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1.
Talanta ; 226: 122185, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33676716

RESUMEN

A new and fully automated system with the interconnection of an Optical Immersion Probe (OIP) - pH meter - peristaltic pump was used to study the spectral and protolytic properties of carbocyanine the dyes 1,1',3,3,3',3'-hexamethylindocarbocyanine chloride (HIC); 1,1',3,3,3',3'-hexamethylindodicarbocyanine iodide (HIDC); and 3,3'-diethyloxadicarbocyanine iodide (DODC). This system can measure a large number of experimental points in a short time period. The effect of 32 various organic solvents on the UV-ViS spectra of the dyes was studied. The solvatochromic behaviour of studied dyes was characterized by positive solvatochromism for HIDC and negative solvatochromism for HIC and DODC. Through the application of a large number of experimental points, the protonation and hydrolysis constants of dyes were determined with high precision, where the confidence interval of the рK values is ±(0.001-0.005), compared with a confidence interval of ±(0.04-0.10) for standard procedures. The fully automated system presented is accurate, fast, environmentally friendly and promising for multiple analytical applications.

2.
Allergol. immunopatol ; 45(5): 487-495, sept.-oct. 2017. tab
Artículo en Inglés | IBECS | ID: ibc-167004

RESUMEN

Background: Few data are available concerning the time trends and risk factors associated with allergic rhinitis (AR) in schoolchildren in Hungary. Methods: At an interval of six years, parents of 6–12-year-old children completed identical ISAAC-based and additional questionnaires related to possible risk factors. Results: Response rate was 62.8% with 6335 questionnaires distributed in 2007, and 52.9% with 6441 questionnaires in 2013. The prevalence of current AR symptoms (subjects presenting clinical symptoms of AR in the past 12 months, but had yet to be diagnosed by physician) increased significantly from 14.9% to 23.5% (p < 0.001). There was no significant change in the prevalence of physician-diagnosed AR (11.6–11.2%). In multivariate analysis, gender (OR 0.733; CI 0.642–0.931), a family history of atopy (OR 2.017; CI 1.669–2.436), frequent upper respiratory tract infections (OR 2.033; CI 1.659–2.492), long-lasting disease before the appearance of the allergy (OR 2.119; CI 1.311–3.428), feather bedding (OR 0.773; CI 0.599–0.996) and living in a green area (OR 1.367; CI 1.133–1.650) were found to be significant risk factors of cumulative AR in 2013. In both of the groups with (p < 0.000) or without (p < 0.003) AR the families with a history of atopy used feather bedding less frequently than families without atopy. Conclusion: Although the prevalence of physician-diagnosed AR has not shown significant changes during the studied interval, the significant increase of the current AR symptoms suggests growing prevalence of AR among children in Budapest. Our results revealed new aspects of bedding customs in atopic families (AU)


No disponible


Asunto(s)
Humanos , Masculino , Femenino , Niño , Rinitis Alérgica/epidemiología , Polvo/análisis , Asma/epidemiología , Hipersensibilidad Inmediata/epidemiología , Factores de Riesgo , Prevalencia , Encuestas y Cuestionarios , Enfermedades Genéticas Congénitas/epidemiología , Ácaros/patogenicidad , Ropa de Cama y Ropa Blanca/microbiología , Estudios Transversales
3.
Allergol Immunopathol (Madr) ; 45(5): 487-495, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28629670

RESUMEN

BACKGROUND: Few data are available concerning the time trends and risk factors associated with allergic rhinitis (AR) in schoolchildren in Hungary. METHODS: At an interval of six years, parents of 6-12-year-old children completed identical ISAAC-based and additional questionnaires related to possible risk factors. RESULTS: Response rate was 62.8% with 6335 questionnaires distributed in 2007, and 52.9% with 6441 questionnaires in 2013. The prevalence of current AR symptoms (subjects presenting clinical symptoms of AR in the past 12 months, but had yet to be diagnosed by physician) increased significantly from 14.9% to 23.5% (p<0.001). There was no significant change in the prevalence of physician-diagnosed AR (11.6-11.2%). In multivariate analysis, gender (OR 0.733; CI 0.642-0.931), a family history of atopy (OR 2.017; CI 1.669-2.436), frequent upper respiratory tract infections (OR 2.033; CI 1.659-2.492), long-lasting disease before the appearance of the allergy (OR 2.119; CI 1.311-3.428), feather bedding (OR 0.773; CI 0.599-0.996) and living in a green area (OR 1.367; CI 1.133-1.650) were found to be significant risk factors of cumulative AR in 2013. In both of the groups with (p<0.000) or without (p<0.003) AR the families with a history of atopy used feather bedding less frequently than families without atopy. CONCLUSION: Although the prevalence of physician-diagnosed AR has not shown significant changes during the studied interval, the significant increase of the current AR symptoms suggests growing prevalence of AR among children in Budapest. Our results revealed new aspects of bedding customs in atopic families.


Asunto(s)
Población , Rinitis Alérgica/epidemiología , Factores de Tiempo , Ropa de Cama y Ropa Blanca , Niño , Estudios Transversales , Familia , Femenino , Hábitos , Humanos , Masculino , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Población Urbana
4.
Appl Ergon ; 53 Pt A: 143-51, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26464034

RESUMEN

We have evaluated the consequences of work organization on musculoskeletal health. Using a postal questionnaire, answered by 1600 female grocery store workers, their main work tasks were identified and four work groups were defined (cashier, picking, and delicatessen work, and a mixed group, who performed a mix of these tasks). The crude odds ratios (ORs) for neck/shoulder complaints were 1.5 (95% CI 1.0-2.2), 1.1 (0.7-1.5) and 1.6 (1.1-2.3), respectively, compared to mixed work. Adjusting for individual and psychosocial factors had no effect on these ORs. For elbows/hands, no significant differences were found. Technical measurements of the workload showed large differences between the work groups. Picking work was the most strenuous, while cashier work showed low loads. Quantitative measures of variation revealed for mixed work high between minutes variation and the highest between/within minutes variation. Combining work tasks with different physical exposure levels increases the variation and may reduce the risk of musculoskeletal complaints.


Asunto(s)
Comercio , Industria de Alimentos , Dolor de Cuello/epidemiología , Enfermedades Profesionales/epidemiología , Dolor de Hombro/epidemiología , Extremidad Superior/fisiología , Carga de Trabajo , Adolescente , Adulto , Anciano , Comercio/organización & administración , Electromiografía , Femenino , Industria de Alimentos/organización & administración , Fuerza de la Mano , Cabeza/fisiología , Humanos , Persona de Mediana Edad , Ocupaciones , Postura , Prevalencia , Músculos Superficiales de la Espalda/fisiología , Encuestas y Cuestionarios , Suecia/epidemiología , Flujo de Trabajo , Carga de Trabajo/psicología , Adulto Joven
5.
Pharmazie ; 69(6): 424-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24974575

RESUMEN

Niemann-Pick C1-like 1 protein (NPC1L1) plays a critical role in intestinal cholesterol absorption. Previous studies found that the NPC1L1 c.-133A > G SNP, but not other NPC1L1 SNPs, was associated with response to statin treatment and statin-ezetimibe combinations. To date effect of NPC1L1 c.-133A > G SNP on ezetimibe monotherapy has not been studied. Our objective was to examine whether SNP c.-133A > G at the NPC1L1 gene has effects on lipid levels and on the efficacy of 3, 6 and 12 months of 10 mg daily ezetimibe monotherapy in hyperlipidemic patients with statin induced adverse effects. One hundred and one type IIa and IIb hyperlipidemic patients (72 females, 29 males; age: 61.23 +/- 9.87 ys; BMI: 28.18 +/- 4.29 kg/m2) were enrolled. The genotype frequencies were conformed to Hardy-Weinberg equilibrium. We could not find significant differences in initial lipid levels between AA and AG + GG patients. While plasma levels of apolipoprotein A1 (ApoA1) did not significantly decrease after ezetimibe treatment (1.96; 3.39 and 2.74%) in AA patients, a significant elevation in ApoA1 levels has been found after treatment in AG + GG patients (9.15; 8.54 and 13.58%). The effect of NPC1L1 c.-133A > G on the ApoA1 levels was found significant (p < 0.05). Efficacy of treatment with ezetimibe on other plasma lipid parameters after 3, 6 or 12 months did not differ significantly. NPC1L1-133A > G SNP influences the ApoA1 response to ezetimibe monotherapy, therefore, may alter the effect of ezetimibe on the structure and function of the high-density lipoprotein particles.


Asunto(s)
Apolipoproteína A-I/genética , Azetidinas/uso terapéutico , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/genética , Proteínas de la Membrana/genética , Anciano , Anticolesterolemiantes/farmacología , Apolipoproteínas B/metabolismo , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Creatina Quinasa/metabolismo , Ezetimiba , Femenino , Genotipo , Humanos , Lípidos/sangre , Masculino , Proteínas de Transporte de Membrana , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Espectrofotometría Ultravioleta
7.
Scand J Rheumatol ; 43(2): 119-23, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24180222

RESUMEN

OBJECTIVES: The aim of this study was to investigate work status and associated factors in patients with early rheumatoid arthritis (RA), with the emphasis on shoulder function, work-related mechanical exposure, and activity limitations related to the shoulder-arm-hand. METHOD: Patients with early RA were provided with self-report questionnaires quantifying work-related mechanical exposure and activity limitations. Shoulder function (i.e. isometric muscle strength, shoulder-arm movement, and shoulder pain), hand-grip force, and number of tender and swollen joints were assessed. RESULTS: The study comprised 135 patients (103 women and 32 men), with a mean age of 48 (SD 9.6) years, a mean disease duration of 21 (SD 9.6) months, and a mean Disease Activity Score using 28 joint counts (DAS28) of 3.7 (SD 1.4). The majority (75.6%) were working full- or part-time. Work hours correlated with work-related mechanical exposure (rs = -0.34, p < 0.001) and with physical work load (rs = 0.26, p = 0.0036). Work hours also correlated with shoulder function, that is shoulder-arm movement (rs = 0.34, p < 0.0001), shoulder strength (rs = 0.25, p = 0.0032), and activity-induced shoulder pain (rs = -0.45, p < 0.0001). Significant correlations were found between work hours and hand-grip force (rs = 0.45, p < 0.0001), activity limitations related to the shoulder-arm-hand (using the Disabilities of the Arm, Shoulder and Hand Questionnaire, DASH) (rs = -0.61, p < 0.0001), and DAS28 (rs = -0.43, p < 0.0001). DASH was found to be the only significant (p < 0.001) variable to independently explain the ability of working full-time [odds ratio (OR) 0.40, 95% confidence interval (CI) 0.29-0.55 per 10 increments, area under the receiver operating characteristic (ROC) curve (AUC) 0.81, 95% CI 0.74-0.89]. CONCLUSIONS: Work status in early RA is associated with shoulder function and activity limitations related to the shoulder-arm-hand accentuated by work-related mechanical exposure.


Asunto(s)
Artritis Reumatoide/fisiopatología , Fenómenos Biomecánicos/fisiología , Evaluación de la Discapacidad , Actividad Motora/fisiología , Articulación del Hombro/fisiopatología , Evaluación de Capacidad de Trabajo , Adulto , Femenino , Fuerza de la Mano/fisiología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Dimensión del Dolor , Estudios Retrospectivos , Autoinforme , Encuestas y Cuestionarios
8.
Ergonomics ; 56(9): 1376-86, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23862657

RESUMEN

In recent decades, comprehensive rationalisations have been implemented in public dentistry in Sweden. How rationalisations affect working conditions, health and production from a long-term perspective has been poorly investigated. This study aims to analyse changes and associations in dentists' working conditions, health and productivity during a 5-year period. In 2003 and 2008, 65 dentists responded to questionnaires measuring work conditions and health. Treatment times for patients and productivity were tracked in electronic registers. Paired t-tests showed that the number of treated adult patients per dentist increased, and perceived physical working conditions improved while perceived work control and leadership deteriorated. Structural equation modelling showed that physical factors were important for health and productivity. When assessing risks in the work environment, there is a need to understand the interaction of effects on working conditions and health due to rationalisations so as to increase the sustainability of production systems. PRACTITIONER SUMMARY: Dentistry in Sweden has undergone considerable change. Questionnaire surveys with dentists, undertaken in 2003 and 2008, found that the present rationalisations resulted in improved perceived physical working conditions. Aspects of the psychosocial working environment had deteriorated, however. This is a concern as health and workability are important for workplace efficiency.


Asunto(s)
Odontología/organización & administración , Odontología/tendencias , Eficiencia , Estado de Salud , Sector Público , Adulto , Citas y Horarios , Femenino , Humanos , Liderazgo , Masculino , Persona de Mediana Edad , Dolor Musculoesquelético/etiología , Salud Laboral , Esfuerzo Físico , Autonomía Profesional , Ausencia por Enfermedad/tendencias , Encuestas y Cuestionarios , Suecia , Factores de Tiempo , Lugar de Trabajo/psicología
9.
Ergonomics ; 56(2): 303-13, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23419089

RESUMEN

Swedish dentistry has been exposed to frequent rationalisation initiatives during the last half century. Previous research has shown that rationalisation often results in increased risk of developing work-related musculoskeletal disorders, thus reducing sustainability in the production system. In this prospective study, we assessed mechanical exposures among Swedish dentists in relation to specific rationalisations of clinical dental work during a six-year period. Body postures and movements of 12 dentists were assessed by inclinometry synchronised to video recordings of their work. No rationalisation effects could be shown in terms of a reduction in non-value-adding work ('waste'), and at job level, no major differences in mechanical exposure could be shown between baseline and follow-up. CONCLUSION: The present rationalisation measures in dentistry do not seem to result in rationalisation at job level, but may potentially be more successful at the overall dental system level. PRACTITIONER SUMMARY: In contrast to many previous investigations of the mechanical exposure implications of rationalisation, the present rationalisation measures did not increase the level of risk for dentists. It is highlighted that all occupations involved in the production system should be investigated to assess production system sustainability.


Asunto(s)
Odontólogos , Programas Nacionales de Salud , Enfermedades Profesionales/etiología , Postura , Pautas de la Práctica en Odontología , Odontología en Salud Pública , Análisis y Desempeño de Tareas , Soporte de Peso , Acelerometría , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Enfermedades Profesionales/prevención & control , Estudios Prospectivos , Suecia , Estudios de Tiempo y Movimiento , Grabación de Cinta de Video
10.
Appl Ergon ; 43(4): 803-11, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22208356

RESUMEN

Physical workload was recorded by electromyography, inclinometry and goniometry for twelve female dental hygienists during authentic work. Their work was, in relation to other types of work, characterised by pronounced head flexion (90th percentile 46°), high loads on the forearm extensor muscles (90th percentile 23% and 18% of maximal EMG (MVE), for the right and left sides, respectively), average loads on trapezius muscles (90th percentile 15% and 14% MVE), average arm elevation (99th percentile 83° and 72°) and average wrist flexion and velocities (50th percentiles 17° of extension and 7.3°/s, for the right side). Manual scaling and machinery (use of ultrasonic scaling and hand-pieces) showed higher loads on the trapezius muscles, regarding muscular rest, as well as the 10th and 50th percentiles, than the other tasks, and for the forearm extensor muscles, an almost complete lack of muscular rest (0.1% time), and much higher loads regarding the 10th and 50th percentiles. Further, more pronounced head flexion and lower head and upper arm velocities were found, indicating more constrained postures for the neck and shoulders for the manual scaling and machinery. Use of ultrasonic scaler reduced the 50th percentile loads on the right forearm extensor muscles, but had no effect on the fraction of muscular rest and on the 10th percentile load. These findings are consistent with the high prevalences of musculoskeletal disorders among dental hygienists.


Asunto(s)
Atención Odontológica/efectos adversos , Raspado Dental/efectos adversos , Enfermedades Musculoesqueléticas/fisiopatología , Enfermedades Profesionales/fisiopatología , Adulto , Electromiografía , Femenino , Mano/fisiología , Humanos , Persona de Mediana Edad , Movimiento , Músculo Esquelético/fisiopatología , Enfermedades Musculoesqueléticas/etiología , Cuello/fisiología , Enfermedades Profesionales/etiología , Postura , Autoinforme , Hombro/fisiología , Estadísticas no Paramétricas , Carga de Trabajo , Muñeca/fisiología , Adulto Joven
11.
Mol Syndromol ; 3(5): 215-22, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23293579

RESUMEN

Smith-Lemli-Opitz (SLO) syndrome is an autosomal recessive disorder characterized by multiple congenital abnormalities and mental retardation. The condition is caused by the deficiency of 7-dehydrocholesterol reductase (DHCR7) which catalyzes the final step in cholesterol biosynthesis. Biochemical diagnosis is based on increased concentration of 7-dehydrocholesterol (7-DHC) in the patient serum. Both life expectancy and quality of life are severely affected by the disease. The estimated prevalence of SLO syndrome ranges between 1:20,000 and 1:40,000 among Caucasians. Although the mutational spectrum of the disease is wide, approximately 10 mutations are responsible for more than 80% of the cases. These mutations show a large interethnic variability. There are no mutation distribution data from Hungary to date. Thirteen patients were diagnosed with SLO syndrome in our laboratory. As first-line tests, serum 7-DHC and total cholesterol were measured and, in positive cases, molecular genetic analysis of the DHCR7 gene was performed. Complete genetic background of the disease could be identified in 12 cases. In 1 case only 1 mutation was detected in a heterozygote form. One patient was homozygous for the common splice site mutation c.964-1G>C, while all other patients were compound heterozygotes. One novel missense mutation, c.374A>G (p.Tyr125Cys) was identified.

12.
Scand J Immunol ; 75(2): 227-30, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21958324

RESUMEN

X-linked hyper-IgM syndrome (XHIGM) is a primary immunodeficiency disorder (PID) caused by mutation in the gene encoding the CD40 ligand (CD40L) expressed on activated T cells. Prenatal genotyping in carriers with twin pregnancies is more challenging than in women with singleton pregnancies. In addition, women with twin pregnancies may decide on selective termination for which the risk of loss of the healthy foetus may exceed 7%. We report here on a family affected by XHIGM. Diagnosis of the disease was made in a male patient as late as 33 years of age. After family screening, the sister of the proband conceived male twins in two consecutive pregnancies. In the first pregnancy, one of the male foetuses was hemizygous for the c.521A>G (Q174R) mutation in the CD40L gene. In the second pregnancy, ultrasound scan showed one foetus to have exencephaly and karyotyping revealed this foetus to have trisomy 18. Several options were discussed, but the parents decided on selective termination in both pregnancies. The interventions were successful in both cases, and the mother now has two healthy sons. This report demonstrates the way in which advanced technologies in molecular medicine and obstetric interventions may assist families with decisions about possible selective termination in case of life-threatening molecular or chromosomal disorders. Diagnosis of CD40L deficiency at the age of 33 years in the proband was striking and indicated that PIDs are still neglected as disease entities in the evaluation of patients with recurrent severe infectious diseases.


Asunto(s)
Ligando de CD40/deficiencia , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/diagnóstico , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/genética , Embarazo Gemelar/genética , Trisomía/diagnóstico , Trisomía/genética , Aborto Eugénico , Adulto , Ligando de CD40/genética , Ligando de CD40/inmunología , Cromosomas Humanos Par 18/genética , Cromosomas Humanos Par 18/inmunología , Diagnóstico Tardío , Femenino , Edad Gestacional , Humanos , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/inmunología , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/patología , Recién Nacido , Cariotipificación , Masculino , Mutación , Linaje , Embarazo , Embarazo Gemelar/inmunología , Diagnóstico Prenatal , Linfocitos T/inmunología , Linfocitos T/patología , Trisomía/inmunología , Trisomía/patología , Síndrome de la Trisomía 18
13.
Ergonomics ; 54(10): 953-60, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21973006

RESUMEN

The present study investigates the dental work in terms of time distribution and mechanical exposure in value-adding work (VAW) and non-VAW. Further rationalisation of dental work would typically involve an increase in the proportion of VAW. Information on mechanical exposure within the classes of VAW and non-VAW may be used to predict possible implications of rationalisation. Sixteen dentists were investigated. Using a data logger, postures and movements were continuously recorded for each subject during the 4 h of work, which included the 45 min of video recording. Time distribution and mechanical exposure for the six different work activities identified were evaluated from the video recordings, using a loss analysis technique. VAW, which comprised 54% of the total working time, generally implied significantly more constrained mechanical exposures as compared with non-VAW. The results suggest that future rationalisation of dental work, involving a reduction of non-VAW, may increase the risk of developing musculoskeletal disorders. Statement of Relevance: The present study illustrates the potential effects of rationalisation on biomechanical exposures for dentists. The results highlight the significance of integrating ergonomic issues into the rationalisation process in dentistry in addition to ordinary workstation and tool design improvements performed by ergonomists.


Asunto(s)
Fenómenos Biomecánicos , Odontología , Postura/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/etiología , Suecia , Análisis y Desempeño de Tareas , Factores de Tiempo
14.
J Electromyogr Kinesiol ; 19(5): 1005-12, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18760937

RESUMEN

Goniometry of the wrist is a feasible method for studying wrist movements in most hand-intensive work. The precision and accuracy of the method per se is good. For the knowledge on validity of field measurements, the size of imprecision is of importance. This study evaluated this condition during standardized circumstances. Six women performed three different hand-intensive work tasks: 'materials picking', 'light assembly', and 'heavy assembly', repeated during three different days. Variance components between-days (within subjects) and between-subjects were derived for positions (flexion/extension and deviation) and movements, including angular velocities, % of time with very low velocity (<1 degree /s), as well as repetitiveness. For positions, the average standard deviations in the three tasks were, both between-days and between-subjects, 3-4 degrees . For movements, the coefficients of variation of angular velocities were about 10% between-days, and could to a great part be explained by differences in work rate. Between-subjects variability was higher, 20-40%. The variability was larger at low velocities than at high ones. The precision of the measured positions was good, expressed as small between-days and between-subjects variability. For movements, the between-days variability was also small, while there was a larger between-subjects variability. The imprecision of goniometry is consequently lower and comparable with inclinometry but lower than for EMG.


Asunto(s)
Artrometría Articular/métodos , Artrometría Articular/normas , Medicina del Trabajo/métodos , Medicina del Trabajo/normas , Rango del Movimiento Articular/fisiología , Articulación de la Muñeca/fisiología , Adulto , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Suecia
15.
J Electromyogr Kinesiol ; 16(2): 125-36, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16102977

RESUMEN

For measuring the physical exposure/workload in studies of work-related musculoskeletal disorders, direct measurements are valuable. However, the between-days and between-subjects variability, as well as the precision of the method per se, are not well known. In a laboratory, six women performed three standardised assembly tasks, all of them repeated on three different days. Triaxial inclinometers were applied to the head, upper back and upper arms. Between-days (within subjects) and between-subjects (within tasks) variance components were derived for the 10th, 50th and 90th percentiles of the angular and the angular velocity distributions, and for the proportion of time spent in predefined angular sectors. For percentiles of the angular distributions, the average between-days variability was 3.4 degrees , and the between-subjects variability 4.0 degrees . For proportion of time spent in angular sectors, the variability depended on the percentage of time spent in the sector; the relative variability was scattered and large, on average 103% between days and 56% between subjects. For the angular velocity percentiles, the average between-days variability was 7.9%, and the average between-subjects variability was 22%. The contribution of the measurement procedure per se to the between-days variability, i.e., the imprecision of the method, was small: less than 2 degrees for angles and 3% for angular velocity.


Asunto(s)
Movimiento/fisiología , Cuello/fisiología , Postura/fisiología , Extremidad Superior/fisiología , Carga de Trabajo , Aceleración , Adulto , Fenómenos Biomecánicos , Femenino , Humanos , Persona de Mediana Edad
17.
Andrologia ; 37(1): 25-8, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15644059

RESUMEN

The authors summarize their experience in 75 in vitro fertilization cycles, where frozen-thawed testicular spermatozoa were used for intracytoplasmic sperm injection. In 32 cases, motile spermatozoa could be observed in the frozen-thawed sample. In 34 cases, motility could be induced by pentoxifylline and in nine cases immotile spermatozoa, selected with hypoosmotic swelling test, were used for fertilization. The fertilization rates obtained with motile and immotile spermatozoa (66.1% versus 52.3%) were not significantly different. Our data demonstrate that freezing of testicular spermatozoa opened new possibilities for the treatment of azoospermic men. The clinical pregnancy rate per embryo transfer (ET) (21.87%) was comparable with previous results use of fresh testicular spermatozoa (27.7%). The quality and number of transferred embryos had the most significant impact on the pregnancy rate. The fertilization rate and frequency distribution of good-quality embryos were lower in the case of immotile spermatozoa, and pregnancies were only achieved when motile spermatozoa had been used.


Asunto(s)
Inyecciones de Esperma Intracitoplasmáticas , Motilidad Espermática , Adulto , Criopreservación , Femenino , Fertilización , Congelación , Humanos , Masculino , Embarazo
18.
J Electromyogr Kinesiol ; 14(4): 443-54, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15165594

RESUMEN

Though surface electromyography (EMG) has been widely used in studies of occupational exposure, its precision in terms of the variance between-days and between-subjects has seldom been evaluated. This study aimed at such an evaluation. Six women performed three different work tasks: 'materials picking', 'light assembly', and 'heavy assembly', repeated on 3 different days. EMG was recorded from m. trapezius, m. infraspinatus and the forearm extensors. Normalisation was made to a maximal (MVE), and a submaximal (RVE), reference contraction. Variance components between days (within subjects) and between subjects were derived for the 10th, 50th and 90th percentiles, as well as for muscular rest parameters. For the task 'heavy assembly', the coefficient of variation between days (CV(BD)) was 8% for m. trapezius (right side, 50th percentile, MVE normalised values). Larger variabilities were found for m. infraspinatus (CV(BD) 15%), and the forearm extensors (CV(BD) 33%). Between-subjects variability (CV(BS)) was greater, 16% for m. trapezius and 57% for m. infraspinatus, 29% for the forearm extensors. RVE normalisation resulted in larger CV(BD), while reducing CV(BS). The between-days and between-subjects variability may be used to optimise sampling strategy, and to assess the bias in epidemiological studies. The bias caused by measurement procedures per se is acceptable.


Asunto(s)
Electromiografía , Destreza Motora/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Carga de Trabajo/clasificación , Adulto , Análisis de Varianza , Dorso , Sesgo , Fenómenos Biomecánicos , Electromiografía/estadística & datos numéricos , Femenino , Antebrazo , Humanos , Industrias , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , Hombro , Factores de Tiempo , Grabación de Cinta de Video
19.
J Electromyogr Kinesiol ; 14(3): 355-67, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15094149

RESUMEN

Flexible biaxial goniometers are extensively used for measuring wrist positions and movements. However, they display an inherent crosstalk error. The aim was to evaluate the effect, of this error, on summary measures used for characterizing manual work. A goniometer and a torsiometer were combined into one device. An algorithm that effectively compensated for crosstalk was developed. Recordings from 25 women, performing five worktasks, were analyzed, both with and without compensation for crosstalk. The errors in the 10th, 50th and 90th percentiles of the flexion/extension distributions were small, on average <1 degrees. The ulnar/radial deviation distributions were weakly dependent on forearm position. The flexion/extension velocity measures were, for the 50th and 90th percentiles, as well as the mean velocity, consistently underestimated by, on average, 3.9%. For ulnar/radial deviation, the velocity errors were less consistent. Mean power frequency, which is a measure of repetitiveness, was insensitive (error <1%) to crosstalk. The forearm supination/pronation angular distributions were wider, and the velocities higher, than for the wrists. Considering wrist/hand exposure in epidemiologic studies, as well as for establishing and surveillance of exposure limits for prevention of work-related upper extremity musculoskeletal disorders, the crosstalk error can, when considering other errors and sources to variation, be disregarded.


Asunto(s)
Algoritmos , Diagnóstico por Computador/métodos , Antebrazo/fisiología , Movimiento/fisiología , Postura/fisiología , Muñeca/fisiología , Artefactos , Diagnóstico por Computador/instrumentación , Análisis de Falla de Equipo , Femenino , Humanos , Examen Físico/instrumentación , Examen Físico/métodos , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis y Desempeño de Tareas , Transductores
20.
Appl Ergon ; 35(1): 49-56, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14985140

RESUMEN

This study compares questionnaire assessed physical activity with direct technical measurements among cleaners and office workers, stratified regarding age, gender and self-reported neck/shoulder complaints. During two full working days number of steps was recorded by a pedometer, sitting/standing positions by a posimeter and heart rate by a Sport-Tester. In addition the subjects kept a work task diary for 10 days. There were high intra-individual variations in exposure between the days. Subjects with complaints rated their exposure higher than those without, although they in fact showed lower direct measured exposure. This may imply underestimation of exposure-effect relationships. Rate of perceived exertion showed low correlation with heart rate ratio within the two occupational groups, but high, 0.64 when the two groups were combined. Age and complaints explained 31% of the variance for the cleaners.


Asunto(s)
Frecuencia Cardíaca/fisiología , Actividad Motora , Exposición Profesional/análisis , Postura/fisiología , Análisis y Desempeño de Tareas , Carga de Trabajo , Adulto , Factores de Edad , Femenino , Tareas del Hogar , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Musculoesqueléticas/etiología , Enfermedades Musculoesqueléticas/psicología , Exposición Profesional/efectos adversos , Administración de Consultorio , Autoevaluación (Psicología) , Factores Sexuales , Encuestas y Cuestionarios
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