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1.
黄嘴白鹭的繁殖生物学   总被引:7,自引:0,他引:7  
尹祚华  雷富民 《动物学报》2002,48(6):824-827
The Chinese egret is a globally endangered species. This paper describes the breeding behavior of the Chinese egret (Egretta eulophotes) on Xingrentuo Islet, Changhai County, Liaoning Province between April and August 2001. 150 breeding pairs were found at this site, and 60 more pairs were found on nearby Yuanbaotuo Islet, the largest breeding colony in China. Chinese egret arrived at the islet from mid April and departed from late August. Their nests were built in the branches of low trees and fleabanes. 2~6 light greenish blue eggs were layed in each clutch. 40 eggs averaged 45 56(±2 05)mm×33 57(±0 74)mm in size,and 26 46±1 88)g in weight. The hatching period was 21~23 days.  相似文献   

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Mature eggs (at metaphase II stage) produce a series of Ca^2 oscillation at fertilization.To define whether the fertilization-induced Ca^2 oscillation is restrict to the metaphase II eggs and cell cycle dependent,mouse oocytes at prophase I (arrested at germinal vesicle stage),metaphase I,metaphase II,as well as the pronuclear embryos at interphase of the first mitotic division derived from fertilization of parthenogenetic activation were inseminated after removal of zona pellucida,The results show that the fertilization-induced Ca^2 oscillation is not specific to metaphase II eggs.This is supported by the fact that immature oocytes generated the Ca^2 oscillations at fertilization regardless of their nuclear progression from prophase I to metaphase I (in vitro matured) stage.More interestingly,it was first found that pronuclear embryos at interphase derived from parthenogenetic activation showed Ca^2 oscillations in response to fertilization while the zygotes at interphase did not after reinsemination or intracytoplasmic injection of sperm extracts which induce Ca^2 oscillations in MII eggs.This suggests that the ability of oocytes to generate Ca^2 oscillation in response to sperm penetration is not regulated in a cell cycle dependent manner but dependent on the cytoplasmic maturation.  相似文献   

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A comparison of the cDNA sequences (1 056 bp) of Bombyx mori DnaJ 5 homolog with B. mori genome revealed that unlike in other Hsps, it has an intron of 234 bp. The DnaJ 5 homolog contains 351 amino acids, of which 70 contain the conserved DnaJ domain at the N-terminal end. This homolog orB. mori has all desirable functional domains similar to other insects, and the 13 different DnaJ homologs identified in B. mori genome were distributed on different chromosomes. The expressed sequence tag database analysis of Hsp40 gene expression revealed higher expression in wing disc followed by diapause-induced eggs. Microarray analysis revealed higher expression of DnaJ 5 homolog at 18th h after oviposition in diapause-induced eggs. Further validation of DnaJ 5 expression through qPCR in diapause-induced and nondiapause eggs at different time intervals revealed higher expression in diapause eggs at 18 and 24 h after oviposition, which coincided with the expression of Hsp70 as the Hsp 40 is its co-chaperone. This study thus provides an outline of the genome organization of lisp40 gene, and its role in egg diapause induction in B. mori.  相似文献   

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The genus Buergenerula in driftwoods and culms of Spartina alterniflora in intertidal zone is newly recorded from China seas. Taxonomy and morphology of Buergenerula spartinae and the comparison between the species and similar species were discussed in this paper. The specimens were deposited in Mycology Herbarium at Qingdao Agricultural University (MHQAU).  相似文献   

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Nemopoda nitidula (Fallén) and N. mamaevi Ozerov were redescribed and found to be new record species of Sepsidae from China. The specimens were deposited in the Institute of Applied Entomology of Yangzhou University.  相似文献   

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我国婴幼儿中存在不同基因型杯状病毒的感染   总被引:23,自引:3,他引:20  
陈冬梅  张又  钱渊 《病毒学报》2001,17(3):265-269
Human caliciviruses were detected from stool specimens collected from infants with diarrhea from Beijing and Anhui Province by using RT PCR PCR products with molecular weight around 330 were obtained by using the primer pair of 289/290,which is proved to be able to amplify both Norwalk like and Sapporo like human caliciviruses The PCR products amplified from specimens collected in Beijing(CR480) and Anhui(A141) were cloned into the T A cloning vector pUCm T and sequenced The cDNA fragment amplified from CR480 is 319bp in length,which is consistent with the molecular weight of the cDNA fragment amplified from Norwalk like viruses with the primer pair 289/290,whereas the cDNA fragment amplified from A141 is 331 bp in length,which is the size of the cDNA fragment from Sapporo like viruses The sequence analysis revealed that the cDNA from CR480(the stool specimen collected in Beijing) shared higher nucleotide and amino acid identities with selected Norwalk like viruses (from 60% to 97% and 62% to 99%,respectively)than with selected Sapporo like viruses(less than 58%),having the highest identity with Takl 1999 jp and ARG320,which belong to genotype Ⅱ of Norwalk like viruses The sequence of the cDNA from A141 (collected form Anhui Province) shared higher nucleotide and amino acid identities with selected Sapporo like viruses(from 68% to 92% and 75% to 96%,respectively) than with selected Norwalk like viruses(less than 52%) It suggests that both Norwalk like and Sapporo like human caliciviruses are circulating in China and cause diarrhea in infants and young childeren  相似文献   

8.
Embryonic and genetic manipulation in fish   总被引:16,自引:2,他引:14  
Zhu ZY  Sun YH 《Cell research》2000,10(1):17-27
Fishes,the biggest and most diverse community in vertebrates are good experimental models for studies of cell and developmental biology by many favorable characteristics.Nuclear transplantation in fish has been thoroughly studied in China since 1960s.Fish nuclei of embryonic cells from different genera were transplanted into enucleated eggs generating nucleo-cytoplasmic hybrids of adults.Most importantly,nuclei of cultured goldfish kidney cells had been reprogrammed in enucleated eggs to support embryogenesis and ontogenesis of a fertile fish.This was the first case of cloned fish with somatic cells.Based on the technique of microinjection,recombinant MThGH gene has been transferred into fish eggs and the firsh batch of transgenic fish were produced in 1984.The behavior of foreign gene was characterized and the onsed of the foreign gene replication occurred between the blastula to gastrula stages and random integration mainly occurred at later stages of embryogenesis.This eventually led to the transgenic mosaicism.The MThGH-transferred common carp enhanced growth rate by 2-4 times in the founder juveniles and doubled the body weight in the adults.The transgenic common carp were more efficient in utilizing dietary protein than the controls.An “all-fish” gene construct CAgcGH has been made by splicing the common carp β-actin gene (CA) promoter onto the grass carp growth hormone gene (grGH) coding sequence.The CAgcGH-transferred Yellow River Carp have also shown significantly fast-growth trait.Combination of techniques of fish cell culture,gene transformation with cultured cells and nuclear transplantation should be able to generate homogeneous strain of valuable transgenic fish to fulfil human requirement in 21^st century.  相似文献   

9.
Chen  T. C. 《古生物学报》1958,(2):236-274
The specimens described in this paper were collected in the spring of 1955 by the writer andher friends from the Lower Permian Chihsia limestone at Kwanshan, Lungtan, about 20 kmsoutheast of Nanking. The ostracods described and illustrated here comprise 37 species in 11genera, of which 29 species are new. The majority of the specimens were found in the middlepart (ca. 138 m. in thickness) of the Chihsia formation. The specimens are more or less  相似文献   

10.
ON THE PERMIAN DIAPHANOPTERODEA AND HOMOPTERA OF INNER MONGOLIA, CHINA   总被引:1,自引:0,他引:1  
This is the first paper on Palaeozoic Diaphanopterodea and Homoptera of China.Both orders were found in the slaty shale of the Permian stratum of Wuasukou, InnerMongolia Autonomus Region. Totally 3 specimens were colleeted and identified, ofwhich, 2 specimens (obverse and reverse parts of a single wing) of the order Diaphano-  相似文献   

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Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.
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正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various  相似文献   

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<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV  相似文献   

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正Dear Editor,Mink circovirus (MiCV), which is clustered in the genus Circovirus of the family Circoviridae, was first described in minks from farms in Dalian, China in 2013 (Lian et al.2014). The complete single-stranded circular genome of the virus is 1,753 nucleotides long and contains two major open reading frames (ORFs), designated ORF1 (Rep gene)and ORF2 (Cap gene)(Lian et al. 2014; Ge et al. 2018).Sequence analysis has shown that MiCV is most closely  相似文献   

19.
Cyclophilin A (CypA) is a peptidyl-prolyl cis/trans isomerase that interacts with the matrix protein (M1) of influenza A virus (IAV) and restricts virus replication by regulating the ubiquitin–proteasome-mediated degradation of M1. However,the mechanism by which CypA regulates M1 ubiquitination remains unknown. In this study, we reported that E3 ubiquitin ligase AIP4 promoted K48-linked ubiquitination of M1 at K102 and K104, and accelerated ubiquitin–proteasome-mediated degradation of M1. The recombinant IAV with mutant M1 (K102 R/K104 R) could not be rescued, suggesting that the ubiquitination of M1 at K102/K104 was essential for IAV replication. Furthermore, CypA inhibited AIP4-mediated M1 ubiquitination by impairing the interaction between AIP4 and M1. More importantly, both the mutations of M1 (K102 R/K104 R) and CypA inhibited the nuclear export of M1, indicating that CypA regulates the cellular localization of M1 via inhibition of AIP4-mediated M1 ubiquitination at K102 and K104, which results in the reduced replication of IAV.Collectively, our findings reveal a novel ubiquitination-based mechanism by which CypA regulates the replication of IAV.  相似文献   

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