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不同葡萄品种膜质过氧化和保护酶活性对盐胁迫的响应 总被引:2,自引:0,他引:2
研究了不同浓度NaCl处理对双丰、左山二、贝达以及金玫瑰细胞膜透性、膜质过氧化和保护酶活性的影响。结果表明:不同处理间,4个品种耐NaCl胁迫的动态响应表现出显著差异。随胁迫浓度的增大和胁迫时间的延长,MDA含量和细胞膜透性表现出增高趋势,增高幅度由高到低的顺序为双丰、左山二、贝达、金玫瑰;保护酶SOD活性整体表现出先增后降趋势,金玫瑰和贝达升高幅度相对较大;POD活性整体表现出下降趋势,但金玫瑰和贝达下降幅度相对较小。 相似文献
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本研究以2010年武汉市全民体质监测数据为基础,对武汉市四个区的成年人体质健康现状和变化规律进行了调查和数据分析,以了解不同成年人组别、不同职业和性别群体成年人的体质差异。对照湖北居民参与体育锻炼情况的调查结果,本文探讨了成年人体质状况与体育活动之间的关联,以寻求改善成年人体质健康水平的有效途径和方法,为落实全民健身计划提供依据,提高全民健康尤其是成年人的健康水平。 相似文献
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S Aiumlamai G Fredriksson H Kindahl L E Edqvist L Kulander O Eriksson 《Research in veterinary science》1990,48(2):190-195
Injection of endotoxin from Salmonella typhimurium in male goats resulted in a biphasic release pattern of PGF2 alpha, as determined by 15-ketodihydro-PGF2 alpha concentrations in plasma. A small initial peak at 30 minutes was followed by a second peak one hour after injection. The rectal temperature increased three to five hours after endotoxin injection and calcium concentrations started to decrease soon after injection; a significant decrease was seen from 105 minutes. Endotoxin concentrations varied among the animals but had a tendency to increase three hours after injection, simultaneously with a decrease in bile acid concentrations three hours after injection. The decrease in bile acids indicated alimentary stasis. Therefore, the raised endotoxin levels could be of endogenous origin. This study also shows that the prostaglandin metabolite is a very reliable parameter for estimating the effect of endotoxin. 相似文献
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In order to explore the antibacterial activity and mechanism of the Radix isatidis powder water extract,the effects of the Radix isatidis powder water extract on the morphology and structure of Escherichia coli (E.coli) were tested by scanning electron microscopy and transmission electron microscopy.The effects of the Radix isatidis powder water extract on the conductivity and total leakage rate of E.coli and the content of alkaline phosphatase in the culture medium of the content of protein,DNA and RNA were stained by DAPI to detect the effect of the Radix isatidis powder water extract on the nucleic acid of E.coli,and the effect of the Radix isatidis powder water extract on the metabolism of E.coli in vivo,in vitro,ALT,AST,pyruvic acid and ATP.The results showed that after the Radix isatidis powder water extract acted on E.coli for 10 h,it was observed by SEM that the bacteria appeared to overflow and shrink,the length of the bacteria became shorter obviously,many residues were formed due to breakage,some of them were sunken in the middle and deformed.Under TEM,it was observed that the boundary of the cell wall of E.coli was unclear,the wall membrane was zigzag,deformed and some of the bacteria were broken.The protein content outside the cell was significantly different from that in the blank control group from 8 h (P<0.01), and that in the cell from 4 h (P<0.01). DNA content had no significant difference with blank control group before 12 h (P>0.05), but had significant difference with blank control group from 16 h (P<0.01); RNA content began to decrease at 8 h, and was significantly different from blank control group at 12 h (P<0.05), and was extremely significant from 16 h (P<0.01). There was no significant difference between ALT and AST (P>0.05). The pyruvate content in culture medium and bacteria was higher than that in blank control group, and the difference was very significant from 4 h (P<0.01). The ATP content in the culture medium was significantly different from that in the blank control group (P<0.01), and the ATP content in the cell was significantly different from that in the blank control group from 4 h (P<0.01).In conclusion,the Radix isatidis powder water extract could inhibit the synthesis and metabolism of bacterial genetic material and the content of pyruvate and ATP by destroying the integrity of cell wall and cell membrane. 相似文献
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目的观察澳洲茄胺盐酸盐对HeLa细胞c-myc,H—ras和hTRT基因表达的影响.方法用鼠抗人c-mycMcAb,H-ras McAb和hTRTPcAb作为一抗,生物素化羊抗鼠IgG作为二抗,用免疫组化方法测定澳洲茄胺盐酸盐对HeLa细胞c-myc,H—ms和hTRT基因的表达.结果澳洲茄胺盐酸盐处理的HeLa细胞与对照组相比,c-myc,H-ras和hTRT基因的表达均明显降低(P〈0.05).结论澳洲茄胺盐酸盐下调HeLa细胞c-myc和H-ras基因的表达,抑制细胞增殖,诱导分化;澳洲茄胺盐酸盐下调HeLa细胞hTRT基因的表达,抑制端粒酶活性,抑制细胞生长. 相似文献
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