, PGF2alpha (25 mg; i.m.) on d 7, GnRH (100 microg; i.m.) on d 9, and timed insemination on d 10. The CO-Synch protocol included administration of GnRH (100 microg; i.m.) on d 0, PGF2alpha (25 mg; i.m.) on d 7, and GnRH (100 microg; i.m.) with timed insemination on d 9. Blood samples were collected from all cows on d -10 and d 0 for analysis of serum progesterone. Cows with at least one serum progesterone concentration greater than 1 ng/mL were considered to be cyclic at the time of treatment. Conception rates of cows that received the CO-Synch + calf removal, Ovsynch + calf removal, CO-Synch, or Ovsynch protocol (63, 61, 54, and 52%, respectively) were not different (P = 0.50). Conception rates were not different (P = 0.80) among CO-Synch- and Ovsynch-treated cows; however, both estrual status and 48-h calf removal affected conception rates. Conception rates of cyclic cows (66%) were greater (P = 0.01) than those of anestrous cows (53%), regardless of which synchronization protocol was used. When data were pooled across synchronization protocol, conception rates of cows with 48-h calf removal (62%) were greater (P = 0.09) than conception rates of cows without calf removal (53%). The CO-Synch + calf removal protocol induces a fertile ovulation in cyclic and anestrous cows, requires handling cattle just three times, results in high conception rates from timed insemination, and should be a useful program for synchronization of ovulation in beef cows.

Anestrus↗

PubMed2004

Effects of an injectable trace mineral supplement on first-service conception rate of dairy cows.

A total of 825 dairy cows from a commercial dairy farm in central California were used to evaluate effects of one or 2 doses of an injectable trace mineral supplement containing 20 mg/mL of zinc, 20 mg/mL of manganese, 5 mg/mL of selenium, and 10 mg/mL of copper on first-service conception rate. Cows were randomly allocated into treatment or control group to either a single dose (experiment 1) or a double dose (experiment 2) of injected supplement. Allocation was based on days in lactation for experiment 1 and the length of gestation periods for experiment 2. In experiment 1, cows 38 to 45 d in lactation (n = 190) received a single dose of 5 mL of injected supplement. Similar cows were used as controls (n = 227). In experiment 2, cows and pregnant heifers received an initial injection of 5 mL of the mineral supplement from 2 to 3 wk precalving (n = 186). An equal dose was repeated 38 to 45 d in lactation. A similar group of cows and pregnant heifers served as controls for experiment 2 (n = 222). Health and reproductive events postcalving were recorded. In experiment 1, the odds of first-service conception were not significantly different for cows receiving a one-dose regimen of minerals compared with untreated control cows; conception rates were 26.8 and 27.5% for experiment 1 treatment and control groups, respectively. In experiment 1, the odds of first-service conception were significantly lower (odds ratio = 0.66) for cows and heifers given the 2-dose regimen of minerals compared with untreated controls; overall conception rates were 21.5 and 31.5% for experiment 2 treatment and control groups, respectively. In this intensively managed dairy herd, a single dose of injected trace minerals before breeding had no beneficial effects on first-service conception rate. However, dairy cows receiving a dose of trace minerals before calving and another dose before breeding had lower conception at first service.

Animals↗

PubMed1980

Conception rates of Holstein bulls for artificial insemination on a California dairy.

Data of milk production and reproduction were collected from a 2,500-cow dairy in California for measuring conception rates of bulls for artificial insemination. The bulls were placed into groups of low, medium, or high conception rates. Mean conception rates were 38.2%, 55.7%, and 66.1%, range 34% to 70%. To predict the conception-rate group of a bull required 30 services. There were no differences in average number of lactations and days to first service of the cows bred to the three groups of bulls. Cows bred to the bulls with high conception rate produced 667 kg more milk than cows bred to bulls with low conception rate. Cows bred to the low bulls were bred, on the average, in mid-July, whereas cows bred to the other two groups were bred in June and May. The cost to this dairy for using low conception rate bulls was $21,000.

Animals↗

PubMed1985

Associations among milk yield, yield persistency, conception, and culling of Israeli Holstein dairy cattle.

Genetic correlations among Predicted Differences for milk yield corrected for economic value of fat content, annualized yield, yield persistency, conception rate, and culling rate were estimated. Correlations were .43 between yield persistency and annualized yield, .42 between yield persistency and conception rate, and .1 between annualized yield and conception rate. For Predicted Differences for these traits computed separately for each of first three parities, correlations between pairs were highest for annualized yield and lowest for culling rate. Regression coefficients for conception rate from cow insemination records on daily yield preceding insemination and on absolute change of yield during month of insemination were significantly negative for the first three parities. A positive pleiotropic effect for yield, yield persistency, and conception rate was suggested; therefore, progeny testing for yield persistency may improve yield and conception rate. High yields and large changes of yield during month of insemination adversely affected conception rate of cows within herds.

Animals↗

PubMed1985

Systematic environmental, direct, and service sire effects on conception rate in artificially inseminated Holstein cows.

Result of insemination was verified for 329,314 artificial inseminations by 882 service sires to 97,245 Holstein cows in 1,075 herds between May 1970 and December 1983. Estimates of systematic environmental and genetic components of cow and service sire components of conception rate were obtained preliminary to development of a fertility monitoring system. Conception rate was 2.9% higher in stanchion than loose housed herds and 2.3% higher in grade than registered cows. Fall months were superior to winter months, the greatest difference being 6.1% between October and January. Conception rate increased with herd milk production, decreased with both increased cow age, and increased herd size in mature and old cows. Regions and inseminators within regions were highly variable. Conception may be influenced by semen price; however, week day of insemination and duration of semen storage had no effect. Conception rate decreased for semen by bulls 8 yr and older, was lowest for semen harvested in June, but no season of collection effect was detected. No genetic trends for cow and service sire conception rate were found; heritability and repeatability were .08 and .06, respectively. Genetic correlations between cow and service sire conception rate and these components with first lactation production and semen output measures were all near zero. Therefore, the relationship between sire fertility and daughter fertility is near zero.

Animals↗

PubMed2004

Reflective thinking in clinical nursing education: a concept analysis.

Over decades nursing had an interest in clarifying and developing its knowledge base and its conceptual foundation. Reflective thinking has become a popular word in nursing education world wide, but its meaning and effective use remains debatable because of lack of clarity in its meaning (Mackintosh, 1998:553). The researcher engaged in the concept analysis of reflective thinking so as to fully understand its meaning and interpretation, hence the research question to be addressed by this article is: "What is the meaning of reflective thinking in clinical nursing education?" This article seeks to explore and describe the conceptual meaning of reflective thinking in clinical nursing education using the method of concept analysis as outlined by Wilson (1963:23-39) and Gift (1997:75,76). Concept analysis of reflective thinking constitutes the first phase of a study to develop a model to facilitate reflective thinking in clinical nursing education, thus ensuring theoretical validity of the model. An extensive examination of domain specific and various disciplines' literature was explored as part of the concept analysis. A selection of information regarding variations and similarities in the use and interpretation of reflective thinking across clinical nursing education was drawn from computerised data bases. This increased the rigor and the findings of the analysis. Through deductive reasoning and drawing of inferences, attributes were clustered in an attempt to identify the apparent essence of the concept. Three categories and the related connotations emerged as follows: Antecedents (Cognitive and affective thinking skills). Process (The three phases of reflective thinking). Outcome ( New insight and changed perspective). Reflective thinking was considered from the result of concept analysis as a cyclic, interactive constructing mental process to improve practice in a specific context. It is recommended that a model to facilitate reflective thinking in clinical nursing education be developed based on the results of this concept analysis.

Cognition↗

PubMed1991

Meaning ascribed to major professional concepts: a comparison of occupational therapy students and practitioners in the United States and Israel.

A number of concepts related to human performance, such as occupation, purposeful activity, function, work, doing, and play/leisure, are widely used in occupational therapy. Because these concepts are essential to the profession, we seek to understand their meaning. Many theorists in occupational therapy define and attribute different levels of importance to each of these concepts. The present study examines the professional (student vs. practitioner) and universal (American vs. Israeli) meanings of the six concepts named above. Four statistical methods were used: (a) a multivariate analysis of variance, (b) t tests and a sign test to analyze the Osgood semantic differential, and (c) Individual Differences in Multidimensional Scaling (Carroll & Chang, 1970). The results indicate that the American occupational therapists ascribed higher affective meanings than did all of the other groups to the concepts of purposeful activity, function, doing, and work. No difference was found for occupation and hobby, which rated high for all groups. Differences in the dimensions underlying the concepts between American and Israeli subjects suggest a cultural and linguistic influence on the meaning ascribed to the concepts.

Analysis of Variance↗

PubMedDate not supplied

How pregnancy influences renal function in nephropathic type 1 diabetic women depends on their pre-conceptional creatinine clearance.

Pregnancy in type 1 diabetic women with overt nephropathy can lead to a further deterioration in renal function but it is not clear at what level of pre-conceptional GFR the risk for worsening of renal function begins to increase. Therefore we investigated the influence of pregnancy on renal function in 12 women (14 pregnancies) with pre-conceptional macroproteinuria and near-normal creatinine clearance (range 37-93 ml/min/1.73m2). S-creatinine, creatinine clearance (CrCL), HbA1c and blood pressure (BP) were measured before conception, during each trimester (12th and 24th week of gestation and last week before delivery) and three and six months post-partum. In five diabetic women with six pregnancies (group A) there was a physiological increase in CrCl of 36% up until the 24th week of gestation; their pre-conceptional mean CrCl was 80 (range 70-93) ml/min/1.73m2. In seven women with eight pregnancies (group B) CrCl decreased by 16% during the first two trimesters; the mean CrCl before conception was 61 (37-73) ml/min/1.73m2. In the last week before delivery CrCl worsened transiently in three cases in group A and four in group B, due to pre-eclampsia. Three months post-partum the mean CrCl in group A was 78 (70-91) ml/min/1.73m2, approximately the same as before pregnancy. In group B the mean CrCl was 39 (22-68) ml/min/1.73m2 at this same time; this was 36% lower than the pre-conceptional clearance. Mean HbA1c in both groups were approximately the same, but mean BP tended to be higher during pregnancy in group B, especially in the week before delivery (p<0.05). We conclude that in a high percentage of nephropathic diabetic women with significantly low CrCl before conception, renal function worsens during and after pregnancy. Inadequate antihypertensive therapy may contribute to this.

Adult↗

PubMedDate not supplied

[Is a unified concept of species in ornithology possible? (An opinion of a practicing taxonomist)].

An analysis of current publications on species problem reveals the radical discrepancy between the statements of species reality in nature and different number of these "realities" in light of different species concepts. It has been shown, that the only realities are populations, and "species" is only logical construct--the notion. A concept of species is a system of interconnected notions, where the main element--ontology of species has been always given a priori to the real biodiversity. For that reason every concept of species creates its own "virtual reality". Various concepts of species are not mutually comparable, and can not be criticized from each other's views and from position of "reality". Biological and Phylogenetic Species Concepts competing in ornithology exclude each other completely, and the unified concept of species is principally impossible. But as generally accepted species "standard" is needed, the unified convention of species must take the place of the various concepts of species.

Animals↗

PubMed2003

Hormonal characteristics in the early luteal phase of conceptive and nonconceptive menstrual cycles.

To determine whether serum hormone profiles are different in nonconceptive and conceptive menstrual cycles after ovulation and before implantation. Daily blood samples obtained during the luteal phase of nonconceptive cycles (n = 31) and conceptive cycles (n = 19) were analyzed (intersubject comparison). Samples obtained in sequential nonconceptive and conceptive cycles from five subjects (intrasubject comparisons) were analyzed to confirm results obtained with intersubject analysis. Serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E(2)), progesterone, and relaxin were measured by immunoassay. A cell-based bioassay was used to determine whether the measurement of serum immunoreactive LH is a result of cross-reaction with human chorionic gonadotropin (hCG). Intersubject analysis showed that mean serum LH levels were significantly higher in conceptive cycles on day 4 and day 5 after the FSH peak in urine, and this was confirmed by intrasubject analysis. The addition of antibodies that precipitate hCG did not affect the activity of LH receptor ligand molecules in serum samples collected during the early luteal phase of conceptive cycles, as measured by bioassay. In contrast, this LH receptor binding activity was completely removed when precipitating antibodies for LH were added. The mean levels of serum E(2) were higher in conceptive cycles after day 4 following the FSH peak in urine. The mean values of serum FSH, progesterone, and relaxin were not significantly different in nonconceptive and conceptive cycles during the same time interval. The differences in luteal phase hormones may reflect alterations in signaling in the hypothalamic-pituitary-ovarian axis that begin during the preovulatory period of nonconceptive cycles.

Adult↗

PubMed1992

Concept analysis methodology: applications to altered level of consciousness.

Concept analysis is the first step in instrument development. Steps in the concept analysis process are discussed and applied to the analysis of altered level of consciousness (ALC) as a potential nursing diagnosis for submission to the North American Nursing Diagnosis Association. Criteria regarding ALC have been defined for the assessment of neurologically impaired patients and not for the neurologically intact postanesthesia patient. It is assumed that postanesthesia patients experience chemically induced ALC, and consensus regarding what constitutes this concept needs to be validated by PACU nurses. The first step in instrument development is a clear definition of the concept of interest. The criteria for ALC determined by the PACU nurses could then be used to construct a pencil-and-paper instrument that would allow the concept to be tested on postanesthesia patients as they emerge from anesthesia. This concept analysis-to-instrument development process discussion can be applied to any concept of interest to the PACU nurse.

Consciousness↗

PubMed1992

Concept graphics: a language for medical knowledge.

This paper makes a case for Concept Graphics, a novel form of medical knowledge representation. Concept Graphics are assemblies of icons each of which has a precise meaning. Individual icons are metaphors of the object or process they represent. Concept Graphics are analogs of pathological situations, their symptoms, signs and other relevant components necessary for a diagnosis. We propose three principal areas of application for Concept Graphics: medical education, medical records management and research based on medical records. Our earlier work in medical education showed a clear advantage in using Concept Graphics in parallel with text of equivalent information content, over text alone. A Concept Graphics based intelligent tutoring systems (ITS) is being developed. In the area of medical records management we are developing a system for the rapid identification of relevant records based on rapid visual screening. The Concept Graphics based system can reveal properties common to specific groups of records. As such the graphics are a research tool.

Computer Graphics↗

PubMed2004

[Hopelessness: a concept analysis].

Hopelessness means no hope, the feeling that hopes have been destroyed or of facing a dilemma that cannot be solved. It is a subjective emotion which has a negative viewpoint for the future--one of losing control, confidence, courage and the energy to reach one's goal. Hopelessness can threaten a patient's physical and psychological well-being, and affect the process of recovery and rehabilitation. There is a great deal of relevant literature which explores the influence of hopelessness but there is no literature to analyze the concept of hopelessness. Therefore, the purpose of this article is to elucidate the concept of hopelessness, using a technique of concept analysis described by Walker and Avent (1995). In this concept analysis of hopelessness, the term is defined and the critical attributes are identified. Model, borderline, and contrary cases illustrate what the concept is and what it is not. The antecedents and consequences of hopelessness are identified to further refine the critical attributes. The article enhances a nurse's correct view of this concept and offers the concept for use in clinical nursing.

Depression↗

PubMed2004

A comparative study on concept representation between the UMLS and the clinical terms in Korean medical records.

The Unified Medical Language System (UMLS) is a rich source of knowledge in the biomedical domain. In this paper, we evaluated the coverage of UMLS as compared with Korean medical terms and identified differences in concept representation between two vocabulary sets. We measured the concept coverage by mapping clinical terms extracted from the discharge records of Seoul National University Hospital (SNUH) and the UMLS "Sign or Symptom" and "Disease or Syndrome" concepts. Thirty-five percent of the complaints in the SNUH were conceptually matched with the UMLS "Sign or Symptom" concept. Fifty-eight percent were found to be matched with the UMLS "Disease or Syndrome" concept rather than the "Sign or Symptom" concept. The remaining seven percent were not found in the UMLS concepts mapped above or those terms that used to special circumstances of a tertiary hospital in Korea. We then analyzed some of different expression patterns used by the two vocabulary sets and addressed issues to be taken into consideration.

Humans↗

PubMed1992

Biomechanical and orthopedic concepts in sport shoe construction.

Two sets of concepts for sport shoe construction are discussed, based on anatomical, orthopedic, and epidemiological considerations: one for the prevention of excessive load and related injuries, and one for the improvement of performance. The proposed concepts for prevention of excessive load and related injuries in the foot and the lower extremities are cushioning, support, and guidance. The goals outlined in the concepts can be achieved by altering the material properties or the construction of the shoe. It is suggested that the concept "cushioning" is not well understood yet and needs further research. The discussed concepts for improving performance are first, that energy should be returned at the right location, at the right time, with the right frequency, and second, that loss of energy should be minimized. Reduction of energy loss is an important concept for performance. The concept "return of energy" seems inappropriate for sport shoes.

Athletic Injuries↗

PubMed2005

Identifying UMLS concepts from ECG Impressions using KnowledgeMap.

Electrocardiogram (ECG) impressions represent a wealth of medical information for potential decision support and drug-effect discovery. Much of this information is inaccessible to automated methods in the free-text portion of the ECG report. We studied the application of the KnowledgeMap concept identifier (KMCI) to map Unified Medical Language System (UMLS) concepts from ECG impressions. ECGs were processed by KMCI and the results scored for accuracy by multiple raters. Reviewers also recorded unidentified concepts through the scoring interface. Overall, KMCI correctly identified 1059 out of 1171 concepts for a recall of 0.90. Precision, indicating the proportion of ECG concepts correctly identified, was 0.94. KMCI was particularly effective at identifying ECG rhythms (330/333), perfusion changes (65/66), and noncardiac medical concepts (11/11). In conclusion, KMCI is an effective method for mapping ECG impressions to UMLS concepts.

Abstracting and Indexing↗

PubMed1989

[Measurement of dentists' treatment conceptions].

It was hypothesized that dentists have different conceptions of treatment. A distinction was made between a relational dimension with extremes a communicative and a directive conception and a dental dimension with extremes a restorative and a preventive conception. For the measurement of the conceptions a questionnaire of fourty-three items was constructed. The questionnaire was administered to 149 dentists in The Netherlands. Using factor analysis eleven items were selected for the relational dimension and also eleven items for the dental dimension. Cronbach's coefficient alpha is .75 for the relational dimension and .78 for the dental dimension; the correlation of the two dimensions is .21. Therefore, the conceptions can be measured using the questionnaire. The conception of the dentists is in general communicative; the variation between the restorative and preventive conceptions is rather large.

Attitude of Health Personnel↗