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21.
以“秦美”猕猴桃果实呼吸跃变初期cDNA第一链为模板,参考大麦钙调蛋白基因序列合成5′端和3′端引物,利用多聚酶链式反应(PCR)合成了完整的猕猴桃钙调蛋白cDNA,克隆并测定了其全序列。结果表明,猕猴桃钙调蛋白基因读码框架内序列由444个核苷酸组成,共编码148个氨基酸,且与植物领域里发表的大麦及苜蓿的钙调蛋白基因有很高的同源性。在核苷酸序列上与大麦有86.16%的同源性,与苜蓿有85.69%的同源性,其编码的氨基酸与大麦和苜蓿的不同分别只是一个氨基酸的差异,同源率高达99.3%.  相似文献   
22.
产后果实病害生物防治的研究进展   总被引:3,自引:0,他引:3       下载免费PDF全文
果实产后病害严重影响水果的贮藏及商品质量,使用杀菌剂防治这类病害,因受到各种原因的影响而限制使用.产后果实生物防治(BCPD)作为一种有效的替代方法越来越受到人们的重视,因为果实产后系统具有环境因素的可控性、生物防治的安全性和稳定性等特点.作者从果实产后系统的特点、拮抗菌的筛选方法、生防机制、提高生物防治效果的措施和生物防治的发展前景等几方面进行阐述,展示产后果实病害生物防治的可行性和潜力,并为今后生防产品的开发提供研究思路.  相似文献   
23.
本研究共分离了976株细菌分离物,发现来自甘蔗根围的1株枯草芽孢杆菌(Bacillus subtilis)S9对立枯丝核菌(Rhizoctonia solani)、终极腐霉(Pythium ultimum)和西瓜枯萎病菌(Fusarium oxysporum f.sp.niveum)在PDA平板的对峙培养过程中不形成抑菌圈,但4d后可使上述植物病原真菌的菌丝溶解。扫描电镜观察发现S9菌株在待测的立枯丝核菌表面形成了溶菌斑。S9菌株对立枯丝核菌的作用过程是通过吸附在病原真菌的菌丝上,并随菌丝生长而生长,而后产生溶菌物质消解菌丝体。液体共培养测定也证明了S9菌株具有上述作用。本研究还发现,S9菌株对植物病原真菌的拮抗真菌绿色木霉(Trichoderma viride)、鲜红毛壳菌(Chaetomium cupreum)和球毛壳菌(Chaetomium globosum)的生长没有影响。盆栽试验证明了S9菌株可有效地控制立枯丝核菌(R.solani)引起的番茄苗期病害。S9菌株与其它拮抗真菌混合具有促进防治植物病原真菌引起的植物病害的潜力。  相似文献   
24.
1. The present study was conducted to investigate whether brain somatostatin increases feed intake in neonatal chickens. The mediating role of neuropeptide Y receptors on feed intake induced by somatostatin was investigated.

2. In this study, seven experiments were designed, each with four treatment groups (n = 44 in each experiment). In Experiment 1, chicks received control solution and 0.5, 1 and 2 nmol of somatostatin through intracerebroventricular (ICV) injection. In experiments 2, 3 and 4, chickens were ICV injected with control solution and 1.25, 2.5 and 5 μg of B5063 (NPY1 receptor antagonist), SF22 (NPY2 receptor antagonist) and SML0891 (NPY5 receptor antagonist), respectively. In experiment 5, 6 and 7 chickens received ICV injection of B5063, SF22, SML0891, with a co-injection of + somatostatin, control solution and somatostatin. The cumulative feed intake was measured until 120 min post injection.

3. Somatostatin significantly increased feed intake in FD3 chicks. Both B5063 and SML0891 dose-dependently decreased feed intake compared with the control group, while SF22 led to a dose-dependent increase in feed intake. In addition, the hyperphagic effect of somatostatin significantly decreased with co-injection of B560 plus somatostatin (p < 0.05), but SF22 and SML0891 had no effect on feed intake induced by somatostatin in chicks (p > 0.05).

4. Based on the results of this study, it is likely that somatostatin increased feed intake and NPY1 receptor acts as a mediator in hyperphagic effect of somatostatin in neonatal chicks.  相似文献   

25.
以零下低温锻炼和结合效应剂(CaCl2、钙离子螯合剂EGTA、钙离子通道阻断剂LaCl3或钙调素拮抗剂CPE)处理的低温锻炼下的中东扬扦插苗为试材,对其体内丙二醛(MDA)及钙调素CaM含量,SOD、POD及线粒体Ca^2-+ATPase活性分别进行测定。结果表明,低温锻炼不仅在一定程度下提高了幼苗CaM含量,提高了SOD、POD和Ca^2+-ATPase活性,降低了MDA含量;而且减少了低温胁迫所引起的SOD、POD,Ca^2++ATPase和CaM含量的下降程度以及MDA的增加幅度。在低温锻炼的同时。用CaCl2处理能加强低温锻炼的效果,但这种效应可被EGTA、LaCl3或CPZ处理抑制。经低温锻炼后,幼苗中的CaM含量的增加有助于SOD、POD和线粒体Ca^2+-ATPase活性的提高,进而对幼苗抗冻性的提高有明显的促进作用。  相似文献   
26.
AIM: This study was to utilize cholinergic antagonists to examine cholinergic pathway of soman-induced hypothermia. METHODS: Colonic temperature was measured at 60 min intervals with digital thermometer. Effect of peripheral muscarinic antagonist, methylscopolamine and central muscairnic antagonist, scopolamine on soman-induced hypothermia were observed in the rats. RESULTS: Administration of the soman (60 μg·kg-1, sc) led to a rapid reduction in body temperature. Administration of scopolamine (1 mg·kg-1, ip) markedly blocked the hypothermic effect of soman but administration of methyl scopolamine (1 mg·kg-1, ip) had no effect on the hypothermia. CONCLUSION: The data indicate that soman-induced hypothermia is mediated primarily through a central muscairnic pathway.  相似文献   
27.
以拟南芥和杨树的钙调蛋白氨基酸序列为探针,对橡胶树转录组数据库进行搜索,并设计引物进行PCR扩增,得到7个橡胶树钙调蛋白基因的cDNA序列,命名为HbCaM1-7。序列分析结果发现,HbCaM1-7的CDS序列均为450 bp,编码149个氨基酸,分子量为16.8 ku,等电点为3.95。其中,HbCaM1-6间氨基酸同源性为100%,HbCaM7与其他成员之间的氨基酸同源性为98%。在基因结构组织方面,HbCaM1-7均为一个内含子,且内含子的插入位置相同,但内含子的长度明显不同。从氨基酸序列同源性和进化关系分析结果可看出,钙调蛋白基因家族在进化上非常保守。在表达方面,HbCaM1-6在各组织中均有表达,除了HbCaM3在根中表达丰度相对较高,其他成员均在胶乳中表达丰度相对较高,而HbCaM7在各组织中的表达均比较低;乙烯利处理后,HbCaM2-7的表达均有一定的上升趋势,而在叶片发育过程中HbCaM1-5圴呈明显下调表达。由此可见,橡胶树钙调蛋白与橡胶树叶片发育、胶乳乙烯信号通路具有一定的相关性。  相似文献   
28.
通过酵母双杂交的方法寻找苹果‘国光’花柱中与S-RNase互作的非S因子。以苹果‘国光’花柱为试材,构建了酵母cDNA文库,检测插入片段大小在300~2 000bp之间,符合库容要求。将S1-RNase成熟区cDNA序列S1-mat构建到pGBKT7载体上作为诱饵,筛选‘国光’花柱酵母cDNA文库。经文库筛选,获得一个大小为371bp的片段,与苹果全基因组序列比对后发现,该片段位于第9号染色体,其全长序列为552bp。NCBI BLAST比对及蛋白结构域分析显示其与拟南芥钙调素结合蛋白的同源性最高,且具有钙调素结合蛋白特有的磷酸二酯酶结构域。同时,酵母互作实验显示其与‘国光’花柱钙调素(CaM)有强烈互作,故认为此基因是苹果钙调素结合蛋白基因,命名为MdCaMBP。半定量RT-PCR结果显示其在‘国光’叶片及花的各组织中均有表达,与苹果花柱S1-、S2-、S9-RNase成熟多肽区均有互作且作用强烈。推测MdCaMBP可能作为一种S-RNase辅助因子参与了自交不亲和反应。  相似文献   
29.
The effects of various Ca^2 -modifying drugs on moue egg fertilization were studied.Ca^2 chelator,ethylen glycol-bis-(2-aminoethyl)-tetracetic acid(EGTA),and calmodulin(CaM) antagonist,trifluoperzaine (TFP),inhibited fertilization in a dose-dependent manner,whild Ca^2 channel bolcker,verspamil,did not have any effect.When intracellular Ca^2 release was blocked by 8-(N,N-diethylamino) octy 1-3,4,5-trimethoxy-benzonate(TME-8) or the Ca^2 oscillations were inhibited by an inhibitor of endoplasmic reticulum Ca^2 -At-Pase,thapsigargin,the second polar body emission and pronuclear formation were significantly decreased.In contrast,inhibition of intracellular Ca^2 release via bolckage of inositol 1,4,5-triphosphate (IP3) production by neomycin or lithium did not affect fertilization.The results sugest that both extracellular influx,intracellular Ca^2 release and CaM activation are required for mormal fertilization.However,extracellular influx through voltage-gated Ca^2 channel and intracellular release induced by IP3 and not the only pathways for producing Ca^2 transients in moue eggs.  相似文献   
30.
Isolates of 85 bacteria and 94 streptomycete and 35 nonstreptomycete actinomycetes were obtained from a lettuce-growing field in Al-Ain, United Arab Emirates, on colloidal chitin agar, and screened for their ability to produce chitinase. Twenty-three bacteria and 38 streptomycete and 15 nonstreptomycete actinomycete isolates produced high levels of chitinase and were examined in vitro for their ability to suppress the growth of Sclerotinia minor , a pathogen causing basal drop disease of lettuce. The three most suppressive isolates were examined further for their production of β-1,3-glucanase and antifungal activity as well as their ability to colonize the roots and rhizosphere of lettuce in vitro and in planta . The three isolates, Serratia marcescens, Streptomyces viridodiasticus and Micromonospora carbonacea , significantly reduced the growth of S. minor in vitro , and produced high levels of chitinase and β-1,3-glucanase. Streptomyces viridodiasticus also produced antifungal metabolite(s) that significantly reduced the growth of the pathogen in vitro . When the pathogen was presented as the sole carbon source, all three isolates caused extensive hyphal plasmolysis and cell wall lysis. Serratia marcescens and St. viridodiasticus were competent to varying degrees in colonizing the roots of lettuce seedlings after 8 days on agar plates and the rhizosphere within 14 days in pots, with their competency being superior to that of M. carbonacea . All three isolates, individually or in combination, were antagonistic to S. minor and significantly reduced incidence of disease under controlled glasshouse conditions.  相似文献   
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