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51.
Present study aimed to determine the optimum dietary lipid level in snakehead murrel channa striatus broodstocks. Triplicate groups of fish were fed for 240 days with isonitrogenous experimental diets with increasing lipid levels (100, 140, and 180 g kg?1), using fish oil and soybean oil as the lipid sources with the ratio of (1:1). Weight gain, GSI, fecundity, oocyte diameter and number of mature oocyte were found to be significantly higher in the group fed with diet containing 180 g kg?1 lipid level. Muscle fatty acid profile showed a significant increase in LA (18:2n‐6), LNA (18:3n3), total PUFA, n‐6 and ArA (20:4n‐6) in fish fed with diet containing 180 g kg?1 lipid. Increasing lipid level up to 180 g kg?1 resulted in significant increase in PUFA (LA & LNA), lc‐PUFA (EPA, DHA, ArA), total PUFA, n‐3 and n‐6 series in ovary and liver of female C. striatus.  相似文献   
52.
Spatial/temporal controls of development are regulated by the homeotic (HOX) gene complex and require integration with oncogenes and tumour suppressors regulating cell cycle exit. Spontaneously derived neoplastic canine mammary carcinoma cell models were investigated to determine if HOX expression profiles were associated with neoplasia as HOX genes promote neoplastic potential in human cancers. Comparative assessment of human and canine breast cancer expression profiles revealed remarkable similarity for all four paralogous HOX gene clusters and several unlinked HOX genes. Five canine HOX genes were overexpressed with expression profiles consistent with oncogene‐like character (HOXA1, HOXA13, HOXD4, HOXD9 and SIX1) and three HOX genes with underexpressed profiles (HOXA11, HOXC8 and HOXC9) were also identified as was an apparent nonsense mutation in HOXC6. This data, as well as a comparative analysis of similar data from human breast cancers suggested expression of selected HOX genes in canine mammary carcinoma could be contributing to the neoplastic phenotype.  相似文献   
53.
In recent years, there has been considerable interest in lectins from marine invertebrates. In this study, the biological activities of a lectin protein isolated from the eggs of Sea hare (Aplysia kurodai) were evaluated. The 40 kDa Aplysia kurodai egg lectin (or AKL-40) binds to D-galacturonic acid and D-galactose sugars similar to previously purified isotypes with various molecular weights (32/30 and 16 kDa). The N-terminal sequence of AKL-40 was similar to other sea hare egg lectins. The lectin was shown to be moderately toxic to brine shrimp nauplii, with an LC50 value of 63.63 µg/mL. It agglutinated Ehrlich ascites carcinoma cells and reduced their growth, up to 58.3% in vivo when injected into Swiss albino mice at a rate of 2 mg/kg/day. The morphology of these cells apparently changed due to AKL-40, while the expression of apoptosis-related genes (p53, Bax, and Bcl-XL) suggested a possible apoptotic pathway of cell death. AKL-40 also inhibited the growth of human erythroleukemia cells, probably via activating the MAPK/ERK pathway, but did not affect human B-lymphoma cells (Raji) or rat basophilic leukemia cells (RBL-1). In vitro, lectin suppressed the growth of Ehrlich ascites carcinoma and U937 cells by 37.9% and 31.8%, respectively. Along with strong antifungal activity against Talaromyces verruculosus, AKL showed antibacterial activity against Staphylococcus aureus, Shigella sonnei, and Bacillus cereus whereas the growth of Escherichia coli was not affected by the lectin. This study explores the antiproliferative and antimicrobial potentials of AKL as well as its involvement in embryo defense of sea hare.  相似文献   
54.
Alzheimer’s disease (AD) is a devastating neurodegenerative disease and the most common cause of dementia. It has been confirmed that the pathological processes that intervene in AD development are linked with oxidative damage to neurons, neuroinflammation, tau phosphorylation, amyloid beta (Aβ) aggregation, glutamate excitotoxicity, and cholinergic deficit. Still, there is no available therapy that can cure AD. Available therapies only manage some of the AD symptoms at the early stages of AD. Various studies have revealed that bioactive compounds derived from marine organisms and plants can exert neuroprotective activities with fewer adverse events, as compared with synthetic drugs. Furthermore, marine organisms have been identified as a source of novel compounds with therapeutic potential. Thus, there is a growing interest regarding bioactive compounds derived from marine sources that have anti-AD potentials. Various marine drugs including bryostatin-1, homotaurine, anabaseine and its derivative, rifampicins, anhydroexfoliamycin, undecylprodigioisin, gracilins, 13-desmethyl spirolide-C, and dictyostatin displayed excellent bioavailability and efficacy against AD. Most of these marine drugs were found to be well-tolerated in AD patients, along with no significant drug-associated adverse events. In this review, we focus on the drugs derived from marine life that can be useful in AD treatment and also summarize the therapeutic agents that are currently used to treat AD.  相似文献   
55.
As a free water resource, groundwater is extensively used for agricultural purposes. This is sometimes referred to as underground irrigation. Two-year lysimetric experiments from 2009 to 2011 were conducted in order to determine the effects of different shallow water table levels without any supplementary irrigation on water requirements, yield production and water-use efficiencies of three wheat cultivars namely W33g, Cross Alborz and Bahar. The experiments were carried out in a randomized complete block factorial experiment design with three replicates at the Razi University Lysimetric Research Station, Iran. Nine treatments were applied to each experiment by maintaining groundwater EC of 5 dS m?1, with different water table levels of 0.6, 0.80 and 1.10 m, respectively. The results showed the highest and lowest groundwater uses by wheat for water table depths of 0.6 m and 1.10 m, during the experimental years, respectively. For all wheat cultivars, the average groundwater contributions were found to be 70.90% (5 mm day?1), 67.85% (4.3 mm day?1) and 63.4% (3.6 mm day?1) for water table levels of 0.60, 0.80 and 1.10 m, respectively. Finally, the results showed the highest yield production and groundwater-use efficiency under water table levels of 0.80 m for all the three wheat cultivars.  相似文献   
56.
In this study, the effect of spirulina meal (Spirulina platensis) as a feed additive on growth and physiological response of Oscar fish,Astronotus ocellatus, was assessed using four diets including control without spirulina supplementation, 13.75 g/kg spirulina (SP1), 27.50 g/kg spirulina (SP2) and 55 g/kg spirulina (SP3). One hundred and twenty fish (10.41 ± 0.25 g) were disturbed to twelve aquariums and fed to apparent satiation three times a day for 8 weeks. The result showed that the SP3 treatment had statistically better growth performance, feeding parameters, total protease activity, total protein and lipid contents than the control. Moreover, haemoglobin, haematocrit, mean erythrocyte haemoglobin and mean erythrocyte haemoglobin concentrations were improved considerably in the SP3 treatment compared with the control. The SP3 treatment showed higher total protein and albumin levels, but lower triglycerides, cholesterol levels and liver enzyme activities than the control. Also, serum complements (C3, C4), lysozyme activity and total carotenoid contents in fish skin significantly increased in the SP3 treatment compared with the control. The results of this study suggest that spirulina powder at the level of 55 g/kg of the diet can be used as a functional natural feed additive to improve the performance of Oscar fish.  相似文献   
57.
Participatory forest management is credited for supporting social learning processes and fostering capacity of forest users for collaboration and collective actions. Despite more than a decade of practice, the empirical evidence substantiating the contribution of participatory management for the capacity development of forest users is scarce. This study assesses a participatory forest management program in Madhupur Sal forest, Bangladesh, by comparing the capacity of de-facto groups of participants and nonparticipants and identifies factors that influence the capacity development. Data were collected using a mixed method approach which combines both qualitative and quantitative methods of data collection. Results indicate that participants differed from nonparticipants significantly in terms of various capacity dimensions related to collective actions. Extension services, credit support, trust within society, information and communication influence the level of capacities in tribal population to adapt and respond to changes. The initiatives to manage natural resources are likely to be more successful if the forest management program initiators consider several factors that influence the capacity development of resource users.  相似文献   
58.
The aim of the present study was to investigate the effects of different salinities (0‰, 6‰ and 12‰) and temperatures (23, 27 and 31 °C) on the food consumption, growth, blood biochemistry and haematocrit of Goldfish. After 45 days of exposure to different salinities and temperatures, Goldfish showed a good adaptation to these salinities and temperatures in terms of blood biochemistry (glucose and triglyceride) and haematocrit. Salinities (0‰ and 6‰) and temperatures (23 and 27 °C) did not affect the weight gain, specific growth rate, final biomass and feed conversion rates, but these parameters were significant (P<0.05) at 12‰ salinity and 31 °C temperature. Plasma total protein levels decreased with the increase in salinity (P<0.05), while they were independent of temperature. In conclusion, Carassius auratus, a freshwater stenohaline fish, showed good growth in saline waters with maximum 12‰ salinity and 31 °C temperature.  相似文献   
59.
Household and homegarden characteristics in southwestern Bangladesh   总被引:1,自引:0,他引:1  
Homegardens around the world often exhibit remarkable variation in composition and structure depending on the physiographic and climatic conditions of the area and a wide variety of household characteristics. This research investigated whether households’ contextual attributes have a quantitative and predictable relationship with homegarden vegetation structure from a total of 402 randomly selected households in southwestern Bangladesh. The central analytical tool to test the relationship between household characteristics and the homegarden vegetation structure was multiple regression. The moderate to low regression R 2 values revealed that most household characteristics were not strong predictors of homegarden vegetation structure. Despite the weak explanatory power of the majority household characteristics, time spent and homestead size had the strongest relationship with species richness and income in a homegarden. Households being the main source of labor for a majority of households suggest that outside labor shortage would not influence homegarden vegetation structure. We suggest that women’s active participation in homegardening activities to reduce gender inequality in the family which will perhaps result in more diverse and economically viable homegarden. However, increasing population density and the concomitant fragmentation of landholdings to homesteads may create opportunity for homegarden promotion in Bangladesh. Our results of decreased species richness in the homegarden with improved roads and proximity to market support the general hypothesis of subsistence homegardens and did not reinforce the general fears of gradual decline in species richness due to a market economy. Household characteristics had no influence on the presence of IUCN Red Listed species in the homegarden, except for gender and education of the household head. However, most homegardeners were unaware about the status of red listed species, suggesting that occurrence of red listed species in homegardens was by chance. Thus, efforts to improve awareness and to save and conserve rare species from extirpation are needed.  相似文献   
60.
The present study investigated the optimum dietary protein level for the maturation of adult Pangasianodon hypophthalmus broodstock. Four isocaloric diets containing 250, 300, 350 and 400 g kg?1 of protein levels were prepared and presented to triplicate groups of fish. The fish (mean weight 770 ± 17.23 g and 712 ± 23.42 g for females and males respectively) were stocked in outdoor canvas tanks (4 m × 1 m × 1 m) at a stocking density of 20 fish/tank with a male: female ratio of 1:4. The fish were fed the test diets to satiation twice daily for 6 months. Gonadosomatic index (GSI) and fecundity were similar among fish fed dietary protein levels, higher than those fed on the 250 g kg?1. Final weight, weight gain, oocyte weight were significantly highest (< 0.05) for the fish fed 350 and 400 g kg?1 dietary protein treatments. Only the 350 g kg?1 dietary protein treatment resulted in significantly best ovipositor diameter and % ripe egg. Amino acid levels were highest in the muscle followed by the oocyte and liver of fish fed 350 and 400 g kg?1 dietary protein levels. The present results suggested that a dietary protein level of 350 g kg?1 can be recommended for the development of P. hypophthalmus broodstock.  相似文献   
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