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81.
    
Ovarian hormones affected some enzymes in reproductive tissues. Previous studies revealed Anethum graveolens (dill) seed extract elevated ovarian hormones. In this study, we compared the effects of dill seed and leaf extracts on some enzymes activities and infertility potential. Female Wistar rats were divided into three groups of control, dill seed and dill leaf aqueous extracts treated groups. Experimental groups received 1 mL of 0.5 g kg?1 of each extract orally for 25 days (five estrous cycles). Estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone concentrations were determined. Uterus and ovaries were removed and their glucose-6-phosphate dehydrogenase, lactate dehydrogenase, and alkaline phosphatase activities were measured. Female rats of three groups were mated with untreated males. Fetuses were extracted in the 20th gestational day and their weights and crown rump lengths were measured. Anti-fertility and anti-implantation activities and fertility indices were calculated. Glucose-6-phosphate activity of dill seed treated group increased 1.6 times in the endometrium and 1.7 times in the myometrium. Progesterone concentration and lactate dehydrogenase activity of serum increased in the dill seed treated group compared to the control and dill leaf treated group. A significant decrease was observed in weights and crown rump lengths of fetuses, weights of placenta, and fertility index of the dill seed treated group compared to the control and dill leaf treated group, but its anti-implantation and anti-fertility indices increased. We suggested that high level of glucose-6-phosphate could entail increased oxidative stress in uterus and ovary. High lactate dehydrogenase activity in serum may affect cell membranes. Higher secretion of progesterone caused hormonal imbalance and produced estrous cycle irregularity. It was concluded that dill seed but not dill leaf extract could induce infertility in an animal model.  相似文献   
82.
Under laboratory conditions, female rainbow trout were exposed to graded concentrations of water from the River Lambro, a polluted tributary of the River Po, and to the effluent of a large wastewater treatment plant which flows into the River Lambro. In field exposures, trout were held in cages in the River Po upstream and downstream from the confluence of the River Lambro. After 10-day (laboratory) and 30-day (laboratory and field) exposures, trout were examined for several chemical, biochemical and histological endpoints. The results indicated that exposure to complex mixtures of chemicals, including estrogen receptor agonists, aryl-hydrocarbon receptor agonists, and probably antiandrogens, had occurred. Exposure altered the plasma levels of 17β-estradiol and testosterone, and some treatments also enhanced the activity of hepatic ethoxyresorufin O-deethylase. Gonadal histology showed varying levels of degenerative processes characterised by oocyte atresia, haemorrhages, melano-macrophage centres (MMCs), and oogonia proliferation. Liver histology showed less severe effects.  相似文献   
83.
The possible effects of a natural substance amygdalin and its combination with the mycotoxin deoxynivalenol (DON) on the steroid hormone secretion (progesterone and 17-β-estradiol) by porcine ovarian granulosa cells (GCs) were examined in this in vitro study. Ovarian GCs were incubated without (control group) and with amygdalin (1, 10, 100, 1,000 and 10,000 μg mL1), or its combination with DON (1 μg mL1) for 24 h. The release of steroid hormones was determined by ELISA. The progesterone secretion by porcine ovarian GCs was not affected by amygdalin in comparison to the control. However, the highest amygdalin dose (10,000 μg mL1) caused a significant stimulation of the 17-β-estradiol release. A combination of amygdalin with DON significantly (P < 0.05) increased the progesterone release at all concentrations. Similarly, a stimulatory effect of amygdalin co-administered with DON was detected with respect to the 17-β-estradiol secretion at the highest dose (10,000 μg mL1) of amygdalin and 1 μg mL1 of DON. Noticeable differences between the effects of amygdalin alone and its combination with DON on the progesterone release were detected. In contrast, no differences between the stimulatory effects of amygdalin and its combination with DON on the 17-β-estradiol synthesis by porcine GCs were observed. Findings from this in vitro study did not confirm the expected protective effect of amygdalin on mycotoxin induced reprotoxicity. Our results indicate that the stimulatory effect of amygdalin combined with DON on the progesterone release was clearly caused by the DON addition, not by the presence amygdalin per se. On the other hand, the stimulation of 17-β-estradiol production was solely caused by the presence of amygdalin addition. These findings suggest a possible involvement of both natural substances into the processes of steroidogenesis and appear to be endocrine modulators of porcine ovaries.  相似文献   
84.
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Dielectric barrier discharge (DBD) plasma applied as surface treatment technology was employed for the modification of Ag2O and graphitic carbon nitride (g-C3N4) powders. Subsequently, the pretreated powders were sequentially loaded onto TiO2 nanorods (TiO2-NRs) via electro-deposition, followed by calcination at N2 atmosphere. The results indicated that at the optimal plasma discharge time of 5 min for modification of g-C3N4 and Ag2O, photocurrent density of ternary composite was 6 times to bare TiO2-NRs under UV-visible light irradiation. Phenol was degraded by using DBD plasma-modified g-C3N4/Ag2O/TiO2-NRs electrode to analyze the photoelectrocatalytic performance. The removal rate of phenol for g-C3N4-5/Ag2O-5/TiO2-NRs electrode was about 3.07 times to that for TiO2-NRs electrode. During active species scavengers’ analysis, superoxide radicals and hydroxyl radicals were the main oxidation active species for pollutants degradation. A possible electron-hole separation and transfer mechanism of ternary composite with high photoelectrocatalytic performance was proposed.  相似文献   
85.
采用微波消解-ICP-OES法测定蔬菜中的镉,选择了最佳微波消解条件,确定了分析线.方法检出限为0.002 μg/L,相对标准偏差为1.1%,加标回收率为100%~104%,与干灰化法作对照试验,测定结果经t检验无显著差异.  相似文献   
86.
采用IRISER/SDuoICP测定马铃薯中的镉元素含量,并与火焰原子吸收法和石墨炉原子吸收法的测定作一比较,3种方法的检测限分别为0 001mg/L、0 004mg/L和0 25ng/L,加标回收率均在95%~102%范围内,相对标准差<10%。  相似文献   
87.
电感耦合等离子体质谱法测定地下水中痕量元素   总被引:1,自引:0,他引:1  
张建中  孙亦静 《干旱环境监测》2012,26(3):133-135,157
采用电感耦合等离子体质谱法(ICP-MS)同时测定地下水中痕量元素。结果表明,ICP-MS可同时测定地下水中的16种元素,方法检出限为0.02~0.2μg/L,元素的精密度(RSD,n=5)为1.46%~4.36%,加标回收率为96.6%~105.6%,符合环境监测无机组份测试质量控制的要求。该方法应用于直接测定元素浓度范围在ng/L~mg/L级的实际地下水样品,具有样品前处理简单、干扰少、测定快速、元素同时分析、省时省力等优点。  相似文献   
88.
等离子体汽车尾气治理技术   总被引:22,自引:0,他引:22  
等离子体技术应用于环境污染防治领域具有处理效率高、投资省、运行成本低、不产生二次污染等优点,已成功地运用于固体废物、废水和废气的治理,并成为近年来全世界广泛研究的课题。本文概述了汽车尾气治理技术的现状,探讨了等离子体处理废气的作用机理及其在汽车尾气治理中的应用,最后提出了等离子体处理汽车尾气技术在工业应用中尚需解决的问题。  相似文献   
89.
A cranial window method modified for our experiment enabled to observe the cerebral microcirculation including the blood-brain barrier permeability after a local expose to radio-frequency electromagnetic fields with a monopole antenna in rats. The present report reviews our recent publications that reported no noticeable changes in the cerebral microcirculatory parameters due to RF-EMF exposure.  相似文献   
90.
This work addresses the plasma treatment of two solid waste streams and production of fuel gases from the process. In this study, carpet waste and simulated solid wastes generated by a United States Air Force Basic Expeditionary Airfield Resources Base deployment were used. Waste was treated in a furnace fitted with a 100kW plasma arc torch. The off gas was analyzed to determine its composition. The product gas was composed primarily of carbon monoxide and hydrogen, with small amounts of methane, benzene and toluene also detected. These experiments demonstrate the feasibility of producing fuel gases by plasma treatment of the solid waste streams. While the thermal energy value of the fuel gas produced in these experiments was less than the energy input, a higher waste-to-fuel gas conversion efficiency is expected in full-scale application.  相似文献   
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