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41.
A chemical and biological validation of the traditional use of Hyoscyamus niger seeds as anti-inflammatory drug has been established. The methanolic extract of seeds of H. niger (MHN) was evaluated for its analgesic, anti-inflammatory and antipyretic activities in experimental animal models at different doses. MHN produced significant increase in hot plate reaction time, while decreasing writhing response in a dose-dependent manner indicating its analgesic activity. It was also effective in both acute and chronic inflammation evaluated through carrageenin-induced paw oedema and cotton pellet granuloma methods. In addition to its analgesic and anti-inflammatory activity, it also exhibited antipyretic activity in yeast-induced pyrexia model. Furthermore, the bioactive MHN under chemical investigation showed the presence of coumarinolignans as major chemical constituent and yielded a new coumarinolignan, cleomiscosin A methyl ether (1) along with four known coumarinolignans, cleomiscosin A (2), cleomiscosin B (3), cleomiscosin A-9′-acetate (4) and cleomiscosin B-9′-acetate (5). The structure elucidation of 1 was done by spectroscopic data interpretation and comparative HPLC analysis. Cleomiscosin A, but not its isomer cleomiscosin B, reduced dry and wet weight of cotton pellet granuloma in mice. This suggests that cleomiscosin A is an important constituent of MHN responsible for anti-inflammatory activity.  相似文献   
42.
Laccases play important roles in the development of fruiting bodies and in lignin degradation by basidiomycetes. In this study, we present novel phenotypes of transgenic tobacco plants with a chimeric gene for fungal laccase under the control of the cauliflower mosaic virus 35S promoter. At the flowering stage, the transgenic plants that produced recombinant laccase had brownish anthers instead of the greenish anthers of wild-type plants. The brownish anthers exhibited male sterility with a nondehiscent phenotype at varying frequencies. The frequency of nondehiscence depended on the temperature at which plants were cultivated and it was higher at 24°C than at 29°C. The cell wall structures of transgenic anther tissues were almost the same as in the wild type, but the stomium was severely deformed, and abnormal components were apparent in cells of the endothecium and epidermis. Furthermore, the pattern of deposition of flavonoids in the transgenic anther epidermis differed from the wild-type pattern. The expression of laccase also induced other phenotypic changes in the flowers of transgenic plants, namely, increased petal number, fused and petaloid stamens, and doubling of floral organs. These results indicate that the ectopic expression of laccase influences various aspects of flower development.  相似文献   
43.
Experimental trials were conducted at Integrated Pest Management Programme, National Agriculture Research Centre Islamabad, to evaluate the resistance of host plants (cereals) against Rhopalosiphum padi (L.). For evaluation of susceptibility, twenty varieties/-advanced lines of National Uniform Wheat Yield Trails (NUWYT) Normal (N) of year 2004-2005 were used. In seedling bulk tests varieties/advanced lines were grouped into three categories resistant, moderately resistant and susceptible. Data from seedling bulk tests showed that DN-47 and PR 87 lines of wheat were resistant to aphid as compared to the other varieties/-advanced lines. In antixenosis tests varieties/-advanced lines were grouped into three categories, least preferred, moderately preferred, highly preferred. Lines V-01180, DN-47 and PR-84 were least preferred, sixteen varieties/-advanced lines were moderately preferred and only one variety V-9021 was found to be highly preferred.  相似文献   
44.

A feeding trial of 10 weeks duration was undertaken on laying hens (n = 240) to evaluate feeding value of rice distiller’s dried grains with soluble (rDDGS) with or without enzyme supplementation (α-amylase, β-glucanase, xylanase, carboxymethylcellulase, pectinase, proteinase, α-galactosidase, β-galactosidase, lipase, and phytase), following 4 × 2 factorial design, on egg production, nutrient utilization, and cost economics of egg production. The birds were randomly assigned to eight dietary treatments with 30 birds/treatment. The birds were housed individually in layer cages and each bird was taken as an experimental unit. Eight experimental diets were prepared by incorporating four levels (0, 50, 75, and 100 g/kg) of rDDGS with and without enzyme supplementation. The results revealed a significant (P < 0.01) increase of egg mass, feed intake, egg production, and body weight gain in dietary treatments with up to 75 g rDDGS though the values were statistically similar to the hens fed 100 g rDDGS. Enzyme supplementation resulted in significant (P < 0.01) improvement of egg mass, egg production, feed conversion ratio (FCR) per dozen eggs, FCR per kilogramme egg mass, and net FCR. The significantly (P < 0.01) higher yolk index was observed at 100 g rDDGS level, while shell thickness improved significantly (P < 0.01) up to 75 g rDDGS level. No significant effect of rDDGS inclusion was observed on shape index, albumin index, and Haugh unit. Enzyme supplementation significantly improved the shell thickness and yolk colour of eggs. Nitrogen, calcium, and phosphorus retention and dry matter metabolizability did not show any significant treatment effects. There was significant (P < 0.01) reduction in feed-cost per kilogramme egg mass or per dozen eggs with the increased DDGS levels and dietary enzyme supplementation. It was concluded that rDDGS can be used up to 100 g/kg diet of laying hens along with enzyme supplementation for better productivity of layer hens.

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45.
Owing to increased tolerance and the development of resistance in stored product insects to the fumigant phosphine, in recent years there has been a shift in the target terminal concentration from 100 ppm (100 mL m(-3)) to a higher level of 1000 ppm to achieve 100% insect mortality in 7 day commodity treatments. Therefore, there is a need to investigate whether the revised target concentration could be achieved for food commodities fumigated with phosphine at the standard dose of 2 g m(-3) for 7 days under airtight conditions at > or = 25 degrees C. When different types of food commodity (total 74) were fumigated (300 g per replicate) with phosphine at 2 g m(-3) for 7 days, the terminal gas concentrations in the free space of the commodities varied from 0 to > 2000 ppm. In chambers containing no substrate, a 1417 ppm concentration was recorded. Paddy rice, most of the oilseeds, shelled tree nuts, butter beans, cardamom, green gram splits, coriander powder, rice bran and cocoa powder were more sorptive (> or =60%), such that the target concentration of 1000 ppm was not achieved at the end of 7 days. For these commodities, increased doses of 3-6 g m(-3) were required to attain 1000 ppm. In-shell almonds, green cardamom, in-shell peanuts, leaf tea, tamarind pulp and sunflower seeds were exceptionally sorptive (>90%), so that 0, 41, 112, 168, 203 and 217 ppm respectively were noted at the end of 7 days; the dose must exceed 6 g m(-3) for effective fumigation of these commodities.  相似文献   
46.
Activation-induced cytidine deaminase (AID) is required for the DNA cleavage step in immunoglobulin class switch recombination (CSR). AID is proposed to deaminate cytosine to generate uracil (U) in either mRNA or DNA. In the second instance, DNA cleavage depends on uracil DNA glycosylase (UNG) for removal of U. Using phosphorylated histone gamma-H2AX focus formation as a marker of DNA cleavage, we found that the UNG inhibitor Ugi did not inhibit DNA cleavage in immunoglobulin heavy chain (IgH) locus during CSR, even though Ugi blocked UNG binding to DNA and strongly inhibited CSR. Strikingly, UNG mutants that had lost the capability of removing U rescued CSR in UNG-/- B cells. These results indicate that UNG is involved in the repair step of CSR yet by an unknown mechanism. The dispensability of U removal in the DNA cleavage step of CSR requires a reconsideration of the model of DNA deamination by AID.  相似文献   
47.
Sandy cropland soils in NW Europe were found to contain unusually high organic‐carbon (OC) levels, and a link with their land‐use history has been suggested. This study's aim was to assess the discriminating power of physical and chemical fractionation procedures to yield information on soil‐organic‐matter (OM) stability for these soils. In relict‐ and cultivated‐heathland soils, much higher proportions of 6% NaOCl treatment–resistant but 10% HF–soluble OC (MOC) and N (32.2% and 29.9%) were measured compared to a set of “permanent"‐cropland soils without a history of heathland land use (11.9% and 8.5%). Also, the proportions of 6% NaOCl– and 10% HF treatment–resistant OC and N in the relict and cultivated heathlands (19.2% and 12.0%) were higher than in the permanent‐cropland soils (17.7% and 5.7%). Stepwise multiple linear‐regression yielded a significant relationship between the annual mineralization (g C [100 g OC]–1), soil OC (g C kg–1) content, and %MOC: Annual mineralization = 4.347 – 0.087 soil OC – 0.032 %MOC (R2 = 0.65). Combinations of incubation experiments for quantification of the labile soil OM pool with chemical fractionation may thus yield meaningful data for development of soil‐organic‐matter models with measurable pools, but their applicability will be limited to specific combinations of former land use with soil, climate, and current management.  相似文献   
48.
Abstract: Dimethoate accumulation in liver and muscle tissues of a fresh-water fish, Clarias bactrachus L., was measured by gas liquid chromatography. Fish were exposed to a sub-lethal concentration of the pesticide in the laboratory water tank for a period of eight days. The accumulation increased up to two days, followed by decrease on the 4th and 8th days of exposure in both liver and muscle tissues. Maximum accumulation was found in liver. After eight days of exposure, fish were released into pesticide-free water to study the rate of loss of the pesticide. It was found that liver and muscle tissues were cleared of dimethoate after four and eight days respectively.  相似文献   
49.
50.
Genetic diversity and comprehensive performance are the basis for the discovery and efficient use of proso millet(Panicum miliaceum L.) core collections. In this study, 386 proso millet core collections were used as materials to observe inflorescence color, leaf phase, inflorescence density, axis shape, branched spike length, panicle type, trichome, measured area of the top3 leaves, and chlorophyll content of the top3 leaves at filling stage. These core collections were also used to record growth period, plant height, diameter of main stem, plant tiller number, branch number, panicle length, panicle number per plant, and panicle weight per plant at the maturation stage. Starch, fat, protein, and yellow pigment contents in the grain and 1 000-seed weight were also measured after harvest. Then, quantitative traits were used for diversity analysis and comprehensive evaluation of each collection. Correlations between all traits were also analyzed. Results showed that among the 8 quality traits, the Shannon index(H′) of hull color was the highest(1.588) followed by the H′ of inflorescence density(0.984). However, inflorescence color and axis shape were lower. The H′ of 16 quantitative traits were significantly higher than the quality traits with the following traits having the highest indices: fat content(2.092), 1 000-seed weight(2.073), top3 leaves area(2.070), main stem diameter(2.056), and plant height(2.052). Furthermore, all other traits had a diversity higher than 1.900. After a comprehensive evaluation of phenotypic traits, plant height, diameter of main stem, plant tiller number, leaf area of top3 leaves, and 1 000-seed weight were the biggest contributors to the principal components. Six high-fat and high-protein cultivars, including Nuoshu, A75-2, Zhiduoaosizhi, Panlonghuangmi, Xiaobaishu, and Xiaohongshu were also screened. Correlations between the quantitative traits were significant, including the correlation between quality traits and quantitative traits. In conclusion, the core collections can be used as basis for discriminating among proso millet cultivars based on related traits and for further studies on millet with rich genetic diversity, good representation, and significant collection between traits.  相似文献   
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