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991.
Amphioxus, a cephalochordate, is an important model fish for studies in evolution and comparative biology. A successful cell culture from amphioxus tissues in vitro would help understanding some basic issues. To determine the optimal culture conditions for proliferation of amphioxus cells, primary cultures were initiated from buccal cirri, tail, gill, gut and metapleural fold of amphioxus Branchiostoma belcheri tsingtauense. The media tested were L-15, F-12, M 199, MEM, DMEM, PRMI 1640 and LDF, each was supplemented with 20% fetal bovine serum. The optimal conditions include tail tissue cultured in L-15 or F-12 with supplement of 20% FBS and 1.5% NaCl at about 25°C. Supported by Doctoral Initial Fund of Ludong University (No.43304)  相似文献   
992.
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????????????????????????????????????????????????????С????????в???????,?????????????С???????????????????????????????????Tikhonov?????????????????????С??????????????????????????????????????????????Э????????????????????Fredholm???????????????????????????С????????????????????? ???????????????????????й?????????????????????????????  相似文献   
993.
Animal-sediment relationships of two benthic communities (Crustaceans and Polychaetes) were studied around Mandvi coast in the Gulf of Kachchh, Western India. This coast consists of many micro-geomorphic landforms in which benthic communities are inhabited and select their niches and produce endemic biogenic structures. Five intertidal subfacies have been described and four types of grounds are identified, based on substrate consistency. 18 species of crustaceans, 15 species of polychaetes and unsegmented worm nemertea have been identified. Crustacean behavioural activities were observed in dunes, beaches and ridge-runnel in the form of burrowing, pellet making, feeding and crawling traces. Pelleted wall lining burrows of the suspension feeder stomatopodean species of Oratosquilla striata are also abundant in runnels. Motile, deposit feeder polychaetes are abundant on the ridges and are occasionally found on the lower reaches of the beaches, while suspension and filter feeders are found in the runnels. Lagoons consist of mainly grouped funnel branched burrows of Oniphus eremita which is identical to ichnogenus Balanoglossites. Nemertea, which are opportunistic algal grazers, have exploited restricted niches for dwelling-feeding purposes and constructed vertical burrow with pentamerous conical mound. The shore platform consists of cemented, calcareous tubes of filter feeder Serpula along with symbiotic encrusters like Ostrea and barnacles. Ichnocoenoses are discussed and three-dimensional ichno-sedimentologic models are reconstructed for Beach, Ridge, Runnel and Lagoon of the Mandvi intertidal zone.  相似文献   
994.
Zhou  Liqing  Wang  Xuemei  Wu  Biao  Sun  Xiujun  Zhao  Qing  Zhang  Gaowei  Liu  Zhihong  Yang  Aiguo 《中国海洋湖沼学报》2019,37(1):169-175
Journal of Oceanology and Limnology - Blepharipoda liberate Shen is a commercially valuable seafood species that has important ecological significance in Shandong Province, China. Although B....  相似文献   
995.
刘永翊 《天文学进展》1997,15(3):247-253
简要综述了近年来对于星际CH3OH脉泽的观测和研究成果,对CH3OH脉泽的性质从分类,生成区域及分布,辐射特性,运动状况等方面做了介绍,并阐明了理论上对其时变特性,激发机制及河外脉泽的探讨,最后对两种类型的CH3OH脉泽作了对比和讨论。  相似文献   
996.
We summarize the ASCA observations of the two Galactic superluminal sources GRO J1655–40 and GRS 1915+105, focusing on theabsorption line features.The high spectroscopic capability of ASCA enabled us to detectiron-K absorption line features from both objects. This is direct evidence for the presence of highly ionized plasma in a non-spherical configuration around a black hole, and is considered to be a unique signature of superluminal jet systems. The candidate of the line-absorber would be a part of an accretion disk at a distance of 109-11 cm from the central X-ray source.  相似文献   
997.
We present first results from a monitoring campaign of GRS 1915+105 undertaken with the USA X-ray timing experiment on the ARGOS satellite. A variety of behaviour has been observed, ranging from low, steady X-ray emission to rapid quasi-periodic flaring on timescales of approximately 10–120 seconds.  相似文献   
998.
The Ultra-luminous Compact X-ray Sources (ULXs)in nearby spiral galaxies and the Galactic super-luminaljet sources sharethe common spectral characteristic that they haveextremely high disk temperatures which cannot be explainedin the framework of the standard accretion disk modelin the Schwarzschild metric. We have calculated an extreme Kerr disk model to examine if the Kerr disk model can instead explain the observed `too hot' accretion disk spectra.We found that the Kerr disk spectrum becomes significantly hardercompared to the Schwarzschild disk only when the disk is highlyinclined.For super-luminal jet sources, which are known to beinclined systems, the Kerr disk model may thuswork if we choose proper values for the black hole angular momentum. For the ULXs, however, the Kerr disk interpretation will be problematic,as is is highly unlikely that their accretion disks are preferentiallyinclined.  相似文献   
999.
Finite element modeling on a highly conceptualized 2-D model of fluid flow and heat transport is un-dertaken to simulate the paleo-hydrological system as if the Mount Isa deposits were being formed in the Mount Isa basin, Northern Australia, and to evaluate the potential of buoyancy force in driving ba-sin-scale fluid flow for the formation of sedimentary-exhalative (SEDEX) deposits. Our numerical case studies indicate that buoyancy-driven fluid flow is controlled mainly by the fault penetration depth and i...  相似文献   
1000.
The Hadamengou gold deposit is located in the western segment of the northern margin of the North China Craton (NCC). It is hosted by Archean metamorphic rocks of the Wulashan Group. The main ore types include gold-bearing quartz vein type, gold-bearing quartz-potassic feldspar vein type, and gold-bearing altered rock type. Gold mineralization is closely related to K-feldspathization. Hydrogen and oxygen isotope data indicate that ore-forming fluids were dominated by magmatic water mixed with minor meteoric water. Sulfur and lead isotope data indicate that metallogenic materials were mainly supplied by the magmatic and Archean Wulashan Group. The gold mineralization was mainly formed during the Early Indosinian tectonic movement, which drove ore-forming fluids to the favorable depositional environment. The northern margin of the NCC is a prospective area for gold exploration. Gold deposits hosted by or related to alkaline intrusions have become one of the most important mineral exploration targets in northern China.  相似文献   
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