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51.
The levels of oxidative stress markers are an important indicator of the physiological state of the parasite and its host. In the present study levels of lipid peroxidation, glutathione S transferase, glutathione, superoxide dismutase and catalase were determined in the Clinostomum complanatum progenetic metacercaria, obtained from the fish peritoneum (a hypoxic habitat). The in vivo transformed ovigerous adult worms were obtained from the aerobic environment of the buccopharyngeal region of experimentally infected chickens. Levels of antioxidant molecules were also determined in the blood of experimentally infected chickens. An increase in the levels of lipid peroxidation, and a significant decrease in the levels of glutathione S transferase, glutathione, superoxide dismutase and catalase was observed in the infected host as compared to the controls. In the ovigerous worms, the levels of lipid peroxidation, glutathione S transferase, glutathione, superoxide dismutase were found to be significantly less than the levels observed in the progenetic metacercaria. Since the establishment of worm in the buccal cavity of the avian host would lead to its exposure to oxygen and the haematophagous nature of the parasite also exposes it to the free radicals in the host blood, the progenetic metacercaria has evolved to produce excess free radical scavenging molecules reserved to combat the oxidative stress encountered within the microhabitat of the definitive host.  相似文献   
52.
Sewage contains several trace elements of environmental concern, and cadmium (Cd) is one of the most mobile elements in soil–plant system that can pose drastic effects on plants and human health due to its long persistence and non-biodegradability nature in environment. It is necessary to prevent its entry into food chain for better food quality and human health. Present study was designed to evaluate the effectiveness of different water management practices, viz. W1: flooding throughout the growing season, W2: flooding after 4 days of disappearance of standing water (DAD), W3: flooding till heading and after that flooding of soil after 4 days of DAD, W4: Aerobic condition throughout growing season (flooding after 8 days) for reducing Cd concentration in rice grain grown under varying levels of Cd (0, 20, 40 mg kg?1) spiked soil. Results revealed that grain yield declined with increasing Cd levels but maximum plant height (89.3 cm), straw yield (16.9 g) and grain yield (22.5 g pot?1) was observed where pots were flooded till heading and thereafter flooding. Cadmium concentration increased with increasing concentration of Cd in soil. Further, it is added that the lowest Cd concentration in shoot, grain and husk and translocation factor were observed under W3 when the soil was spiked with 40 mg kg?1. In crux, continuous flooding till heading and thereafter flooding after 4 DAD can significantly decrease the grain Cd concentration without compromise on yield.  相似文献   
53.
Sahiwal cow is Bos indicus which is an important dairy breed of tropical and sub‐tropical region. Research on reproduction is rare in this breed. The objectives of the present study were to determine the effect of Ovsynch (OVS) versus prostaglandin F (PG) protocol on estrus response and its intensity, ovulation rate, timing of ovulation and pregnancy per artificial insemination (AI) in Sahiwal cows. Experimental cows (n = 80) were of mixed parity, lactating, suckled, ≥120 days postpartum with body condition score 3.08 ± 0.34 and 375‐475 kg of body weight which were randomly assigned to receive either OVS (n = 46) or PG (n =34) protocol. Cows were inseminated twice at 12 and 24 h after second gonadotropin releasing hormone in the OVS group, and 72 and 84 h after administration of prostaglandin F in PG group, respectively. The results revealed that estrus response did not differ (P > 0.05) and was 87% in OVS and 78% in PG cows. Ovulation rate did not differ (P > 0.05) and was 50% in both, OVS and PG cows. The pregnancy per AI did not differ (P > 0.05) and was 43% in OVS compared to 31% in PG cows. It is concluded that estrus response, ovulation rate and pregnancy per AI of OVS protocol is the same as PG in Sahiwal cows.  相似文献   
54.
Nawab  Javed  Khan  Nayab  Ahmed  Riaz  Khan  Sardar  Ghani  Junaid  Rahman  Ziaur  Khan  Fawad  Wang  Xiaoping  Muhammad  Juma  Sher  Hassan 《Journal of Soils and Sediments》2019,19(5):2417-2432
Purpose

Potentially toxic element (PTE) concentrations in mine-degraded soil and their bioaccumulation in food crops is a public health concern worldwide. The current study investigates the influence of organic geo-sorbents including biochar (B), farmyard manure (FYM), and peat moss (PTM) on PTE in chromite mine-degraded soil and their subsequent effects on spinach biomass, PTE uptake, average dietary intake (ADI), and health risk (HRI) associated with PTE via spinach consumption.

Materials and methods

Chromite mine-degraded soil samples were collected from different mining sites in Kohistan region. Pot experiments were carried out in the greenhouse environment. The selected geo-sorbents (B, FYM and PTM) were mixed at application rates of 1%, 2%, and 5%. Contaminated soil without geo-sorbents (control treatment) was also included in each batch of the experiments. Local FYM and PTM were used in this experiment, while B was provided by the Institute of Urban Environment (CAS) Xiamen, China. The total carbon (C), total nitrogen (N), and total sulfur (S) contents in mine-degraded soil and organic geo-sorbents were measured using a macro-elementor (VarioMax CNS, Germany). Total (acid digestion) and bioavailable PTE (As, Cd, Cr, Ni, Zn, and Pb) concentrations in mine-degraded soil and spinach were determined using inductive coupled plasma mass spectrophotometer (ICP-MS 7500 CX, Agilent Technologies, USA).

Results and discussion

The addition of organic geo-sorbents effectively immobilized the PTE concentrations in mine-degraded soil, and increased the major nutrient contents and thereby reduced the bioaccumulation of PTE (Cr, As, Ni, Cd, Zn, and Pb) in spinach. Consequently, B2, B5, FYM2, FYM5, PTM2, and PTM5 amendments significantly (p?<?0.001) increased the biomass, whereas the B1, FYM1, and PTM1 addition showed no significant increase in spinach biomass as compared to the control treatment. The results showed that all the organic geo-sorbents had significantly (p?<?0.001) reduced the As uptake in spinach, while B2, B5, FYM2, FYM5, and PTM5 significantly (p?<?0.001) decreased PTE bioaccumulation as compared to the control treatment.

Conclusions

The highest application rate (5%) showed the best result in increasing the spinach growth and biomass as well as reducing the PTE mobility in soil, and their bioaccumulation in spinach, as compared to 1% and 2% application rates and also with the control treatment. Furthermore, the average dietary intake (ADI) of PTE and health risk indices (HRIs) reduced via spinach consumption for both the children and adults, due to the addition of selected organic geo-sorbents used for soil amendments.

  相似文献   
55.
1. Seven 35-week-old Hubbard broiler breeder males were subjected to three semen collection frequencies either once every 2 d (48 h), daily (24 h) or twice daily (12 h). 2. Semen characteristics including motility, volume, concentration and sperm numbers per ejaculate were determined for each ejaculate. 3. Sperm motility was unaffected by collection interval, but semen volume was lower at 12 than 24h intervals. Sperm concentration was lower at 12 than 48h intervals. 4. At 24 and 48 h number of sperm per collection (1.7+/-0.2, 1.8+/-0.2 x 10(9)) were higher than at 12 h (1.2+/-0.1 x 10(9)). 5. The number of semen doses over a 6-d period increased linearly as the frequency of collection increased from once every 2 d to twice daily. 6. It is concluded that output was theoretically maximal at twice daily collection, but in practice not all cockerels may be able to maintain full performance with such a demanding regime.  相似文献   
56.
The effect on properties of starch isolated from Ajax and Diamant potatoes freshly harvested and irradiated immediately after harvest and after two weeks with 0.05, 0.10, 0.15, and 0.20 kGy were reported. Changes due to postirradiation storage up to six months at two different conditions (5 C, 90±2% RH and 20 C, 79±5% RH) were also studied. Swelling power (SP) slightly decreased or remained unchanged with different irradiation dose, but the effect of timing of irradiation after harvest was significant. Doses of 0.2 and 0.15 kGy significantly (p≤0.05) increased solubility, particularly at 90 C solubility temperature compared to lower doses. Decrease in viscosity with increasing dose immediately after irradiation was observed in both varieties but was more pronounced in Diamant. However, changes were dependent on variety, irradiation dose, timing of irradiation, and postirradiation storage conditions. Viscoamylograph test showed that 0.2 kGy significantly (p≤0.05) increased transmission temperature (TT) and temperature at maximum viscosity (TMV), but decreased the maximum viscosity immidiately after irradiation. The same trend was established during the post-irradiation storage time, particularly in Ajax starch, regardless of timing of irradiation or storage conditions. Thermoluminescence (TL) glow curves exhibited qualitative differences between irradiated and unirradiated tubers during the entire storage period, but dose estimation could not be determined.  相似文献   
57.
毛棉苗期抗旱性状的QTL定位   总被引:2,自引:1,他引:1  
【目的】通过分析毛棉苗期抗旱相关性状的数量性状位点(Quantitative trait locus,QTL),以期检测稳定的主效QTL,促进栽培品种抗旱性状遗传改良及提高抗旱育种效率。【方法】以四倍体野生种毛棉(Gossypium tomentosum)和陆地棉品种中棉所12(CCRI 12)的种间杂种F2及其F2:3家系为研究材料,用于基因型分型的F2有188个系,用于表型分型的F2:3家系有149个株系。分别在干旱胁迫和正常灌水2个环境下调查表型数据。采用复合区间作图法对F2:3家系苗期相关性状抗旱系数进行QTL定位。【结果】对苗期相关性状抗旱系数的QTL定位分析,共得到16个QTL,其中与株高、叶片数、叶绿素含量、脯氨酸含量、丙二醛含量抗旱系数相关的QTL分别有5个、1个、3个、3个、4个,分布在13条染色体上。来自毛棉的5个加性QTL分别为qSHDC-19-1、qSHDC-19-2、qSLNDC-5-1、qMDADC-24-1、qMDADC-24-2,其加性效应值为0.10~0.22,解释变异9.4%~25.8%。【结论】这些与抗旱相关的QTL有助于棉花抗旱分子标记辅助选择。  相似文献   
58.
Ammonium‐N concentrations were frequently observed to exceed nitrate‐N concentrations in an intermittently flowing stream draining acid grassland in North Yorkshire. This prompted the design of a soil microcosm experiment to investigate the role of litter in the leaching of ammonium and nitrate from soil profiles during winter. Drainage water was analysed weekly for N species, pH, mineral acid anions and dissolved organic carbon (DOC) for a period of 11 weeks, while extractable mineral‐N was determined after 5 and 11 weeks. The results demonstrate that litter plays an important role in reducing mineral‐N leaching in winter months. They also suggest that DOC from the litter participates in mineral‐N retention in the soil profiles in winter. Ammonium‐N and nitrate‐N concentrations measured in the microcosm drainage water are similar to those of the stream.  相似文献   
59.
60.
Ursene type nortriterpene from Debregeasia salicifolia   总被引:1,自引:0,他引:1  
Akbar E  Riaz M  Malik A 《Fitoterapia》2001,72(4):382-385
A new triterpene, 3beta-19alpha-dihydroxy-30-norurs-12-ene (1), has been isolated from the methanolic extract of Debregeasia salicifolia stems. Its structure has been elucidated with the help of one- and two-dimensional NMR and NOE studies. Lupeol, beta-sitosterol, stigmasterol and oleanolic acid are also reported for the first time from this species.  相似文献   
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