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11.
本研究以中国野生葡萄14个种为材料,对控制花色苷合成的mybA转录因子进行克隆和序列分析,获得VvmybA1和VlmybA2两个转录因子的全长基因序列,共检测到121个SNP,表现出丰富的遗传多样性。3种中性检测方法比较序列变异模式,结果表明,中国野生种葡萄VvmybA1和VlmybA2基因没有偏离中性模型,反映出基因漂移和选择性中性突变之间的平衡。不同野生种材料的mybA 基因结构存在很高的同源相似性。但是在启动子区、内含子区以及第三个外显子区存在不同程度碱基的缺失、插入和替换,而且野生种葡萄mybA基因存在一些特有序列或突变,这些突变可以作为分子标记区分不同的野生种材料。通过基因结构比对和系统进化树分析,可将野生种葡萄细分为5个类群。初步推测桦叶葡萄和变叶葡萄进化地位较为原始。  相似文献   
12.
高温胁迫下葡萄叶片蛋白激酶的诱导形成与活性变化   总被引:2,自引:0,他引:2  
以"京秀"葡萄(Vitis vinifera L.cv.Jingxiu)幼苗为试材,研究了高温胁迫激活的蛋白激酶的类型和活性.结果表明,高温胁迫10~60min明显地激活了一个分子量约为52 kD的蛋白激酶,该蛋白激酶能将凝胶中所嵌入的髓鞘碱性蛋白(MBP)磷酸化,在放射自显影中表现出很高的放射活性,而对凝胶中的组蛋白-Ⅲ(histone-Ⅲ)则没有这样的作用.在溶液反应体系中该蛋白激酶对MBP也表现出很高的磷酸化活性,而对histone-Ⅲ却无作用.Ca2 对其活性变化无显著影响.酪氨酸特异性蛋白磷酸酶(YOP)对该激酶的活性有显著的钝化作用.结果表明该52 kD蛋白激酶是MAPK家族中的一种.  相似文献   
13.
Succinate dehydrogenase inhibitor (SDHI) fungicides constitute a relatively recent fungicide class registered for the treatment of grey mould on grapevine in Italy. The sensitivity profile to a novel compound fluopyram was established for a set of 203 Botrytis cinerea isolates collected from Sicilian vineyards within 2009–2012 prior its introduction into market. In addition, its performances were compared in in vitro and in vivo assays with other registered SDHI fungicide boscalid, to evaluate their frequency distributions EC50 values and cross‐resistance patterns. Results of the article showed that EC50 values for fluopyram ranged from 0.05 to 1.98 µg mL?1. Although EC50 values of boscalid ranged from 0.01 to 89.52 µg mL?1, no cross‐resistance relationship was observed between the two fungicides (r = 0.003; P = 0.964) within our B. cinerea population. On further confirming these data, boscalid failed in controlling grey mould infections when boscalid‐resistant isolates were inoculated on grape berries whereas fluopyram exhibited a good efficacy against the same isolates. This study represents the first report on the baseline sensitivity to fluopyram within B. cinerea population from Sicilian table grape vineyards in Italy, and it clearly shows the lack of cross‐resistance in vitro and in vivo between fluopyram and boscalid for the field pathogen isolates. These results provided useful information for managing of fungicide resistance suggesting that fluopyram could be a valid alternative to boscalid for the control of grey mould of table grape.  相似文献   
14.
The present study aimed to investigate the effects of different levels of dietary supplementation of grape seed extract (GSE) on growth performance, carcass traits and antioxidant status of rabbits under heat stress conditions (temperature humidity index 87.5–93.5). Weaned male New Zealand White (NZW) rabbits about 6 weeks old (n = 144, mean body weight 705 g) were randomly allotted to four dietary groups. The Control group was fed a basal diet without GSE; the experimental groups received the basal diet with 100, 200 and 300 mg GSE/kg (Groups 100 GSE, 200 GSE and 300 GSE, respectively). The experimental period lasted for 8 weeks. Compared with other groups, rabbits of Group 300 GSE had the best body weight gain and feed conversion ratio and the lowest mortality. Dietary GSE improved carcass weight, percentage of hot carcass, intestine and edible giblets, while total non-edible parts were reduced (p ≤ 0.05) in comparison with the Control group. In Groups 200 GSE and 300 GSE, plasma total protein, albumin and globulin were increased (≤ 0.05). In contrast, all supplementation levels of GSE reduced (≤ 0.05) the plasma concentrations of total lipids, total cholesterol, triglycerides and low-density lipoproteins. Antioxidant enzymes of rabbits (superoxide dismutase, catalase, glutathione peroxidase, glutathione transferase) and total antioxidant capacity in blood were increased (≤ 0.05) by adding dietary GSE. However, malondialdehyde was reduced (≤ 0.001) with increasing GSE levels. Generally, grape seeds can be considered as rich source of phenolic and flavonoid compounds. The results of the study revealed that all tested levels of GSE were useful as a natural protection against heat stress to maintain performance, carcass traits and antioxidant status and could reduce the negative effects of heat stress in rabbits.  相似文献   
15.
蔗糖转化酶(invertase, INV)在植物生长发育和抵御胁迫中发挥着重要作用。研究从葡萄基因组数据库中鉴定出19个蔗糖转化酶基因,对基因结构和编码蛋白质的理化性质进行生物信息学分析,并利用qRT-PCR技术分析基因在不同激素和非生物胁迫条件下的表达特征,为进一步探索葡萄INV基因家族参与葡萄逆境响应提供了一定的理论依据。结果表明,(1)该基因家族编码蛋白的氨基酸长度在150~766 aa之间,理论等电点介于4.43~9.1之间,亚细胞定位预测发现其主要在细胞质中表达,此外液泡和细胞壁也存在部分基因表达;(2)共线性结果显示VvCINV与其他5个物种复制频率较高;(3)保守基序分析表明VvCwINV包含了所有的保守基序,且Glyco_32和Glyco_hydro_100是VvINV基因主要结构域;(4)组织特异性表达分析发现多数基因在葡萄生长发育进程中都有表达;(5)qRT-PCR分析结果显示,VvINV基因家族在叶片中对激素处理和非生物胁迫的响应出现上调,VvCINV1在50 mg/L GA3和10%PEG处理后上调表达极显著,VvCINV4在盐胁迫、ABA...  相似文献   
16.
本文利用甲醇溶剂对酿酒葡萄皮渣进行浸提,得到白藜芦醇粗提物.粗提物通过硅胶柱层析进行纯化.然后,研究了白藜芦醇的氧自由基、超氧阴离子自由基、羟自由基、DPPH自由基的清除能力.结果显示:白藜芦醇具有很强的自由基清除能力和抗氧化能力,并且随着浓度的增加,抗氧化能力增强.  相似文献   
17.
The roles of polyamines (PAs) in the development of seedless grape berries induced by gibberellin (GA3) was investigated. The development of seedless grape berries was stimulated by the application of putrescine (Put), but not by that of spermidine (Spd) and spermine (Spm), regardless of the presence of GA3. At harvest, the fresh weight of seedless grape berries treated with 500 ppm Put + 25 ppm GA3 and 500 ppm Put increased to 111 and 112%, respectively, of the control. Treatment with methylglyoxal-bis (guanyl hydrazone), a potent inhibitor of S-adenosylmethionine decarboxylase that plays a role in Spd and Spm synthesis, did not affect the development of seedless grape berries induced by 100 ppm GA3. The application of 100 ppm GA3 significantly increased endogenous free Put levels. Levels of free Spd and Spm were not affected by GA3. Although the levels of endogenous perchloric acid insoluble bound PAs were higher than those of free PAs, obvious changes in the levels of bound PAs were not observed. These results indicate that free Put is implicated in the development of seedless grape berries induced by GA3.  相似文献   
18.
采用固相微萃取技术及气相-质谱联用技术对不同SO2漂白伤害程度的红提果实进行香气成分的提取与鉴定,以探讨SO2漂白伤害对贮藏葡萄果实中香气组分的影响.结果表明,果实经漂白伤害后其具有芳香气味的气体所占比重明显下降,主要成分醇类化合物下降最多,而具有刺激难闻气味的酸类化合物所占比重明显上升;此外,4-萜烯醇、正己醇、月桂醇、松油醇、芳樟醇、橙花醇、乙酸萜烯酯及青叶醛等具有葡萄特征性香味的化合物在香气中所占比例明显下降或消失,而异辛醇、1-辛烯-3-醇、壬酸、辛酸、正癸酸、乙酸、己酸、2,6-二叔丁基对甲酚及2-丁基-5-(2-甲基丙基)-噻吩等具有臭味或刺激性气味的化合物出现或所占比重上升.说明,SO2伤害对红提果实香气的影响主要表现为香味化合物所占比重的减少或消失及异味化合物的产生.  相似文献   
19.
The progression of diabetic cardiomyopathy is related to cardiomyocyte dysfunction and apoptosis. Our previous studies showed that asporin (ASPN) was significantly increased in the myocardium of db/db mice through proteomics, and grape seed procyanidin B2 (GSPB2) significantly inhibited the expression of ASPN in the heart of db/db mice. We report here that ASPN played a critical role in glycated low‐density lipoproteins (gly‐LDL) induced‐cardiomyocyte apoptosis. We found that gly‐LDL upregulated ASPN expression. ASPN increased H9C2 cardiomyocyte apoptosis with down‐regulation of Bcl‐2, upregulation of transforming growth factor‐β1, Bax, collagen III, fibronectin, and phosphorylation of smad2 and smad3. However, GSPB2 treatment reversed ASPN‐induced impairments in H9C2 cardiomyocytes. These results provide evidence for the cardioprotective action of GSPB2 against ASPN injury, and thus suggest a new target for fighting against diabetic cardiomyopathy.  相似文献   
20.
In 2013, bitter rot of grape was observed in Changbei Vineyard located in Nanchang City, Jiangxi Province, China. Greeneria species was consistently isolated from the diseased grape berries (Vitis labruscana cv. Kyoho) at approximately 91% of isolation rate in three independent experiments. The species was identified as Greeneria uvicola based on the morphological characteristics, cultural appearance and sequence analysis. Koch's postulates were fulfilled through pathogenicity tests on detached healthy Kyoho grape berries. To our knowledge, this is the first report of G. uvicola causing bitter rot of grape in China.  相似文献   
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