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951.
Five novel permanent cell lines have been established from gill, heart, kidney, eye and fin of snubnose pompano, Trachinotus blochii. They were designated as snubnose pompano gill (SPG), snubnose pompano heart (SPH), snubnose pompano kidney (SPK), snubnose pompano eye (SPE) and snubnose pompano fin (SPF), respectively. All these cell lines were characterized and cryopreserved successfully at different passage levels. Cell lines were passaged every alternate day; SPG, SPH, SPK, SPE and SPF cell lines attained passage levels of 68, 74, 82, 79 and 106, respectively, since the initiation of their development in 2019. The cell lines grew well in Leibovitz's 15 medium containing 15% foetal bovine serum at 28°C. Immunophenotyping of the cell lines revealed the presence of fibronectin and pancytokeratin. No mycoplasma contamination was found. The transfection study revealed the gene expression efficiency of these cell lines by expressing the green fluorescent protein (GFP). The authentication on origin of cell lines from T. blochii was confirmed by amplification of species-specific mitochondrial cytochrome oxidase I gene. The results showed the susceptibility of these cell lines to fish nodavirus (FNV) and tilapia lake virus (TiLV) and resistance to cyprinid herpesvirus 2 (CyHV-2). The FNV infection in the cell lines was confirmed by RT-PCR, Western blot, ELISA and immunocytochemistry, while TiLV infection was confirmed by RT-PCR assay. These results revealed that these cell lines are suitable for virological and foreign gene expression studies.  相似文献   
952.
  • 1. Habitat loss and habitat fragmentation are usually correlated while habitat degradation may occur independently of them. Natural and anthropogenic disturbances increase the spatial fragmentation of seagrass meadows with unknown consequences on the vegetative development achieved by seagrass.
  • 2. Cover and spatial fragmentation of Thalassia testudinum meadows in three coral reef lagoons of the Veracruz Reef System,VRS (SW Gulf of México) were quantified by analysing low‐altitude images acquired by photographic and digital video cameras from a helium‐filled blimp. Spatial fragmentation was quantified as the ratio of the length of meadow edge to meadow area. The number of blowouts (erosive gaps in seagrass meadows) was also recorded.
  • 3. Meadow cover was negatively correlated with the length of meadow edge to meadow area ratio. The number of blowouts per ha of T. testudinum meadow was negatively correlated with meadow cover and positively with the length of meadow edge to meadow area ratio. Wave exposure is probably a main component of the processes determining the cover and spatial fragmentation of T. testudinum meadows in VRS.
  • 4. Low cover and high spatial fragmentation of T. testudinum meadows in VRS are associated with low vegetative development of this seagrass species. Copyright © 2011 John Wiley & Sons, Ltd.
  相似文献   
953.
Many plants are used in Ayurveda for the treatment of tuberculosis. Our aim was to examine if these plants possess any specific molecule that inhibits Mycobacterium tuberculosis. One of them, Kaempferia galanga, yielded an anti-TB molecule, ethyl p-methoxycinnamate (EPMC). By resazurin microtitre assay (REMA), EPMC was shown to inhibit M. tuberculosis H37Ra, H37Rv, drug susceptible and multidrug resistant (MDR) clinical isolates (MIC 0.242-0.485 mM). No cross resistance was observed to any standard anti-TB drugs in the MDR strains. The compound did not inhibit any prototype bacteria tested. EPMC seems to be a potential anti-TB lead molecule.  相似文献   
954.
Phytochemical investigation of Caralluma adscendens var. gracilis and Caralluma pauciflora (Asclepiadaceae) whole plant extracts allowed to isolate one pregnane glycoside and two pregnanes characterized as 12β,20-O-dibenzoyl-5α,6-dihydrosarcostin β-oleandropyranosyl-(1→4)-β-cymaropyranosyl-(1→4)-β-digitoxypyranosyl-(1→4)-β-cymaropyranosyl-(1→4)-β-cymaropyranoside (1), 12β-O-benzoyl-3β,11α,14β,20R-pentahydroxy-pregn-5-ene (2), and 11α-O-benzoyl-3β,12β,14β,20R-pentahydroxy-pregn-5-ene (3), respectively. Their structural characterization was obtained on the basis of extensive NMR spectral studies. Three known pregnane glycosides along with lupeol and β-sitosterol were also isolated and characterized.  相似文献   
955.
Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 μM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 μM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 μg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA.  相似文献   
956.
In some areas of the Mediterranean basin where the understory stratum represents a critical fire hazard, managing the canopy cover to control the understory shrubby vegetation is an ecological alternative to the current mechanical management techniques. In this study, we determine the relationship between the overstory basal area and the cover of the understory shrubby vegetation for different dominant canopy species (Pinaceae and Fagaceae species) along a wide altitudinal gradient in the province of Catalonia (Spain). Analyses were conducted using data from the Spanish National Forest Inventory. At the regional scale, when all stands are analysed together, a strong negative relationship between mean shrub cover and site elevation was found. Among the Pinaceae species, we found fairly good relationships between stand basal area and the maximum development of the shrub stratum for species located at intermediate elevations (Pinus nigra, Pinus sylvestris). However, at the extremes of the elevation-climatic gradient (Pinus halepensis and Pinus uncinata stands), stand basal area explained very little of the shrub cover variation probably because microsite and topographic factors override its effect. Among the Fagaceae species, a negative relationship between basal area and the maximum development of the shrub stratum was found in Quercus humilis and Fagus sylvatica dominated stands but not in Quercus ilex. This can be due to the particular canopy structure and management history of Q. ilex stands. In conclusion, our study revealed a marked effect of the tree layer composition and the environment on the relationship between the development of the understory and overstory tree structure. More fine-grained studies are needed to provide forest managers with more detailed information about the relationship between these two forest strata.  相似文献   
957.
Wood specific gravity of some tree species in the Garhwal Himalayas,India   总被引:2,自引:2,他引:0  
Estimation of terrestrial biomass depends critically on reliable information about wood specific gravity of forest trees. In recent years, wood specific gravity has become more important when exploring the universality of functional traits of plants and estimating their global carbon stocks. To estimate their specific gravity, wood samples were collected from a total of 34 tree species, 30 from lower elevations and 4 from upper elevations in the Garhwal Himalayas, India. The results show that the average wood specific gravity was 0.631 (ranging between 0.275 ± 0.01 and 0.845 ± 0.03) for the species at lower elevations and 0.727 (ranging between 0.628 ± 0.02 and 0.865 ± 0.02) for the upper elevations. The average wood specific gravity for the upper elevation species was 9.6% greater than that for the species at lower elevations. Aegle marmelos among the lower elevation species and Quercus leucotrichophora among the upper elevation species had the highest wood specific gravity, which were 0.845 ± 0.03 and 0.865 ± 0.02, respectively.  相似文献   
958.
959.
960.
The present study was carried out to investigate the sub-lethal toxicity of technical grade deltamethrin (a synthetic pyrethroid) of concentration 1.61 μg/L (1/3rd of 96 h LC50) on hematological and biochemical parameters of catla (Catla catla) fingerlings and its amelioration through dietary vitamin C. The deltamethrin exposed fishes were fed with different levels of supplemented vitamin C such as 50, 250, 500 and 1000 mg/kg diet to see its ameliorating effect by assaying hematological parameters viz. total erythrocyte count (TEC), total leukocyte count (TLC), hemoglobin content (Hb), total serum protein, albumin, globulin, albumin–globulin ratio and biochemical parameters such as lactate dehydrogenase (LDH), acetylcholine esterase (AChE), alanine amino transferase (ALT), aspartate amino transferase (AST), total adenosine triphosphatase (ATPase), magnesium adenosine triphosphatase (Mg2+-ATPase) and sodium potassium adenosine triphosphatase (Na+, K+-ATPase) activities. The finding of this study showed that deltamethrin had negative effect on the hematological and biochemical parameters of Catla catla. The experimental group, which was exposed to deltamethrin and fed with normal diet showed significantly lower values (P ? 0.05) of all parameters studied except ALT activity. This might be due to possible disruption of hematopoiesis and proteosynthesis. However, the fish fed with varied concentration of vitamin C in diets neutralized the toxic effect of deltamethrin, as evidenced by significantly lowered hematological and biochemical response. Vitamin C @ 1000 mg/kg diet was the most effective in amelioration of harmful effect of deltamethrin on hematological and biochemical parameters of catla fingerlings. The result suggests that vitamin C can be effectively used to neutralize the toxic effect of deltamethrin on catla.  相似文献   
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