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21.
This study report documents the development of a finite element (FE) model for analyzing trauma in pregnant women involved in road accidents and help the design of a specific safety device. The model is representative of a 50th percentile pregnant woman at 26 weeks of pregnancy in sitting position. To achieve this, the HUMOS 2 model, which has been validated in a wide range of dynamic tests, was scaled to the morphology of a woman in the 50th percentile and coupled with a model of gravid uterus. During scaling, special attention was paid to the pelvic region which is known to differ considerably in morphological terms between men and women. The gravid uterus model includes a placenta, a fetus, uterosacral ligaments and the amniotic fluid by means of fluid structure interaction formulation. The uterus and the female model were coupled using an original method whereby the growth of an uterus was simulated to compress the abdominal organs in a realistic manner. The model was validated based on experimental tests described in the literature. Additional tests based on abdominal loadings with a seatbelt on Post Mortem Human Surrogates (PMHS) coupled to silicone uterus were also performed.  相似文献   
22.
Changes in physical body size during gestation were monitored using 529 sets of sow measurements. All sows were from the same herd and production system with a range in parity from 1 to 8. Sows were individually weighed, P2 backfat thickness was determined by ultrasound and morphometric measurements of body size were taken five times during gestation: day 0 (at service), day 25, day 50, day 80 and day 110. The morphometric measurements included sow height (from floor to last rib at the midline, from floor to ventral surface and from floor to hip), heart girth, depth of last rib, length (from snout to tail and from anterior scapula to tail) and width (at ham, at last rib and at shoulder). Regression analyses were used to model the relationship between day of gestation or parity number and morphometric measurements of body size. Regression equations were also developed to estimate sow weight from physical measurements, day of gestation and parity. As expected, sow dimensions, in general, increased as pregnancy progressed and also with increasing parity number. The relationships between day of gestation and body dimensions were described by linear and quadratic regression models, which had a range of adjusted R2 values up to 0.99. Similar relationships to parity number had a range of R2 values between 0.51 and 0.96. Sow depth, which can be used as an estimate of the width of the sow when lying, equalled the maximum width of the gestation stall (650 mm) at day 103 of gestation. However, by day 40 of gestation, predicted mean sow depth (570 mm) equalled the width at the rear of the crate. The implication of this is that after day 40 of gestation, the average sow was too wide for the rear of the crate when lying in a recumbent position. On day 110 of gestation, 95% of the mean sow body depths would be accommodated in stalls that were 674 mm wide; however, the range in body sizes with increasing parity number suggests the use of more than one stall width would be appropriate. Sow weight could be estimated with an adjusted R2 value of 0.81 and with a residual standard deviation (r.s.d.) of 16.5 kg using heart girth alone, or more accurately using a model with parity, day of gestation, P2 backfat depth and heart girth as the parameters (R2 = 0.89, r.s.d. 12.4 kg).  相似文献   
23.
目的观察凝结芽孢杆菌活菌片(商品名:爽舒宝)预防先兆流产保胎妇女胃肠功能紊乱的临床疗效。方法将60例先兆流产保胎妇女随机分为爽舒宝预防组和对照组,预防组30例,对照组30例,两组均给予常规服用保胎药物,出现顽固性便秘后用开塞露通便,其中预防组在此基础上同时口服凝结芽孢杆菌活菌片首次2. 1 g,以后1.05 g/次,3次/d,温水送服,疗程2-4周。观察保胎期间孕妇胃肠功能紊乱情况和使用开塞露的通便次数。结果预防组患者胃肠功能紊乱的发生率显著低于对照组,差异有统计学意义(P〈0.05 )。结论凝结芽孢杆菌活菌片预防先兆流产保胎妇女胃肠功能紊乱疗效显著,值得临床推广。  相似文献   
24.
Determination of appropriate nutritional requirements is essential to optimize the productivity and longevity of lactating sows. The current recommendations for requirements do not consider the large variation between animals. Therefore, the aim of this study was to determine the amino acid recommendations for lactating sows using a stochastic modeling approach that integrates population variation and uncertainty of key parameters into establishing nutritional recommendations for lactating sows. The requirement for individual sows was calculated using a factorial approach by adding the requirement for maintenance and milk. The energy balance of the sows was either negative or zero depending on feed intake being a limiting factor. Some parameters in the model were sow-specific and others were population-specific, depending on state of knowledge. Each simulation was for 1000 sows repeated 100 times using Monte Carlo simulation techniques. BW, back fat thickness of the sow, litter size (LS), average litter gain (LG), dietary energy density and feed intake were inputs to the model. The model was tested using results from the literature, and the values were all within ±1 s.d. of the estimated requirements. Simulations were made for a group of low- (LS=10 (s.d.=1), LG=2 kg/day (s.d.=0.6)), medium- (LS=12 (s.d.=1), LG=2.5 kg/day (s.d.=0.6)) and high-producing (LS=14 (s.d.=1), LG=3.5 kg/day (s.d.=0.6)) sows, where the average requirement was the result. In another simulation, the requirements were estimated for each week of lactation. The results were given as the median and s.d. The average daily standardized ileal digestible (SID) protein and lysine requirements for low-, medium- and high-producing sows were 623 (CV=2.5%) and 45.1 (CV=4.8%); 765 (CV=4.9%) and 54.7 (CV=7.0%); and 996 (CV=8.5%) and 70.8 g/day (CV=9.6%), respectively. The SID protein and lysine requirements were lowest at week 1, intermediate at week 2 and 4 and the highest at week 3 of lactation. The model is a valuable tool to develop new feeding strategies by taking into account the variable requirement between groups of sows and changes during lactation. The inclusion of between-sow variation gives information on safety margins when developing new dietary recommendations of amino acids and protein for lactating sows.  相似文献   
25.
Classic polycystic ovary syndrome (PCOS) is a high-risk phenotype accompanied by increased risks of reproductive and metabolic abnormalities; however, the local metabolism characteristics of the ovaries and their effects on germ cell development are unclear. The present study used targeted metabolomics to detect alterations in the intermediate metabolites of follicular fluid from classic PCOS patients, and the results indicated that hyperandrogenism but not obesity induced the changed intermediate metabolites in classic PCOS patients. Regarding the direct contact, we identified mitochondrial function, redox potential, and oxidative stress in cumulus cells which were necessary to support oocyte growth before fertilization, and suggested dysfunction of mitochondria, imbalanced redox potential, and increased oxidative stress in cumulus cells of classic PCOS patients. Follicular fluid intermediary metabolic profiles provide signatures of classic PCOS ovary local metabolism and establish a close link with mitochondria dysfunction of cumulus cells, highlighting the role of metabolic signal and mitochondrial cross talk involved in the pathogenesis of classic PCOS.  相似文献   
26.
目的:探讨同型半胱氨酸(homocysteine,HCY)摄入后对孕鼠糖代谢的影响以及生物学机制分析。方法:孕鼠妊娠10 d后,将实验动物随机分为3组,每组12只,妊娠对照组(Ctrl)腹腔注射生理盐水,同型半胱氨酸高剂量组(HCYH)和同型半胱氨酸低剂量组(HCYL)腹腔注射HCY溶液,注射浓度分别为200 mg/kg·d和100 mg/kg·d,持续20 d(即为HCY20 d)后,利用血糖含量检测试剂盒和胰岛素试剂盒分别检测孕鼠空腹血糖水平、胰岛素水平;葡萄糖检测试剂盒对孕鼠葡萄糖耐量和胰岛素抵抗进行检测;蛋白免疫印迹法检测孕鼠目的蛋白过氧化物酶体增殖物激活受体γ(PPARγ)、葡萄糖转运蛋白4(GLUT4)、蛋白激酶B(AKT)、磷酸化AKT蛋白(P-AKT)的表达。结果:与Ctrl组比较,在孕鼠注射HCY后,空腹血糖水平升高、血清中胰岛素浓度下降、HOMA-β指数下降、HOMA-IR指数升高(P<0.05);摄入葡萄糖后,孕鼠血糖随时间的变化而下降,葡萄糖曲线下面积升高(P<0.05);摄入胰岛素后,孕鼠血糖随时间的变化而升高,胰岛素曲线下面积升高(P<0.05);PPARγ、P-AKT、GLUT4蛋白表达水平下降,HCYH组降低水平更为显著(P<0.05)。结论:孕鼠HCY摄入后,生物体糖代谢紊乱,AKT磷酸化表达水平抑制,HCY可能通过降低PPARγ的表达减少AKT磷酸化,导致胰岛素受体的活化,进而激活了PI3K/AKT通路,减少了脂肪组织中的GLUT4表达,增加了对于葡萄糖的摄取能力。  相似文献   
27.
目的 探讨妊娠妇女与无性生活女性阴道分泌物中菌群结构差异,为临床女性泌尿生殖系统疾病研究提供可靠的依据。方法 运用高通量二代测序技术检测20例妊娠妇女和29例无性生活女性阴道分泌物中微生物;采用秩和检验进行组间显著性差异分析,使用生物信息学软件进行数据处理。结果 49份样本共注释出14个门、23个纲、33个目、28个科、38个属和23个种水平物种。妊娠妇女与无性生活女性阴道分泌物中菌群结构差异显著。妊娠妇女在种水平仅有Atopobium vaginae、Campylobacter ureolyticus、Lactobacillus coleohominis、德氏乳杆菌、瑞氏乳杆菌、惰性乳杆菌、罗伊乳杆菌、白假丝酵母和近平滑假丝酵母共9个物种。结论 妊娠能引起女性阴道分泌物菌群结构发生改变,且菌种数量明显减少。Lactobacillus coleohominis和德氏乳杆菌可能在维持妊娠妇女阴道菌群平衡和自净作用中起到关键性作用。  相似文献   
28.
PurposeTo assess the radiation dose to the fetus of a pregnant patient undergoing high-dose-rate (HDR) 192Ir interstitial breast brachytherapy, and to design a new patient setup and lead shielding technique that minimizes the fetal dose.MethodsRadiochromic films were placed between the slices of an anthropomorphic phantom modeling the patient. The pregnant woman was seated in a chair with the breast over a table and inside a leaded box. Dose variation as a function of distance from the implant volume as well as dose homogeneity within a representative slice of the fetal position was evaluated without and with shielding.ResultsWith shielding, the peripheral dose after a complete treatment ranged from 50 cGy at 5 cm from the caudal edge of the breast to <0.1 cGy at 30 cm. The shielding reduces absorbed dose by a factor of two near the breast and more than an order of magnitude beyond 20 cm. The dose is heterogeneous within a given axial plane, with variations from the central region within 50%. Interstitial HDR 192Ir brachytherapy with breast shielding can be more advantageous than external-beam radiotherapy (EBRT) from a radiation protection point of view, as long as the distance to the uterine fundus is higher than about 10 cm. Furthermore, the weight of the shielding here proposed is notably lower than that needed in EBRT.ConclusionsShielded breast brachytherapy may benefit pregnant patients needing localized radiotherapy, especially during the early gestational ages when the fetus is more sensitive to ionizing radiation.  相似文献   
29.
Over the last decades, permanent crating of farrowing and lactating sows has led to serious public concerns with regard to sow welfare. As one alternative, it has been suggested to restrict crating to the period when suckling piglets are at the highest risk to die. Therefore, the aim of this study was to investigate live-born piglet mortality with regard to different confinement periods (CFP) as well as farrowing pen types. On three research farms (A, B and C), four confinement periods were compared: In CFP 0 (control), sows were not confined at all, sows in CFP 3 were crated after the end of farrowing for three days. In CFP 4, sows were confined one day before the due date of farrowing until three days after parturition and sows in CFP 6 were crated one day before expected farrowing until five days after parturition. Furthermore, five different pen types designed for temporary crating (PT; 5.5–7.3 m2) were compared. In total, production data from 638 litters were analysed. For each piglet found dead (n = 1 580), the cause of death was determined by the farm personnel and verified by necropsy (all three farms) and additional video analysis (farms A and B only). Data were analysed using logistic mixed models with CFP 0 and pen type Fluegel as reference categories (CFP 0 was control and this pen type was present on all three farms and the largest number of litters was born in this pen type). Live-born piglet mortality was lower in temporarily crated sows than in sows without confinement (CFP 0; P < 0.015). Pairwise posthoc tests did not reveal differences between CFP 3, CFP 4 and CFP 6 (odds ratios 0.75, 0.59 and 0.69), nor between pen types. Additional factors associated with increasing live-born piglet mortality were larger litter size, higher sow parity as well as the administration of hormones around farrowing. Factors influencing mortality due to crushing were similar to those for total live-born mortality with the exception of CFP 3 not differing significantly from CFP 0. It can be concluded, that confinement of the sow for three days after farrowing is an effective measure to reduce live-born piglet mortality in the pen types tested. An extension of the confinement period to five days after parturition does not result in a further reduction of live-born mortality rate.  相似文献   
30.
This study aimed to evaluate whether adding straw to a loose-farrowing house promotes maternal functions and production. Forty-eight sows (Landrace× Large White) were housed in either a farrowing pen without straw (C, n = 24) or with straw (S, n = 24). Behaviors were observed using video recordings and were statistically analyzed. Lateral recumbency was higher and standing was lower in S compared with C (p = .034 and p = .020, respectively), and lateral recumbency to other postures, ventral to lateral recumbency and standing to lying were markedly lower in S than C (p = .014, p = .025 and p = .023, respectively) on Day 1 postpartum. However, except piglet losses during the first three days postpartum (p = .032), piglet weight on Day 21 (p = .037), and piglet weaning weight (p = .020), other production performances were not significantly different between the two groups during the whole experimental period (p ?.05). The results suggest the enrichment of a farrowing pen with straw has important beneficial effects on sow and piglet welfare and improves piglet survival rates.  相似文献   
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