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741.
家蚕血液中胰凝乳蛋白酶抑制剂研究--品种间的多态型 总被引:1,自引:0,他引:1
采用聚丙烯酰胺凝胶电泳和胰凝乳蛋白酶抑制剂(CI)活性染色,对9个家蚕品种血液中CI种类的分布进行了调整。结果:在碱性电泳条件下可检测出12种以上的CI,品种间CI分布存在多态型,根据结果筛选出作为分离纯化家蚕胰凝乳蛋白酶抑制剂的理想品种材料。 相似文献
742.
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744.
RYO KIMURA HIDEKI TAKAMI TSUNEO ONO TOSHIHIRO ONITSUKA YUKIHIRO NOJIRI 《Fisheries Oceanography》2011,20(5):357-366
We used an up‐to‐date, a high accuracy CO2 manipulation system to investigate the sensitivity of organisms to CO2 acidification, rearing marine calcifiers under elevated CO2 in running water. We evaluated the effects of elevated partial pressures of carbon dioxide (pCO2) in seawater on larvae of the commercially important marine gastropod Ezo abalone Haliotis discus hannai. In larval Ezo abalone, no effect of exposure to <1100 μatm pCO2 seawater was observed in fertilization, malformation, or mortality rates until 15 h after fertilization. However, compared to control larvae in seawater (450 or 500 μatm pCO2), the fertilization rate and the hatching rate (15 h after fertilization) decreased with increased pCO2 exposure (1650 and 2150 μatm pCO2) and the malformation rate increased significantly, with the larval shell length being smaller 75 h after hatching. These results suggest that ocean acidification will potentially impact the marine population of Ezo abalone as a human food source in the future. 相似文献
745.
ZHAO Hai-ping YIN Hong LI Chun-yi GAO Jin-liang LI You-quan GUAN Gui-quan LIU Zhi-jie LIU Jun-long YANG Fu-he XING Xiu-mei LUO Jian-xun 《中国农业科学(英文版)》2010,9(6):896-902
A primary cDNA expression library with a titer of 5.0 × 105 PFU mL-1 was constructed from mRNA extracted from larval Haemaphysalis qinghaiensis ticks in order to identify certain genes,which would then be used as candidate molecules for development of effective vaccines to control this parasite.Totally 11 positive clones,which designated as HqL01-11,were obtained by immunoscreening of the library using a polyclonal antibody generated in rabbit with larval tick protein extract.Results of sequence analysis from BLASTN searching revealed that 6 of them had no significant homology with the adult H.qinghaiensis ticks’ known genes,4 of them had no significant homology with all genes deposited in GenBank database.HqL07,HqL08,HqL09,and HqL11 were deposited to GenBank database,and accession numbers were EF605263,EF605264,EF605265,and EF605266,respectively.Subsequently,HqL07 and HqL09 were expressed in vitro and the molecular weights of the corresponding expressed products were 60 and 70 kDa,respectively.Western blot analyses showed that HqL07 and HqL09 had immunogenicity.This study laid the foundation for future production of genetically engineered vaccines for the immunological control of H.qinghaiensis. 相似文献
746.
Dynamics of total lipids and fatty acids during embryogenesis and larval development of Eurasian perch (Perca fluviatilis) 总被引:1,自引:0,他引:1
Total lipid and fatty acid compositions were determined during embryogenesis and larval development in Eurasian perch (Perca fluviatilis). During embryonic development, perch did not catabolize lipids and fatty acids as an energy source. However, during larval development, there was an exponential relationship between the decrease in total lipids and the duration of starving (r
2=0.9957) and feeding (r
2=1). The duration of the starving period (10 days post hatching) was shorter than the feeding period (35 days post hatching). In both starved and fed larvae, there is an apparent preference in utilization of polyunsaturated fatty acids followed by monounsaturated fatty acids. Saturated fatty acids were utilized by neither fed perch larvae nor by starved perch larvae. In starved larvae, palmitoleic 16:1(n-7) and oleic 18:1(n-9) acids were the preferentially monounsaturated fatty acids catabolized and their contribution as energy source from total fatty acids catabolized over the first week was 37.6%. In fed larvae, these 2 nutrients were also the most monounsaturated fatty acids utilized as energy source and possibly also as precursors for others monounsaturated fatty acids biosynthesis. During the same period and among (n-6) polyunsaturated fatty acids, starved perch utilized less linoleic 18:2(n-6) and arachidonic 20:4(n-6) acids than fed larvae despite the fact that the starved perch were in more unfavorable nutritional conditions. In the case of (n-3) fatty acids, starved larvae utilized more linolenic acid 18:3(n-3) and less eicosapentaenoic 20:5(n-3) acid and docosahexaenoic 22:6(n-3) acid than fed perch. Starved larvae probably spared 20:5(n-3) and 22:6(n-3) for physiological functions. 相似文献
747.
Lynnath E. Beckley 《African Zoology》2013,48(3):187-192
The larval development of the southern African endemic sparid Spondyliosoma emarginatum is described and illustrated from specimens collected in Algoa Bay and the Swartkops, Sundays and Swartvlei estuaries of the Cape Province. S. emarginatum has demersal eggs. Preflexion larvae are moderately elongate (BD = 18–23% BL) with body depth increasing to 31 % BL in postflexion stages. The head is rounded and the snout blunt but becomes more elongate in postflexion stages. There are short spines on the preoperculum. Flexion occurs at about 6 mm BL and postflexion larvae are characterized by distinct medio-lateral pigmentation. Osteological development is described from a series of cleared and stained specimens. All fins have the adult complement of spines and rays by 12 mm BL. The larvae of S. emarginatum are compared with those of the European S. canthurus and other southern African sparids. 相似文献
748.
薯蓣零余子的原基起源于叶腋表层1~3层细胞。初期,原基细细胞团分化为内外两部分组织:外侧为薄壁组织及紧邻其内的囊状初生加厚分生组织,内侧为薄壁组织。初生加厚分生组织主要向内衍生细胞,它们分化为薄壁组织和散生其中的有限外韧维管束。零余子的外形多样,常呈块状,无节,基部有1~3个不定芽。从零余子原基外起源、幼期与叶芽间存在过渡型、有限外韧维管束和散生中柱等特点分析,表明其形态本质为茎;从零余子的芽为内起源、无顶端分生组织、主要靠初生加厚分生组织增大体积分析,则它又属于一种特殊的变态茎。 相似文献
749.
大眼鳜幼鱼的发育和生长 总被引:3,自引:0,他引:3
2000年4月2005年4月从嘉陵江合川江段收集大眼鳜亲鱼,通过人工催情获得受精卵,经孵化对其胚后发育和仔稚鱼的生长进行了研究.结果表明:大眼鳜仔稚鱼发育可分为卵黄囊期仔鱼、晚期仔鱼、稚鱼期3个阶段;初孵仔鱼全长4.6-5.2 mm,肌节数32-35对;在水温26.5-29.5℃条件下,历时45-50 d完成仔稚鱼外部形态变化和内脏器官建成;仔稚鱼期全长与日龄呈直线增长关系,拟合的回归方程为L=1.235 9T+1.312 1(R2=0.965 3),全长与肛后长的比值介于1.63~2.44之间. 相似文献
750.