921 resultados para Readings and recitations.


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INTRODUCTION: Therapeutic hypothermia (TH) is often used to treat out-of-hospital cardiac arrest (OHCA) patients who also often simultaneously receive insulin for stress-induced hyperglycaemia. However, the impact of TH on systemic metabolism and insulin resistance in critical illness is unknown. This study analyses the impact of TH on metabolism, including the evolution of insulin sensitivity (SI) and its variability, in patients with coma after OHCA. METHODS: This study uses a clinically validated, model-based measure of SI. Insulin sensitivity was identified hourly using retrospective data from 200 post-cardiac arrest patients (8,522 hours) treated with TH, shortly after admission to the intensive care unit (ICU). Blood glucose and body temperature readings were taken every one to two hours. Data were divided into three periods: 1) cool (T <35°C); 2) an idle period of two hours as normothermia was re-established; and 3) warm (T >37°C). A maximum of 24 hours each for the cool and warm periods was considered. The impact of each condition on SI is analysed per cohort and per patient for both level and hour-to-hour variability, between periods and in six-hour blocks. RESULTS: Cohort and per-patient median SI levels increase consistently by 35% to 70% and 26% to 59% (P <0.001) respectively from cool to warm. Conversely, cohort and per-patient SI variability decreased by 11.1% to 33.6% (P <0.001) for the first 12 hours of treatment. However, SI variability increases between the 18th and 30th hours over the cool to warm transition, before continuing to decrease afterward. CONCLUSIONS: OCHA patients treated with TH have significantly lower and more variable SI during the cool period, compared to the later warm period. As treatment continues, SI level rises, and variability decreases consistently except for a large, significant increase during the cool to warm transition. These results demonstrate increased resistance to insulin during mild induced hypothermia. Our study might have important implications for glycaemic control during targeted temperature management.

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A direct agglutination test (DAT) and an immunofluorescence technique (IFAT) were compared for detection of Leishmania infantum infection in 43 dogs and five foxes from Alto-Douro and Arrábida, two known endemic areas in Portugal. In four dogs with proved canine leishmaniasis, both DAT and IFAT showed positive readings (titres >1:320 and >1:128). Of 34 samples collected from apparently healthy dogs, ten were positive by both serological tests and eight were serologically positive by one test or the other. Three foxes out of five captured in this area, scored titres indicative of leishmaniasis in both DAT and IFAT. The concordance between DAT and IFAT in all collected samples (48) was 81.25%. Considering these and previous studies in the adjacent Mediterranean areas, the seroprevalence of L. infantum infection in the canine and vulpine populations appear to be of high magnitude.

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BACKGROUND AND AIMS: little is known regarding the reproducibility of body fat measuring devices; hence, we assessed the between and within-device reproducibility, and the within-day variability of body fat measurements. METHODS: body fat percentage was measured twice on seventeen female students aged between 18 and 20 with a body mass index of 21.9 ± 2.5 kg/m2 (mean ± SD) using seven bipolar bioelectrical impedance devices. Each participant was also measured each hour between 7:00 and 22:00. RESULTS: the correlation between first and second measurements was very high (Spearman r between 0.985 and 1.000, p<0.001), as well as between devices (Spearman r between 0.916 and 0.991, p<0.001). Repeated measurements analysis showed no differences were between devices (p=0.59) or readings (first vs. second: p=0.74). Conversely, significant differences were found between assessment periods throughout the day, measurements made in the morning being lower than those made in the afternoon (F test for repeated values= 6.58, p<0.001). CONCLUSIONS: the between and within-device reproducibility for measuring body fat is high, enabling the use of multiple devices in a single study. Conversely, small but significant changes in body fat measurements occur during the day, urging body fat measurements to be performed at fixed times.

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Objective: to assess the between and within-device reproducibility, as well as within-day variability of body fat measurements. Methods: body fat percentage (%BF) was measured twice on seventeen female students aged between 18 and 20 with a body mass index of 21.9 22.6 kg/m2 (mean SD) using seven bipolar bioelectrical impedance devices (BF-306) according to the manufacturer's recommendations. Each student was also measured each hour between 7:00 and 22:00. Statistical analysis was conducted using a general linear model for repeated measurements. Results: the correlation between first and second measurements was very high (Pearson r between 0.985 and 1.000, p<0.001), as well as the correlation between devices (Pearson r between 0.986 and 0.999, all p<0.001). Repeated measurements analysis showed no differences were between devices (F test=0.83, p=0.59) or readings (first vs. second: F test=0.12, p=0.74). Conversely, significant differences were found between assessment periods throughout the day, measurements made in the morning being lower than those made in the afternoon. Assuming an overall daily average of 100 (based on all measurements), the values were 95.8 3.2 (mean SD) at 8:00 versus 101.3 3.0 at 20:00, corresponding to a mean change of 2.2 1.1 in %BF (F test for repeated values=6.58, p<0.001). Conclusions: the between and within-device reproducibility for measuring body fat is high, enabling the use of multiple devices in a single study. Conversely, small but significant changes in body fat measurements occur during the day, urging body fat measurements to be performed at fixed times.

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BACKGROUND Skin patch test is the gold standard method in diagnosing contact allergy. Although used for more than 100 years, the patch test procedure is performed with variability around the world. A number of factors can influence the test results, namely the quality of reagents used, the timing of the application, the patch test series (allergens/haptens) that have been used for testing, the appropriate interpretation of the skin reactions or the evaluation of the patient's benefit. METHODS We performed an Internet -based survey with 38 questions covering the educational background of respondents, patch test methods and interpretation. The questionnaire was distributed among all representatives of national member societies of the World Allergy Organization (WAO), and the WAO Junior Members Group. RESULTS One hundred sixty-nine completed surveys were received from 47 countries. The majority of participants had more than 5 years of clinical practice (61 %) and routinely carried out patch tests (70 %). Both allergists and dermatologists were responsible for carrying out the patch tests. We could observe the use of many different guidelines regardless the geographical distribution. The use of home-made preparations was indicated by 47 % of participants and 73 % of the respondents performed 2 or 3 readings. Most of the responders indicated having patients with adverse reactions, including erythroderma (12 %); however, only 30 % of members completed a consent form before conducting the patch test. DISCUSSION The heterogeneity of patch test practices may be influenced by the level of awareness of clinical guidelines, different training backgrounds, accessibility to various types of devices, the patch test series (allergens/haptens) used for testing, type of clinical practice (public or private practice, clinical or research-based institution), infrastructure availability, financial/commercial implications and regulations among others. CONCLUSION There is a lack of a worldwide homogeneity of patch test procedures, and this raises concerns about the need for standardization and harmonization of this important diagnostic procedure.

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The clinical demand for a device to monitor Blood Pressure (BP) in ambulatory scenarios with minimal use of inflation cuffs is increasing. Based on the so-called Pulse Wave Velocity (PWV) principle, this paper introduces and evaluates a novel concept of BP monitor that can be fully integrated within a chest sensor. After a preliminary calibration, the sensor provides non-occlusive beat-by-beat estimations of Mean Arterial Pressure (MAP) by measuring the Pulse Transit Time (PTT) of arterial pressure pulses travelling from the ascending aorta towards the subcutaneous vasculature of the chest. In a cohort of 15 healthy male subjects, a total of 462 simultaneous readings consisting of reference MAP and chest PTT were acquired. Each subject was recorded at three different days: D, D+3 and D+14. Overall, the implemented protocol induced MAP values to range from 80 ± 6 mmHg in baseline, to 107 ± 9 mmHg during isometric handgrip maneuvers. Agreement between reference and chest-sensor MAP values was tested by using intraclass correlation coefficient (ICC = 0.78) and Bland-Altman analysis (mean error = 0.7 mmHg, standard deviation = 5.1 mmHg). The cumulative percentage of MAP values provided by the chest sensor falling within a range of ±5 mmHg compared to reference MAP readings was of 70%, within ±10 mmHg was of 91%, and within ±15mmHg was of 98%. These results point at the fact that the chest sensor complies with the British Hypertension Society (BHS) requirements of Grade A BP monitors, when applied to MAP readings. Grade A performance was maintained even two weeks after having performed the initial subject-dependent calibration. In conclusion, this paper introduces a sensor and a calibration strategy to perform MAP measurements at the chest. The encouraging performance of the presented technique paves the way towards an ambulatory-compliant, continuous and non-occlusive BP monitoring system.

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In this study we determine whether blood pressure readings using a cuff of fixed size systematically differed from readings made with a triple-bladder cuff (Tricuff) that automatically adjusts bladder width to arm circumference and assessed subsequent clinical and epidemiological effects. Blood pressure was measured with a standard cuff or a Tricuff in 454 patients visiting an outpatient clinic in the Seychelles (Indian Ocean). Overall means of within-individual standard cuff-Tricuff differences in systolic and diastolic blood pressures were examined in relation to arm circumference and sex. The standard cuff-Tricuff difference in systolic and diastolic blood pressures increased monotonically with circumference (from 4.7 +/- 0.8/3.2 +/- 0.7 mm Hg for arm circumference of 30 to 31 cm to 10.0 +/- 1.1/8.0 +/- 0.9 mm Hg for arm circumference &gt; or = 36 cm) and was larger in women than men. Multivariate linear regression indicated independent effects of arm circumference and sex. Forty percent of subjects with a diastolic blood pressure of &gt; or = 95 mm Hg measured with a standard cuff had values less than 95 mm Hg measured with a Tricuff. Extrapolation to the entire population of the Seychelles decreased the prevalence of blood pressure greater than or equal to 160/95 mm Hg by 11.5% and 24.0% in men and women, respectively, aged 35 to 64 years. The age-adjusted effect of body mass index on systolic and diastolic blood pressures decreased twofold using blood pressure readings made with a Tricuff instead of a standard cuff.(ABSTRACT TRUNCATED AT 250 WORDS)

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Goals: Adjuvant chemotherapy decisions in breast cancer are increasing based on the pathologist's assessment of the proliferation fraction in the tumor. Yet, how good and how reproducible are we pathologists at providing reliable Ki-67 readings on breast carcinomas. Exactly how to count and in which areas to count within a tumor remains inadequately standardized. The Swiss Working Group of Gyneco- and Breast Pathologists has tried to appreciate this dilemma and to propose ways to obtain more reproducible results.Methods: In a first phase, 5 pathologists evaluated Ki67 counts in 10 breast cancers by exact counting (500 cells) and by eyeballing. Pathologists were free to select the region in which Ki67 was evaluated. In a second phase 16 pathologists evaluated Ki-67 counts in 3 breast cancers also by exact counting and eyeballing, but in predefined fields of interest. In both phases, Ki67 was assessed in centrally immunostained slides (ZH) and on slides immunostained in the 11 participating laboratories. In a third phase, these same 16 pathologists were once again asked to read the 3 cases from phase 2, plus three new cases, and this time exact guidelines were provided as to what exactly is considered a Ki-67 positive nucleus.Results: Discordance of Ki67 assessment was due to each of the following 4 factors: (i) pathologists' divergent definitions of what counts as a positive nucleus (ii) the mode of assessment (counting vs. eyeballing), (iii) immunostaining technique/protocol/antibody, and (iv) the selection of the area in which to count.Conclusion: Providing guidelines as to where to count (representative field in the tumor periphery and omitting hot spots) and what nuclei to count (even faintly immunostained nuclei count as positive) reduces the discordance rates of Ki67 readings between pathologists. Laboratory technique is only of minor importance (even over a large antibody dilution range), and counting nuclei does not improve accuracy, but rather aggravates deviations from the group mean values.Disclosure of Interest: None Declared

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Soil moisture is the property which most greatly influences the soil dielectric constant, which is also influenced by soil mineralogy. The aim of this study was to determine mathematical models for soil moisture and the dielectric constant (Ka) for a Hapludalf, two clayey Hapludox and a very clayey Hapludox and test the reliability of universal models, such as those proposed by Topp and Ledieu and their co-workers in the 80's, and specific models to estimate soil moisture with a TDR. Soil samples were collected from the 0 to 0.30 m layer, sieved through a mesh of 0.002 m diameter and packed in PVC cylinders with a 0.1 m diameter and 0.3 m height. Seven samples of each soil class were saturated by capillarity and a probe composed of two rods was inserted in each one of them. Moisture readings began with the saturated soil and concluded when the soil was near permanent wilting point. In each step, the samples were weighed on a precision scale to calculate volumetric moisture. Linear and polynomial models were adjusted for each soil class and for all soils together between soil moisture and the dielectric constant. Accuracy of the models was evaluated by the coefficient of determination, the standard error of estimate and the 1:1 line. The models proposed by Topp and Ledieu and their co-workers were not adequate for estimating the moisture in the soil classes studied. The adjusted linear and polynomial models for the entire set of data of the four soil classes did not have sufficient accuracy for estimating soil moisture. The greater the soil clay and Fe oxide content, the greater the dielectric constant of the medium for a given volumetric moisture. The specific models, θ = 0.40283 - 0.04231 Ka + 0.00194 Ka² - 0.000022 Ka³ (Hapludox) θ = 0.01971 + 0.02902 Ka - 0.00086 Ka² + 0.000012 Ka³ (Hapludox -PF), θ = 0.01692 - 0.00507 Ka (Hapludalf) and θ = 0.08471 + 0.01145 Ka (Hapludox-CA), show greater accuracy and reliability for estimating soil moisture in the soil classes studied.

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INTRODUCTION: Auscultatory nonmercury manual devices seem good alternatives for the mercury sphygmomanometers in the clinic and for research settings, but individual internal validation of each device is time-consuming. The aim of this study was to validate a new technique capable of testing two devices simultaneously, based on the International protocol of the European Society of Hypertension. METHODS: The concept of the new technique is to measure blood pressure alternatively by two observers using a mercury sphygmomanometer and by two observers using the A&D UM-101 and Accoson Greenlight 300 devices, connected by Y-tube to obtain simultaneous readings with both nonmercury devices. Thirty-three participants were enrolled (mean age 47.2±14.0 years). Nine sequential blood pressure measurements were performed for each participant. RESULTS: Both devices passed phase 1 using 15 participants. In phase 2.1 (n=33), on a maximum of 99 measurements, the Accoson device produced 81/95/99 measurements within 5/10/15 mmHg for systolic blood pressure (SBP) and 87/98/99 for diastolic blood pressure (DBP). The A&D device produced 86/96/99 for SBP and 94/99/99 for DBP. In phase 2.2 (n=33), 30 participants had at least 2 out of 3 SBP obtained with Accoson device within 5 mmHg of the mercury device, as compared with 29 of 33 participants with the A&D device. For DBP, this was 33 of 33 participants for both devices. CONCLUSION: Both the nonmercury devices passed the International protocol. The new technique of simultaneous device testing using a Y-tube represents a time saving application of the International protocol.

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The use of leaf total nitrogen concentration as an indicator for nutritional diagnosis has some limitations. The objective of this study was to determine the reliability of total N concentration as an indicator of N status for eucalyptus clones, and to compare it with alternative indicators. A greenhouse experiment was carried out in a randomized complete block design in a 2 × 6 factorial arrangement with plantlets of two eucalyptus clones (140 days old) and six levels of N in the nutrient solution. In addition, a field experiment was carried out in a completely randomized design in a 2 × 2 × 2 × 3 factorial arrangement, consisting of two seasons, two regions, two young clones (approximately two years old), and three positions of crown leaf sampling. The field areas (regions) had contrasting soil physical and chemical properties, and their soil contents for total N, NH+4-N, and NO−3-N were determined in five soil layers, up to a depth of 1.0 m. We evaluated the following indicators of plant N status in roots and leaves: contents of total N, NH+4-N, NO−3-N, and chlorophyll; N/P ratio; and chlorophyll meter readings on the leaves. Ammonium (root) and NO−3-N (root and leaf) efficiently predicted N requirements for eucalyptus plantlets in the greenhouse. Similarly, leaf N/P, chlorophyll values, and chlorophyll meter readings provided good results in the greenhouse. However, leaf N/P did not reflect the soil N status, and the use of the chlorophyll meter could not be generalized for different genotypes. Leaf total N concentration is not an ideal indicator, but it and the chlorophyll levels best represent the soil N status for young eucalyptus clones under field conditions.

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Self-measurement of blood pressure (SMBP) is increasingly used to assess blood pressure outside the medical setting. A prerequisite for the wide use of SMBP is the availability of validated devices providing reliable readings when they are handled by patients. This is the case today with a number of fully automated oscillometric apparatuses. A major advantage of SMBP is the great number of readings, which is linked with high reproducibility. Given these advantages, one of the major indications for SMBP is the need for evaluation of antihypertensive treatment, either for individual patients in everyday practice or in clinical trials intended to characterize the effects of blood-pressure-lowering medications. In fact, SMBP is particularly helpful for evaluating resistant hypertension and detecting white-coat effect in patients exhibiting high office blood pressure under antihypertensive therapy. SMBP might also motivate the patient and improve his or her adherence to long-term treatment. Moreover, SMBP can be used as a sensitive technique for evaluating the effect of antihypertensive drugs in clinical trials; it increases the power of comparative trials, allowing one to study fewer patients or to detect smaller differences in blood pressure than would be possible with the office measurement. Therefore, SMBP can be regarded as a valuable technique for the follow-up of treated patients as well as for the assessment of antihypertensive drugs in clinical trials.

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This paper evaluates the reception of Léon Walras' ideas in Russia before 1920. Despite an unfavourable institutional context, Walras was read by Russian economists. On the one hand, Bortkiewicz and Winiarski, who lived outside Russia and had the opportunity to meet and correspond with Walras, were first class readers and very good ambassadors for Walras' ideas, while on the other, the economists living in Russia were more selective in their readings. They restricted themselves to Walras' Elements of Pure Economics, in particular, its theory of exchange, while ignoring its theory of production. We introduce a cultural argument to explain their selective reading. JEL classification numbers: B 13, B 19.

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In line with educational issues involved in emergent literacy practices in preschool, in particular those concerning comprehension processes, this paper focuses on picture-based narrative comprehension during an interactive reading session of a wordless picture book, involving a group of children aged three and their teacher. Children are asked to make inferences about the meaning and outcome of the story, a procedure which gradually elicits their responses on how events link together, thus enhancing their capacity to use prior and implicit knowledge to build the story meaning. Moreover, this study highlights the importance of interaction for developing comprehension. Data collected was analysed following didactic microgenesis, an analytical approach showing that knowledge built during interaction depends on the joint construction of a zone of common meaning by which teacher and children try to adjust to each other. In order to help the process of merging different meanings of the story built online, a text written by researchers, following the narrative structure of the story, was read by the teacher after the picture-based reading. This led us to examine through interactional analysis which semiotic cues were used during recall on the following day, as an additional measure of knowledge construction.