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161.
This study involves enzymatic extraction of fucoidan from Sargassum swartzii and further purification via ion-exchange chromatography. The chemical and molecular characteristics of isolated fucoidan is evaluated concerning its anti-inflammatory potential in RAW 264.7 macrophages under LPS induced conditions. Structural properties of fucoidan were assessed via FTIR and NMR spectroscopy. NO production stimulated by LPS was significantly declined by fucoidan. This was witnessed to be achieved via fucoidan acting on mediators such as iNOS and COX-2 including pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), with dose dependent down-regulation. Further, the effect is exhibited by the suppression of TLR mediated MyD88, IKK complex, ultimately hindering NF-κB and MAPK activation, proposing its therapeutic applications in inflammation related disorders. The research findings provide an insight in relation to the sustainable utilization of fucoidan from marine brown algae S. swartzii as a potent anti-inflammatory agent in the nutritional, pharmaceutical, and cosmeceutical sectors.  相似文献   
162.
通过马氏珠母贝与羊栖菜的混养实验,测定了贝释放的氮磷含量及羊栖菜对贝释放氮磷的吸收量,比较了实验组(有贝)、模拟组(无贝)与对照组之间羊栖菜的生长差异,并进一步阐述了羊栖菜对马氏珠母贝代谢产物的吸收速率与去除效率。结果表明:实验组中,马氏珠母贝释放的氮以及羊栖菜吸收的氮均以NH4+-N为主;对4种代谢产物NH;-N,NO3-N,NO2-N,PO4^3+-P,马氏珠母贝的释放比例为27:21:1:18,而羊栖菜的吸收比例为17:12:1:2.6。方差分析结果表明,实验组与模拟组相比,藻对氮磷的吸收速率具有明显的促进作用(P〈0.05);各组间生长情况的Duncan’s多重比较表明,各组羊栖菜13增质量与13增长值均存在显著性差异(P〈0.05),大小顺序为:实验组〉对照组C〉模拟组〉对照组A〉对照组B。这表明马氏珠母贝的代谢产物能够促进羊栖菜生长。  相似文献   
163.
采用MTT法测定不同浓度马尾藻多糖(Sargassum polysaccharide,SP)对正常猪脾淋巴细胞体外增殖及其感染猪繁殖与呼吸障碍综合征病毒(PRRSV)后培养活性的影响,并用Griess和ELISA法分别检测细胞培养上清液中一氧化氮(NO)、白细胞介素2(IL-2)和γ干扰素(IFN-γ)的水平。试验结果表明:25~400μg.mL-1的SP能协同伴刀豆球蛋白(ConA)显著促进T淋巴细胞体外增殖,400μg.mL-1的SP显著促进脂多糖(LPS)刺激的B淋巴细胞体外增殖活性。SP提高正常猪脾细胞体外培养不同时间段的NO分泌量,与对照组比较,差异显著(P<0.05);不同浓度SP提高PRRSV感染的猪脾细胞体外培养分泌NO量,与病毒对照组比较,培养8 h时200μg.mL-1SP、12 h时100~400μg.mL-1SP、24 h时100μg.mL-1和400μg.mL-1SP均能显著地促进NO分泌(P<0.05)。400μg.mL-1SP极显著促进体外培养的猪脾细胞分泌IL-2(P<0.01),100μg.mL-1和400μg.mL-1SP显著促进PRRSV感染猪脾细胞IL-2和IFN-γ的分泌。结论:马尾藻多糖通过促进猪脾细胞增殖和分泌NO、IL-2和IFN-γ来调节免疫细胞活性和抗病毒能力。  相似文献   
164.
  • 1. Invasive species threaten marine biodiversity on a global scale.
  • 2. To test whether marine reserves provide resistance to invading species, the abundance of two conspicuous invaders, a seaweed and an oyster, were measured inside marine reserves and in comparable areas outside reserves in north‐western Washington State.
  • 3. Densities of both invaders were significantly higher in marine reserves than in comparable unprotected areas outside reserves. Although the causal mechanisms have not yet been identified, differential rates of human harvest do not appear to be responsible for the patterns observed.
  • 4. It is provisionally suggested that physical or biological aspects of the reserves themselves may directly or indirectly facilitate biological invasion.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
165.
目的:研究马尾藻多糖纳米脂质体对鸡白痢的预防效果。方法:采用人工感染鸡白痢沙门氏菌病症模型,分别加马尾藻多糖纳米脂质体100、200、400 mg/kg于人工感染雏鸡,观察马尾藻多糖纳米脂质体对鸡白痢的预防作用。结果:马尾藻多糖纳米脂质体能降低鸡人工感染沙门氏菌的死亡率。结论:马尾藻多糖纳米脂质体对鸡白痢有一定的预防作用。  相似文献   
166.
Sargassum horneri (S. horneri) is a well-known brown seaweed widely distributed worldwide. Several biological activities of S. horneri have been reported. However, its effects on lipid metabolism and the underlying mechanisms remain elusive. In the present study, we examined the inhibitory effect of the active compound “(−)-loliolide ((6S,7aR)-6-hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydro-1-benzofuran-2(4H)-one (HTT))” from S. horneri extract on lipid accumulation in differentiated adipocytes. MTT assays demonstrated that (−)-loliolide is not toxic to 3T3-L1 adipocytes in a range of concentrations. (−)-loliolide significantly reduced intracellular lipid accumulation in the differentiated phase of 3T3-L1 adipocytes as shown by Oil Red O staining. Western blot analysis revealed that (−)-loliolide increased the expression of lipolytic protein phospho-hormone-sensitive lipase (p-HSL) and thermogenic protein peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1). Additionally, (−)-loliolide decreased expression of adipogenic and lipogenic proteins, including sterol regulatory element-binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), and fatty acid-binding protein 4 (FABP4) in 3T3-L1 adipocytes. These results indicate that (−)-loliolide from S. horneri could suppress lipid accumulation via regulation of antiadipogenic and prolipolytic mechanisms in 3T3-L1 cells. Considering the multifunctional effect of (−)-loliolide, it can be useful as a lipid-lowering agent in the management of patients who suffer from obesity.  相似文献   
167.
Sargassum brown seaweed is reported to exhibit several biological activities which promote human health, such as anticancer, antimicrobial, antidiabetic, anti-inflammatory, and antioxidant activity. This study aimed to investigate the anti-inflammatory and antioxidant activity of crude lipid extracts of Sargassum ilicifolium obtained from four different coastal areas in Indonesia, namely Awur Bay–Jepara (AB), Pari Island–Seribu Islands (PI), Sayang Heulang Beach–Garut (SHB), and Ujung Genteng Beach–Sukabumi (UGB). Results showed that treatment of RAW 264.7 macrophage cells with UGB and AB crude lipid extracts (12.5–50 µg/mL) significantly suppressed the nitric oxide production after lipopolysaccharide stimulation, both in pre-incubated and co-incubated cell culture model. The anti-inflammatory effect was most marked in the pre-incubated cell culture model. Both two crude lipid extracts showed 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and high ferric reducing antioxidant power, which were amounted to 36.93–37.87 µmol Trolox equivalent/g lipid extract and 681.58–969.81 µmol FeSO4/g lipid extract, respectively. From this study, we can conclude that crude lipid extract of tropical S. ilicifolium can be further developed as a source of anti-inflammatory and antioxidant agent.  相似文献   
168.
Total lipids from the Brazilian brown seaweed Sargassum vulgare were extracted with chloroform/methanol 2:1 and 1:2 (v/v) at room temperature. After performing Folch partition of the crude lipid extract, the lipids recovered from the Folch lower layer were fractionated on a silica gel column eluted with chloroform, acetone and methanol. The fraction eluted with methanol, presented a strong orcinol-positive band characteristic of the presence of sulfatides when examined by TLC. This fraction was then purified by two successive silica gel column chromatography giving rise to fractions F4I86 and F4II90 that exhibited strong activity against herpes simplex virus type 1 and 2. The chemical structures present in both fractions were elucidated by ESI-MS and 1H/13C NMR analysis HSQC fingerprints based on their tandem–MS behavior as sulfoquinovosildiacylglycerols (SQDGs). The main SQDG present in both fractions and responsible for the anti-herpes activity observed was identified as 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-d-quinovopyranosyl)-glycerol.  相似文献   
169.
AIM: To assay antiviral effects of the polysaccharide and separated products from Sargassum fusiforme on herpes simplex virus type 1 (HSV-1) and coxsackie virus (CVB3) and their antiviral mechanism. METHODS: The antiviral effects of all extracts from Sargassum fusiforme on HSV-1 and CVB3 and their cytotoxicity on Vero cells were studied by CPE and MTT methods. Antiviral mechanism of two extracts was also investigated by four different ways. RESULTS and CONCLUSION: ① The cytotoxicity of extracts on Vero cells was undetectable (CC50>5 000 mg/L). ② All extracts except algin (ALG) had an obviously HSV-1 inhibitory effect. Antiviral activities of them were increasingly strengthened with their purities. Antiviral activities of extracts from flucoidan 1, F1, F2 and F4 were better than acyclovir (ACV). ③ Antiviral activities of all extracts on CVB3 were better than ribavirin injection. F1, F2 and F4 had remarkable anti-CVB3 effects. ④ The experiment showed that Sargassum fusiforme polysaccharides not only kill the above viruses directly but also restrain them via getting into cells or absorbing on cells.  相似文献   
170.
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