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81.
This study aims to investigate the effects of indoleacetic acid (IAA) and kinetin (Kn), which are plant growth regulators (PGRs), on antioxidant defense systems [reduced glutathione (GSH), glutathione-S-transferase (GST), catalase (CAT)], and lipid peroxidation level (malondialdehyde, MDA) various tissues of rats. Rats (Sprague-Dawley albino) were exposed to 100 ppm IAA and Kn. One hundred parts per million of PGRs was administered orally to rats ad libitum for 21 days continuously. The PGRs treatments caused different effects on the content of MDA and antioxidant defense system in comparison to those of control rats. According to the results, the subchronic treatments of IAA caused significant decrease in the GSH concentration and CAT activity in erythrocyte. Kn decreased GSH concentration in erythrocyte too. While the MDA concentration in brain was increased significantly by IAA and Kn, Kn decreased significantly brain CAT and GST activity. The liver GST activity was decreased by IAA and Kn. But, liver CAT activity was increased by IAA. On the other hand, while IAA treatment caused a significant decrease kidney GST activity, Kn caused a significant decrease both kidney GST and CAT activity. Also, while heart CAT activity was decreased by IAA, heart GST activity was decreased by both IAA and Kn. Moreover, MDA concentration in heart was increased by Kn treatment. It was concluded that IAA might effect MDA and antioxidant defense on the animals at subchronic treatment.  相似文献   
82.
83.
Specific plants can remove salts from the soil and contribute to saline remediation in orchard intercropping. Determining the level of highest salinity that a salt-removing crop can withstand without reducing its yield is important for management. It is also important to know the critical hazardous level of saline irrigation water for the fruit trees.The objective of this study was to investigate the salt-removing capacity of purslane by studying different stress criteria and by tracking its salt removal from germination to harvest. Therefore, a pot experiment was performed by enhanced salinity levels.The results showed that purslane could cumulatively remove considerable amounts of salt from the soil if practical to cultivate as an intercrop all year round. In this regard, 6.5 dS m−1 can be concluded as the reasonable salinity level for the purslane managed to be intercropped in fruit orchards.  相似文献   
84.
In this study, the electron paramagnetic resonance (EPR) spin probe technique is applied as a detection method in the differentiation of irradiated and unirradiated wheat seeds. Two wheat cultivars, Kunduru and Bezostaya, were used. Aqueous solutions of 4-hydroxy-TEMPO (TANOL) spin probe prepared with a line-broadening agent, potassium ferricyanide, were used in all experiments. The EPR spectra of the samples were recorded against time. A decrease in the signal intensity and a change in the shape of the intensity-time curve (rehydration curve) were observed, depending on the applied level of irradiation. The ratio of the lipid and aqueous regions at the high field (mI = -1) line changes, depending on the dose of irradiation.  相似文献   
85.
Citrus, especially K innow (Citrus deliciosa × Citrus nobilis), fruit yield and quality in Pakistan is not competitive with that of other countries which could be mainly attributed to the lack of good nutrient management for citrus orchards. The yield losses in this fruit crop occur mainly due to heavy fruit dropping. Experiments to overcome these problems were conducted at four different sites one each in Faisalabad, Toba Tek Singh, Jhang and Sargodha districts of Punjab, Pakistan. The soil and leaf chemical analysis showed severe deficiency of Zn and our pervious results have shown that soil amendment with potassium (K) at 75 K2O kg ha?1 improved the citrus fruit yield and quality at all selected sites. In the present experiments, effect of foliar application of Zn and K alone or in combination was studied on nutrient uptake, fruit yield, fruit dropping and juice quality. The fruit trees were pretreated with a selected K level of sulfate of potash (SOP) or muriate of potash (MOP), i.e., 75 kg K2O ha?1 along with recommended nitrogen (N) and phosphorus (P) doses. Zinc [Zn, 1% zinc sulfate (ZnSO4) solution], K [1% potassium sulfate (K2SO4) solution] and Zn + K (solution containing 0.5% each of ZnSO4 and K2SO4) were sprayed at the onset of spring and flush of leaves or flowers, fruit formation and at color initiation on fruit. Overall, application of Zn, K or Zn + K was effective in improving the nutrient uptake, yield and quality parameters of citrus fruit at all sites. Fruit dropping was also reduced by the foliar spray of Zn, K or Zn + K but the most promising results were recorded with foliar spray containing both Zn and K.  相似文献   
86.
This study was designed to investigate the effect of feeding on the plasma disposition of triclabendazole (TCBZ) in goats following oral administration. A total of eight goats, aged 14–16 months and weighing 20–30 kg were used in this study. The animals were allocated into two groups (fasted and fed groups) of four animals each. The goats in fed group were fed ad libitum but the animals in fasted group were not fed 24 h before and 6 h after drug administration. Commercial oral drench formulation of TCBZ (Endex-K, 5%) was administered orally to animals in two groups at dose of 10 mg/kg bodyweight. Heparinized blood samples were collected between 1 and 192 h after treatment and the plasma samples were analysed by high performance liquid chromatography (HPLC) for TCBZ, TCBZ sulphoxide (TCBZ–SO), and TCBZ sulphone (TCBZ–SO2). Relatively very low concentration of TCBZ parent drug was detected between 2 and 48 h, but TCBZ–SO and TCBZ–SO2 metabolites were present between 2 and 192 h in the plasma samples of fed and fasted animals. Fasting significantly enhanced the plasma concentration of TCBZ and its metabolites. The availability of TCBZ, TCBZ–SO and TCBZ–SO2 in the plasma samples of fasted goats were markedly greater compared to those of fed goats. It was concluded that fasting decreases the digesta flow rate and prolongs the retention of the drug into the gastrointestinal tract, resulting in enhanced quantitative gastrointestinal absorption or systemic availability of TCBZ and its metabolites in fasted goats.  相似文献   
87.
根据2008~2009年实地考察研究结果,着重就该区2种有蹄类动物的分布、种群数量以及有关问题作概要性探讨。调查研究结果表明:(1)老虎台盘羊分布区盘羊平均密度=8.49/8=1.06只/km^2,黑英山盘羊分布区盘羊平均密度=5.34/3=1.78只/km^2。整个分布区盘羊种群数量1 488只,其中,老虎台分布区种群数量=480×1.06=509只,黑英山分布区种群数量=550×1.78=979只。(2)老虎台北山羊分布区北山羊平均密度=14.59/5=2.92只/km^2,黑英山北山羊分布区北山羊平均密度=7.01/4=1.75只/km^2。整个分布区北山羊种群数量5 604只,其中,老虎台分布区种群数量=1 200×2.92=3 504只,黑英山分布区种群数量=1 200×1.75=2 100只。以上数据为该区2种野生有蹄类动物开展狩猎与保护提供了对策性依据。  相似文献   
88.
Plant Foods for Human Nutrition - This study aimed to optimize the extraction conditions for Sorbus umbellata (Desf.) Fritsch var. umbellata leaves to maximize the phenolic content and their...  相似文献   
89.
Angelwing clam were induced to spawn by thermal stimulation. Mature eggs measured 50 μm in diameter. Cell division occurred within 36 min after fertilization. Mobile trochophore larvae were seen after 12 h and larvae developed within 18 h. Reared on a diet of Isochrysis galbana the larvae reached the umbo stage in 6–7 days. On day 10 the foot could be seen and settlement occurred if a suitable substrate was present. The larvae completed metamorphosis into juveniles within 20 days after settling.  相似文献   
90.
Fucoidans are sulfated, complex, fucose-rich polymers found in brown seaweeds. Fucoidans have been shown to have multiple bioactivities, including anti-inflammatory effects, and are known to inhibit inflammatory processes via a number of pathways such as selectin blockade and enzyme inhibition, and have demonstrated inhibition of inflammatory pathologies in vivo. In this current investigation, fucoidan extracts from Undaria pinnatifida, Fucus vesiculosus, Macrocystis pyrifera, Ascophyllum nodosum, and Laminaria japonica were assessed for modulation of pro-inflammatory cytokine production (TNF-α, IL-1β, and IL-6) by human peripheral blood mononuclear cells (PBMCs) and in a human macrophage line (THP-1). Fucoidan extracts exhibited no signs of cytotoxicity in THP-1 cells after incubation of 48 h. Additionally, all fucoidan extracts reduced cytokine production in LPS stimulated PBMCs and human THP-1 cells in a dose-dependent fashion. Notably, the 5–30 kDa subfraction from Macrocystis pyrifera was a highly effective inhibitor at lower concentrations. Fucoidan extracts from all species had significant anti-inflammatory effects, but the lowest molecular weight subfractions had maximal effects at low concentrations. These observations on various fucoidan extracts offer insight into strategies that improve their efficacy against inflammation-related pathology. Further studies should be conducted to elucidate the mechanism of action of these extracts.  相似文献   
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