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151.
A method of digestion by using a mixture of hydrochloric, nitric, and sulfuric acids has been developed for the determination of total mercury in a wide range of food samples. Good recoveries of mercury were obtained from NBS (National Bureau of Standards) Albacore Tuna and from food samples spiked with inorganic mercury. A detection limit of 0.01 microgram mercury/g can be obtained.  相似文献   
152.
Geographical distribution of vampire bat-related cattle rabies in Brazil   总被引:6,自引:0,他引:6  
Seventy-seven rabies virus (RV) isolates originating from Brazilian cattle were genetically characterized. Partial nucleoprotein gene sequences of these isolates were phylogenetically and geographically analyzed. Cattle isolates, which clustered with the vampire bat-related RV group, were further subdivided into nine genetic subgroups. These subgroups were distributed widely in lowland regions, with some subgroups separated from each other by mountain ranges. In addition, separation of the groups in mountainous regions was correlated with altitude. These results indicate that cattle rabies is derived from several regionally-defined variants, which suggests that its geographical distribution is related to that of the vampire bat population.  相似文献   
153.
The effect of edible seaweeds [nori (Porphyra tenera) and wakame (Undaria pinnatifida)] on the modulation of colonic microbiota was studied in adult male Wistar rats. Each alga was fed to rats as the only source of dietary fiber and compared with cellulose. After 12 days, animals were sacrificed and cecal contents used as inoculum to ferment lactulose, citrus pectin, cellulose, nori, and wakame in vitro. Dietary treatment did not affect food intake or food efficiency, yet alga caused a significant increase in cecal weight. Nori and wakame were poorly fermented by the cellulose inoculum, with intermediate substrate degradation (76 and 57% for nori and wakame, respectively) and low metabolism to short-chain fatty acids (SCFA) (30% fermentability compared with lactulose). Cecal contents from rats fed nori and wakame showed a reduced ability to ferment all of the studied substrates compared with the cellulose inoculum, causing a reduction in SCFA production and dry matter disappearance. Only nori induced a bacterial adaptation that brought about a higher fermentation of this substrate. The different behaviors of the two algae could be due to their distinct chemical compositions. In conclusion, nondigestible components of edible seaweeds modified the metabolic activity of intestinal microflora, leading to a reduction of its fermentative capacity.  相似文献   
154.
Paddy and Water Environment - Technological and socioeconomic interventions accompanied by climate warming strongly dictate farming practices, lending a direct impact over future irrigation water...  相似文献   
155.
Natural polysaccharides exhibit beneficial immune modulatory effects, including immune stimulatory and anti-cancer activities. In this study, we examined the effect of Codium fragile polysaccharide (CFP) on natural killer (NK) cell activation, and its effect on tumor-bearing mice. Intravenous CFP treatment of C57BL/6 mice resulted in the upregulation of CD69, which is a marker associated with NK cell activation. In addition, intracellular levels of interferon (IFN)-γ and the cytotoxic mediators perforin and granzyme B were markedly increased in response to the CFP treatment of splenic NK cells. IFN-γ production by NK cells was directly induced by CFP, whereas the upregulation of CD69 and cytotoxic mediators required IL-12. Finally, intraperitoneal treatment with CFP prevented CT-26 (murine carcinoma) tumor cell infiltration in the lungs, without significantly reducing the body weight. In addition, treatment with CFP prevented B16 melanoma cell infiltration in the lung of C57BL/6 mice. Moreover, the anti-tumor effect was diminished by the depletion of NK cells. Therefore, these data suggest that CFP may be used as an NK cell stimulator to produce a phenomenon that contributes to anti-cancer immunity.  相似文献   
156.
Atopic dermatitis (AD) is a chronic inflammatory skin disease. Juniperus Chinensis heartwood has been known to have an excellent antibacterial and anti-inflammatory effect. This study examined the potential of the methanol extract of the Juniperus Chinensis heartwood as a natural dye with an efficacy for the treatment of atopic dermatitis. In an attempt to examine the effect of the Juniperus Chinensis heartwood extract, a skin lesion such as that of AD was induced in the NC/Nga AD mice model by topical administration. DNCB (2.4-dinitrochlorobenzene) was used to induce such AD-like skin lesions. The efficacy of the Juniperus Chinensis heartwood extract in the NC/Nga mice model was assessed by severity of skin lesion (NC mouse score), change in organ weight, serum IgE level, change in epidermal thickness, and mast cell count. The Juniperus Chinensis heartwood extract improved such skin lesions in these NC/Nga mice, and decreased spleen weight and serum IgE level. The results of histopathologic examination revealed that the treatment with the Juniperus Chinensis heartwood extract decreased epidermal thickness and mast cell count. In conclusion, the suppressive effect of local administration of the Juniperus Chinensis heartwood extract verified its potential for application as a natural dye with an efficacy of treatment for atopic dermatitis.  相似文献   
157.
几种药剂对玉米三点斑叶蝉的毒力及田间防治效果   总被引:1,自引:0,他引:1  
采用微量点滴法测定了达福、康福多、一遍净和辛硫灭扫利等 4种药剂对玉米三点斑叶蝉的毒力 ,结果表明 :一遍净和康福多对玉米三点斑叶蝉毒力较强 ,LC50 分别为 2 3 .68mg·kg- 1 和 31 .41mg·kg- 1 ,其次为辛硫灭扫利 69.1 2mg·kg- 1 和达福 1 0 7.82mg·kg- 1 。田间试验结果表明 ,防治后 7d ,达福、康福多和辛硫灭扫利的防效仍保持在 98.1 3 % ,86 .50 %和 90 .67% ;防治后 1 4d ,达福的防效仍较高为 91 .31 % ,其次为康福多和一遍净 ,分别为 81 .31 %和 73 .2 1 %。  相似文献   
158.
Dietary fiber and bioactive compounds are widely used as functional ingredients in processed foods. The market in this field is competitive and the development of new types of quality ingredients for the food industry is on the rise. Opuntia ficus-indica (cactus pear) produces edible tender stems (cladodes) and fruits with a high nutritional value in terms of minerals, protein, dietary fiber and phytochemicals; however, around 20% of fresh weight of cladodes and 45% of fresh weight of fruits are by-products. The objective of this study was therefore to determine the nutritional value of by-products obtained from cladodes and fruits from two varieties of Opuntia ficus-indica, examining their dietary fiber and natural antioxidant compound contents in order to obtain quality ingredients for functional foods and increase the added value of these by-products.  相似文献   
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