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1.
刘建国 《中国海洋湖沼学报》1999,(3)
INTRODUCTIONMicroalgalbiotechnologyhasattractedmoreandmoretheinterestofscientistsandpeopleex ploitingitscommercialpossibilitiesasitisthebiotechnologythatcanmatchbacterialbiotechnologyinthecomingcenturyintheaspectofeconomicreturnoninvestment.Dunaliellasalinaisoneofthemostdetailedlystudiedunicellulargreenalgae,hassomeuniquescientificvalues,andgreatestpotentialformasscultureasafoodsource ,andisrichestalgalsourceofglycerolandβ carotene(Borowitaka,1 988;Ginzburg,1 987) .Optimizingperformanceo… 相似文献
2.
Nephroselmis gaoae sp. nov. is described on the basis of light and electron microscope observations of cultured material originally collected
and isolated from seawater of Jiaozhou Bay, Qingdao, China. The periplasts on the cell body and flagella are covered by five
types of scales, two types on the flagella and three on the body. Among these, the morphology and the number of spines of
large stellate body scales differ remarkably from those of previously described species ofNephroselmis. Apart from these, the unusual fine structure of the eyespot (stigma) is very characteristic. As in the other species ofNephroselmis, the eyespot lies immediately under the two-membraned chloroplast envelope; unlike the others, however, it is not composed
of a number of osmiophilic globules, but consists of about 14 curved rod-shaped osmiophilic bodies arranged loosely and randomly.
This feature distinguishes the present new species not only from the other species ofNephroselmis but also from the other motile algal species, the eyespots structure of which had been previously described.
Contribution No. 2316 from the Institute of Oceanology, Chinese Academy of Sciences.
This paper was presented at the XIVth International Seaweed Symposium held in Brittany, France, 1992. 相似文献
3.
A bloom of the dinoflagellate Scrippsiella trochoidea was detected for the first time in inner Tolo Harbor, Hong Kong in 2 000. Water samples were collected at eight stations
along a transect passing through a red tide patch for microscopic analysis of phytoplankton composition and high-performance
liquid chromatography (HPLC) analysis of phytoplankton pigments. During the bloom, the density of dinoflagellates was 1.1×106 cells L−1 within the patch and 8.6×105 cells L−1 outside the patch where the phytoplankton community was dominated by diatoms. After the bloom the S. trochoidea began to decrease in density and was replaced by diatoms as the dominating bloom-causing organisms at all stations, and the
density of dinoflagellates at most stations was less than 1.0 × 106 cells L−1. The status of S. trochoidea as the causative species of the bloom was indicated by the presence of peridinin, the marker pigment for dinoflagellates.
The shift from dinoflagellates to diatoms was marked by the decline of peridinin and the prevalence of fucoxanthin. Phytoplankton
pigment markers also revealed the presence of other minor phytoplankton assemblages such as cryptomonads and blue-green algal. 相似文献
4.
Tingjun Fan Miaomiao Yu Lingling Yang Zhenping Shi Wenjie Sun Rishan Cong Xiuxia Yang Guojian Jiang 《中国海洋大学学报(英文版)》2009,8(3):222-228
To investigate the stimulating effects of immunostimulants on the autogenous immunocompetence of crabs and the possible mechanisms
involved, the immunostimulating effects of β-1,3-glucan, lipopolysaccharide (LPS), inactivated Vibrio harveyi and Vibrio anguillarum on phenoloxidase (PO) and hemocytes of Charybdis japonica were investigated in this study. It was found that the yields and the enzymatic activities of purified PO in C. japonica increased significantly after the crabs were treated with immunostimulants, while the unit enzymatic activities remained
almost the same. After treatment with β-1,3-glucan and LPS, the amount of rough endoplasmic reticulum (RER) and the number
of mitochondria in both semigranular cells and granular cells increased greatly, and the number of cytoplasmic granules decreased
but with enlarged volume. However, the corresponding characteristics of hyaline cells remained almost the same. On the other
hand, the number of granules in semigranular cells decreased greatly, and the number of mitochondria of hyaline cells increased
greatly, after treatment with inactivated vibrios. It may be concluded that the effect of polysaccharide immunostimulants
on the innate immune system of C. japonica is different from that of inactivated vibrio immunostimulants. The immunity-enhancing mechanism of polysaccharides in crab
autogenous immunocompetence is probably accomplished by the increased yields of PO and total PO activities, while that of
inactivated vibrios is probably accomplished by the partially increased yields of PO and total PO activities as well as the
significantly improved phagocytotic abilities of semigranular cells and hyaline cells. 相似文献
5.
The gastric shield and underlying stomach epithelium of Chlymas ffarreri were examined at the light and ultrastructural levels.The results showed that the gastric shield consisted of two different size lobes joined together by a narrow middle piece,the thicker lobe was shaped like a funnel,but unclosed at the lateral side;the other lobe was irregularly triangular-shaped.The transverse section of the thicker lobe was obviously laminated and gradually decreased in thickness from the peak to the margins of the shield.The underlying epithelium bore numerous about 3μm diameter spherical processes formed by the apical plasmalemma of the epithelial cells becoming blunt pseudopodia.Microvilli and some interspersed cilia were present in the areas among the spherical processes regions where only microvilli existed.Rough endoplasmic reticulum,Golgi apparatus,different-sized electron-dense secretory granules and electron-lucent vacuoles as well las abundant mitochondria were present in the underlying epithelial cells.Fused droplets of the secretion from the underlying epithelial cells formed the gastric shield. 相似文献
6.
Heat shocks effectively produced triploids inPenaeus chinensis. Fertilized eggs heat shocked (28–32°C) for 8 to 16 minutes, starting from 8 to 20 minutes after spawning, resulted in triploidy
induction rates of 39%–75%. Several triploid populations were cultured to 10 cm. In a triploid population, two kinds of ovaries
were observed. Histological examination showed apparent differences between these two kinds of ovaries, whereas among male
shrimp, there were no such differences.
Contribution No. 3465 from the Institute of Oceanology. Chinese Academy of Sciences.
The study was supported by the International Foundation for Science, Asian Fisheries Society and Chinese Climbing Project
PDB 6–2, and Chinese National 863 Project (No. 863-819-01-05). 相似文献
7.
STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFI—EYED FLOUNDER, PARALICHTHYS OLIVACEUS （T. et S. ） 总被引：1，自引：0，他引：1
The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student‘s t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied. 相似文献
8.
Vibrio harveyi cells (dose—<103 cells mL−1) and extracellular products (ECP; >25 μmg mL−1 of total protein concentration) destroyed haematopoietic cultures of Nephrops norvegicus within 24 h of exposure. Cytopathic effects (CPE) started after 4h of exposure to the bacterial cells, with some granularity
in the cytoplasm, mostly in cells in the outer periphery of the explant growth. At the end of the infection, a considerable
number of nuclei remained attached to the substrate, apparently unaffected. Following exposure to ECP, initial deterioration
was observed at 2 h with the presence of granularity in the cytoplasm of<20% cells, and few cells displayed small vacuoles
around the nuclei. Parallel results were obtained using whole animal experiments, with V. harveyi cells being lethal to nephrops within 24 h. 相似文献
9.
Zhang Guo-fan Chang Ya-qing Song Jian Ding Jun Shen Jin-kai Wang Yong-ping 《中国海洋湖沼学报》1998,16(3):249-255
Zygotes of Pacific oyster (Crassostrea gigas) were treated for triploid induction with caffeine (10 mmol/L, 15mmol/L and 20mmol/L) in combination with thermal shocks
(at 40 minute post-fertilization) lasting for 5 and 10 minutes. The highest yield of triploids, 41.5%, was obtained from the
treatment with 20 mmol/L caffeine at 34°C lasting 10 minutes. The triploid levels were less than 30.0% in other treatments.
Triploid induction was more effective in treatment with 15–20 mmol/L caffeine at 34–38 °C than with lower concentrations of
caffeine at temperatures below 32 °C. Our results suggest that triploid induction with caffeine in combination with thermal
shocks is less efficient than some other methods reported previously. 相似文献
10.
Most studies on Haematococcus pluvialis have been focused on cell growth and astaxanthin accumulation;far less attention has been paid to cell cycles and proliferation patterns.The purpose of this study was to clarify cell cycles and proliferation patterns in H.pluvialis microscopically using a camera and video recorder system.The complicated life history of H.pluvial i s can be divided into two stages:the motile stage and the non-motile stage.All the cells can be classifi ed into forms as follows:motile cell,nonmotile cell,zoospore and aplanospore.The main cell proliferation,both in the motile phase and non-motile phase in H.pluvialis,is by asexual reproduction.Under normal growth conditions,a motile cell usually produces two,sometimes four,and exceptionally eight zoospores.Under unfavorable conditions,the motile cell loses its fl agella and transforms into a non-motile cell,and the non-motile cell usually produces 2,4 or 8 aplanospores,and occasionally 20–32 aplanospores,which further develop into non-motile cells.Under suitable conditions,the non-motile cell is also able to release zoospores.The larger non-motile cells produce more than 16 zoospores,and the smaller ones produce 4 or 8 zoospores.Vegetative reproduction is by direct cell division in the motile phase and by occasional cell budding in the non-motile phase.There is,as yet,no convincing direct evidence for sexual reproduction. 相似文献
11.
The early stages and capsulogenetic stages of sporogenesis ofMyxobolus kwangsiensis were studied in detail by electron microscopy.M. kwangsiensis is an intracellular myxosporean infecting the epithelial cells of kidney tubules of young daceLabeo rohita. TheM. kwangsiensis sporogensis presents the typical features of myxosporea. The initial stages are multinucleate primary cells, with one primary
cell typically enclosing one secondary cell. The secondary cells are formed directly by cytokinesis inside the primary cells.
The primary cell participates in the formation of the secondary cell nucleus. The nuclear division of primary cell is asynchronous
by amitosis. The parasitic organisms may degenerate inside the epithelial cells at any stage. The modes of sporoblast formation,
the typical features of myxosporea and the cause of its degradation are discussed.
This research was supported by the NSFC. (No. 39070675) 相似文献
12.
There are many reports that cells (protoplasts) separated from the thallus ofPorphyra by enzyme can develop to normal leafy thalli in the same way as monospores. But there are few investigations on the subcellular
structure of the isolated vegetative cell for comparison with the subcellular structure of monospores. To clarify whether
the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores
undergo in their formation and germination, we observed their ultrastructure, compared them with those of the monospore and
found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore
formation, such as production of small and large fibrous vesicles, but was accompanied by vacuolation and starch mobilization
like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells.
Contribution No. 3875 from the Institute of Oceanology, Chinese Academy of Sciences.
Project 39770593 supported by NSFC; Project 96-C01-05-01 of the 9th Five-Year Plan supported by Science and Technology Commision
of China. 相似文献
13.
AmpLifications with 300 10-base primers under predetermined optimal reaction yielded 2762 reproducible amplified fragments ranging from 200 to 3000 bp. Genetic distances among five species of Takifugu and Lagocephalus spadiceus as outgreup were calculated based on the presence/absence of the amplified fragments. Topological phylogenie trees of the 5 species of Takgfugu and the outgroup were gen-erated by Parsimony and Neighbor-Joining analysis based on RAPD data set. The genetic distance between T. rubripes and T. pseudommus was almost the same as that between individuals within each species, but was much smaller than that among T. rubripes, T. pseudommus and the other species. The molecu-lar data from RAPD analysis convincingly showed that T. rubripes and T. pseudommus should be the same species. 相似文献
14.
Two new species of the genus Tinocladia Kylin, T. gracilis sp. nov. and T. microsporangii sp. nov,, are described. T. gracilis is characterized by its slender frond, variable size, infrequently branched medullary filaments, and short assimilating filaments with 2 - 7 cells. T. microsporangii is characterized by its medullary cells which are slightly larger than sub-cortical ones; narrow sub-cortical layer, usually consisting of 4- 6 cells and very small unilocular sporangia. The holotypes are deposited at the Herbarium of the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China. 相似文献
15.
Structure and function of the digestive system of a bivalve mollusc, Solen grandis, were studied using light microscopy and histochemical methods. The wall of digestive tube consists of four layers: the mucosal
epithelium, connective tissue, muscular and fibrosa or serosa (only in the portion of rectum) from the inner to the outer.
The ciliated columnar epithelial cells, dispersed by cup-shaped mucous cells, rest on a thin base membrane. There are abundant
blood spaces in connective tissue layer. The digestive diverticula are composed of multi-branched duct and digestive tubules.
The digestive tubules are lined with digestive and basophilic secretory cells, and surrounded by a layer of smooth muscle
fibers and connective tissues. Activities of acid and alkaline phosphatases, esterase and lipase are detected in the digestive
cells, and the epithelia of stomach and intestine, suggesting that these cells are capable of intracellular digesting of food
materials and absorbing. Besides, acid phosphatase and esterase activities are present in the posterior portion of esophagus.
Phagocytes are abundant in blood spaces and the lumens of stomach and intestine, containing brown granules derived from the
engulfed food materials. The present work indicates that phagocytes play important roles in ingestion and digestion of food
materials, which is supported as well by the activities of acid phosphatase, esterase and lipase detected in blood spaces. 相似文献
16.
Histological characteristics of gametogenesis of two kinds of scallops, gonochoric Chinese scallop, Chlamys farreri and hermaphroditic bay scallop, Argopecten irradians were investigated in this study. Spermatogenesis in C. farreri has different developmental stages: spermatogonia, primary spermatocyte, second spermatocyte, spermatid and spermatozoon. A large number of same developmental stage spermatic cells converge at a definite area of the testis. Premeiotic, previtellogenic and vitellogenic oocytes can be found during oogenesis in C. farreri, where oocyte distribution is obviously irregular. The A. irradians gonad consists of two different parts in one individual: one part functions as testis, the other as ovary. Between these two parts is a special appearance area, where a large number of spermatic cells are bound with two layers of acellular substance with many oocytes in it. 相似文献
17.
The interspecific interactions between the rotifer Brachionus plicatilis and two harmful algal blooms (HAB) species were investigated experimentally by single culture method. B. plicatilis population and the growth of the two algae were compared at different algal cell densities. The results demonstrated that
the B. plicatilis obtained sufficient nutrition from Prorocentrum donghaiense to support net population increase. With exposure to 2.5×104 cells mL−1 of P. donghaiense, the number of B. plicatilis increased faster than it did when exposed to other four algal densities (5, 10, 15 and 20 ×104 cells mL−1), and the increase rate of B. plicatilis population (r) at this algal density was 0.104 ± 0.015 rd−1. Cell densities of P. donghaiense decreased due to the grazing of B. plicatilis. In contrast, Heterosigma akashiwo had an adverse effect on B. plicatilis population and its growth was largely unaffected by rotifer grazing. In this case, B. plicatilis population decreased and H. akashiwo grew at a rate similar to that of the control. 相似文献
18.
Observation of female gamete (Carpogonia) germination of Porphyra yezoensis and P. oligospermatangia
Several papers have reported that part or whole leafy thallus seemingly consisting of zygotospores can give rise to both blades
and conchocelis in the same culture ofPorphyra. Study on samples of wild and cultivatedPorphyra yezoensis andP. oligospermatangia were conducted to clarify the origination of the young blades in the culture. It is confirmed that single cells on the blade
of both species, which normally intermixed with zygotospores, germinated into young blades. TEM and SEM observation has shown
that the single cells ofPorphyra yezoensis had typical features of female gamete (carpogonia) but archeospore. Therefore, the female gametes are responsible in developing
leafy thalli.
This project was sponsored by the NSFC (No. C-0205-05-39770593) 相似文献
19.
The toxicity of seven major HAB (harmful algal bloom) species/strains, Prorocentrum donghaiense, Phaeocystis globosa, Prorocentrum micans, Alexandrium tamarense (AT-6, non-PSP producer), Alexandrium lusitanicum, Alexandrum tamarense (ATHK) and Heterosigma akashiwo were studied against rotifer Brachionus plicatilis under laboratory conditions. The results show that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6), or A. lusitanicum could maintain the individual survival and reproduction, as well as the population increase of the rotifer, but the individual
reproduction would decrease when exposed to these five algae at higher densities for nine days; H. akashiwo could decrease the individual survival and reproduction, as well as population increase of the rotifer, which is similar
to that of the starvation group, indicating that starvation might be its one lethal factor except for the algal toxins; A. tamarense (ATHK) has strong lethal effect on the rotifer with 48h LC50 at 800 cells/mL. The experiment on ingestion ability indicated by gut pigment change shows that P. donghaiense, P. globosa, P. micans, A. tamarense (AT-6) and A. lusitanicum can be taken by the rotifers as food, but A. tamarense (ATHK) or H. akashiwo can be ingested by the rotifers. The results indicate that all the indexes of individual survival and reproduction, population
increase, gut pigment change of the rotifers are good and convenient to be used to reflect the toxicities of HAB species.
Therefore, rotifer is suggested as one of the toxicity testing organisms in detecting the toxicity of harmful algae.
Supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-208), National Natural Science
Foundation of China (No. 40821004, U0733006) and National Basic Research Program of China (973 Program, No. 2001CB409700) 相似文献