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11.
RNA编辑是陆生植物叶绿体转录后基因表达调控的一种重要方式。为进一步探讨单子叶植物RNA编辑功能及其发生机制,本研究通过生物信息学方法,对二穗短柄草叶绿体的81个蛋白编码基因的RNA编辑位点进行了预测和鉴定分析,结果发现78个基因存在编辑位点,共检测到176个编辑位点,都是C到U的转换。其中ndhB最多,为14个编辑位点。为验证预测结果,利用blast工具比对了NCBI的二穗短柄草EST数据库,最终确定存在于17个基因中的34个编辑位点是真实存在的,其中19个为沉默编辑,15个为有效编辑。与5个不同单子叶禾本科物种18个蛋白编码基因的RNA编辑位点的比较发现,在rpoB-206位点,只有二穗短柄草发生了编辑,且只有ndhD-295(293)为部分编辑位点。 相似文献
12.
Parishmita Handique Hemanta Pokhrel Binod Kalita Raktim Sarmah Abdul Malik Ahmed Kaustabh Bhagawati Arnab Narayan Patowary 《Aquaculture Research》2020,51(5):1973-1979
The present study was conducted to evaluate the …effect of dietary selenium on growth performance and antioxidant enzymes activity in Cirrhinus mrigala for a period of 45 days. Four numbers of experimental diets were prepared, Tc for Control (0 mg organic selenium/kg of diet), T1 (2.5 mg organic selenium/kg of diet), T2 (5.0 mg organic selenium/kg of diet) and T3 (10 mg organic selenium/kg of diet). The water quality parameters (temperature, DO, pH, conductivity, hardness, ammonia, nitrate and nitrite) were found to be insignificant (p > .05) among all the treatments. Superoxidase dismutase (SOD) was found to be significantly highest in T2 (6.10 ± 0.07) when compared with the other treatments. Similarly, catalase (CAT) activity in T1 (13.21 ± 0.13) was significantly (p < .05) different with that of Control, T2 and T3. Present study also revealed that 2.5mg organic selenium/kg supplemented diet (T1) showed highest results in net weight gain (15.55 ± 1.36 g), net weight gain percentage (185.88 ± 8.98%) and SGR (2.35 ± 0.06 g) compared with other experimental diet. 相似文献
13.
Md. Abdul Kader Shunsuke Koshio Manabu Ishikawa Saichiro Yokoyama Mahbuba Bulbul Binh Thanh Nguyen Jian Gao Asda Laining 《Aquaculture Research》2012,43(10):1427-1438
An experiment was carried out to evaluate fermented soybean meal and squid by‐product blend (1:1) (FP) as replacement of fishmeal (FM) for Japanese flounder, Paralichthys olivaceus. Five isocaloric (19 kJ g?1) diets were prepared by replacing 0 (FP0), 12 (FP12), 24 (FP24), 36 (FP36) and 48% (FP48) FM protein with FP. Triplicate groups of juveniles (mean weight of 3.9 g) were delivered the test diets for 8 weeks in a flow‐through sea water system. The results showed that there were no significant differences (P > 0.05) among the growth rates of fish fed FP0, FP12, FP24 and FP36 diets. Growth and nutrient utilization parameters were significantly reduced in fish fed FP48 diet. Although, whole body proximate composition of fish were not significantly affected by the dietary treatments compared to the control; methionine and phenylalanine contents were significantly decreased in FP48 group. Protein retention was also significantly decreased in the similar group of fish. Dietary treatments did not alter most of the plasma metabolites, while some of the health parameters were improved in the replacement groups. Results suggested that FP is a potential candidate for alternative protein ingredient in aquafeed and can replace 36% FM protein in the diet of Japanese flounder. 相似文献
14.
Effect of thermal stress on Hsp70 gene expression and female reproductive performance of giant freshwater prawn,Macrobrachium rosenbergii 下载免费PDF全文
Using Hsp70 as a biomarker, thermal stress impinges on reproductive organs, ovary and hepatopancreas were being analyzed by determining the expression of Hsp70 mRNA inside the organs after the adult inter‐molt females were subjected to thermal treatment at 35, 30 and 28°C (Control). Results showed the expression of Hsp70 mRNA under thermal treatment of 35°C after 2 hr recovery in ovary were upregulated at 2, 4, 6, 12, 24 hr and 30 days compared to control whereas in hepatopancreas under similar treatment, the expression of Hsp70 mRNA were significantly higher than control at 6, 24 hr and 30 days. Frequency of reproductive molt at 35°C showed the ovary of females were failed to develop and only entered common molt along three consecutive molt cycles. For 30°C thermal treatment, the expression of Hsp70 mRNA was significantly higher than control after 2 hr recovery but returned to normal afterwards until 30 days’ thermal treatment. Maternal heat shock for 2 hr at 35°C were found to give significantly lower frequency of reproductive molt and longer duration of ovarian development and incubation period whereas maternal heat shock for 2 hr at 30°C gave lower frequency of reproductive molt, slower development of embryo and lower hatching success compared to untreated control. This study suggests that short and long‐term thermal stress at 30 and 35°C were found to affect the induction of Hsp70 mRNA in reproductive organs of Macrobrachium rosenbergii and also influence their reproductive performance. 相似文献
15.
Md Asaduzzaman Shumpei Iehata Md Moudud Islam Md Abdul Kader Abol‐Munafi Ambok Bolong Daisuke Ikeda Shigeharu Kinoshita 《Aquaculture Nutrition》2019,25(6):1300-1317
This study investigated the effects of sodium alginate supplementation on gut microbiota composition, health parameters, growth performances and growth‐related gene expression of Malaysian mahseer. Five test diets were formulated by supplementing 0%, 0.1%, 0.2%, 0.4% and 0.8% sodium alginate. Triplicate groups of juvenile Tor tambroides (2.19 ± 0.05 g) were stocked in 15 aquaria (20 individuals per aquarium) and fed at 3.0% body weight per day for 60 days. PCoA and UPGMA analysis showed that gut bacterial community were more convergence in higher sodium alginate‐supplemented diets. The percentage of Porphyromonadaceae, Bacteroides, Plesiomonas and Shewanella were substantially higher and Aeromonas, Entomoplasmatales and Prevotellaceae were drastically lower in higher sodium alginate (0.2%–0.8%) diets. Sodium alginate supplementation (≥0.2%) significantly improved the haematocrit value and respiratory burst activity of T. tambroides. Growth performances and feed utilization were significantly higher in 0.2%–0.4% sodium alginate‐supplemented diets. The increased growth rate of T. tambroides was governed by both hyperplastic and hypertrophic muscle growth. Real‐time PCR data demonstrated that most of the growth‐related genes were significantly upregulated in 0.2%–0.4% sodium alginate‐supplemented diet. Finally, it can be concluded that sodium alginate should be supplemented at 2 g/kg in practical fish feed formulation. 相似文献
16.
Effect of high inclusion of rendered animal by‐product ingredients on growth,digestibility and economic performances in climbing perch Anabas testudineus 下载免费PDF全文
Md Sakhawat Hossain Md Abdul Kader Tanwi Dey Nadia Mahjabin Sony Mahbuba Bulbul Shunsuke Koshio 《Aquaculture Research》2017,48(3):931-940
A 70‐day growth trail was conducted to investigate the effects of inclusion of high levels of meat and bone meal (MBM) and protein concentrate (PC) on growth, digestibility and economic performances of climbing perch, Anabas testudineus. Four isonitrogenous diets were formulated by lowering the level of dietary fishmeal protein at 0 (D1, control), 70 (D2), 85 (D3) and 100% (D4) with a mixture of MBM and PC protein (1:1). Triplicate groups of 300 fish (mean weight of 0.80 g) stocked in each 40 m2 pond and fed the respective test diets. A digestibility trial was conducted after the growth trial in indoor glass aquarium. The result showed that growth parameters were significantly decreased (P < 0.05) with fishmeal replacement levels. However, significant differences were not found in feed conversion ratio and survival of fish. No difference was also found in protein efficiency ratio among D1, D2 and D3. Similar to growth parameters, total fish production was highest in D1, intermediate in D2 and D3; and lowest in D4. Apparent digestibility coefficients of dry matter, protein and lipid were highest (P < 0.05) in D1 and lowest in D4. The economic analysis revealed that the benefit cost ratio was ranked by D3 (1.81), D2 (1.71), D1 (1.66) and D4 (1.46) respectively. Upon considering the overall performances and unavailability of finite protein sources, it can be concluded that 70–85% fishmeal could be replaced with a mixture of MBM and PC (1:1) in practical diets for climbing perch. 相似文献
17.
Neurotoxicity complicates the use of several commonly administered chemotherapeutic agents (platinum based alkylating agents, taxanes and vinca alkaloids), with chemotherapy-induced peripheral neuropathy being the most common manifestation. Structural damage to the peripheral nervous system results in positive symptoms, e.g., allodynia, hyperalgesia and pain with unpleasant features as burning and shooting. Patients are unable to complete full or optimal treatment schedules. The pathophysiologic basis of nerve injury in chemotherapy-induced peripheral neuropathy is incompletely understood and appears to be unique for each class of the chemotherapeutic agents. Erythropoeitin (EPO), a well-established hematopoietic factor, is a very effective and widely used treatment for anemia in cancer patients undergoing chemotherapy. It also possesses generalized neuroprotective and neurotrophic properties. Co-treatment of chemotherapy and erythropoietin has been proposed for preventing or reversing the disabling peripheral neuropathy induced by the different chemotherapeutic agents. This study first describes the pathophysiological background of the clinically relevant chemotherapeutic agents-inducing peripheral neuropathy. Secondly, the possible mechanisms that might underlie the neuroprotective effect of erythropoietin in chemotherapy-induced neuropathy. Further clinical trials of EPO in cancer patients receiving chemotherapy and suffering from neurological symptoms seem to be warranted in the future. This might improve the quality of life in cancer patients. 相似文献
18.
Md Abdul Wahab Sk Ahmad‐Al‐Nahid Nesar Ahmed Mohammad M Haque Mahmudul Karim 《Aquaculture Research》2012,43(7):970-983
Giant river prawn (Macrobrachium rosenbergii) farming plays an important role in the economy of Bangladesh. Presently, it is cultured in around 50 000 ha area with total annual production of 23 240 t. Traditional extensive prawn farming has been expanding over the last three decades through the introduction and adoption of improved culture systems, such as culture of prawn‐carps, prawn‐shrimp‐fish and prawn‐fish‐rice as concurrent and rotational systems. Efforts for the development of improved techniques on broodstock management, seed production and rearing and grow‐out of prawn have been made over the last decade. The outcomes are low‐cost feed for broodstock, production of post‐larvae in net cages (hapa), all‐male prawn culture, periphyton based prawn‐tilapia culture, C/N based prawn culture, organic prawn farming, prawn‐mola culture and prawn‐carp‐mola polyculture. Despite the development of culture technologies, a number of challenges for sustainable development of prawn farming need to be overcome to realize the potentials of this promising sector. Good aquaculture practises at all levels and application of measures for quality control and food safety would ensure sustainable development of prawn farming in Bangladesh. 相似文献
19.
Habsah A. Kadir Muhamad B. Zakaria Abdul A. Kechil Moh D. S. Azirun 《Pest management science》1989,25(4):329-335
The potential insecticidal activity of Spilanthes acmella Murr. (Compositae) extracts was assessed in this study. The extracts were shown to be toxic against adults of American cockroach, Periplaneta americana L. The active component in S. acmella extract was isolated and identified as N-isobutyl-2,6,8-decatrienamide (spilanthol). The results from topical application of spilanthol show that it has a high acute toxicity and spilanthol was the most potent compound when compared to three conventional insecticides. The potency was found to be 1.3, 2.6 and 3.8 times more toxic than carbaryl, bioresmethrin and lindane, respectively. Electrophysiological studies indicated immediate hyperexcitation followed by complete inhibition of the cockroach cercal nerve activity. 相似文献
20.
Patricia Trotel-Aziz Michel Couderchet Guy Vernet Aziz Aziz 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):405-413
Chitosan (β-1,4-linked glucosamine oligomer) derived from crab shells conferred a high protection of grapevine leaves against
grey mould caused by Botrytis cinerea. Under controlled conditions, it was shown to be an efficient elicitor of some defense reactions in grapevine leaves and
to inhibit directly the in vitro development of B. cinerea. Treatment of grapevine leaves by chitosan led to marked induction of lipoxygenase (LOX), phenylalanine ammonia-lyase (PAL)
and chitinase activities, three markers of plant defense responses. Dose-response curves show that maximum defense reactions
(PAL and chitinase activities) and strong reduction of B. cinerea infection were achieved with 75–150 mg l−1 chitosan. However, greater concentrations of chitosan did not protect grapevine leaves with the same efficiency, but inhibited
mycelial growth in vitro. Present results underlined the potency of chitosan in inducing some defense responses in grapevine leaves which in turn
might improve resistance to grey mould. 相似文献