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91.
WANG Xin-shi ZENG Qing-yi ZHU Zhen-guo ZHU Pan XU Hui-qin ZHENG Rong-yuan 《园艺学报》2014,30(12):2254-2258
AIM:To study the effect of idazoxan (IDA) on the permeability of blood-brain barrier (BBB) and the expression of matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1) in mouse experimental autoimmune encephalomyelitis (EAE).METHODS:Female C57BL/6 mice (n=36) were randomly divided into control group, EAE group and IDA group, with 12 mice in each group. EAE was induced by myelin oligodendrocyte glycoprotein 35-55 (MOG35-55). IDA (2 mg/kg, ip, bid) was administered for 15 d after immunization. The neurological defects of the mice were observed daily and scored. The pathological changes were observed under microscope with HE staining and LFB myelin staining. The BBB permeability was detected by Evans blue extravasation. The expression of MMP-9 and TIMP-1 in the brain of EAE mice was determined by Western blotting.RESULTS:Compared with EAE group, the score of neurological defects in IDA group was decreased, the inflammation was relieved, the BBB permeability was reduced, and the expression MMP-9 and the ratio of MMP-9/TIMP-1 were decreased (P<0.05).CONCLUSION:The neuroprotective effect of IDA on mouse EAE might be related to the down-regulation of MMP-9 and the ratio of MMP-9/TIMP-1, thus reducing the degradation of BBB and the permeability of BBB, and ameliorating the pathologic process of EAE. 相似文献
92.
[目的]为进一步提高烤烟的产质量奠定良好的基础.[方法]以烟草CB-1品种为供试材料,以联农(x)等11种化学抑芽剂为供试药剂,通过田间试验对比了不同抑芽剂的抑芽率、抑芽效果及药害程度.[结果]芽封(25%氟节胺可分散油悬浮剂)的综合抑芽效果最好,食盐的抑芽综合效果最差.不同抑芽剂都未造成各试验小区的药害.抑芽敏(氟节胺)、除芽通(33%二甲戊灵乳油)、芽畏(仲丁灵37.3%乳油)、盾牌烟舒(仲灵&#183;异噁松)、菜草通(33%二甲戊灵)等的抑芽综合效果均较好,抑芽率均高于83%,抑芽效果均高于89%.[结论]该研究可为筛选安全、高效、低成本的烟草抑芽剂提供试验依据. 相似文献
93.
硝化抑制剂对小白菜生长和土壤性质的影响 总被引:2,自引:1,他引:1
施用硝化抑制剂可有效控制蔬菜硝酸盐积累,施用硝化抑制剂DMPP、土地精和双氰胺可提高小白菜的经济产量、叶面积、净光合速率,降低硝酸盐含量,并对栽培土壤有明显的改良作用。硝化抑制剂对小白菜的硝酸盐积累抑制作用为DMPP双氰胺土地精,3种硝化抑制剂在经济产量方面表现为DMPPDCDTC,比对照分别提高产量19.32%、14.83%、9.46%。对叶茎鲜重比的影响结果为DCD(84.7%)DMPP(84.4%)TC(83.8%)CK(78.1%)。通过对栽培土壤的研究发现硝化抑制剂能显著改良土壤的盐渍化,降低小白菜生长过程中土壤盐离子的含量,提高铵离子在土壤中的含量,抑制土壤耕层硝酸盐的生成。 相似文献
94.
95.
V. S. Babar J. K. Chavan S. S. Kadam 《Plant foods for human nutrition (Dordrecht, Netherlands)》1988,38(4):319-324
The application of dry heat to seeds and meal was not effective in inactivating the TI and reducing the polyphenol content. Soaking for 24 h followed by cooking for 20 min, was equally effective in destroying the TI activity. Germination of jack bean seeds for 40 h decreased the levels of TI and polyphenols by 31% and 35%, respectively. 相似文献
96.
H. Goesaert K. Gebruers K. Brijs C. M. Courtin J. A. Delcour 《Journal of Cereal Science》2003,38(3):317-324
Highly pure XIP-type (for Xylanase Inhibiting Protein) endoxylanase inhibitor fractions were selectively obtained with a high yield from rye, durum wheat, barley, and maize extracts by affinity chromatography with immobilised Aspergillus niger endoxylanase Xyn1 following removal of the TAXI-type (for Triticum aestivum xylanase inhibitor) endoxylanase inhibitors by affinity chromatography with immobilised Bacillus subtilis endoxylanase XynA. No inhibitors belonging to the XIP family occur in rice, oats, and buckwheat. N-terminal amino acid sequences of the non-wheat XIP-type inhibitors were very similar or identical to those of wheat XIP-1, a chitinase homologue. The isolated inhibitors are basic, monomeric proteins of ca. 30 kDa with pI values of at least 8.5 (rye, durum wheat, and barley XIP) and ca. 7.0 (maize XIP). They are, in general, active against fungal endoxylanases and do not hydrolyse chitin. SDS–PAGE analysis and high-resolution cation exchange chromatography suggest the presence of multiple XIP-type isoinhibitors in the different cereals. 相似文献
97.
V. H. Mulimani S. Vadiraj 《Plant foods for human nutrition (Dordrecht, Netherlands)》1994,46(1):27-31
Changes in trypsin and chymotrypsin inhibitory activity of sorghum (Sorghum bicolor L. Moench) seeds on soaking in distilled water, different salt solutions and mixed salt solution were investigated. A greater reduction in proteinase inhibitory activity was observed on soaking in salt solution than on soaking in distilled water. Maximum loss of trypsin and chymotrypsin inhibitory activity was observed on soaking seeds in mixed salt solution. 相似文献
98.
Alka Sharma Salil Sehgal 《Plant foods for human nutrition (Dordrecht, Netherlands)》1992,42(2):127-133
The effects of domestic processing methods like soaking for 12 h dehulling, ordinary cooking of whole as well as dehulled seeds at 151bs/inch2 pressure for 15 and 25 min, and germination for 24, 36 and 48 h were observed on trypsin inhibitor (TIA) and tannin content of two varieties of faba bean viz. VH-131 and WF. A non-significant reduction in TIA was observed on soaking and dehulling, while tannins showed a reduction of 42 and 51% on soaking in VH 131 and WF, respectively. Dehulled seeds showed a decline in tannin content by 70 to 73% in two varieties. There was a significant reduction in TIA (75–76 per cent) and tannin (76–81%) on cooking, while autoclaving for 25 min almost completely eliminated both of these stress factors. Germination of seeds for 48 h led to a reduction of 64–65% in TIA and 90–91% in tannins, which was more than germination for 24 and 36 h. Soaked seeds gave positive results of both these antinutrients. 相似文献
99.
In order to understand the extent of elimination of trypsininhibitors during processing of sweet potato (Ipomoea batatas) andtaro (Colocasia esculenta) tubers, a detailed study was conductedusing tubers processed by oven drying, cooking, and microwavebaking. Between 80 and 90% trypsin inhibitor (TI) activity wasretained in sweet potato chips up to 2h at 70 °C. Among thefour cultivars of sweet potatoes, RS-III-2 trypsin inhibitors were more heatlabile. Heating at 100 °C led to rapid inactivation of TI of sweetpotatoes. Varietal differences in thermal stability were more pronouncedfor the trypsin inhibitors of taro than sweet potatoes. Taro inhibitors werealso more rapidly inactivated than sweet potato TI. Between 17 and31% TI activity was retained in cooked tuber pieces of sweet potatoes,while only 3–10% were retained in taro cultivars. Very effectiveinactivation of trypsin inhibitors of sweet potatoes and taro could beobtained through microwave baking. Flour prepared from taro was devoidof TI activity, while 5–12% TI activity was retained in the flour preparedfrom sweet potatoes. The study clearly established that among the fourtechniques used, microwave baking and flour preparation were the best methods to eliminate TI from sweet potatoes and taro. 相似文献
100.
ASI是抑制小麦α-淀粉酶活性及改善小麦品质的一种重要蛋白,目前已将编码ASI蛋白的基因定位于麦类作物第二同源染色体的长臂上。ASI蛋白具有高度的多态性。大麦中ASI蛋白对小麦α-淀粉酶的活性抑制作用较强,在小麦中导入大麦ASI蛋白基因能够延缓小麦穗发芽。抗ASI蛋白的单克隆抗体具有特异性,依赖抗小麦ASI蛋白的ELISA是测定ASI蛋白浓度的一种有效方法。本文对α-淀粉酶抑制蛋白的特性及应用进行 相似文献