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1.
This study examined the effects of chlorpyrifos in the rat erythrocyte antioxidant system and evaluated the ameliorating effects of catechin and quercetin on the oxidative damage induced by chlorpyrifos. Sexually mature male Wistar rats were given chlorpyrifos (5.4 mg/kg, 1/25 of the oral LD50), catechin (20 mg/kg), quercetin (20 mg/kg), catechin plus chlorpyrifos, and quercetin plus chlorpyrifos daily via gavage for four weeks. No statistical differences were found in the catechin-only and quercetin-only groups compared with the control group. By the end of the fourth week, chlorpyrifos alone increased the levels of malondialdehyde (MDA) and decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities compared with the control group in rat erythrocytes. In the catechin-plus-chlorpyrifos and quercetin-plus-chlorpyrifos groups, there were statistically significantly decreased MDA levels and increased SOD, CAT, and GPx activities compared with the chlorpyrifos-only group. Thus, it appears that catechin and quercetin ameliorate chlorpyrifos-induced oxidative stress in rat erythrocytes in vivo.  相似文献   
2.
营养液浓度直接影响着水培蔬菜的产量与品质。本试验研究不同浓度的营养液处理对水芹生长品质和产量的影响, 以筛选适宜温室水培水芹生长的营养液浓度。结果表明:随着营养液浓度的增加,水芹生物量、叶绿素含量、光合参数、总 黄酮、VC、可溶性蛋白含量等指标呈现先升高后降低的趋势,其中1.5 倍营养液浓度处理表现最佳,能够提高水芹整体品 质与产量。  相似文献   
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4.
In this study was evaluated potential protective effect of organic selenium (Se) on heavy metal stress induced by lead (Pb) in Cyprinus carpio. For this reason, C. carpio was exposed to sublethal concentration of Pb (1.5 mg/L Pb(NO3)2) for 14 days. The fish were fed a basal (control; measured 0.55 mg/kg Se) diet or a basal diet supplemented with 2.50 mg/kg (measured 2.92 mg/kg Se) organic Se (Sel-Plex®) during the experiment period. The variations in glutathione peroxidase (GSH-Px), glutathione S-transferase (GST) activities, and levels of reduced glutathione (GSH) with malondialdehyde (MDA) in liver and brain tissues of C. carpio were investigated in experimental groups. GSH levels in liver and brain tissues were significantly decreased by exposure to Pb. GST activity was significantly increased (p < 0.05) in liver tissue, but decreased in brain of treated fish by exposure to Pb. Also, GSH-Px activity was significantly increased in liver tissue, but decreased in brain of Pb-treated fish. Levels of MDA were increased in liver and brain of Pb-treated fish. The organic Se treatment for Pb-intoxicated animals improved activities of GSH-Px, GST and levels of MDA within normal limits. Supplemented Se could be able to improve Pb-induced oxidative stress by decreasing lipid peroxidation and regulating antioxidant defense system in tissues.  相似文献   
5.
Experiments were designed to investigate the size distribution of queen steroidogenic luteal cells throughout pseudopregnancy. Corpora lutea were obtained from the queens following ovariohysterectomy on days 7, 15 or 25 of pseudopregnancy. Luteal cells were isolated from the ovary by collagenase digestion. Steriodogenic cells were identified by staining of cells for 3β-HSD activity. Cell diameters were measured using a microscope. Luteal cells having steroidogenic capacity covered a wide spectrum of sizes ranging from 3 to 35 μm in diameter. There was a significant increase in mean cell diameters (p < 0.01) as pseudopregnancy progressed. Mean diameter of 3β-HSD positive cells increased from 10.41 ± 0.7 μm, on day 7 of pseudopregnancy, to 19.72 ± 1.3 μm on day 25 of pseudopregnancy. The ratio of large (>20 μm in diameter) to small (3–20 μm in diameter) luteal cells was 0.08 : 1.0 on day 7 of pseudopregnancy, with the 7.5–10 μm cell size class predominant. By day 25 of pseudopregnancy, the ratio of large-to-small cells was increased to 0.87 : 1.0, and 20–25 μm cell sizes become predominant. In conclusion, this study has demonstrated that the cells of the corpus luteum undergo continuous differentiation during pseudopregnancy in queen. This study also demonstrates that luteal cells dissociated from pseudopregnant queen can be used as a model to study the physiology of corpus luteum in pregnant cats.  相似文献   
6.
采用ISSR分子标记技术,分析78份杧果种质的遗传多样性。从100条引物中筛选出12条优选引物,共扩增出148条DNA条带,其中多态性带142条,多态性百分率为95.95%。聚类分析结果将78份杧果种质分为5大类。在5大类资源中,大部分种质(87.34%)都聚在第Ⅰ类,表明大部分杧果种质之间亲缘关系较近,供试种质之间能互相区分开来并表现出丰富的遗传多样性。  相似文献   
7.
Blood samples collected from 945 cattle at four local abattoirs in Turkey were examined for contagious bovine pleuropneumonia (CBPP) by the complement fixation test (CFT) and competitive ELISA (cELISA). In addition, the carcases of the animals were examined macroscopically at the abattoirs and 62 lung samples which had lesions suggestive of CBPP were collected for bacteriological culture. To identify suspicious isolates the PCR was used in addition to the routine biochemical tests. By the CFT, two of the 945 serum samples were seropositive, and by the cELISA, four of them were seropositive. In the bacteriological culture of the lungs, growth was observed in 18 (29 per cent) of the samples by the observation of turbidity in the broths. However, when these broths were inoculated into an agar base, growth was observed in only three (4.8 per cent) samples. These isolates were identified as Mycoplasma species on the basis of biochemical tests. In the PCR analysis of DNA extracted from the broths, none of the isolates was identified as Mycoplasma mycoides subspecies mycoides small colony or one of the members of the M mycoides cluster, but amplification was obtained in only eight (44.4 per cent) of 18 samples, using Mycoplasma-genus specific primers. These DNA samples were examined further with primers specific to 16S rRNA and were then sequenced and compared with the databanks; DNA homologies at different levels were observed in five samples, with Mycoplasma alkalescens, Mycoplasma canadense, Mycoplasma bovis and Mycoplasma bovigenitalium.  相似文献   
8.
Diazinon is an organophosphate insecticide has been used in agriculture and domestic for several years. Vitamin E (200 mg/kg, twice a week), diazinon (10 mg/kg, per day), and vitamin E (200 mg/kg, twice a week)+diazinon (10 mg/kg, per day) combination was given to rats orally via gavage for 7 weeks. Body and heart weights, malondialdehyde (MDA) level in heart tissue and ultrastructural changes in myocardial cells were investigated at the end of the 1st, 4th, and 7th weeks comparatively with control group. When diazinon-treated group was compared to control group body and heart weights were decreased significantly at the end of the 4th and 7th weeks. It was observed that, at the end of 1st, 4th, and 7th weeks there was a statistically significant increase in MDA levels when diazinon- and vitamin E +diazinon-treated groups were compared to control group. While at the end of the 1st week statistically significant changes were not being observed, at the end of 4th and 7th weeks statistically significant decrease was detected in MDA levels when vitamin E+diazinon-treated group was compared to diazinon-treated group. In our electron microscopic investigations, while vacuolization and swelling of mitochondria myocardial cells of diazinon-treated rats were being observed, swelling of several mitochondria were observed in vitamin E+diazinon-treated rats. We conclude that vitamin E reduces diazinon cardiotoxicity, but vitamin E does not protect completely.  相似文献   
9.
Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and kidney weights, malondialdehyde (MDA) levels and histopathological changes were investigated at the end of 4th and 7th weeks comparatively with control group. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group body and kidney weights decreased significantly at the end of 4th and 7th weeks. MDA levels increased in kidney tissues of the methyl parathion- and vitamins C and E + methyl parathion-treated groups compared to control group. MDA levels decreased significantly in vitamins C and E + methyl parathion treated group compared with methyl parathion treated group at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 weeks of methyl parathion exposure, glomerular atrophy and vascular dilatation, and after 7 weeks, necrosis and edema were observed in the kidney tissues. After 4 weeks of vitamins C and E + methyl parathion exposure, mononuclear cell infiltrations, and after 7 weeks, calcification were detected in the kidney tissues.  相似文献   
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