Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Conversation analysis”

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 793 records · Page 44Linked to original sources

Recent advances in capillary electrophoresis of peptides.

The article gives a comprehensive review on the recent developments in the applications of high-performance capillary electromigration methods, including zone electrophoresis, isotachophoresis, isoelectric focusing, affinity electrophoresis, electrokinetic chromatography and electrochromatography, to analysis, preparation and physicochemical characterization of peptides. The article presents new approaches to the theoretical description and experimental verification of electromigration behavior of peptides, and covers the methodological aspects of capillary electroseparations of peptides, such as strategy and rules for the rational selection of separation mode and experimental conditions, sample treatment, suppression of peptide adsorption to the inner capillary wall, new developments in individual separation modes and new designs of detection systems. Several types of applications of capillary electromigration methods to peptide analysis are presented: conventional qualitative and quantitative analysis for determination of purity, determination in biomatrices, monitoring of physical and chemical changes and enzymatic conversions, amino acid and sequence analysis and peptide mapping of proteins. Some examples of micropreparative peptide separations are given and capabilities of capillary electromigration techniques to provide important physicochemical characteristics of peptides are demonstrated.

Electrophoresis, Capillary↗

Shrinkage of abdominal aortic aneurysm after successful endovascular repair: results from single center study.

AIM: In the literature, the behavior of the aneurysm sac after endovascular grafting has been the subject of significant speculation. It has been suggested that shrinkage of the abdominal aortic aneurysm (AAA) is different for various endografts. This study was undertaken to evaluate endograft-specific differences in aneurysm sac shrinkage and to evaluate other factors that may influence AAA shrinkage. METHODS: Forty patients with an AAA treated with endovascular grafts with a complete 18 months follow-up and complete CT angiography (CTA) follow-up were available for analysis. All patients with a persistent endoleak, endograft migration or any other reason for intervention or conversion were excluded from this analysis. Shrinkage was defined as a reduction in the AAA diameter of 5 mm or more. Chi-squared tests were used to test whether shrinkage was different for the kind of stent graft used (Gore Excluder vs Cook-Zenith), preexistent AAA diameter (<65 mm vs =or>65 mm), and AAA status (ruptured vs non-ruptured) (two-sided; a= 0.05). RESULTS: At 18 months after treatment, shrinkage was observed in 14 patients (52%) of the 27 patients treated with a Gore Excluder endograft and in 8 patients (62%) of the 13 patients treated with a Cook Zenith endograft (P=0.74). In 31 patients with a diameter <65 mm, shrinkage was observed in 19 patients (61%) whereas of the 9 patients with a diameter =or>65 mm, shrinkage was observed in 3 patients (33%) (P=0.253). Of the 34 patients with a non-ruptured AAA, shrinkage was observed in 18 patients (53%) versus of the 6 patients with a ruptured AAA shrinkage was observed in 4 patients (66%) (P=0.673). CONCLUSIONS: From this study can be concluded that the influence of the endograft on shrinkage of the AAA sac might be less prominent than suggested in the literature. Furthermore, our study shows that other factors such as preexistent AAA diameter may influence AAA shrinkage after endovascular repair.

Aged↗

Oral propafenone to convert recent-onset atrial fibrillation in patients with and without underlying heart disease. A randomized, controlled trial.

BACKGROUND: The effectiveness of oral propafenone in converting recent-onset atrial fibrillation to sinus rhythm has been established by controlled trials. However, it is not clear whether the effectiveness of propafenone is affected by the presence or absence of underlying heart disease. OBJECTIVES: To investigate the safety and effectiveness of oral propafenone and the role of underlying heart disease. DESIGN: Randomized, single-blind, controlled study. SETTING: 3 teaching hospitals. PATIENTS: 240 hospitalized patients with recent-onset atrial fibrillation. INTERVENTION: Propafenone (one 500-mg oral dose) or placebo. MEASUREMENTS: Conversion rates at 3 and 8 hours. RESULTS: Propafenone was more effective than placebo for converting atrial fibrillation to sinus rhythm at 3 hours: Fifty-four of 119 patients (45%) receiving propafenone and 22 of 121 patients (18%) receiving placebo had conversion (P < 0.001). It was also more effective at 8 hours: Ninety-one of 119 patients (76%) receiving propafenone and 45 of 121 patients (37%) receiving placebo had conversion (P < 0.001). Subgroup analysis showed that among patients without heart disease, 78% of those receiving propafenone and 56% of those receiving placebo converted to sinus rhythm within 8 hours (P = 0.02). In those with hypertension, the rate was 70% for those receiving propafenone and 27% for those receiving placebo (P < 0.001); in patients with structural heart disease, the rate was 81% for those receiving propafenone and 17% for those receiving placebo (P < 0.001). CONCLUSIONS: Oral loading of propafenone was more effective than placebo for conversion to sinus rhythm within 8 hours and had a favorable safety profile. The rate of spontaneous conversion to sinus rhythm was higher in patients without structural heart disease; this finding has important implications for the assessment of drug effectiveness in recent-onset atrial fibrillation.

Administration, Oral↗

Genetic analysis of the ADGF multigene family by homologous recombination and gene conversion in Drosophila.

Many Drosophila genes exist as members of multigene families and within each family the members can be functionally redundant, making it difficult to identify them by classical mutagenesis techniques based on phenotypic screening. We have addressed this problem in a genetic analysis of a novel family of six adenosine deaminase-related growth factors (ADGFs). We used ends-in targeting to introduce mutations into five of the six ADGF genes, taking advantage of the fact that five of the family members are encoded by a three-gene cluster and a two-gene cluster. We used two targeting constructs to introduce loss-of-function mutations into all five genes, as well as to isolate different combinations of multiple mutations, independent of phenotypic consequences. The results show that (1) it is possible to use ends-in targeting to disrupt gene clusters; (2) gene conversion, which is usually considered a complication in gene targeting, can be used to help recover different mutant combinations in a single screening procedure; (3) the reduction of duplication to a single copy by induction of a double-strand break is better explained by the single-strand annealing mechanism than by simple crossing over between repeats; and (4) loss of function of the most abundantly expressed family member (ADGF-A) leads to disintegration of the fat body and the development of melanotic tumors in mutant larvae.

Animals↗

Absence of interference in association with gene conversion in Sordaria fimicola, and presence of interference in association with ordinary recombination.

From the analysis of large samples of gene conversion asci in the g locus of Sordaria fimicola, it was found that neither the conversion event itself nor conversion-associated recombination of flanking markers cause either chiasma or chromatid interference with crossing over in a neighboring interval. The presence of more than one kind of crossover event, one causing interference the other not, is considered. The existence of two kinds of gene loci, one of single-cistron composition and the other of multiple-cistron composition, is discussed in relation to reciprocal recombination within a locus.

Gene Conversion↗

Cardiac patients' conversations and the process of establishing meaning.

The purpose of this study was to describe and analyze the naturally occurring conversations of hospitalized cardiac patients. According to Blumer's symbolic interactionist perspective, individual interpretation or the meaning of a stressful event is developed and shared through social interaction. The meaning of an event is the foundation for behavioral responses that can promote or impede recovery. This study analyzed the naturally occurring conversations of ten cardiac patients. Three themes were identified within these conversations. The first theme, labeled finding cause, incorporated the processes of structuring the illness event, determining a cause for the event, and sharing the story of the illness with someone. The second theme, labeled acting normally, included participants attempting to preserve their normal patterns or habits, to resume normal activities, and to maintain personal control. The third theme, labeled passing time, encompassed sequencing the experiences within the illness event and hospitalization, waiting for news about their condition and/or recovery and structuring their future following recovery from the acute illness. An analysis of naturally occurring conversation can expedite recognition of the processes cardiac patients use to structure their reality and determine the meaning of an illness event. This may provide a foundation for understanding behaviors that affect physiological and psychosocial recovery.

Adolescent↗

Conversion to soft-copy sonography: effects on imaging time and costs.

OBJECTIVE: To determine the effect of conversion to soft-copy interpretation on the number of images and imaging time. MATERIALS AND METHODS: Before and 1 year after conversion to soft-copy interpretation, 20 consecutive normal abdominal, renal, and cranial sonograms were performed by each of three technologists (360 sonograms total). The number of images and imaging time per sonogram were recorded. For each technologist and each examination type, the differences between number of images and the imaging times before and after conversion were compared. Multivariate repeated measures analysis of variance was used to analyze the data. RESULTS: After conversion to soft-copy, the number of images significantly increased for all imaging types (P = 0.004), and the imaging time significantly decreased (P < 0.001). After conversion, there were 213 more images. The average number of images increased 1.0 per abdominal sonogram, 0.5 per renal sonogram, and 2.0 per cranial sonogram. The additional storage requirement for the 213 images was 64 MB; total long-term storage media cost increased $1.06. On average, there was a 19% decrease in imaging time, with abdominal imaging time decreasing 2 min and 18 s, renal 1 min and 46 s, and cranial 40 s. This would potentially allow time for two additional sonograms to be performed per day and would generate up to $112,000 additional revenue per year. CONCLUSION: Following soft-copy conversion, there was a significant increase in the number of images acquired per examination, with an increased storage requirement but a negligible increase in storage cost. Technologist efficiency significantly improved.

Abdomen↗

Laparoscopic cholecystectomy for 58 end stage renal disease patients.

BACKGROUND: Since 1987, laparoscopic cholecystectomy (LC) has been widely used as the favored treatment for gallbladder lesions throughout the world. Because hemorrhage, infection, and delayed wound healing are the main causes of death after surgery for end-stage renal disease (ESRD), laparoscopic surgery is risky for ESRD patients. However, no information has been reported on such patients, so this study aimed to assess the safety of LC in ESRD patients. METHOD: From January 1994 to December 2003, the medical records of 58 ESRD patients under regular hemodialysis (HD) with gallbladder lesions undergoing LC were reviewed (ESRD-LC). The clinical features and outcomes of 6,182 patients with gallbladder lesions without ESRD undergoing LC were also summarized for comparison. RESULTS: Of 6,240 patients with gallbladder lesions undergoing LC, 58 (0.93%) had ESRD with regular HD. The ESRD-LC group clearly exhibited older age, higher frequency of associated disease, lower hemoglobin and platelet count, and elevated alkaline phosphatase, blood urea nitrogen, and creatinine values. However, only a higher frequency of high American Society of Anesthesiologists (ASA) grade and elevated creatinine value could differentiate ESRD-LC and LC patients by multivariate analysis. Similar blood loss, conversion rate, morbidity, mortality, and hospital stay were noted for the two groups. CONCLUSIONS: LC is safe for ESRD patients with gallbladder lesions. Only a higher frequency of high ASA grade and elevated creatinine value could differentiate ESRD-LC and LC patients. Similar blood loss, conversion rate, morbidity, mortality, and hospital stay were achieved by applying LC to treat ESRD patients. However, appropriate preoperative preparations and experienced operative techniques are still required to prevent mortality.

Adult↗

Effect of apparent ileal digestible lysine to energy ratio on performance of finishing pigs at different dietary metabolizable energy levels.

A study with a total of 96 crossbred barrows and gilts fed ad libitum in a body weight range of 56-110 kg was carried out in order to investigate whether the optimum ratio of apparent ileal digestible lysine : energy (ME) depends on the energy density of the diet. Dietary treatments were ratios of 0.34, 0.42, 0.50 and 0.58 g digestible lysine/MJ ME either at an energy density of 13 or 14 MJ ME. Body weight gain as well as feed and ME conversion rate were improved when lysine : ME ratio increased from 0.34 to 0.50, whereby all parameters showed a significant ratio x sex interaction. Feed intake and feed conversion rate were higher at a dietary energy density of 13 MJ ME than at an energy density of 14 MJ ME but energy density did not influence daily growth rate, ME intake and ME conversion rate. Fat area above eye muscle and meat : fat ratio were lower and eye muscle area and lean percentage were higher at a ratio of 0.42 compared with a ratio of 0.34. Daily feed intake, body weight gain, feed conversion rate and parameters of fatness were higher in barrows than in gilts. Conversely, gilts had higher eye muscle area and lean percentage. Optimum ratio for body weight gain, feed and ME conversion rate calculated by exponential regression analysis were 0.42-0.43 in barrows. In gilts, feed and ME conversion rate were optimized at a ratio of 0.53 and 0.54. Because growth showed a linear response to increasing digestible lysine : ME ratios, optimum ratio for daily gain in gilts is considered to be at least 0.58.

Animal Feed↗

Conversion of total leaf area to projected leaf area in lodgepole pine and Douglas-fir.

Three definitions of leaf area index (LAI) in the literature have no predictable relationship with each other. Factors were derived for converting total LAI to projected LAI of horizontal leaves and to projected LAI for inclined leaves of lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) and coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) to allow comparison of results from different studies. An algorithm was derived to allow determination of these factors based on twig angles and the angles that the foliage subtends with the twig. Allowances were made for both the vertical and horizontal components of projection. The value of the factor for converting total LAI to projected LAI for inclined leaves was 0.229 + 0.0032 for lodgepole pine and 0.230 + 0.0037 for Douglas-fir. Sensitivity analysis established that this conversion factor was more sensitive to differences in vertical angles of the twigs than to twig rotation or foliar arrangement on the twig.

Journal Article↗

Setting the agenda: an analysis of negotiation strategies in clinical talk.

This article analyzes the process whereby physicians and patients set the agenda for medical interviews. Applying a conversation analytic perspective to the analysis of 22 videotapes of primary care interviews at a large, urban, teaching and research hospital, a 3-stage model is developed, consisting of (a) an opening sequence, (b) an initial statement of concerns by the patient, and (c) the negotiation process. The analysis illustrates the critical function of the opening verbal exchanges, showing how patient responses to the physician's first question and subsequent queries and summaries by the physician are intricately interwoven. The interaction at the very beginning of the interview is shown to significantly alter the ensuing interaction. The analysis provides a discursive framework for analyzing problematic communication during the primary care interview.

Communication↗

Routine two-step skin testing for tuberculosis in the staff of a geriatric hospital in Israel: booster and conversion rates.

The objective of this study was to determine the prevalence of positive skin tests amongst the staff of a 200 bed geriatric hospital in Haifa, Israel. By comparing the findings with those of a study performed five years previously, we hoped to ascertain the number of conversions which had occurred in the period studied. This was undertaken in order to assess a new policy from the Israel Ministry of Health regarding skin testing for health care workers. We also hoped to decide upon the frequency of skin testing required and to compare data from recent immigrants from countries with a high prevalence of TB. In 1997, we performed two-step skin testing (TSST) on 318 health care workers. We ascertained the number of positive reactions on the first and second testing and calculated the number of subjects who showed significant boosting. We also compared the results to those obtained in a study in 1992 and calculated the rate of conversion. We used multivariate analysis to examine the effects of age, gender, country of origin, years in Israel, previous BCG vaccination, previous exposure to contagious TB, work site and area of residence in the city, on the response to TSST. Between 1990 and 1996, 655 000 immigrants from the former USSR arrived; 'recent immigration' was defined from that date onward. The final number of positive reactions out of 282 subjects, who were either positive or negative on step 1 and presented for step 2, was 171 (60%). Booster effect was not significantly associated with any of the variables examined. The size of reaction in TSST was related to country of origin and recent immigration. The 83 recent immigrants from the former USSR had more frequent (61%) and larger reactions (mean (sd): 9.0 (6.46) mm) than the 114 native-born Israelis with 39% positive reactions (6.2 (5.89) P= 0.009). Comparison with 1992 revealed 26 (31%) of previous negatives as positive. Conversion was associated with age. All conversions save one were in individuals younger than 50 years (P= 0.07). In conclusion, TSST, performed to enable detection of recent infection after exposure to contagious TB, was relevant for 40% of health care workers (HCWs). Second step testing contributed an additional 23% positive reactions. New immigrants had larger initial reactions. Conversion occurred mostly in younger workers and could be either due to unrecognized TB in the hospital or to exposure in the community.

Adult↗

Lamotrigine analysis in plasma by gas chromatography-mass spectrometry after conversion to a tert.-butyldimethylsilyl derivative.

Lamotrigine (lamictal) is a new anticonvulsant drug recently approved by the FDA for clinical use. Therapeutic monitoring of lamotrigine is useful for patient management (therapeutic range 1-4 microg/ml). Here we describe a gas chromatography-mass spectrometric identification and quantitation of lamotrigine after extraction from human serum and derivatization. Lamotrigine was extracted from alkaline serum with chloroform and derivatized with N-methyl-N-(tert.-butyldimethysilyl) trifluoroacetamide containing 2% tert.-butyldimethylchlorosilane. Oxazepam-d5 was used as an internal standard. The tert.-butyldimethylsilyl derivative of lamotrigine showed distinct molecular ions at m/z 483 and 485 as well as other peaks at m/z 426, 370 and 334 for unambiguous identification. The base peak was observed at m/z 199. Similarly, the tert.-butyldimethysilyl derivative of oxazepam-d5 showed molecular ions at m/z 519 and 521 along with other characteristic peaks at m/z 462, 376 and 318. For the analysis of lamotrigine, the mass spectrometer was operated in the selective ion monitoring mode. The within-run and between-run precisions were 4.3% (mean=3.01, S.D.=0.13 microg/ml) and 5.1% (mean=2.93, S.D.=0.15 microg/ml), respectively at a serum lamotrigine concentration of 3.0 microg/ml. The within-run and between-run precisions were 8.2% (mean=0.49, S.D.=0.04 microg/ml) and 10.6% (mean=0.47, S.D.=0.05 microg/ml), respectively at a serum lamotrigine concentration of 0.5 microg/ml. The assay was linear for serum lamotrigine concentrations of 0.5-20 microg/ml. The detection limit was 0.25 microg/ml. The assay was free from interferences from common tricyclic antidepressants, benzodiazepines, other common anticonvulsants, salicylate and acetaminophen.

Anticonvulsants↗

B-scanning evaluation with image analysis of psoriatic skin.

Ten psoriatic plaques from different subjects were investigated by 20 MHz ultrasound B scanning. Lesions were evaluated before therapy, and after 7 and 15 days of topical treatment with anthralin. Recordings from lesional skin were compared with those from clinically non-involved contralateral skin. Images were assessed by means of a new image analysis program, allowing the conversion of the B-scan image color scale into a numerical amplitude scale, the selection and highlighting of amplitude bands, and the quantification of objects reflecting in a definite amplitude range. B-scanning evaluation of the psoriatic plaque revealed a thickening of the epidermis and dermis, the presence of parallel acoustic shadows in the dermis, and a characteristic hypo-echogenic band corresponding to the papillary dermis. Image processing allowed an exact quantification of the progressive reduction in thickness of the epidermis and dermis and of the hypo-echogenic band observed at skin sites which had been treated with topical substances. Thus, the echographic method with image analysis allows the evaluation of three different parameters of response to topical treatment of psoriatic skin.

Adult↗

Methylglyoxal in beverages and foods: its mutagenicity and carcinogenicity.

Methylglyoxal was found to induce mutations in Salmonella typhimurium strains TA100, TA102 and TA104, gene conversion in Saccharomyces cerevisiae strain D7, and diphtheria toxin resistance mutation in Chinese hamster lung cells. Methylglyoxal was detected in coffee, whiskey, a soft drink, toasted bread and soy sauce. The mutagenicity of methylglyoxal was suppressed by sulfite, cysteine, glutathione and dithiothreitol, and enhanced by hydrogen peroxide. Methylglyoxal induced sarcomas in rats at the site of its subcutaneous injection.

Aldehydes↗

Applications of high-performance liquid chromatography to quantitation of metabolites and enzymes of the patulin pathway from Penicillium patulum.

Conditions for extraction and high-performance liquid chromatographic (HPLC) analysis for fourteen of the patulin pathway metabolites from Penicillium patulum are described which allow quantitation of the metabolite content of cultures at hourly intervals. The HPLC analysis is more sensitive than gas-liquid chromatographic analysis and is more quantitative than thin-layer chromatographic analysis. Separations on a preparative column allow for the collection and identification of new metabolites. The column elution program can be varied to optimize analysis time for individual metabolites, allowing individual enzymes of the pathway to be assayed by following the conversion of substrate to product. Analysis of product formation in crude enzyme mixtures can be used to assay an enzyme in the presence of subsequent enzymes of the pathway and to establish the pathway reaction sequence.

Chromatography, High Pressure Liquid↗

Gene conversion between unlinked sequences in the germline of mice.

Gene conversion between homologous sequences on non-homologous chromosomes (ectopic gene conversion) is remarkably frequent in fungi. It is thought to be a consequence of genome-wide homology scanning required to form synapses between homologous chromosomes. This activity provides a mechanism for concerted evolution of dispersed genes. Technical obstacles associated with mammalian systems have hitherto precluded investigations into ectopic gene conversion in the mammals. Here, we describe a binary transgenic mouse system to detect ectopic gene conversion in mice. Conversion events are visualized by histochemical staining of spermatids, and corroborated by polymerase chain reaction amplification of transgenes in spermatozoa. The results show that conversion between unliked, hemizygous lacZ transgenes is frequent in the male germline, ranging from 0.1 to 0.7% of spermatids. Genomic location may affect the susceptibility to recombination, since the frequency varied between lines. The results suggest that homologous genes can undergo concerted evolution despite being genomically dispersed. However, mechanisms may exist to modulate this activity, enabling the divergence of duplicated genes.

Animals↗

Role of flow dispersion in the computation of microvascular flows by the dual-slit method.

Microvascular blood flow is commonly calculated from a "centerline" velocity derived from the dual-slit method. This is done by relating the computed centerline velocity to an average velocity through an empirically derived conversion factor. To determine the physical basis of the conversion factor, we utilized a Fourier transform and indicator dilution theory to model the parameters governing the conversion factor. We assumed Poiseuille flow from slit 1 to 2 and that the signals from the two slits were sinusoidal functions. Under these conditions, the conversion factor was found to depend primarily on a dimensionless time which is the product of the frequency of the sinusoidal signals and their time delay. Theory shows that if this dimensionless time is in the range of 3 to 7, the conversion factor lies within 1.5 to 1.7. Analysis of original dual-slit samples showed the conversion factor, obtained from the data of five arterioles and three venules, to be 1.58 +/- 0.03, and independent of the microvessel diameter.

Animals↗