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61.
David E. Kime Mohammad A. S. Abdullah Miroslawa Sokolowska-Mikolajczyk Piotr Epler 《Fish physiology and biochemistry》1994,13(4):317-324
Carp ovarian tissue was incubated with 3H-17-hydroxyprogesterone in the presence of 0, 0.1, 1, 10, and 100 μg ml−1 unlabeled 17-hydroxyprogesterone. The pattern of metabolites formed showed a marked variation with substrate concentration.
Formation of glucuronide and sulphate conjugates was important only at low substrate concentration. At high substrate concentration
(10 and 100 μg ml−1) 17,20α-dihydroxy-4-pregnen-3-one was the major metabolite, but at intermediate concentrations polar 7α-hydroxypregnanetetrols
predominated. The results support the hypothesis that at low substrate concentrations conjugating, 5α-reducing and 7α-hydroxylating
enzymes, of high activity but low capacity, act as scavengers to deactivate any steroids formed during the relatively low
pituitary gonadotrophin secretions which are necessary for oocyte development, but that during the prespawning gonadotrophin
surge when high levels of substrate are present these enzymes are saturated and 17,20α-dihydroxy-4-pregnen-3-one (17,20αP)
becomes the major ovarian steroid. The possible role of 17,20αP during oocyte final maturation requires further examination. 相似文献
62.
Marine sponges belonging to the phylum Porifera (Metazoa), evolutionarily the oldest animals are the single best source of marine natural products. The present review presents a comprehensive overview of the source, taxonomy, country of origin or geographical position, chemical class, and biological activity of sponge-derived new natural products discovered between 2001 and 2010. The data has been analyzed with a view to gaining an outlook on the future trends and opportunities in the search for new compounds and their sources from marine sponges. 相似文献
63.
Fayaz Humara Mir Asma Hamid Tyagi Sandhya Wani Aijaz A. Jan Nelofar Yasin Mohammad Mir Javid Iqbal Mondal Biswajit Khan Mohd Anwar Mir Reyazul Rouf 《Genetic Resources and Crop Evolution》2022,69(3):1193-1205
Genetic Resources and Crop Evolution - Cicer arietinum L. (chickpea) is one of the most significant legume crops domesticated in the Fertile Crescent. This study was aimed to characterize a diverse... 相似文献
64.
Cécile Stanford Jia-Qian Jiang Mohammad Alsheyab 《Water, air, and soil pollution》2010,209(1-4):483-488
This paper presents a comparative study of the performance of ferrate(VI), FeO 4 2? , and ferric, Fe(III), towards wastewater treatment. The ferrate(VI) was produced by electrochemical synthesis, using steel electrodes in a 16 M NaOH solution. Domestic wastewater collected from Hailsham North Wastewater Treatment Works was treated with ferrate(VI) and ferric sulphate (Fe(III)). Samples were analysed for suspended solids, chemical oxygen demand (COD), biochemical oxygen demand (BOD) and P removal. Results for low doses of Fe(VI) were validated via a reproducibility study. Removal of phosphorous reached 40% with a Fe(VI) dose as low as 0.01 mg/L compared to 25% removal with 10 mg/L of Fe(III). For lower doses (<1 mg/L as Fe), Fe(VI) can achieve between 60% and 80% removals of SS and COD, but Fe(III) performed even not as well as the control sample where no iron chemical was dosed. The ferrate solution was found to be stable for a maximum of 50 min, beyond which Fe(VI) is reduced to less oxidant species. This provided the maximum allowed storage time of the electrochemically produced ferrate(VI) solution. Results demonstrated that low addition of ferrate(VI) leads to good removal of P, BOD, COD and suspended solids from wastewater compared to ferric addition and further studies could bring an optimisation of the dosage and treatment. 相似文献
65.
Prolific and rapid in vitro plant organogenesis via direct regeneration has been obtained from axenic seedling-derived petiole and leaf explants of Ficus religiosa in Murashige and Skoog (MS) medium containing different concentrations of cytokinins in combination with indole-3-butyric acid (IBA). MS medium with 1.5 mg/l 6-benzylaminopurine plus 0.15 mg/l IBA produced the highest shoot induction frequency with an average of 6.26 and 10.13 shoots per leaf and petiole explants, respectively. After 4 weeks, the highest root formation frequency (96.7%), root number (5.73), and root length (4.76 cm) were with MS medium containing 2.0 mg/l IBA plus 0.1 mg/l α-naphthalene acetic acid. In addition, the effect of four sodium nitroprusside (SNP) treatments on acclimatization was also studied. Highest morphological traits such as survival rates, fresh and dry root weights as well as antioxidant enzymatic activities such as superoxide dismutase, peroxidase, and catalase was achieved with 125 ppm SNP. The α-amino acid, proline, content was highest with this treatment while the highest H2O2 (hydrogen peroxide) was in the controls. This study introduces a cost-effective, prolific, and efficient in vitro multiplication system to supply pharmaceutical and ornamental needs. It is the first report of an in vitro organogenesis protocol for F. religiosa by direct regeneration through axenic seedling-derived petiole and leaf explants, which can be efficiently employed for the utilization of active biomolecules. 相似文献
66.
Mohammad Mehdi Oloumi Dariush Vosough Amin Derakhshanfar Mohammad Hadi Nematollahi 《Journal of Equine Veterinary Science》2011,31(8):470-474
This study was carried out to evaluate the healing potential of water-soluble extract of Plantago lanceolata as a topical ointment on experimental tendinitis in burros. Tendinitis was induced by injection of 2,500 U of bacterial collagenase in the superficial digital flexor tendon of both forelimbs of six male burros. Tendinitis was confirmed ultrasonographically. 48 hours after collagenase injection, two grams of 10% P lanceolata ointment was applied on one limb (treatment group) and the same amount of eucerin (the vehicle of the ointment) on the other limb (control group), every other day for 6 weeks. Ultrasonographic examination of the tendon was performed weekly during the study and mean cross-sectional area of the superficial digital flexor tendon was measured, which was found to increase significantly after injection of collagenase in both groups. From the third week, it decreased significantly in the treatment group in comparison with the control group. At the end of the study, the animals were euthanized for histopathological study of the tendons. In control group, degenerative changes in tendon could be seen, whereas significant degree of healing was observed in the treatment group. It can thus be concluded that the P lanceolata ointment was effective in promoting the healing process of the tendon. 相似文献
67.
R. W. Skaggs M. A. Brevé A. T. Mohammad J. E. Parsons J. W. Gilliam 《Irrigation and Drainage Systems》1995,9(3):259-277
The design and management of drainage systems should consider impacts on drainage water quality and receiving streams, as well as on agricultural productivity. Two simulation models that are being developed to predict these impacts are briefly described. DRAINMOD-N uses hydrologic predictions by DRAINMOD, including daily soil water fluxes, in numerical solutions to the advective-dispersive-reactive (ADR) equation to describe movement and fate of NO3-N in shallow water table soils. DRAINMOD- CREAMS links DRAINMOD hydrology with submodels in CREAMS to predict effects of drainage treatment and controlled drainage losses of sediment and agricultural chemicals via surface runoff. The models were applied to analyze effects of drainage intensity on a Portsmouth sandy loam in eastern North Carolina. Depending on surface depressional storage, agricultural production objectives could be satisfied with drain spacings of 40 m or less. Predicted effects of drainage design and management on NO3-N losses were substantial. Increasing drain spacing from 20 m to 40 m reduced predicted NO3-N losses by over 45% for both good and poor surface drainage. Controlled drainage further decreases NO3-N losses. For example, predicted average annual NO3-N losses for a 30 m spacing were reduced 50% by controlled drainage. Splitting the application of nitrogen fertilizer, so that 100 kg/ha is applied at planting and 50 kg/ha is applied 37 days later, reduced average predicted NO3-N losses but by only 5 to 6%. This practice was more effective in years when heavy rainfall occurred directly after planting. In contrast to effects on NO3-N losses, reducing drainage intensity by increasing drain spacing or use of controlled drainage increased predicted losses of sediment and phosphorus (P). These losses were small for relatively flat conditions (0.2% slope), but may be large for even moderate slopes. For example, predicted sediment losses for a 2% slope exceeded 8000 kg/ha for a poorly drained condition (drain spacing of 100 m), but were reduced to 2100 kg/ha for a 20 m spacing. Agricultural production and water quality goals are sometimes in conflict. Our results indicate that simulation modeling can be used to examine the benefits of alternative designs and management strategies, from both production and environmental points-of-view. The utility of this methodology places additional emphasis on the need for field experiments to test the validity of the models over a range of soil, site and climatological conditions. 相似文献
68.
Mohammad H. Ahmad Amani M. D. El Mesallamy Fatma Samir Faten Zahran 《Journal Of Applied Aquaculture》2013,25(4):289-298
Four isonitrogenous (30% crude protein) and isocaloric (4.40 kcal/g) experimental diets were formulated to contain 0.0% (control), 0.5%, 1.0%, or 1.5% cinnamon. The diet containing 1% cinnamon resulted in significantly greater (P < 0.05) specific growth rate (SGR), feed conversion ratio (FCR), feed efficiency ratio (FER), protein efficiency ratio (PER), apparent protein utilization (APU), and energy utilization (EU). In regard to body composition, there was no significant difference in dry matter, protein, lipids, and ash (P > 0.05) contents due to cinnamon supplementation. Blood plasma profile showed an improvement in hemoglobin (HB), red blood cell (RBCS), hematocrite (PCV), total protein, and total lipids, while there was a decrease in creatinin, urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glucose in fish fed 1% cinnamon. Cinnamon was found to have an antibacterial activity antagonistic to Aeromonas hydrophila infection in fish. Performance and FCR improvement translated into a 10% decrease in feed costs associated with the 1% cinnamon diet. 相似文献
69.
Abbas Rajaeerad Gholam R. Ghorbani Mohammad Khorvash Ali Sadeghi-Sefidmazgi Amir H. Mahdavi Mirja R. Wilkens 《Journal of animal physiology and animal nutrition》2021,105(1):14-25
This study investigated the effects of low potassium diets with different levels of Ca compared to two diets low in dietary cation–anion difference (DCAD) fed prepartum as a strategy to prevent hypocalcemia on sorting behaviour, total tract digestibility, oxidative status and energy and protein metabolism of transition cows. Forty-eight pregnant dairy cows were assigned to 4 treatment groups: Low Ca, low K (LCLK), High Ca, low K (HCLK), Supplementation with anionic mineral mixture (AMS) supplementation with SoyChlor (CAS). After parturition, all animals were fed a standard postpartum diet. Data were collected until 21 DIM. Prepartum urinary pH was significantly reduced by the low DCAD diets, while postpartum Ca homeostasis was affected by the HCLK ration. Feeding AMS induced sorting against particles <1.18 mm in favour of particles >19 mm prepartum. In contrast, cows fed CAS showed an increase in selective consumption of fine particles and sorted against longer particles similar to the HCLK and LCLK groups. Postpartum sorting activity was not affected by the dietary treatments. After calving, apparent digestibility of NDF was significantly reduced in the HCLK group. Prepartum, we observed effects on serum concentrations of non-esterified fatty acids were higher and insulin sensitivity was lower in the AMS group. Blood urea nitrogen (BUN) was decreased in cows fed the CAS ration. Postpartum, we found serum protein to be decreased with the low DCAD diets while BUN was decreased in the CAS group. The low DCAD rations increased prepartum serum malondialdehyde concentrations, while postpartum total antioxidant capacity was lower in the HCLK and the AMS group. From these data, we conclude that AMS decreased prepartum intake due to compromised palatability. Intermediate protein metabolism was affected by the low DCAD diets, while parameters of oxidative stress were probably affected by acid–base balance and Ca homeostasis. 相似文献
70.
Sarabi Hamzeh Jafari Pilehvar Babak Vajari Kambiz Abrari Waez-Mousavi Seyed Mohammad 《European Journal of Forest Research》2021,140(6):1377-1390
European Journal of Forest Research - Many studies have been conducted on the effects of changes in plant diversity and species composition on ecosystem functioning and plant productivity due to... 相似文献