首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   34篇
  免费   0篇
  国内免费   14篇
海洋学   35篇
综合类   13篇
  2009年   2篇
  2006年   1篇
  2005年   1篇
  2003年   8篇
  2002年   1篇
  2001年   3篇
  2000年   4篇
  1999年   3篇
  1998年   3篇
  1997年   2篇
  1996年   1篇
  1995年   2篇
  1992年   1篇
  1991年   1篇
  1990年   3篇
  1989年   2篇
  1988年   1篇
  1983年   1篇
  1980年   1篇
  1979年   3篇
  1978年   2篇
  1964年   2篇
排序方式: 共有48条查询结果,搜索用时 15 毫秒
31.
Isopentnyladenosine(i~6Ado) was identified, and trans-zeatin (trans-Z) and trans-zeatin riboside(trans-ZR) were detected by high pressure liquld chrmoatoguphy (HPLC) but not verified withchromatography - mass spectrometry (GC - M S ) analysis of cytokinin from the extracts of green algae (Ulvapertusa (Kjellm), Enteromopha compressa and Monostma sp). This indicated that the green algae mixturecontained cytokinin -like substances.  相似文献   
32.
It had been demonstrated that individual or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monosproes,and that isolated cells develop in different way in liquid and on semi-solid media,The authors observed the ultrastructure of isolated vegetative cells cultured on semi-solid media and compared them with those of monospores and isolated cells cultured in liquid media,The results showed that subcellular struce-tures were quite different among cells in different conditions.In their development,isolated cells on semi-solid media did not show the characteristic subcellular eature of monospore formation ,such as production of fibrous vesicles,Callus-like cells formed on semi-solid media underwent a distinctive modification in cellular organization.They developed characteristic cell inclusions and a special 2-layer cell covering,Golgi bodies,ER ,starch grains,mitochondria,Vaculoes were not commonly found in them.  相似文献   
33.
The light demands of seaweeds is an interesting and rather complex phenomenon because they depend not only on the species but also on their different development stages. Even different parts of the same plant sometimes have different light demands. Light control is an important procedure at large scale Lamnaria nursery stations in China. Technicians and scientists have different viewpoints on the best method to regulate light. A culture study on Lamnaria japonica starting from zoospores to several centimeter sporophytes to find the optimal and critical irradiance ranges for juvenile Laminaria at different development stages added more knowledge on this aspect. Experiment results show gametophytes can not tolerate irradiance of more than 150uEm-2s-1 while sporophytes can tolerate more than 519 uEm-2s-1. This big difference starts from the very early stage of 1-to 2-celled sporophytes. The biological basis and mechanism of this phenomenon need further research.  相似文献   
34.
坛紫菜北移研究   总被引:1,自引:2,他引:1  
于1985—1988年在青岛进行坛紫菜丝状体培养和叶状体栽培的北移研究。试验结果表明:在自然光温下,3月下旬采果孢子苗,投放密度为200个/cm~2。在丝状体培养期间,利用扩大育苗室的照光面积提高室温,池面加盖聚乙烯薄膜保温,使培苗池水温能达到25—28℃,以满足丝状体各个生长发育阶段要求的温度;利用减光、缩光方法促进丝状体发育。在8月初丝状体大量放散壳孢子,采壳孢子苗的适宜季节是8月上旬—9月中旬,这时采苗可以充分利用北方海区的水温条件,使叶状体能正常生长发育。35天后可采收第一水紫菜。  相似文献   
35.
形成条斑紫菜离体组织再生苗的几种方式   总被引:2,自引:0,他引:2  
紫菜属的不少种类的叶状体通过形成单孢子直接产生叶状体苗,也可以以其他方式直接成苗、一些报道表明,由紫菜叶状体营养细胞直接成苗在不少种类中存在。尤其是离体营养组织块,与离体细胞或原生质体相比,容易获得而且出苗量大,在生产上有潜在的利用价值。作者以条斑紫菜为材料开展的研究取得了以下结果。1材料与方法样品1~6号为中国科学院实验海洋生物学开放研究室海藻种质种苗组保种并在1997年9月育成的6个品系的苗网,在大连旅星海珍品公司海区养成后,11月30日自栽培网上采下,7号样品取自江苏海头养殖海区紫菜网。8…  相似文献   
36.
江蓠属海藻龙须菜的基础研究与大规模栽培   总被引:6,自引:0,他引:6  
江蓠属的龙须菜是1种重要的产琼胶海藻。从2000年在广东汕头南澳岛栽培成功以来,迅速在福建、浙江、山东和辽宁沿海得到发展,成为继海带、紫菜和裙带菜之后又一个新兴的海藻栽培产业群。本文综述了龙须菜遗传学研究成果及龙须菜栽培产业建立和发展的关键因素,包括龙须菜南移栽培,981龙须菜良种培育的技术要点。  相似文献   
37.
INTRODUCTIONThesinglecellsandprotoplastsofPorphyragametophytebladescoulddevelopintoplantletsdi rectlyorintocallus likecells (ZhaoandZhang ,1 981 ;Polne Fulleretal.,1 984 ;Chen ,1 989;WangandYan ,1 990 ;Galletal.,1 993;Chen ,1 997;MeiandFei,2 0 0 1 ) ,andtheirgrowthanddevelopmentunder…  相似文献   
38.
目前我国人工栽培江蓠分为两种主要方式:一是在半咸淡水塘中地播栽培细基江蓠繁枝变种,种苗容易解决,栽培方法简单,产量较高,但琼胶含量低;另一种是在浅滩上用浮筏式夹苗栽培真江蓠、细基江蓠、龙须菜等,培养种苗较麻烦,且产量较低,成本也较高,但琼胶含量高,质量也较好。为取两者的优点,我们把细基江蓠繁枝变种和细基江篱进行杂交,得出了杂交种。实验室培养结果表明,杂交种的琼胶含量介于两者之间,能在半咸淡水中正常生长。初步认为是一个适合于半咸淡水塘中栽培的优良品种,很有发展前途。  相似文献   
39.
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was ...  相似文献   
40.
It had been demonstrated that individual cells or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monospores, and that isolated cells develop in different way in liquid and on semi solid media. The authors observed the ultrastructure of isolated vegetative cells cultured on semi solid media and compared them with those of monospores and isolated cells cultured in liquid media. The results showed that subcellular structures were quite different among cells in different conditions. In their development, isolated cells on semi solid media did not show the characteristic subcellular feature of monospore formation, such as production of fibrous vesicles. Callus like cells formed on semi solid media underwent a distinctive modification in cellular organization. They developed characteristic cell inclusions and a special 2 layer cell covering. Golgi bodies, ER, starch grains, mitochondria. Vacuoles were not commonly found in them.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号