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1.
The aim of this study was to determine the changes in the mRNA expression of Toll-like receptors (TLRs) in hen ovarian follicles during follicular growth and in response to lipopolysaccharide (LPS). White follicles and the fifth largest to largest follicles (WF and F(5)-F(1), respectively) were collected from laying hens. To examine the effects of LPS, the laying hens were treated intravenously with LPS (1 mg/kg BW) 0, 3, 6, 12 and 24 h before examination. Expressions of TLRs and IL-1beta in the theca and granulosa layers were examined by semi-quantitative RT-PCR. Immunocytochemistry was performed to identify immunoreactive TLR-4. The theca layer expressed TLR-2, TLR-4, TLR-5 and TLR-7, whereas the granulosa layer expressed only TLR-4 and TLR-5. The expression of TLR-4 and TLR-5 in the theca layer increased significantly during follicular growth. In the granulosa layer, the expression of TLR-5 increased, but that of TLR-4 was unchanged. Expression of TLR-4 increased significantly during the period of 6 to 12 h of LPS treatment in the theca layer and during the period of 12 to 24 h in the granulosa layer of F(3). Immunoreaction products for TLR-4 were observed in theca interna and granulosa layers of WF and F(5)-F(1), with the greater amount observed in the theca interna. LPS treatment significantly increased expression of IL-1beta in the theca layer after 3 h and in the granulosa layer during the period of 12 to 24 h. These results suggest that TLRs are expressed in ovarian follicles and that TLR-4 and TLR-5 expression increase with the growth of follicles. Enhanced expression of TLR-4 and IL-1beta by LPS in the theca and granulosa layers suggests possible roles of TLR in recognition of microorganisms.  相似文献   
2.
Mango and papaya, which are rich sources of beta-carotene, are widely consumed in India. In this study, beta-carotene content and its bioaccessibility were determined in six locally available varieties of mango, namely, Badami, Raspuri, Mallika, Malgoa, Totapuri, and Neelam, and two varieties of papaya, namely, Honey Dew and Surya. Varietal differences were evident in both beta-carotene content and its bioaccessibility in the case of mango. beta-Carotene content in ripe mango ranged from 0.55 +/- 0.03 mg/100 g in the Malgoa variety to 3.21 +/- 0.25 mg/100 g in the Badami variety. Similarly, in the Honey Dew and Surya varieties of papaya, beta-carotene contents were 0.70 +/- 0.10 and 0.74 +/- 0.12 mg/100 g, respectively. Bioaccessibility of beta-carotene ranged from 24.5% in Badami to 39.1% in Raspuri varieties of mango. Considering both the percent bioaccessibility and the inherent beta-carotene content, the amount of bioaccessible beta-carotene was highest in the Mallika variety (0.89 mg/100 g), followed by Badami (0.79 mg/100 g). Because mango and papaya are also consumed as a blend with milk, the influence of the presence of milk on the bioaccessibility of beta-carotene from these fruits was also examined. Addition of milk generally brought about a significant increase in the bioaccessibility of beta-carotene from mango, the increase ranging from 12 to 56%. Bioaccessibility of beta-carotene from the two varieties of papaya examined was similar (31.4-34.3%). Addition of milk increased this bioaccessibility by 19 and 38% in these two varieties. Considering the beta-carotene content of mango and papaya, the latter has to be consumed in amounts roughly 3 times that of mango to derive the same amount of beta-carotene. Thus, this study has indicated that varietal differences exist in the content and bioaccessibility of beta-carotene in mango and that the addition of milk is advantageous in deriving this provitamin A from the fruit pulp of mango and papaya.  相似文献   
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4.
The effects of different solvent systems (methanol, ethanol, acetone, and their 50% aqueous concentrations) and extraction procedures (microwave, ultrasound, Soxhlet and maceration) on the antioxidant activity of aerial parts of Potentilla atrosanguinea were investigated by three different bioassays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays and ferric reducing antioxidant potential (FRAP). The 50% aqueous ethanol extracts exhibited strong antioxidant activity measured in terms of Trolox equivalent antioxidant capacity (TEAC) [(54.34 to 122.96, 29.82 to 101.22 and 13.64 to 41.43) mg of Trolox/g] with ABTS (*+), DPPH (*) and FRAP assays, respectively. In general, TEAC of Soxhlet extracts was found to be 1.8 and 3 times higher than ultrasound and maceration but slightly (1.2 times) higher than microwave. A positive correlation (r(2) = 0.931 to 0.982) was observed between total polyphenol (TPC) and total flavonoid (TFC) contents which ranged between 26.7 to 30.7 mg/g gallic acid equivalent and 16.8 to 20.8 mg/g quercetin equivalent respectively, with antioxidant activity. In addition, some of its bioactive phenolic constituents which contribute largely toward antioxidant potential such as chlorogenic acid, catechin, caffeic acid, p-coumaric acid and quercetin were also quantified in different extracts by RP-HPLC.  相似文献   
5.
A series of hot brand monoazo reactive dyes (9a-l) were obtained by the coupling of diazotized 1Hbenzo[ g]pyrazolo[3,4-b]quinoline-3-ylamine (5) with various cyanurated coupling components (8a-l) in good yield. Synthesized dyes were characterized by various spectroscopic techniques. Their dyeing performances as reactive dyes have been assessed on silk, wool, and cotton fabrics. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data of synthesized dyes have also been studied in detail.  相似文献   
6.
Gallinacins (Gal) are antimicrobial peptides that play significant roles in innate immunity in chickens. The aim of this study was to examine whether age of birds and egg-laying activity (laying and non-laying caused by feed-regulation) affect the mRNA expression of Gal-1, -2, and -3 in the vagina of hens, and whether their expressions are changed in response to the stimulation with Salmonella enteritidis (SE) and lipopolysaccharide (LPS). White Leghorn hens were divided into groups of young and old laying hens, and groups of laying and non-laying hens after feed-regulation. Vaginal cells were cultured and stimulated with SE or LPS. Expressions of Gal-1, -2, and -3 mRNA in their vaginal mucosa and cultured cells were examined by quantitative real-time RT-PCR. The expressions of Gal-1, -2, and -3 of the vaginal mucosa were significantly greater in old birds than in young birds. Expression of these Gals in the vagina were decreased in the regressed oviduct of non-laying birds compared with laying birds. The expressions of Gal-1, -2, and -3 in the cultured vaginal cells were increased by stimulation with SE or LPS within 24 h. These results suggest that the mRNA expressions of Gal-1, -2 and -3 in the vagina of laying hens increased with age, whereas they decreased in the regressed oviduct during the non-laying phase. Also, synthesis of these antimicrobial peptides in the vagina may increase in response to SE and LPS to eliminate SE bacteria.  相似文献   
7.
The present communication is a continuation of our earlier study on the natural serum haemagglutinin/lectins of Cirrhina mrigala, Clarias batrachus and Heteropneustes fossilis. Sera of Cirrhina mrigala, belonging to the major carp family, could not only agglutinate heterologous rabbit erythrocytes, but also lyse them spontaneously. This lysis of rabbit RBC by Cirrhina mrigala sera was calcium ion dependent and heat sensitive, indicating thereby that the haemolysis was mediated by the fish serum complement system via the classical pathway. Quantification of CH50 and APCH50 levels in the sera of Clarias batrachus and Heteropneustes fossilis as well as in the sera of amphibia, aves and mammals showed that lower vertebrates predominantly possessed an alternative pathway of the complement system, while on the other hand, in the higher vertebrates the major pathway of complement activation was classical. Furthermore sera of Clarias batrachus and Heteropneustes fossilis had opsonins, which could stimulate heterologous rat peritoneal macrophages to engulf Staphylococcus aureus with the production of superoxide anion. From this study we concluded that fishes have been armed with various powerful natural humoral defense systems for their protection against environmental pathogens.  相似文献   
8.
The intake rate of the local Vertisol is very low (0.08 cm/h). Vertical mulch was used from 1971 to 1976 in order to improve infiltration. Higher moisture contents were recorded near the mulch. The favourable effects of mulch extended to 1.5 m on either side of the mulch row. Vertical mulching exerted a greater influence on crop yields under dry conditions than in normal and above normal seasons. Compared with low yields in control plots (grain: 0.2 q/ha (20 kg/ha); straw: 9.5 q/ha (950 kg/ha)) mulches spaced at 2, 4 and 8 m produced 3.9 q/ha of grain and 19.0 q/ha of straw under the extremely dry conditions of 1972–1973. However, the increase in grain and straw yields under wet conditions in 1973–1974 was only 47.2 and 15.0%, respectively. Averaged over dry and wet years, vertical mulching resulted in 45.1 and 37.9% higher grain and straw yields. The favourable effects of vertical mulching were found to last for 4 years. Considering dry and wet years, a spacing of 4 m was found to be ideal. Placing sorghum stubble as a vertical mulch to the top of the salt zone (30 cm) was found to be as good as placing it to a depth of 90 cm.  相似文献   
9.
Three different modified dry‐grind corn processes, quick germ (QG), quick germ and quick fiber (QGQF), and enzymatic milling (E‐Mill) were compared with the conventional dry‐grind corn process for fermentation characteristics and distillers dried grains with solubles (DDGS) composition. Significant effects were observed on fermentation characteristics and DDGS composition with these modified dry‐grind processes. The QG, QGQF, and E‐Mill processes increased ethanol concentration by 8–27% relative to the conventional dry‐grind process. These process modifications reduced the fiber content of DDGS from 11 to 2% and increased the protein content of DDGS from 28 to 58%.  相似文献   
10.
Genetic Resources and Crop Evolution - Development of high yielding cultivars with determinate growth habit in photoperiod insensitive (PIS) background is one of the major objectives of breeding...  相似文献   
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