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721.
Allison C. Sylvetsky Viviana Bauman Jenny E. Blau H. Martin Garraffo Peter J. Walter 《毒物与环境化学》2017,99(3):535-542
We aimed to measure concentrations of the commonly used artificial sweetener sucralose, following ingestion of doses reflecting a range of consumption and to compare concentrations in children and adults. Eleven adults consumed 355 mL water containing 0 mg (control), 68, 170, or 250 mg sucralose (equivalent to 1–4 diet sodas). A second group of adults (n = 11) consumed 355 mL Diet Rite Cola? (68 mg sucralose and 41 mg acesulfame-potassium (ace-K)) or 68 mg sucralose and 41 mg ace-K in seltzer. Beverages were provided at separate visits in randomized order, prior to an oral glucose tolerance test. Eleven children consumed 0 or 68 mg sucralose in 240 mL water, in an identical study design. Blood was collected before beverage ingestion and serially for 120 min. Sucralose doses (corrected for weight) resulted in similar plasma concentrations in children and adults. Concentrations were comparable whether sucralose was administered in water, combined with ace-K, or in diet soda. Due to their lower body weight and blood volume, children have markedly higher plasma sucralose concentrations after the consumption of a typical diet soda, emphasizing the need to determine the clinical implications of sucralose use in children. 相似文献
722.
Carlos Palacín Juan C. Alonso Carlos A. Martín Javier A. Alonso 《Conservation biology》2017,31(1):106-115
Many bird populations have recently changed their migratory behavior in response to alterations of the environment. We collected data over 16 years on male Great Bustards (Otis tarda), a species showing a partial migratory pattern (sedentary and migratory birds coexisting in the same breeding groups). We conducted population counts and radio tracked 180 individuals to examine differences in survival rates between migratory and sedentary individuals and evaluate possible effects of these differences on the migratory pattern of the population. Overall, 65% of individuals migrated and 35% did not. The average distance between breeding and postbreeding areas of migrant individuals was 89.9 km, and the longest average movement of sedentary males was 3.8 km. Breeding group and migration distance had no effect on survival. However, mortality of migrants was 2.4 to 3.5 times higher than mortality of sedentary birds. For marked males, collision with power lines was the main cause of death from unnatural causes (37.6% of all deaths), and migratory birds died in collisions with power lines more frequently than sedentary birds (21.3% vs 6.3%). The percentage of sedentary individuals increased from 17% in 1997 to 45% in 2012. These results were consistent with data collected from radio‐tracked individuals: The proportion of migratory individuals decreased from 86% in 1997–1999 to 44% in 2006–2010. The observed decrease in the migratory tendency was not related to climatic changes (temperatures did not change over the study period) or improvements in habitat quality (dry cereal farmland area decreased in the main study area). Our findings suggest that human‐induced mortality during migration may be an important factor shaping the migration patterns of species inhabiting humanized landscapes. 相似文献
723.
The prenatal detection of hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8) deficiency, the Lesch-Nyhan syndrome, during the first trimester of an affected pregnancy through the use of chorionic villus sampling is reported. Quantitation of reaction products formed by villus cell extracts from exogenous hypoxanthine-8-[14C] or adenine-8-[14C] is used in diagnosis. We report the diagnosis of Lesch-Nyhan syndrome using a chorionic villus specimen and confirmation of that diagnosis. In addition, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), enzymes deficient in inherited immune disorders, are detected in chorionic villus samples. These heritable disorders also appear amenable to early prenatal diagnosis. 相似文献
724.
C. Marchese M.D. E. Savin E. Dragone F. Carozzi M. De Marchi M. Campogrande G. C. Dolfin G. Pagliano E. Viora A. Carbonara 《黑龙江环境通报》1985,5(3):221-227
Six cases of cystic hygromas detected during second trimester ultrasound examination are reported: 4 fetuses (67 per cent) had a 45, X karyotype, 1 fetus had trisomy 18, 1 fetus had a normal karyotype (46,XX) and at autopsy multiple anomalies were observed. In the latter case the family history suggested an autosomal recessive pattern of inheritance. In order to reach a definite diagnosis and give proper genetic counselling when a fetus is found to have cystic hygroma, a fetal karyotype as well as a family and reproductive history should be obtained. 相似文献
725.
D. Arduini G. Rizzo C. Giorlandino A. Vizzone S. Nava S. Dell'Acqua H. Valensise C. Romanini 《黑龙江环境通报》1985,5(4):269-276
In order to accurately detect the fetal behavioural state, we simultaneously measured fetal heart rate and multiple fetal activities in 27 healthy pregnant women at 38 to 40 weeks of gestation. We ultrasonically identified gross body movements, breathing movements and micturition. Analysis of fetal heart rate allowed us to distinguish two different patterns of fetal behaviour: active and quiet phases. The frequency distribution of the analysed fetal events was significantly different in these two phases. These data suggest that a complete biophysical profile of the fetus is effective in differentiating behavioural states and may improve the predictive accuracy of fetal heart rate analysis alone. 相似文献
726.
The outcome of the pregnancy following (a) a mid-trimester termination of pregnancy (TOP) for fetal neural tube defect (NTD) (77 women=group 1); (b) mid-trimester TOP for fetal Down's syndrome (13 women=group 2); (c) delivery of a baby with NTD (119 women=group 3) was studied. The prenatal fetal loss was relatively high in all groups. In group 1 it was similar to that found in other studies after first trimester TOP, in group 2 it was associated with advanced maternal age and the unexpected finding in group 3 was not attributable to advanced maternal age. It is suggested that a previous NTD per se might increase the risk of fetal loss in the next pregnancy. A previous mid-trimester TOP for NTD was not associated with an increase in premature labour, small for dates babies or congenital abnormality in the next pregnancy, but there was a slight increase in the number of babies weighing less than 2500 g. 相似文献
727.
Emanuela Terzian Jillian Boreham Howard S. Cuckle Nicholas J. Wald Martin Bobrow Richard Lindenbaum A. C. Turnbull 《黑龙江环境通报》1985,5(6):401-414
A survey was conducted of the results of mid-trimester diagnostic amniocenteses in the Oxford Region from 1974 to 1981. The survey used data relating to all 4357 singleton pregnancies in which an amniocentesis was performed during this period. Follow-up information on outcome was obtained in respect of 4284 (98 per cent) pregnancies. A cell culture to determine karyotype and an alpha-fetoprotein determination was carried out in all cases. From 1974 to 1981 amniocenteses became increasingly common, rising from 2 to 32 per 1000 births. The most common indication for amniocentesis was a high risk of a chromosome abnormality–56 per cent of all amniocenteses. Within this group advanced maternal age was responsible for 89 per cent of the cases. The next most common indication was a high risk of a neural tube defect (37 per cent of all amniocenteses)–in 1974 a raised maternal serum alpha-fetoprotein level accounted for only 4 per cent of these; by 1981 this had risen to 67 per cent. There were seven false-positive and 132 true-positive diagnoses of neural tube defect; since 1981, with the introduction of amniotic fluid acetylocholinesterase determination as a secondary diagnostic test for neural tube defects, there have been no further false-positive diagnoses. In 1981 76 per cent of women aged 35 years or more did not have an amniocentesis. It is not known to what extent this was due to not offering women in this age group amniocentesis or to women not accepting such an offer. 相似文献
728.
G.?Zi?baEmail authorView authors OrcID profile M.?Dukowska M.?Przybylski M.?G.?Fox C.?Smith 《Die Naturwissenschaften》2018,105(3-4):26
Providing parental care is potentially costly. Costs can arise through elevated energy expenditure or from an increased risk of mortality. A cost of parental care can also occur because a parent is compromised in their ability to forage. We used pumpkinseed Lepomis gibbosus, a fish with an alternative male mating strategy, to test whether parental males differed in their feeding in comparison with females and cuckolder males. To address this question, we examined the stomach contents of female, cuckolder male, and parental male pumpkinseed during the breeding season over an entire diel cycle. We showed that parental males had a lower total weight of food in their stomachs in comparison with females, while cuckolder males did not. Parental males also had a lower weight and number of chironomids in their stomachs. The temporal pattern of feeding of parental males diverged from that of females, and they had a lower probability of pupal chironomids in their stomachs, which implies spatial segregation in foraging. Parental males had a greater probability of conspecific eggs in their stomachs than females, while the probability of egg cannibalism did not differ between cuckolder males and females. Overall, these finding meet predictions in accordance with an assumption that parental care and territoriality can compromise feeding. 相似文献
729.
Juliano?Almeida?de?FariaEmail author José?Célio?Silveira?Andrade S?nia?Maria?da?Silva Gomes 《Mitigation and Adaptation Strategies for Global Change》2018,23(7):995-1018
Concerns about climate change as a result of anthropic actions have led to an increase in the volume of information disclosed about it in the reports of companies that are members of the Carbon Disclosure Project (CDP). In this context, the factors most disclosed remain obscure due to both the complexity of climate change impacts and the stakeholders’ different interests. This study aims to identify which factors are most disclosed in the reports of companies that are members of CDP. For this purpose, it is necessary to investigate if the factors indicated by managers and experts are the main ones disclosed in the reports of Brazilian companies that are members of CDP, as well as to identify which companies stand out in climate change disclosure based on these factors. To this end, 463 reports submitted by 48 companies between 2014 and 2016 were examined and 32 factors were investigated using the NVivo® software. Some companies submitted reports with unified titles, which reduced the sample. The results indicate that certain factors—prevention of pollution, prevention of loss, management of environmental assets, volume of greenhouse gas (GHG) emissions, and climate change strategy—account for 50.03% of the total volume of information disclosed about climate change. The main lesson learned from this research is that climate change mitigation strategy is strongly supported by the evidence of corporate annual reports, and it has relation with the following determinant factors: pollution prevention, loss prevention, environmental asset management, GHG emissions, and the strategy chosen by the companies to deal with climate change. Due to the low volume of research related to loss prevention and pollution prevention, we have identified that little attention has been paid to these items. Based on our results, we recommend that climate change mitigation strategies begin to consider these determinant factors in their structure because both have a strong influence in demonstrating how companies are managing these factors for stakeholders. Therefore, companies can benefit from this data to manage their resources for the maintenance of the social contract (legitimacy) through the factors most disclosed, especially companies with lower scores on the scale of ranking presented. Hence, stakeholders can have access to more information on strategies that mitigate climate change and help companies improve the disclosure of the actions that contribute to reduction of GHG emissions. 相似文献
730.