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PubMed2005

Treatment concepts of day hospitals for general psychiatric patients. Findings from a national survey in Germany.

Psychiatric day hospital treatment concepts have to deal with a wide spectrum of mental disorders. We raised the question, if day hospitals can be differentiated concerning their treatment concepts and if so how much this is reflected in their structural and procedural features. In 1999 a survey was initiated concerning structure, concept and method of treatment in psychiatric day hospitals for adults in Germany. Furthermore data concerning rate of utilization, patients' characteristics and aspects of referral and further treatment were ascertained. One hundred and seventy-three (63.4%) of 273-day hospitals contacted took part in the inquiry. The data were interpreted using multivariate as well as non-parametric procedures. The results show that treatment concepts of day hospitals can be specified as three main areas of function (psychotherapy, crisis intervention orientated treatment alternative, rehabilitation) and four therapeutic orientations (psychodynamic social psychiatric, behavioral social psychiatric, psychodynamic, sociotherapeutic). Structural features are predominantly comparable and the differences found concerning the treatment concepts are especially related to patients' characteristics and some procedural features. The conclusion is that the differentiation of day hospital treatment concepts should be taken into consideration in planning psychosocial treatment services as well as in day hospital evaluation research.

Adult↗
PubMed2005

A novel view on information content of concepts in a large ontology and a view on the structure and the quality of the ontology.

Semantic distance and semantic similarity are two important information retrieval measures used in word sense disambiguation as well as for the assessment of how relevant concepts are with respect to the documents in which they are found. A variety of calculation methods have been proposed in the literature, whereby methods taking into account the information content of an individual concept outperform those that do not. In this paper, we present a novel recursive approach to calculate a concept's information content based on the information content of the concepts to which it relates. The method is applicable to extremely large ontologies containing several million concepts and relationships amongst them. It is shown that a concept's information content as calculated by this method provides additional information with respect to an ontology that cannot be approximated by hierarchical edge-counting or human insight. In addition, it is suggested that the method can be used for quality control within large ontologies and that it can give you an impression on the structure and the quality of the ontology.

Algorithms↗
PubMed2005

The effect of strain of Holstein-Friesian cow and feeding system on postpartum ovarian function, animal production and conception rate to first service.

Three strains of Holstein-Friesian (HF): high production North American (HP), high durability North American (HD) and New Zealand (NZ) cows were assigned, within strain, to one of three pasture-based feeding systems: (1) the Moorepark (control) system (MP), (2) a high concentrate system (HC), (3) a high stocking rate system (HS). Ovarian function was assessed using milk progesterone samples, collected from 117 cows in each of two successive years, with 81 animals being common to both years. Milk samples were collected thrice weekly, beginning day 5 post-calving and continued to day 26 after first AI. Data from animals subsequent to reproductive hormonal treatment were removed from the analysis. Feed system and strain of HF by feeding system interaction had no significant effect on re-establishment of ovarian activity and subsequent conception rate to first AI. Strain of HF had no significant effect on interval to commencement of luteal activity (CLA). The mean interval to CLA was 32.9 days (S.E. 1.18), ranged from 6 to 100 days, with 42 and 85% of cows ovulating by day 26 and 60, respectively. The HD (62%) and NZ (57%) strains had a higher conception rate to first AI than the HP strain (40%), (P < 0.05). Retrospective analysis categorised all cows into four quartiles based on interval to CLA (< 20 days, 20-26 days, 27-44 days and > 44 days). Cows in the first and fourth CLA quartiles had a longer calving to conception interval (P < 0.05). Cows with abnormal progesterone profiles (38.4%) had an earlier mean calving date, with a similar submission rate and conception rate to first service compared to cows with normal hormonal profiles. There was no significant difference in luteal activity or reproduction performance, apart from calving to conception interval, between cows that conceived or did not conceive to first service. These results indicate that while conception rate to first service differed between strains of HF cow, this was not associated with differences in the onset and pattern of luteal activity post partum.

Animal Feed↗
PubMed2005

Conception rate after fixed time insemination following ovsynch protocol with and without progesterone supplementation in cyclic and non-cyclic Mediterranean Italian buffaloes (Bubalus bubalis).

The aim of this study was to test the effect of progesterone supplementation to Ovsynch protocol in cyclic and non-cyclic Mediterranean Italian buffaloes on conception rate after fixed time artificial insemination. From 169 pluriparous buffaloes, 2 groups were identified and subjected to: (1) Ovsynch protocol (OV; n=83) and (2) Ovsynch protocol with the supplementation of progesterone from days 0 to 7 (OV+PROG.; n=86). All cows were inseminated 16-20 h after the second GnRH administration. Within each group, non-cyclic buffaloes were identified (OV=21 and OV+PROG.=20). Overall conception rate was significantly higher in cyclic compared to non-cyclic buffaloes: 43.7% versus 17.0%, respectively, P=0.001. A significant effect of progesterone supplementation on conception rate was observed in non-cyclic buffaloes (30% versus 4.7%, P=0.04) but not in cyclic buffaloes (51.5% versus 35.7%, P=0.077). Collectively, the presence of a large follicle (>or=10 mm) detected at the beginning of the Ovsynch protocol by ultrasound significantly affected conception rate (44% versus 8%, P=0.01). The findings of the present study suggest that (i) progesterone supplementation to the Ovsynch protocol in buffaloes increases conception rate in non-cyclic animals, (ii) the presence of a large follicle at the beginning of the Ovsynch protocol is a determining factor for a successful synchronization of ovulation and high conception rates and (iii) ultrasound monitoring can improve the overall efficiency by selectively identifying more suitable cycling animals carrying a responsive follicle at the time of first GnRH administration.

Animals↗
PubMed2004

Effect of semen thaw method on conception rate in four large commercial dairy heifer herds.

Semen processed with procedures intended to permit a flexible thaw method is used to breed millions of cows yearly. One method of thawing straws, the "pocket thaw" is used extensively with semen prepared with these procedures. Published field data is lacking for thaw method comparisons with semen processed to permit flexible-thawing. The objective of the present study was to measure the effect of semen thaw method (warm-water or pocket thaw) over all seasons and its interaction with herds, inseminators, straw package size, and sperm number on conception rate in commercial dairy heifer herds using semen processed with procedures historically optimized for success with flexible-thawing. Professional inseminators performed 11,215 services over a 16-month period in four large herds, achieving a 67.6% conception rate. Thaw method was alternated weekly. Thaw effect on conception status, determined by 70 days non-return rate, was estimated by a generalized linear mixed model. Neither thaw method nor number of sperm per straw significantly affected probability of conception (P=0.658 and 0.769, respectively). No interactions of thaw method with herd, sperm number, season, straw size, and straw size by season were detected (P=0.297, 0.526, 0.365, 0.723, and 0.824, respectively). Bull, herd, inseminator within herd, year, season, and straw size affected conception rate (P=0.002, 0.000, 0.000, 0.000, 0.000, and 0.014, respectively). In conclusion, for semen processed with procedures that permit flexible-thawing, thaw method (pocket thaw versus warm-water thaw) did not affect conception rate under commercial conditions and with routine semen handling methods.

Animals↗
PubMed2001

Differences in hormonal characteristics of conceptive versus nonconceptive menstrual cycles.

OBJECTIVE: To determine the hormonal characteristics of a fecund menstrual cycle. DESIGN: Prospective observational study. SETTING: Clinical research center. PATIENT(S): Fourteen patients having artificial insemination with donor semen provided daily blood and urine samples in a nonconceptive cycle and the consecutive conceptive cycle. INTERVENTION(S): Concentrations of E2, luteinizing hormone, follicle-stimulating hormone (FSH), and P4 were measured in serum. Urine samples were analyzed for metabolites of E2, P4, and FSH. MAIN OUTCOME MEASURE(S): The serum and urinary hormone profiles of the periovulatory period were compared in conceptive and nonconceptive cycles. RESULT(S): The mean peak value of periovulatory urinary FSH was significantly higher in conceptive cycles than in nonconceptive cycles. The mean serum E2 concentration was significantly higher on day 0 (day of peak urinary FSH concentration) in conceptive cycles than in nonconceptive cycles, but mean peak values of serum E2 did not differ significantly. No other significant differences were observed in serum and urinary hormone profiles between conceptive and nonconceptive cycles. CONCLUSION(S): A lower, broader peak of FSH in urine was observed in nonconceptive cycles compared with conceptive cycles. Urinary FSH measurements may be useful in predicting less fecund ovulatory cycles and may identify some types of reduced female fertility.

Adult↗
PubMed1999

Spontaneous conception after the birth of infants conceived through in vitro fertilization treatment.

OBJECTIVE: To investigate the incidence of spontaneous conception after the birth of infants conceived through IVF in couples with subfertility caused by endometriosis, a mild male factor, or unexplained factors, and to identify clinical conditions related to the occurrence of spontaneous conception. DESIGN: Retrospective analysis. SETTING: Department of Obstetrics and Gynecology, Akita University School of Medicine, Akita, Japan. PATIENT(S): One hundred forty-two women who conceived through IVF and 25 of the 142 women who subsequently conceived spontaneously. INTERVENTION(S): Patient characteristics and IVF data were obtained from hospital records, and follow-up data were collected through telephone interviews. MAIN OUTCOME MEASURE(S): Cumulative conception rate. RESULT(S): The cumulative conception rate at 60 months after the delivery of infants conceived through IVF was 18%, with most conceptions occurring within 2 years of delivery. Proportional hazard analysis indicated that patient age was the most important clinical variable related to the occurrence of spontaneous conception. CONCLUSION(S): This study provides information that will be useful in counseling subfertile couples who have conceived through the use of IVF.

Adult↗
PubMed1998

Current concepts of fetal growth restriction: part I. Causes, classification, and pathophysiology.

OBJECTIVE: To update basic concepts and management strategies of fetal growth restriction (FGR). DATA SOURCE: An English literature search was conducted for pertinent articles related to FGR from 1976 to 1997. Original research articles, review articles, and book chapters were reviewed. METHODS OF STUDY SELECTION: This study was divided into two parts. For this article, both human data and animal data pertinent to understanding causative factors, pathogenesis, clinical type, and pathophysiology were included. To perform a meaningful comparison, the concept of investigators and their methods of investigation were critically compared between the two study periods: 1976-1985 and 1986-1997. TABULATION, INTEGRATION, AND RESULTS: Older concepts involving basic principles of FGR based on animal models during the first study period were integrated with new research findings obtained from human FGR during the second study period. By comparative analysis of older animal data and new human data, current concepts of FGR were synthesized. CONCLUSION: Fetal growth restriction affects a heterogenous group of infants. Despite development of new technology for investigation, many older basic concepts related to FGR are still fundamentally sound. However, new investigations directly performed on human fetuses are a useful expansion of the older concepts.

Animals↗
PubMed2003

Influence of stage of lactation and milk production on conception rates after timed artificial insemination following Ovsynch.

Conception rates after timed artificial insemination (TAI) are of paramount importance for the success of protocols based on synchronization of ovulation. Stage of lactation and milk production level are known factors that influence dairy cow fertility. It was the objective of this study to analyse the effect of stage of lactation and milk production level on conception rates and pregnancy rates by 200 days in milk (DIM) in dairy cows synchronized with the Ovsynch protocol (Day -10, Day -1: 0.1 mg of D-Phe6-gonadorelin, Day -3: 0.5 mg of cloprostenol, Day 0: AI). A total of 1,288 dairy cows were assigned to two groups and classified in three production levels (high, average, low). Cows of all milk production levels in Group 1 (Simultaneous Ovsynch, SO) were synchronized with the Ovsynch protocol simultaneously for TAI between 73 and 81 DIM. In Group 2 cows with average milk production were synchronized at the same time as Group 1, while low producing cows were synchronized 3 weeks earlier and high producing cows were synchronized 3 weeks later than Group 1, respectively. First service conception rates (FSCRs) were lower (P<0.05) in cows synchronized earlier than in cows of the same production level synchronized later (low production: 14.4% (22/153) versus 34.5% (51/148); high production: 28.2% (40/142) versus 41.4% (53/128)). Milk production level had no significant impact on conception rates after TAI in cows synchronized at the same stage of lactation. At 200 DIM fewer cows with high production level were pregnant than cows with average or low production (P<0.05). This effect was independent of the stage of lactation at the initiation of Ovsynch. Endometritis at a postpartum examination did not influence conception rates after TAI. In conclusion, stage of lactation, but not milk production level, has a major influence on conception rates after TAI. Early AI after Ovsynch is less efficient and therefore its return on investment should be evaluated carefully.

Animals↗
PubMed1999

Conception rates after artificial insemination or embryo transfer in lactating dairy cows during summer in Florida.

The objective was to compare conception rates to embryo transfer relative to AI, during summer heat stress, in lactating dairy cows. Holstein cows (n = 180; 50 to 120 d postpartum) were allocated randomly to 1 of 3 groups: artificial insemination (AI, n = 84), embryo transfer using either embryos collected from superovulated donors (ET-DON, n = 48), or embryos produced in vitro (ET-IVF, n = 48). Embryos from superovulated donors were frozen in 10% glycerol and were rehydrated in a 3-step procedure, in decreasing concentrations of glycerol in a sucrose medium before transfer. Embryos produced in vitro were frozen in 1.5 M ethylene glycol, thawed and transferred without rehydration. Blood samples were collected from AI and ET recipients on Days 0, 7 and 22 for measurement of progesterone in plasma. Conception rate was estimated for the three groups at Day 22 (progesterone > 1 ng/mL) and confirmed at Day 42 by palpation per rectum. Conception rate estimates at Day 22 did not differ among groups (AI, 60.7%; ET-DON, 60.4%; ET-IVF, 54.2%), but conception rates at Day 42 differed (AI, 21.4%; ET-DON, 35.4%; ET-IVF, 18.8%; AI versus ET: P > 0.10 and ET-DON versus ET-IVF: P < 0.05). In cows considered pregnant at 22 d but diagnosed open at 42 d, the interestrous intervals were 28.8 +/- 2.2, 35.2 +/- 3.5 and 31.6 +/- 2.9 d, respectively, for AI, ET-DON and ET-IVF groups. Transfer of embryos collected from nonheat-stressed superovulated donors significantly increased conception rates in heat stressed dairy cattle. However, transfer of IVF-derived embryos had no advantage over AI. Where appropriate mechanisms are in place to attenuate the effects of heat stress, embryo transfer using frozen-thawed donor embryos increases conception rates.

Animals↗
PubMed2002

Whatever happened to the 'microtrabecular concept'?

Keith Porter culminated his stellar career as the founding father of biological electron microscopy by acquiring, in the late 1970s, a high-voltage electron microscope (HVEM). With this magnificent instrument he examined whole-mounts of cultured cells, and perceived within them a structured cytoplasmic matrix he named the "microtrabecular lattice". Over the next decade Porter published a series of studies, together with a team of outstanding young colleagues, which elaborated his broader "microtrabecular concept." This concept posited that microtrabeculae were real physical entities that represented the fundamental organization the cytoplasm, and that they were the physical basis of cytoplasmic motility and of cell-shape determination. The present review presents Porter's original images of microtrabeculae, after conversion to a more interpretable "digital-anaglyph" form, and discusses the rise and fall of the microtrabecular concept. Further, it explains how the HVEM images of microtrabeculae finally came to be considered as an artifact of the preparative methods Porter used to prepare whole cells for HVEM. Still, Keith's "microtrabecular concept" foretold of our current appreciation of the complexity and pervasiveness of the cytoskeleton, which has now been found by more modern methods of EM to actually be the fundamental organizing principle of the cytoplasmic matrix. During the impending eclipse of Porter's microtrabecular concept in the late 1980s, many of Keith's colleagues fondly described the cell as being filled, not with protoplasm, but with "Porterplasm." Despite the fact that Keith's view was clouded by the methods of his time, it would be fitting and apt to retain this name, still today, for the ordered matrix of cytoskeletal macromolecules that exists in the living cell. In the end, the story of what happened to Porter's microtrabecular concept should be an object lesson in scientific hubris that should humble and inform all of us in cell biology, even today--particularly when we begin to think that our most recent methods and observations are achieving "the last word".

Animals↗
PubMed2004

The use of concept mapping to enlighten the knowledge networks of diabetic children: a pilot study.

OBJECTIVE: The value of concept mapping in enlightening nature and organization of knowledge was shown with adult diabetic or obese patients. Our objectives were to ascertain the relevance and feasability of concept mapping in diabetic children during an educational program. METHOD: This qualitative research was performed in 5 children from 8 to 13 years. Concept maps were drawn at the beginning (Phase 1) and at the end (Phase 2) of an educational program. During the interview each child was invited to express himself starting from the central concept: "diabetes", and to express his/her knowledge, representations, and life experience. RESULTS: The ten maps analysis shows: an increase of knowledge between phase 1 and phase 2 (+34%), towards a deepening of initial knowledge and an addition of new knowledge (43% and 41% of the added knowledge); a decrease of inaccurate knowledge in phase 2; an enrichment of the knowledge networks (+16 cross links); an increase of knowledge related to the ways to behave knowledge (+42%). CONCLUSION: This preliminary report demonstrated that concept maps were feasible, useful and relevant in therapeutic education of children. This method allowed us to show how every child connected his knowledge and how it was modified by an educational intervention. Concept maps therefore contributed to individual educational diagnosis and assessment of new knowledge integration.

Adolescent↗
PubMed2004

Prospective study of parental choice for aneuploidy screening in assisted conception versus spontaneously conceived twins.

The aim of this study was to evaluate and compare parental choice towards the use of aneuploidy screening and diagnostic techniques after assisted conception versus spontaneously conceived pregnancy. A total of 193 patients with consecutive twin pregnancies participated in the study, including 143 who spontaneously conceived and 50 who conceived following assisted reproduction treatment. Patients were investigated prospectively for their choice in the prenatal screening/diagnosis of aneuploidy. In the group of patients who conceived spontaneously, 111 (77.6%) opted initially for the non-invasive screening based on nuchal translucency measurements, whereas in the assisted conception group, 44 (88%) opted for the non-invasive screening. In the spontaneous conception group, 32 (22.4%) presented because they had a positive serum screening test or because they had opted for a chorionic villus sampling (CVS) or an amniocentesis for advanced maternal age. In the assisted conception group only six patients (12%) opted for amniocentesis. The difference in choice of noninvasive versus invasive screening between those with spontaneous and those with assisted conception was not significant, but those who had conceived spontaneously after the age of 37 years were significantly more likely (P < 0.05) to request an invasive diagnostic procedure through all maternal age groups. When needed, an amniocentesis was preferred to CVS. These data also indicate that the antenatal counselling needs to be adapted to couples presenting with an assisted conception twin pregnancy.

Adult↗
PubMed2002

Mismatched concepts in a neonatal intensive care unit (NICU): further issues for computer decision support?

BACKGROUND: Common concepts and definitions are important for the effective practice of medicine. In an intensive care unit clear understanding of terminology and communication between different staff groups may be critical for optimal care. If computerised decision support tools are to be successfully deployed in these high intensity environments, all staff must understand the concepts and information that is to be portrayed. OBJECTIVE: To examine the similarity of language and concepts related to newborn infants and their care in staff groups with different experience. METHODS: An experimental study in a tertiary regional neonatal intensive care unit involved 32 staff in 4 groups with varying experience (junior and senior / nurses and doctors). A psychologist developed a lexicon of clinical actions and a second lexicon of possible patient descriptors applicable to newborn infants receiving all degrees of neonatal care by conducting interviews with staff on the unit. Card sorting experiments were performed on the terms in the action and descriptor lexicons, the staff being asked to group words that were related to the same or similar concepts. The card sort data were analysed using conventional cluster analysis to produce tree-diagrams or dendrograms and then by distance matrix analysis to give cumulative probability plots. RESULTS: Differences were shown in the way various classes of staff and staff with different experience mentally map clinical concepts. Clinical actions were grouped more randomly by nurses and by those with less experience with a polarisation between senior doctors and junior nurses. Descriptors were classed more definitively and similarly by junior and senior nurses and senior doctors but more randomly and quite differently by junior doctors. Thus there were differences seen between nurses and doctors with different roles within the unit and differences related to experience. CONCLUSIONS: Concepts are used differently by various staff groups in a neonatal unit: this may have an impact on the effectiveness of computerised decision aids unless it is taken into account during their development.

Adult↗
PubMed2003

The shortened dental arch concept--attitudes of dentists in Tanzania.

OBJECTIVES: The shortened dental arch concept is a problem-oriented strategy to reduce complex restorative treatment in the posterior regions. The aim of this study was to determine the attitude of Tanzanian dentists about this concept. METHODS: A questionnaire was sent to all 77 dentists treating patients in Tanzania. The questionnaire contained items to assess the dentist's opinions such as dentist's judgement about the oral function of subjects with shortened dental arches, the type of treatment (or no treatment) of subjects with shortened dental arches and the reactions of patients to the proposal to shorten the dental arch. A short description about the problem-oriented approach and the shortened dental arch concept was included. RESULTS: Most of the responding dentists judged that shortened dental arches can provide satisfactory or acceptable chewing function (71%) and dental appearance (79%). Most dentists (89%) indicated that the shortened dental arch concept, as an example of a problem-oriented approach, has a useful place in clinical practice. However, most dentists (89%) inserted free-end acrylic partial dentures in these cases. Dentists with experience to apply the concept indicated that most of the patients have no objections after explanation of the proposal to shorten the dental arch. CONCLUSIONS: From this study it is concluded that the shortened dental arch concept is an acceptable strategy for dentists in Tanzania. However, many dentists doubt its implementation in clinical practice.

Attitude of Health Personnel↗
PubMed1996

A concept analysis of trust.

Trust is an important and pervasive concept. In nursing, it has been considered primarily from two perspectives. Clinically, it is an important aspect of the nurse-patient relationship. Organizationally, trust is associated with various outcomes and levels of effectiveness. Much of the nursing literature that discusses trust relies upon vague conceptualizations or borrows from other disciplines. The absence of a clear conceptualization of trust has been cited. A core concept of trust is presented which is applicable to nursing in both clinical and organizational settings. Established methods for concept analysis are supplemented by a sequential step model developed by the author. The concept is developed as both process and outcome, and the relationships of the two states to measurement of the concept are identified. The utilization of the core concept in context-specific instances is discussed, and suggestions are made for further research.

Attitude to Health↗
PubMed1998

Lecturer practitioner: a concept analysis.

The concept of the lecturer practitioner arose in one health authority in Britain in the late 1980s. Since its inception there, the concept has been widely adopted across the country suggesting that there is a perceived need for this role. However, there is much confusion over what a lecturer practitioner is, since each post is multifaceted, complex and unique. Rodgers' (1993) evolutionary concept analysis is used in an attempt to clarify and to identify those elements that are common to this concept. Through a review of all the available literature on this concept, the attributes, antecedents and consequences are identified and their implications discussed. Rodgers' evolutionary method is described and critiqued throughout the paper and is shown to be a suitable method for clarifying a complex concept.

Faculty, Nursing↗
PubMed2002

An analysis of the concept of equity and its application to health visiting.

AIMS: The aim of this paper is to provide an in-depth analysis of the concept of equity in the British health visiting service and thus facilitate understanding of the term. An attempt has been made to apply the analytical process to the context of health visiting. BACKGROUND: Equity has been discussed at some length in the health literature. Much of this including the health visiting literature discusses inequality and inequalities in health at the same time as discussing equity. Increasingly, poverty and inequalities have become accepted as determinants in poor health. It seemed appropriate therefore to analyse these topical and seemingly related concepts. METHODS: A well established method of concept analysis has been utilized to facilitate the process of analysis. RESULTS: Confusion between the meaning and application of the concepts of equity and equality was found. Much of the health visiting and health care literature related to addressing the needs of groups who experience inequality in terms of service provision, and access to services. Following an in-depth critical analysis of the literature three critical attributes of the concept were identified: equal opportunity of access to services; a high standard of service for everyone; and unequal distribution of services to meet unequal need. These relate to two distinct forms of equity: horizontal and vertical equity. A definition of equity has been proposed. Maxwell's (1992) framework is suggested as a means to evaluate equity in service provision and uptake. CONCLUSIONS: Most of the literature examines equity at a macro level, that is service level. Nurses and health visitors are urged to examine the services that they are involved in to determine the level of equity that is achieved or not attained. Suggestions have been offered as to how this task may be undertaken. A definition has been proposed to stimulate debate and discussion about the concept within nursing contexts.

Community Health Nursing↗