963 resultados para fetal losses


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Many of the reproductive disorders that emerge in adulthood have their origin during fetal development. Numerous studies have demonstrated that exposure to endocrine disrupting chemicals can permanently affect the reproductive health of experimental animals. In mammals, male sexual differentiation and development are androgen-dependent processes. In rat, the critical programming window for masculinization occurs between embryonic days (EDs) 15.5 and 19.5. Disorders in sex steroid balance during fetal life can disturb the development of the male reproductive tract. In addition to the fetal testis, the adrenal cortex starts to produce steroid hormones before birth. Glucocorticoids produced by the adrenal cortex are essential for preparing the fetus for birth. In the present study, the effects of exposure to endocrine disrupters on fetal male rat testicular and adrenal development were investigated. To differentiate the systemic and direct testicular effects of endocrine disrupters, both in vivo and in vitro experiments were performed. The present study also clarified the role of desert hedgehog signalling (Dhh) in the development of the testis. The results indicate that endocrine disrupters, diethylstilbestrol (DES) and flutamide, are able to induce rapid steroidogenic changes in fetal rat testis under in vitro conditions. Although in utero exposure to these chemicals did not show overt effects in fetal testis, they can induce permanent changes in the developing testis and accessory sex organs later in life. We also reported that exposure to antiandrogens can interfere with testicular Dhh signalling and result in impaired differentiation of the fetal Leydig cells and subsequently lead to abnormal testicular development and sexual differentiation. In utero exposure to tetrachlorodibenzo-p-dioxin (TCDD) caused direct testicular and pituitary effects on the fetal male rat but with different dose responses. In a study in which the effects of developmental exposure to environmental antiandrogens, di-isononylphthalate and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p-DDE), on fetal male rat steroidogenesis were investigated, chemicals did not down-regulate testicular or adrenal steroid hormone synthesis or production in 19.5-day-old fetal rats. However, p,p-DDE-treatment caused clear histological and ultrastructural changes in the prenatal testis and adrenal gland. These structural alterations can disturb the development and function of fetal testis and adrenal gland that may become evident later in life. Exposure to endocrine disrupters during fetal life can cause morphological abnormalities and alter steroid hormone production by fetal rat Leydig cells and adrenocortical cells. These changes may contribute to the maldevelopment of the testis and the adrenal gland. The present study highlights the importance of the fetal period as a sensitive window for endocrine disruption.

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Using microdata, we analyse the determinants of firm relocation and conventional outsourcing decisions as a way to reduce employment. The results for a sample of 32 countries show the relevance of factors not considered previously in the literature. Firms that are below average in quality or innovation have a higher propensity to externalise part of their production through outsourcing, while lower relative profitability and longer time to market for new products each imply a higher probability of relocation.

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The aim of the work is to study the existing analytical calculation procedures found in literature to calculate the eddy-current losses in surface mounted permanent magnets within PMSM application. The most promising algorithms are implemented with MATLAB software under the dimensional data of LUT prototype machine. In addition finite elements analyze, utilized with help of Flux 2D software from Cedrat Ltd, is applied to calculate the eddy-current losses in permanent magnets. The results obtained from analytical methods are compared with numerical results.

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En este artículo se presenta una actualización sobre el control del bienestar fetal anteparto, que incluye la monitorización biofísica con el test no estresante y el test estresante y su valoración. Se describen los parámetros de la frecuencia cardiaca fetal - la línea de base, la variabilidad y los ascensos transitorios de la frecuencia cardiaca fetal - en relación con los movimientos fetales, su significado clínico y la actuación que deriva del mismo.

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Controlar la frecuencia cardiaca fetal y la dinámica uterina durante el proceso del embarazo y el parto resulta de particular importancia para conocer el estado de salud de la madre y el niño. Hoy en día existen aparatos muy novedosos para este fin de uso generalizado en los hospitales españoles. De este tema se ocupa la Ficha de Utillaje de este mes analizando en qué consiste este monitor; cómo se utiliza, los pasos a seguir; etc.

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En este artículo se presenta una actualización sobre el control del bienestar fetal anteparto, que incluye la monitorización biofísica con el test no estresante y el test estresante y su valoración. Se describen los parámetros de la frecuencia cardiaca fetal - la línea de base, la variabilidad y los ascensos transitorios de la frecuencia cardiaca fetal - en relación con los movimientos fetales, su significado clínico y la actuación que deriva del mismo.

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Controlar la frecuencia cardiaca fetal y la dinámica uterina durante el proceso del embarazo y el parto resulta de particular importancia para conocer el estado de salud de la madre y el niño. Hoy en día existen aparatos muy novedosos para este fin de uso generalizado en los hospitales españoles. De este tema se ocupa la Ficha de Utillaje de este mes analizando en qué consiste este monitor; cómo se utiliza, los pasos a seguir; etc.

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En este artículo se presenta una actualización sobre el control del bienestar fetal anteparto, que incluye la monitorización biofísica con el test no estresante y el test estresante y su valoración. Se describen los parámetros de la frecuencia cardiaca fetal - la línea de base, la variabilidad y los ascensos transitorios de la frecuencia cardiaca fetal - en relación con los movimientos fetales, su significado clínico y la actuación que deriva del mismo.

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Controlar la frecuencia cardiaca fetal y la dinámica uterina durante el proceso del embarazo y el parto resulta de particular importancia para conocer el estado de salud de la madre y el niño. Hoy en día existen aparatos muy novedosos para este fin de uso generalizado en los hospitales españoles. De este tema se ocupa la Ficha de Utillaje de este mes analizando en qué consiste este monitor; cómo se utiliza, los pasos a seguir; etc.

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The mechanical harvesting is an important stage in the production process of soybeans and, in this process; the loss of a significant number of grains is common. Despite the existence of mechanisms to monitor these losses, it is still essential to use sampling methods to quantify them. Assuming that the size of the sample area affects the reliability and variability between samples in quantifying losses, this paper aimed to analyze the variability and feasibility of using different sizes of sample area (1, 2 and 3 m²) in quantifying losses in the mechanical harvesting of soybeans. Were sampled 36 sites and the cutting losses, losses by other mechanisms of the combine and total losses were evaluated, as well as the water content in seeds, straw distribution and crop productivity. Data were subjected to statistical analysis (descriptive statistics and analysis of variance) and Statistical Control Process (SCP). The coefficients of variation were similar for the three frames available. Combine losses showed stable behavior, whereas cutting losses and total losses showed unstable behavior. The frame size did not affect the quantification and variability of losses in the mechanical harvesting of soybeans, thus a frame of 1 m² can be used for determining losses.

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Brazil is amongst the world’s largest swine producers. However, its competitiveness has been vulnerable due to a lack of cooperation between the supply chain players. This condition makes the financial losses to be evaluated taking into account only an individual node, and most of the time, these damages are imputed by swine breeders. Living weight losses occur between the farm to slaughterhouses, and the main cause of these losses is the pre-slaughter handling, especially during animal transportation. In this research, we analyzed the pre-slaughter handling in a swine farm in Brasilândia, MS, Brazil. Analyzed data were provided by five slaughterhouses (farm clients) from the studied region, in which it was considered living weight losses, carcass bruising, animal injury, and death rate. The results indicated that total financial losses represent 160 thousand dollars per year, when taking into account the supply chain management.

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Foram analisadas retrospectivamente 26 pacientes gestantes traumatizadas, num período de nove anos. A média de idade foi 23,7 anos (16-42). A idade gestacional variou de dez a quarenta semanas (média 21,5 semanas); a maioria (46,1%) no segundo trimestre. O mecanismo predominante (65,3%) foi o trauma abdominal fechado por acidente automobilístico (atropelamento ou colisão). Na admissão, oito (30,7%) pacientes apresentavam alterações hemodinâmicas. Seis doentes (23,0%) apresentavam sangramento vaginal e, destas, quatro estavam hemodinamicamente normais. Analisamos a mortalidade materna, a mortalidade fetal e suas causas. Comparamos também a mediana dos valores do RTS e TRISS entre os grupos, sobrevida materno-fetal, sobrevida materna e óbito materno-fetal. Todas as gestantes admitidas com sangramento vaginal apresentaram óbito fetal. A mortalidade materna foi de 11,5%, por choque hemorrágico. A mortalidade fetal foi de 30,7%, sendo que 37,5% destes óbitos foram provocados pela morte materna. A principal causa de mortalidade fetal foi o descolamento de placenta (50,0%). Os índices de trauma, RTS e TRISS, foram significativamente menor (p=0,0025 e p<0,0001) no grupo óbito materno-fetal, porém esses índices não apresentaram valor prognóstico na mortalidade fetal.

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OBJETIVO: Estudar a influência da icterícia obstrutiva sobre a capacidade reprodutiva e desenvolvimento fetal em ratas. MÉTODOS: Foram utilizadas 60 ratas sexualmente maduras e sabidamente férteis distribuídas em dois grupos: grupo 1 (n=30)- submetidas a ligadura do ducto biliopancreático e grupo 2 (n=30) -controles. A partir do 23? dia pós-operatório, as ratas foram acasaladas e seus ciclos estrais avaliados diariamente por meio de esfregaços vaginais, que permitiram determinar o dia da cópula e a idade gestacional em que foram mortas. Realizou-se estudo histológico dos corpos lúteos nos ovários de todas as ratas e analisou-se macroscopicamente a morfologia externa dos fetos. RESULTADOS: Observou-se que 23 ratas controle (92%) e 11 ratas ictéricas (39,3%) desenvolveram prenhez (p=0,0002). As 17 ratas com hiperbilirrubinemia e sem prenhez (60,7%) apresentaram somente corpos lúteos com aspecto involutivo em seus ovários e sofreram modificações em seus ciclos estrais, permanecendo vários dias em proestro ou estro. As ratas prenhes com hiperbilirrubinemia não apresentaram alterações em seus corpos lúteos, porém os seus fetos eram anormais. CONCLUSÃO: Em presença de hiperbilirrubinemia, a fertilização é viável, a capacidade reprodutiva é muito reduzida, os ciclos estrais tornam-se irregulares, o epitélio vaginal permanece cornificado, os corpos lúteos ovarianos regridem, os corpos lúteos gravídicos não são alterados aumentando progressivamente durante a prenhez e o desenvolvimento fetal é gravemente alterado.

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Reliable detection of intrapartum fetal acidosis is crucial for preventing morbidity. Hypoxia-related changes of fetal heart rate variability (FHRV) are controlled by the autonomic nervous system. Subtle changes in FHRV that cannot be identified by inspection can be detected and quantified by power spectral analysis. Sympathetic activity relates to low-frequency FHRV and parasympathetic activity to both low- and high-frequency FHRV. The aim was to study whether intra partum fetal acidosis can be detected by analyzing spectral powers of FHRV, and whether spectral powers associate with hypoxia-induced changes in the fetal electrocardiogram and with the pH of fetal blood samples taken intrapartum. The FHRV of 817 R-R interval recordings, collected as a part of European multicenter studies, were analyzed. Acidosis was defined as cord pH ≤ 7.05 or scalp pH ≤ 7.20, and metabolic acidosis as cord pH ≤ 7.05 and base deficit ≥ 12 mmol/l. Intrapartum hypoxia increased the spectral powers of FHRV. As fetal acidosis deepened, FHRV decreased: fetuses with significant birth acidosis had, after an initial increase, a drop in spectral powers near delivery, suggesting a breakdown of fetal compensation. Furthermore, a change in excess of 30% of the low-to-high frequency ratio of FHRV was associated with fetal metabolic acidosis. The results suggest that a decrease in the spectral powers of FHRV signals concern for fetal wellbeing. A single measure alone cannot be used to reveal fetal hypoxia since the spectral powers vary widely intra-individually. With technical developments, continuous assessment of intra-individual changes in spectral powers of FHRV might aid in the detection of fetal compromise due to hypoxia.