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151.
激素处理对杨桐扦插生根的影响   总被引:2,自引:0,他引:2  
通过杨桐扦插激素处理试验表明,NAA处理对杨桐扦插生根有极显著的影响,几种处理中,以100mg/L处理24h和500mg/L处理10S最好,扦插生根率分别达到85%和79.5%,比对照分别高出23.5%和18.0%。杨桐扦插生根属皮部生根型。  相似文献   
152.
通过对我省湘南低山丘陵区红壤土、石灰土、钙质土立地条件下 ,批杷优良品种丰产栽培技术试验林、示范林的调研及相关资料的系统分析研究 ,提出了枇杷在我省湘南低山丘陵区红壤、石灰岩、钙质页岩地区配套的优质丰产、高效栽培技术体系 :因地整地、合理施肥、疏花疏果、果实套袋、抓好夏季修剪、防治病虫害等  相似文献   
153.
 Parasitism by parasitoid wasps on the larvae of Epinotia granitalis (Butler), which is a wood-injuring pest in coniferous plantations, was observed for 6 years in two plantation forests of Chamaecyparis obtusa (Sieb. et Zucc.) Endl. and Cryptomeria japonica (L.f.) D. Don that were adjacent to each other and consisted of trees of almost the same size. E. granitalis larvae were collected from early April to mid-May, then reared in glass bottles, and finally examined to determine whether or not the larvae had been parasitized. Five species of parasitoids were recorded; two of them were classified in Ichneumonidae, Campoplex spp. A and B, and others in Braconidae, Iconella repleta Papp, Bassus cingulipes Nees von Esenbeck, and Bracon spp. In all 6 years, parasitism was first observed around 20 April. Species composition of parasitoids differed greatly among years and between forests. In 1 year in each forest the percentage parasitism increased significantly with the sampling date, indicating that not all parasitoids attack the same developmental stage of E. granitalis. The mean percentage parasitism per year was significantly higher in the forest of C. obtusa [11.5(%) ± 5.7(SD)] than in the forest of C. japonica (3.0 ± 4.1). These results suggest that the efficiency of parasitoid adults in finding hosts differed between the two forests. Received: September 20, 2001 / Accepted: August 5, 2002 Acknowledgments We are grateful to Dr. K. Maeto, Shikoku Research Center, Forestry and Forest Products Research Institute, and to Dr. K. Konishi, National Agricultural Research Center for Hokkaido Region, for identifying parasitoids, and to Dr. T. Miyaura, Forest Tree Breeding Center, and Dr. H. Kosaka, Forestry and Forest Products Research Institute, for their helpful advice throughout the study. Correspondence to:K. Kato  相似文献   
154.
银杏大蚕蛾的发生规律及防治措施   总被引:4,自引:0,他引:4  
江德安 《林业科技》2003,28(1):25-27
银杏大蚕蛾在湖北地区1年发生1代,以卵越冬,幼虫4-5龄为危害盛期。采取人工摘除虫茧、幼虫3龄前树冠喷Bt乳剂、树干钻孔注射内吸剂以及保护天敌等综合防治措施,能有效地控制该虫的发生与危害,虫口密度由原来的5-8头/100叶下降到0.8/100叶,防治效果达90%以上。  相似文献   
155.
目的 构建一套基于水稻重要性状基因标记的品种DNA指纹鉴定体系,为加强主栽优良食味半糯粳稻品种的种质管理与品种保护奠定基础。方法 以34个江浙沪主栽优良食味半糯粳稻品种为供试材料,通过已知标记多态性鉴定、公共数据库基因序列比对、基因组重测序等多种方法对水稻重要性状调控基因的关键差异位点进行筛选,开发核心SNP或InDel标记;利用As-PCR技术将SNP标记发展为依据电泳条带鉴别的简单PCR标记,通过电泳条带特征化和类型分析获得基因型信息,构建半糯粳稻品种的DNA指纹图谱库。结果 筛选出来源于40个水稻重要性状调控基因的54个核心标记,包括18个SNP标记和36个InDel标记;54个标记在20个品种中共检测到155个有效特征化条带,转化为155个0/1数据位点,建立各品种的DNA指纹数据库,可区分全部供试品种。遗传多样性分析表明,品种间遗传相似性变异范围为0.47—0.90,其中,南粳7718与苏香粳100的相似性系数最小,而南粳9308与南粳9036的相似性系数最大,二者存在8个数据位点差异。亲缘关系分析可将供试品种划分为6个分支,其中,南粳7718为独立分支,表明其与其他品种间的亲缘关系较远。核心标记鉴定效果的进一步验证表明,该套标记可以对14个半糯粳稻新品种进行有效区分,聚类图显示其分布于Ⅱ、Ⅲ和Ⅳ 3个类群,证实各品种间基因型信息的差异性;并利用该套标记鉴定了一个未知半糯水稻的品种真实性,根据基因型和聚类分析,将其判定为南粳9108。结论 经优化筛选,获得可准确区分当前主推半糯粳稻品种的54个核心标记,并发展为可电泳检测的简单PCR标记,利用该套标记组合构建了34个江浙沪地区主栽优良食味半糯粳稻品种的DNA指纹图谱。  相似文献   
156.
鳗鲡血液细胞的研究   总被引:17,自引:0,他引:17  
本文通过鳗鲡血液有形成份Wright染色并进行显微分析,辩识其红血细胞、嗜中性粒细胞、嗜酸性粒细胞、嗜碱生粒细胞、小淋巴细胞、单核细胞和血栓细胞并加以分析。  相似文献   
157.
Electrophysiological studies in vitro demonstrated the significant inhibition by natriuretic peptides (NP) of short-circuit current across the eel intestine, an important osmoregulatory organ. Inhibitory potencies of several members of the NP family were assessed by voltage-clamp determination of net transepithelial salt absorption measured as the short-circuit current Isc across the intestine of the freshwater-adapted (FW) and seawater-adapted (SW) Japanese eel (Anguilla japonica); the order of potency of synthetic eel peptides was: amidated atrial natriuretic peptide (ANP-NH2) > ventricular natriuretic peptide (VNP) > atrial natriuretic peptide (ANP) >> C-type natriuretic peptide (CNP). Neither the order of potency nor the absolute potencies were effected by salinity adaptation. The observed potency sequence suggests that inhibition of intestinal absorption is mediated by A-type guanylyl cyclase-coupled NP receptors. The relatively low sensitivity of the intestinal response to NP compared with circulating NP concentrations suggests a role for intestinal regulation by NP which is independent of systemic delivery from cardiac sources. A novel model, incorporating the known immunohistochemical localization of NP-ergic cells and processes in the epithelial layer of the intestine and the dissipation of the Na+ electrochemical gradient along the alimentary tract, is developed in which local secretion of NP (in response to a bolus of food) inhibits salt absorption across the intestine regionally in favor of increased nutrient absorption.  相似文献   
158.
Rod cells proliferate in the eel retina throughout life   总被引:1,自引:0,他引:1  
  相似文献   
159.
本试验旨在建立一种在日本鳗鲡脾脏抗菌肽分离纯化过程中简便、灵敏的检测其抗菌活性的方法。试验以日本鳗鲡脾脏分子质量小于10 ku的蛋白质为抗菌肽样品,选择琼脂板孔穴扩散法和微孔液体培养法2种传统方法及微量液体培养法为检测方法,比较这3种方法在抗菌肽对3种鳗鲡常见致病菌株(迟钝爱德华菌、气单胞菌、嗜水气单胞菌)抗菌活性检测中的灵敏度和优缺点。结果表明:与琼脂板孔穴扩散法及微孔液体培养法相比,微量液体培养法简便、易于观察结果,具有最高的灵敏度且样品用量最少,适合在鳗鲡脾脏抗菌肽分离纯化过程中跟踪检测抗菌活性,尤其适合分离纯化后期获得微量单一样品抗菌活性的检测。由此得出,微量液体培养法适用于检测日本鳗鲡脾脏抗菌肽的抗菌活性。  相似文献   
160.
Restorer line breeding is an important approach to enhance the heterosis and improve the yields of japonica hybrid rice. To improve the selection efficiency of restorer lines for BT-type cytoplasmic male sterility (CMS) in japonica rice, a functional marker InDel-Rf-1a based on the difference of nucleotide sequence in Rf-1a locus between BT-type CMS lines and restorer lines was developed to detect the genotypes of different rice materials. Conventional indica rice varieties, restorer and maintainer lines without 574 bp deletion could restore the fertility for BT-type CMS in japonica rice. By contrast, most conventional japonica rice varieties except Aichi 106 and Yijing 12, with genotype of rf-1arf-1a showed the 574 bp deletion maintained sterility for BT-type CMS lines. To further verify the effect of genotyping detection in Rf-1a locus, this marker was also used to amplify the genomic DNA in different japonica rice restorer lines, CMS lines, hybrids and F2 segregation population, and three genotypes in Rf-1a locus could be distinguished distinctly. Therefore, the marker InDel-Rf-1a could be widely used for genetic identification and marker-assisted selection (MAS) in breeding japonica restorer lines.  相似文献   
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