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21.
文昌鱼鳃组织原代培养   总被引:1,自引:0,他引:1  
采用组织块培养法培养文昌鱼(Branchiostoma belcheri japonicum)鳃细胞,使用L15,M199,Eargle'sMEM为基础培养基,加入一定量的NaCl及5%,10%,20%等不同体积分数的牛血清.经条件优化后得到最适合的培养条件为2L15+20%FBS+0.45%NaCl,在26~28℃条件下培养,组织块贴壁后12 h内就有至少4类上皮样细胞从中迁移出来,这些细胞在前3天迅速增殖,到第6天基本上达到平稳期,往后细胞开始凋亡,最长可以存活近两个星期.鳃细胞的原代培养为文昌鱼细胞体外培养的深入研究提供了实验依据.  相似文献   
22.
甲壳动物渗透压调节是其生命过程中非常重要的生理活动。调节过程主要由鳃上皮来完成。综述了鳃上皮的结构与功能以及它在调节渗透压时的生化特点、生理机制和它在盐度变化时 的形态结构变化、生理生化过程。  相似文献   
23.
报道采自山东沿海贝类鳃表及外套腔中寄生 /共栖的 3种吻毛类纤毛虫 :原生钩毛虫(Ancistrocoma primigenius)、派氏钩毛虫 (Ancistrocoma pelseneeri)及威海下毛虫 (Hypocomidesweihaiensis)。作者依据活体观察、蛋白银和银浸法染色对其活体形态学、纤毛图式及银线系进行了综合描述。该研究系钩毛虫属纤毛虫在我国的首次报道。  相似文献   
24.
This study provided evidence that Zostera noltii presence affects macrofauna community structure independently from median sediment grain-size and that the notion of ecosystem health is rather subjective: in the present case, we recorded “good health” in terms of seagrass development, “no impact” in terms of macrobenthic biotic indices and “negative effect” for a given key-population. The occurrence and development of a Z. noltii seagrass bed was surveyed at Banc d’Arguin, Arcachon Bay (France), to estimate the modification of the macrozoobenthic community and of the dynamics of a key-population for the local ecosystem, – the cockle Cerastoderma edule. Even though median grain-size of the sediment decreased only at the very end of the survey, i.e. when seagrass totally invaded the area, most of the macrofauna community characteristics (such as abundance and biomass) increased as soon as Z. noltii patches appeared. The structure of the macrofauna community also immediately diverged between sand and seagrass habitats, without however modifying the tested biotic indices (BENTIX, BOPA, AMBI). The health of the cockle population (growth, abundance, recruitment) was impacted by seagrass development. Related parasite communities slowly diverged between habitats, with more parasites in the cockles from seagrass areas. However, the number of parasites per cockle was always insufficient to alter cockle fitness.  相似文献   
25.
Crossbreeding is an effective approach to manage the genetic decline in aquaculture.One-way hybrids of Crassostrea sikamea(♀)and Crassostrea gigas(♂)have advantages in growth traits and adaptation to high temperature.Here,we used high-throughput sequencing to analyze the molecular processes in the hybrids under and after thermal stress.The hybrids were cultured in the seawater with an increasing temperature from 25℃to 40℃during 10 hours,which is regarded as the thermal stress stage.Then the temperature decreased from 40℃to 25℃within 2 h,which is regarded as the recovery stage.In this study,1293 significant diffe-rentially expressed genes(DEGs)were obtained under thermal stress,of which 576 were upregulated and 717 were downregulated,and 740 significant differentially expressed genes(DEGs)were obtained in the recovery stage,of which the number of upregulated and downregulated genes was 409 and 331,respectively.The antigen processing and presentation,NOD-like,and NF-kappa B path-ways were significantly enriched during the thermal stress stage.The MAPK and PPAR signaling pathways were significantly enrich-ed during the recovery stage.The HSP70,HSP90,and CANX genes were strongly and rapidly upregulated in the control/thermal stress groups but were slightly less upregulated in the thermal stress/recovery group.These results indicate that the innate immune system or nonspecific immunity was deployed to protect interior tissues from thermal stress.In addition,85%of the mutual DEGs were involved in bidirectional regulation(up/down or down/up)when the oysters were removed from the thermal stress to recover.This study provides preliminary insight into the molecular response of C.sikamea(♀)and C.gigas(♂)hybrids to thermal stress and provides a basis for future studies on temperature-adaptation and the possible expansion of hybrid breeding.  相似文献   
26.
中国对虾鳃的超微结构研究   总被引:1,自引:0,他引:1  
本文报道中国对虾Penaeuschinensis鳃的超微结构,结果表明,虾鳃具有三级结构,鳃瓣小叶是鳃的基本呼吸单位,它由鳃膜、呼吸上皮细胞及微血腔组成。文中分别描述了它们的超微结构特征,可供对虾组织细胞病理学诊断作对照参考。  相似文献   
27.
Abstract. The pyramidellid snail, Boonea (= Odostomia) impressa (SAY), is an important ectoparasite of the oyster, Crassostrea virginica (G melin ). The small-scale spatial distribution of snails was examined in 11 oyster populations in the Copano Bay - Aransas Bay area of the Texas coast. Snails were contagiously distributed (s2/>1) and positively spatially autocorrelated. Patchiness was better developed and patches were larger on enclosed reefs than on more exposed open-bay reefs, probably because higher wave energy and increased distance between oyster clumps limited clump-to-clump movement by snails on open-bay reefs. Small snails were consistently distributed differently from large snails because small snails were less host specific. As the snails grow, a narrowing of host preference results in a substantial change in spatial distribution. Snails were consistently more contagiously distributed than their hosts; however, snail distribution was not host-density dependent. Factors determining the spatial distribution of the host had surprisingly little effect on the distribution of snails. Snail aggregates apparently form randomly by chance meetings of a few snails and then grow by attraction of additional snails. Consequently, snail behavior, which determines the size and length of time a patch retains its integrity, and the age distribution of the snail population may be the two most important factors, besides population size, determining the impact of B. impressa on oyster populations.  相似文献   
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29.
短盖巨脂鲤鳃、伪鳃和鳔胚后发育学研究   总被引:1,自引:0,他引:1  
本文应用切片和显微技术,对短盖巨脂鲤鳃、伪鳃和鳔的胚后发育的组织形态学进行了研究。短盖巨脂鲤鳃的胚后发育可分为三个阶段:第一阶段(0~1日龄),原基期,鳃原基形成但未分化。第二阶段(2~10日龄),鳃结构发育、分化。第三阶段(11日龄之后),鳃的生长完善期。伪鳃由口腔壁分化出来,胚后发育分为三个阶段:第一阶段(0~2日龄),原基形成期。第二阶段(3~7日龄),发育分化期。第三阶段(8~21日龄),结构完善期。鳔的胚后发育可分成四个阶段:第一阶段(0~1日龄),原基形成期。第二阶段(2~5日龄),结构分化期。第三阶段(6~11日龄),充气期。第四阶段(13天以后),完善与生长期。  相似文献   
30.
珠江水系贺江段近年出现严重危害网箱养殖和江河鱼类资源的大型寄生虫病害.初步鉴定该虫隶属于甲壳纲.等足目.鳃虫科.细角鳃虫属.是国内新发现的淡水鱼类寄生虫。用该虫对草鱼、银鲫、麦鲮进行人工感染.结果表明:该虫具有很强的寄生能力.累积感染率为76.2%~100.0%;对寄生部位具有一定的选择性,以寄生在鳃部的比例(55.6%~72.0%)最大.胸鳍(11.7%~28.8%)次之;对试验鱼有较强的致死性;该虫吸血后体长(L)增长较大.体宽(W)基本不变;从寄主体上主动脱落的虫体,其L/W的增长率(16.32%~18.00%)较大,而一直寄生在寄主身上的虫体.其L/W的增长率则因各自摄食量的不同而存在较大的差异。  相似文献   
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