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61.
Urinary cadmium levels during pregnancy and postpartum   总被引:4,自引:0,他引:4  
It is well established that pregnancy induces physiological, metabolical and hormonal changes. As a consequence, trace metal metabolism can be affected. The aim of the present study was to assess the urinary cadmium levels in women during gestation and postpartum. The survey was conducted in a group of nonoccupationally cadmium-exposed women from Southern Catalonia (NE, Spain). Urine samples were obtained before pregnancy, during the 6th, 10th, 26th, and 30th wk of gestation, as well as during the 5th and 24th wk after delivery. Urinary cadmium levels were determined by graphite furnace atomic absorption spectrophotometry. The concentrations of zinc and copper in plasma were also measured. Moreover, to assess the effect of the diet during pregnancy, dietary ingestions of zinc, iron, and calcium were also determined. A significant decrease of plasma zinc levels could be observed during the last two trimesters of pregnancy, while plasma copper concentrations significantly increased during the same period. Urinary cadmium concentrations ranged from 0.05 to 3.79 μg/g creatinine (geometric mean 0.49±2.26 μg/g creatinine). No significant changes in urinary cadmium concentrations during pregnancy and postpartum could be observed.  相似文献   
62.
目的:探讨甲状腺功能亢进(甲亢)孕妇经治疗后,其体内25-羟维生素D(25-(OH)D3)水平对42天婴儿胫骨声波的传导速度(speed of sound,SOS)值、骨代谢生化指标的影响。方法:选取我院门诊及住院确诊的甲亢孕妇40例为甲亢组(T组),随机抽取健康孕妇40例作为对照组(C组),甲亢组给予丙硫氧嘧啶治疗后,监测两组孕妇25-(OH)D3水平与生后42天婴儿的胫骨SOS值、骨代谢生化指标,并进行对比观察、统计分析。结果:甲亢组孕妇在产后42天体内25-(OH)D3的水平比其在产后第1天升高(P〈0.05),甲亢组孕妇在产后42天体内25-(OH)D3水平接近对照组(P〉0.05),在产后42天婴儿的胫骨SOS值接近对照组(P〉0.05),甲亢组产后42天婴儿的血清钙(Ca)及血清碱性磷酸酶(AKP)接近对照组(P〉0.05)。结论:甲亢组孕妇给予丙硫氧嘧啶治疗后,甲状腺功能恢复正常,其体内25-(OH)D3水平升高,所产42天婴儿的骨密度也随着升高。  相似文献   
63.
于春冬  陈佳红  于静  丁伟  张迪 《生物磁学》2011,(12):2295-2297
目的:了解青岛地区的孕妇在2001年-2009年间感传染性疾病的情况。方法:乙型肝炎表面抗原(HBsAg)、丙型肝炎病毒抗体(抗-HCV)、人免疫缺陷病毒抗体(抗-HIV)的检测采用酶联免疫吸附实验(ELISA),梅毒测定采用快速血浆反应素(RPR)环状卡片实验,对青岛地区2001年-2009年门诊收治的39369名孕妇的血液进行HbsAg、抗-HCV、抗-HIV、梅毒的检测,并对检测结果进行统计与分析。结果:2001年-2009年间青岛地区的孕妇产前感染以HBsAg多见,其次是梅毒感染和丙型肝炎病毒感染,阳性率分别为3.94%,0.18%和0.15%,抗-HIV暂未检出。各年间各种传染性疾病感染率无显著性差异(P〉0.05)。结论:通过对孕妇产前进行传染性标志物的检测,为临床预防及控制母婴垂直传播传染性疾病的发生提供了依据。  相似文献   
64.
目的:了解青岛地区的孕妇在2001年-2009年间感传染性疾病的情况。方法:乙型肝炎表面抗原(HBsAg)、丙型肝炎病毒抗体(抗-HCV)、人免疫缺陷病毒抗体(抗-HIV)的检测采用酶联免疫吸附实验(ELISA),梅毒测定采用快速血浆反应素(RPR)环状卡片实验,对青岛地区2001年-2009年门诊收治的39369名孕妇的血液进行HbsAg、抗-HCV、抗-HIV、梅毒的检测,并对检测结果进行统计与分析。结果:2001年-2009年间青岛地区的孕妇产前感染以HBsAg多见,其次是梅毒感染和丙型肝炎病毒感染,阳性率分别为3.94%,0.18%和0.15%,抗-HIV暂未检出。各年间各种传染性疾病感染率无显著性差异(P>0.05)。结论:通过对孕妇产前进行传染性标志物的检测,为临床预防及控制母婴垂直传播传染性疾病的发生提供了依据。  相似文献   
65.
Farrowing is an intrinsically risky process for both the sow and the piglets that can cause welfare and economic problems. The effects of the non-steroidal anti-inflammatory drug meloxicam on post-farrowing behaviour of sows, and the performance of piglets were investigated. A total of 48 sows were randomly allocated at the day of farrowing (day 0) into two homogeneous groups regarding parity, and treated with either meloxicam or saline solution as placebo. For each sow, number of position changes, total time lying and standing or sitting, feed intake and rectal temperature (RT) were recorded during 3 days after farrowing. Piglets were individually weighed at farrowing and at weaning. The number of position changes did not show significant differences between treatments (P = 0.79). Sows spent significantly less time lying during day +3 after farrowing in the meloxicam group than in the placebo group (P = 0.04). Feed intake and RT showed a parity effect (P < 0.001 in both cases); however, no treatment effect was observed (P = 0.67 and P = 0.47, respectively). Pre-weaning mortality rate in piglets was not affected by treatment. In litters from multiparous sows, piglets of low birth weight (defined as percentile 15: BW <1180 g) had an average daily gain significantly higher in the meloxicam group than in the placebo group (196.6 ± 7.2 v. 166.6 ± 9.1 g/day; P = 0.03). Although the administration of meloxicam 90 min after farrowing showed a positive effect on the total time lying of the sows, additional investigations are required to better qualify relevant indicators of pain following farrowing in sows and to specify the analgesic effects of meloxicam on piglet performance.  相似文献   
66.
Adult and immature male rats were hypophysectomized and injected daily with saline or 0.2 or 2 μg of superactive Luteinizing Hormone Releasing Hormone (LHRH) agonist, [D-Trp6]-LHRH subcutaneously for seven days - with, or without, concomitant treatment of 1 IU Human Chorionic Gonadotropin (hCG) or 50 IU Pregnant Mare Serum. The administration of [D-Trp6]-LHRH reduced Luteinizing Hormone/Human Chorionic Gonadotropin receptors in all cases. The magnitude of this reduction was dose-related. As small a dose as 0.2 μg of the peptide resulted in approximately a 72% reduction of the receptors. The results suggest a direct action of [D-Trp6]-LHRH on the testis. It also indicated that reduction of testicular Luteinizing Hormone/Human Chorionic Gonadotropin receptors by the peptide is not necessarily due to the over-stimulation of Luteinizing Hormone (LH) release from the pituitary through a “down regulation” mechanism.  相似文献   
67.
Ad libitum feeding of pregnant sows requires satiating, intake-restricting feed components to prevent sows from getting excessively fat. Because hindgut fermentation starts only after and proceeds much slower than enzymatic digestion in the small intestine, fermentation products might, as nutrients, induce a prolonged physiological satiation of sows. To simulate hindgut fermentation and determine the fermentative release of short-chain fatty acids (SCFA) in vitro, gas production tests (GPTs) were performed with different raw materials after removal of enzymatically hydrolysable compounds. Fresh feces from sows that received standard sow feed was used as inoculum. Fresh, ensiled, or dehydrated by-products of the food industry (brewers’ grains, liquid yeast feed, maize gluten feed, raw potato chips, potato steam peel, pressed potato pulp, sugar beet pulp (SBP)) and whole-plant products (grass, maize) were tested as individual products.

Balances were drawn up of the in vitro flow of organic carbon (OC) to an “ileal” nutrient fraction, a “hindgut” fraction of SCFA and gas, and “fecal” remnants. The OC balances revealed large variations among raw materials in terms of their contribution to the different fractions. Potato steam peel gave the largest “ileal” nutrient fraction (77% of total OC), the lowest was observed with fresh sugar beet pulp (9% of total OC). In the GPT, SBP, and potato pulp brought about the highest “hindgut” SCFA yields (32–49% of total OC), and together with raw potato chips, the highest amounts of gas. Grass products and liquid yeast feed were slower fermented than most by-products. Moreover, whole-plant materials gave larger “fecal” OC portions than by-products, with the exception of fresh and dehydrated brewer’s grains. Together with straw, the latter were the least degradable of all raw materials tested. Among the grass products, dehydrated grass, and among the by-products, raw potato chips left the least “fecal” residues, i.e. they were nutritionally utilized to the largest extent.  相似文献   

68.
目的:探讨不同声强超声对孕鼠子宫收缩及胎鼠神经损伤的影响及机制。方法:将32只孕鼠随机分为A(0)组、B(2)组、C(4)组、D(8)组,每组各8只,分别接受声强为0 W cm~(-2)、2 W cm~(-2)、4 W cm~(-2)和8 W cm~(-2)的超声辐照20 min。记录孕鼠子宫收缩及子宫平滑肌ATP酶的活力,检测胎鼠大脑皮层与海马神经元凋亡及胆碱能神经系统相关酶的活力。结果:超声增加孕鼠子宫收缩频率、收缩幅度、收缩张力和子宫活动度(P均0.05),降低孕鼠子宫平滑肌中钠钾ATP酶、钙ATP酶和钙镁ATP酶的活性(P均0.05)。超声降低胎鼠大脑皮层和海马中Bcl~(-2)水平(P0.05),增加Bax和Caspase-3水平(P均0.05)。以及促进乙酰胆碱酯酶活力,降低乙酰胆碱和乙酰胆碱转移酶水平(P均0.05)。且4 W cm~(-2)和8 W cm~(-2)的超声比2 W cm~(-2)超声对这些指标的作用更强。结论:4 W cm~(-2)和8 W cm~(-2)超声可能通过降低ATP酶的活性促进孕鼠子宫平滑肌收缩,并可引起胎鼠大脑皮层和海马神经元损伤,机制可能与胆碱能神经元系统失衡有关,2 W cm~(-2)声强的超声对胎鼠神经元损伤甚小。  相似文献   
69.
下生殖道病原微生物感染对孕妇妊娠结局的影响   总被引:2,自引:0,他引:2  
成玲  陈颖 《中国微生态学杂志》2008,20(6):582-583,585
目的了解本地区孕妇孕中期下生殖道病原微生物感染与不良妊娠结局的关系。方法真菌、滴虫、各种细菌、厌氧菌、支原体采用体外培养和生化反应的方法进行培养和鉴定,加德纳菌采用化学反应的方法检测唾液酸酶,沙眼衣原体采用金标法检测其抗原。结果有病原微生物感染所造成的不良妊娠结局明显高于无感染者(P〈0.01、P〈0.05),其中多种病原微生物感染所造成的危害大于单一病原微生物感染。结论孕妇孕中期病原微生物感染会增加不良妊娠结局的发生率。  相似文献   
70.
If loose-housed farrowing systems are to be an alternative to traditional farrowing crates, it is important that they can deliver the same production results as can be achieved in farrowing crates under commercial conditions. The aim of this study was to compare preweaning mortality in farrowing crates and free farrowing pens (FF-pens) within herds that had both systems. The study was conducted over 2 years in three commercial Danish herds that had FF-pens as well as traditional farrowing crates in their farrowing unit. Piglet mortality was analysed in two periods: before litter equalisation and after litter equalisation. Linear models were used to analyse effects of housing (crate or pen), herd (Herd A, B or C), parity (parities 1, 2, 3 to 4 or 5 to 8) as well as the effect of number of total born piglets on mortality before litter equalisation, and the effect of equalised litter size on piglet mortality after litter equalisation. All corresponding interactions were included in the models. Before litter equalisation piglet mortality was higher (P<0.001) in pens (13.7%) than in crates (11.8%). Similarly, piglet mortality after litter equalisation was higher in pens than in crates in all three herds, but the difference between pens and crates were dissimilar (P<0.05) in the different herds. In addition, piglet mortality, both before (P<0.001) and after litter equalisation (P<0.001), grew with increasing parity of the sows. Mortality before litter equalisation moreover increased with increasing number of total born piglets per litter (P<0.001), and mortality after equalisation increased when equalised litter size increased (P<0.001). No significant interactions were detected between housing and parity or housing and litter size for any of the analysed variables. In conclusion, there is knowledge how to design pens for free farrowing; but this study showed a higher preweaning mortality in the FF-pen. Nonetheless a noteworthy proportion of the sows in the FF-pens delivered results comparable to those farrowing in crates. This indicates that FF-pens are not yet a robust type of housing for farrowing sows.  相似文献   
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