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1.
Workers in physically demanding occupations require work breaks to recover from exertion. In a laboratory setting, we investigated the impact of ergometer cycling for 7 h in two conditions with an identical total break time but with two different activity-rest schedules. We hypothesised that more frequent but shorter breaks lead to less psychophysical strain and its effects than do less frequent but longer breaks, particularly for older workers. Twenty-nine participants representing three different age groups were tested in both conditions. Heart rate, perceived exertion/tension and feelings of fatigue were assessed and used as dependent variables. Results indicate no general activity-rest differences as well as no age-related differences of break effects under the condition of subjectively equal straining load. However, heart rate was found to be lower at some measurement points in the frequent-short-break condition and perceived exertion was lower in the infrequent-long-break condition. PRACTITIONER SUMMARY: Design of activity-rest schedules in physically demanding occupations is a key issue in the prevention of strain and hence of interest to ergonomists. Our study suggests that breaks during physically demanding work have the same effect if they are frequent and short or infrequent and long, regardless of age. 相似文献
2.
This work aimed to clarify the interaction between the fetus and pregnant patients with gestational diabetes mellitus (GDM), the lipid metabolomics analysis of the fetal umbilical cord blood of GDM patients and normal pregnant women were performed to screen out the specific lipid metabolites for pathogenesis of GDM. From 2019–2020, 21 patients with GDM and 22 normal pregnant women were enrolled in Hexian Memorial Hospital, Panyu District, Guangzhou. The general information such as weight, height, age, body mass index (BMI) before pregnancy were analyzed. Non-targeted metabonomic detection and analysis were performed in umbilical cord plasma using LC-MS method. The age, BMI, delivery methods, and infant weight were different between GDM and control. There were 167 lipid metabolites in umbilical cord blood associated with GDM. Among them, 158 upregulated and 9 downregulated in GDM. There were 13 dysregulated metabolites with C < 30, including Lyso-phosphatidyl-colines LPC 16:0, 18:2, 18:1, 18:0, 20:4 and 22:6, glycerophosphocholines PC O-16:1, oleoylcarnitine CAR 18:2 and 18:1, dihexosylceramides Hex2Cer 13:0;2O, phosphatidylethanolamine PE O-22:6_2:0 and PE O-22:6_3:0 and sphingomyelin SM 8:0; 2O/11:0. Those metabolites were associated with glycerophospholipid metabolism and sphingolipid metabolism. Therefore, Lyso-phosphatidyl-colines, glycerophosphocholines, oleoylcarnitine, dihexosylceramides, phosphatidylethanolamine, and sphingomyelin were main lipid metabolites of GDM, which might be used for diagnosis and treatment of GDM. 相似文献
3.
《Planning》2014,(1)
目的 探讨剖宫产切口瘢痕妊娠二维、三维超声参数与手术中出血量的相关性,分析影响手术出血量的独立危险因素。方法 收集2011年11月至2013年1月北京协和医院临床确诊为剖宫产切口瘢痕妊娠、并接受手术治疗的35例患者,术前进行二维及三维超声检查,获得病灶最大径、病灶平均径、病灶植入瘢痕面积、植入体积及植入深度;按有无胎心搏动、病灶类型、彩色多普勒血流分级及术前有/无甲氨蝶呤联合治疗进行分组。记录患者手术中出血量,分析超声参数与出血量的相关性,比较组间出血量差异;将病灶按出血量进行分组,≥200 ml组和<200 ml组,应用Logistic回归分析影响出血量的独立危险因素。结果 病灶最大径和病灶植入瘢痕面积与出血量存在线性关系(P=0.009和0.008)。病灶平均径、病灶植入体积、病灶植入深度与出血量无线性关系(P= 0.017, 0.044和0.423)。有/无胎心搏动组间出血量(分别为23.38和13.47 ml)差异有统计学意义(P=0.004);病灶类型、彩色多普勒血流分级及术前有/无甲氨蝶呤联合治疗组间出血量差异无统计学意义(P= 0.131, 0.044和0.047)。Logistic回归分析显示病灶植入瘢痕面积为影响手术中出血量的独立危险因素(P=0.007),受试者工作特征曲线下面积为0.839(0.606~1.071)。结论 剖宫产切口瘢痕妊娠病灶最大径、病灶植入瘢痕面积及有/无胎心搏动与手术中出血量密切相关,其中病灶植入瘢痕面积是影响剖宫产切口瘢痕妊娠手术中出血量的独立危险因素,本研究结果可为临床决策(包括是否手术及术式选择)提供重要参考依据。 相似文献
4.
目的:探讨阴道超声对剖宫产切口妊娠的诊断重要性。方法:2012年1月-2012年12月来本院检查,超声诊断为剖宫产切口妊娠的46例患者进行回顾性分析。结果:阴道超声诊断切口妊娠46例,误诊5例,余41例均经病理确诊。结论:阴道超声检查能够较为直观的显示妊娠位置,能够提供较为精准的定位,为临床诊断和治疗提供了较为重要的诊断依据。 相似文献
5.
《Contact lens & anterior eye》2019,42(3):283-288
PurposeTo evaluate topographic measurements of the anterior segment and densitometric measurements of the cornea and lens by Pentacam HR in different trimesters of pregnancy.MethodsThis prospective study included 150 healthy pregnant women in their first, second, or third trimester (Groups 1, 2 and 3, respectively) and 54 non-pregnant healthy women (Group 0). Topographic measurements, including central corneal thickness (CCT), corneal volume (CV), anterior chamber depth (ACD), corneal densitometry (CD) and lens densitometry (LD), were done with the Pentacam HR (Oculus, Wetzlar, Germany). The measurement results of the healthy pregnant women and non-pregnant healthy women were compared.ResultsCD values were found in Group 1 to be 13.19, in Group 2 to be 13.16, in Group 3 to be 13.17 and in Group 0 to be 13.22 (p = 0.811). The mean Group 1, Group 2, Group 3 and Group 0 LD-horizontal was 5.40 ± 0.5, 5.47 ± 0.38, 5.53 ± 0.44, 5.36 ± 0.43, respectively. The mean Group 1, Group 2, Group 3 and Group 0 LD-vertical was 5.6 ± 0.43, 5.66 ± 0.32, 5.71 ± 0.40 and 5.5 ± 0.44, respectively. Area LD values were higher in the advanced trimester period, and the only statistically significant difference was between Group 3 and Group 0 (p = 0.025). The difference between three-dimensional (3D) and peak LD values was not statistically significant between the groups (p = 0.89 and p = 0.91, respectively).DiscussionThe Pentacam HR seems to be an important option for the evaluation of LD, CD and topographic measurements of the anterior segment in pregnancy. In the present study, CD and LD, including LD-horizontal, LD-vertical, peak and 3D values, were not significantly different between pregnant women and non-pregnant women. 相似文献
6.
Postpartum depression (PPD) is a prevalent mood disorder estimated to affect 20%–40% of women worldwide after childbirth. In recent studies, the effect of vitamin D on prevention of mood disorders and depression has been investigated, but it is still unclear how vitamin D may affect PPD. The evidence on the relevance between vitamin D deficiency and PPD is inconsistent, and assessment of the recent literature has not previously been carried out. Moreover, there are few clinical studies on PPD and vitamin D supplementation. Five studies have so far assessed the relationship between the levels of vitamin D and PPD. Findings from cohort studies suggest that vitamin-D deficiency is related to the incidence of PPD and vitamin D may play a significant role in the recovery of women with PPD, but it is uncertain whether these actions are the effect of vitamin D on the function of hypothalamic-pituitary-adrenal (HPA) axis, the levels of estradiol, serotonin, pro-inflammatory cytokines, and/or of other mechanisms involved in PPD. 相似文献
7.
Understanding dietary patterns of women who exceed gestational weight gain (GWG) recommendations is crucial to promote healthier pregnancies. This study assessed nutrient intake, diet quality and GWG of participants in the Pregnancy, Exercise, and Nutrition (PEN) feasibility study who met or exceeded weight gain recommendations during pregnancy. The ASA24-2011, a web-based tool, was used to collect dietary intake data and dietary quality was assessed with the Healthy Eating Index (HEI)-2010 and the Diet Quality Index-Pregnancy (DQI-P). Fifty-three percent of PEN participants exceeded the 2009 IOM GWG recommendations; no significant associations were found between reported dietary quality and gestational weight gain. 相似文献
8.
LARISSA DANIELE BOBERMIN LARA SCOPEL MEDEIROS FERNANDA WEBER GIANCARLO TOMAZZONI DE OLIVEIRA LUCÉLIA SANTI WALTER ORLANDO BEYS-DA-SILVA CARLOS-ALBERTO GONÇALVES RÉ QUINCOZES-SANTOS 《Biocell》2022,46(12):2517-2523
Glial cells are crucial for maintaining central nervous system (CNS) homeostasis. They actively participate in immune responses, as well as form functional barriers, such as blood-brain barrier (BBB), which restrict the entry of pathogens and inflammatory mediators into the CNS. In general, viral infections during the gestational period can alter the embryonic and fetal environment, and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life, as highlighted by our group for Zika virus infection. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induces a cytokine storm and, during pregnancy, may be related to a more severe form of the coronavirus disease-19 (COVID-19) and also to higher preterm birth rates. SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells, which can compromise neuronal plasticity and synaptic function. However, the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS, including brain development during childhood and adulthood, remains undetermined. Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders, which are strongly related to the inflammatory response. Thus, based on these relationships, we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life, focusing on the potential role of glial cells. Thus, it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy. 相似文献
9.
Sex‐specific Alterations in Serology and the Expression of Liver FATP4 Protein in Offspring Exposed to High‐Fat Diet during Pregnancy and/or Lactation
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Changes in dietary composition will have a significant impact on the nutritional status of the mother and the offspring. To examine the relevant hormone level changes during lactation and the expression of fatty acid transporters in the placenta and liver under the condition of a high‐fat (HF) diet, we established HF animal models and conducted a cross‐fostering program to mimic the shift in diet. On gestation day (GD)18, the weight of placenta in the HF group was significantly higher than that in the control group (p < 0.05). HF‐fed male pups had a significantly lower serum insulin level, but the same phenomenon was not found in females. On the contrary, serum triacylglycerol (TAG) level presented a tendency to decrease only in female offspring. Oil red O staining showed lipid accumulation in the HF diet offspring livers. The mRNA levels of FATP4 in the placenta in the HF diet group were significantly upregulated compared to the control diet group (p < 0.05). High‐fat diet (HFD) consumption also altered the liver mRNA levels of FATP4, SREBP‐1, and SCD‐1 in the male offspring, while the changes in protein levels of FATP4 were not observed in either sex. In conclusion, maternal HF diet has a profound impact on offspring growth, metabolism, and the risk of metabolic disorders, which would depend on the exposure period of pregnancy and lactation. 相似文献
10.
Richard L. Doty 《Journal of chemical ecology》1986,12(2):497-511
An overview of relationships between psychophysical measures of olfactory function and reproductive neuroendocrine processes is presented. Human studies are emphasized, and the influences of gender, menstrual cycle phase, pregnancy, and injected gonadal hormones upon olfactory perception are discussed in detail.Supported by National Institute of Neurological and Communicative Disorders and Stroke grant NS 16365. 相似文献