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2003年  第24卷  第2期

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研究论文
To form tetraploid embryos,electric pulses were used to stimulate 2-cell blastomeres of Kunming mice.The pulses included combinations of four strengths (600,800,1000 and 1200 V/cm) and three durations (10,30 and 50 μs).Of the combinations,600 V/cm×50 μs and 1200 V/cm×30 μs produced the fusion rates of 91.6% and 93.0% respectively,and both were higher than the others.On the other hand,the pulses of 600 V/cm×10 μs and 1200 V/cm×50 μs did the rates of 58.9% and 60.2% respectively,being significantly lower than the others.The results showed that a certain pulse strength was necessary to achieve embryo fusion,and the duration was a key factor affecting the embryo fusion and its later development.What observed with a laser confocal microscope implied that the allocation,approach and fusion of nucleus was a spontaneous process in fused embryos.
Data on soil mesofauna in fields of bamboo(as natural soil,NS),paddy rice,tea,orange,cabbage(as cultivated lands,CL) and fallow(as arable,A) were collected in Quzhou region in a period from March to December,2001.Using the community parameters of population density,group richness(GR),diversity index(DI) and evenness,we described the community structure and its seasonal changes,and clustered the Euclidean distances among the soil types.There were 19 groups of mesofauna in this region,and of the groups Acarina and Collembola were dominant,and Diptera,Coleoptera and Hymenoptera were often seen.Based on annual data,there was a difference in the community structure of the mesofauna between NS and CL-A(for NS,GR=13.25±0.25,DI=2.27±0.28;for CL-A,GR=7.55±0.88,DI=1.57±0.15),but no difference among soil types of CL-A.Based on seasonal data on the community structures of the mesofauna in the 6 soil types,the fields of cabbage,tea and orange showed the highest similarity.They then joined with rice field,and fallow,finally with bamboo field.Of the soil types,bamboo field had the highest GR and DI,and could possibly be ranked the best in quality in this region.
The contents of growth hormone (GH) and triiodothyronine (T[3]) in serum,and protein and lipid in white muscles were measured for black seabreams (Sparus macrocephalus) in starvation for 2,5,10,15 and 30 days as treatments.At the same time the measurements were also made for the animals under normal condition as control.Testing for the difference between the treatment and control resulted in:1)the level of serum GH significantly increased after 15-day-starvation,and that of T[3] decresed;2)the content of protein in white muscles decresed after 15-day-starvation,and the reduction of lipid occurred after 2 d and kept the low level to the end;3)the content of lipid in livers increased significantly after 10 d,and that of protein fluctuated irregularly.The increase of serum GH could ehance the translation of body materials into engery,and the reduction of T[3] would reduce the metabolic rate,which could be viewed as physilological responses for the species to adapt the stress of starvation.
Based on the phylogenetic relation and distribution of four grasshopper genera of Catantopidae,Oxya Serville,Caryanda St?l,Sinopodisma Chang and Traulia St?l,ten areas of endemism have been recognized.Using cladistic biogeographical software COMPONENT 2.0 and under assumptions 0 and 1,data processing resulted in following geographical history course of these areas,the vicariance was in time sequence from South Yunnan,to Loess Plateau,to Hainan Island,to East mountains.Although Taiwan Island is vicarianced from mainland of China in the Middle Pleistocene,it had been connected with the mainland for some times in the Quaternary Period,effected by the ice age and it has an unique zoogeographical position.Yungui Plateau,North Yunnan and QinlingBashan Mountains were formed in the same time.The newly areas of endemism were South China and Jiangnan hills.
Lacertid lizards,Eremias brenchleyi were captured from field,and reared artificially.Laid eggs were incubated at 30 ℃ and -12 kPa (humidity).Whole eggs,eggshells,yolks,and embryos were weighed,and energy of certain components was determined at a series of time points.Data on the development of embryos and the transition of material and energy in eggs incubation were processed,resulting in:1)The duration of incubation averaged 35 days,and the egg in wet mass increased for absorbing moisture while incubating.2)The embryos employed about 10%,30% and 20% of the total egg energy in the periods of 0-20,20-30,and 30-35 days of incubation,respectively.3)The embryos grew slowly during the first 20 days,then grew rapidly.4)Approximately 63.4% dry material,32.7% non-polar lipids and 59.6% energy in the contents of fresh eggs were transferred to the hatchlings.5)Inorganic material in both yolk and eggshell was used by the embryos in development.The transition ratios of dry material and non-polar lipids as main energy-substance,and the proportion of residual yolk in hatchlings are lower than those reported for snakes.The lower ratios maybe related to the longer slow-phase of embryonic development in this species.
serum IgM in Carassius auratus was purified by precipitation of ammonium sulfate saturated solution followed by Sephadex G-200 chromatography.Then we made rabbit polyclonal antibody against serum IgM and linked it to Sepharose 4B to made affinity column,with which IgM was separated from skin mucus.The results showed that many other proteins were removed from serum by precipitation of ammonium sulfate,IgM could reach a purity of above 80% by Sephadex G-200 chromatography purified further,and the molecular weights of its heavy chain and light chain were 79 kDa and 25 kDa respectively.The rabbit polyclonal antibody affinity column had good capacity of purifying skin mucus IgM,whose heavy chain was 88 kDa.The rabbit antibody only recognizes the heavy chain of serum and skin mucus IgM by Western blot analysis.The result of ELISA indicated that IgM concentration in serum was higher in spring and summer than in autumn and winter.
Using the neural tracer biotinylated dextran amine and the immunohistochemical methods,we found that high vocal center (HVc) in Emberiza elegans received projections from the auditory area-field (L),nucleus interfacialis of midneostriatum,magnocellular nucleus of the anterior neostriatum (MAN),nucleus uvaeformis,and locus ceruleus of pons;HVc projected to the robust archistriatum (RA) and area X of lobus(X).HVc shell projected to the RA cup and received from L.As there were many neural connections among the vocal control and learning pathway,and the auditory center,vocal learning may depend on a feedback of listening senses.Substance P (SP) labeled neurons distributed in HVc,RA and MAN.SP labeled fibers and terminals distributed in X,the nucleus dorsalis medialis,the nucleus hypoglossi,pars tracheosyringealis,the nucleus ovoidalis shell,the shell of mesencephalicus lateralis,pars dorsalis,and the nucleus intercollicularis.SP widely distributed in vocal-auditory centers,and may involve in their activities.
In order to investigate the application of mass spectrometry (MS) in the renaturation and purification of synthetic peptides,ω-conotoxin MⅦA was chemically synthesized by a solid-phase method.The sample was oxidatively treated in a glutathione-containing buffer,and then purified by ion-exchange chromatography and RP-HPLC.The renaturation and purification efficiencies of synthesized ω-conotoxin MⅦA were subsequently analyzed by MALDI-TOF-MS and tandem electrospray mass spectrometry (ESI-MS/MS).Meanwhile,using an electrophysiological method,its biological activity was also measured.Mass spectrometric and electrophysiological analysis revealed that renatured and purified ω-conotoxin MⅦA possesses the same conformation and physiological activity as those of natural ω-conotoxin MⅦA.
220 bp fragments of Sox gene HMG-box in Alligator sinensis were amplified by PCR,and then subcloned and sequenced.Four different Sox genes were thus identified in both male and female.The encoded amino acid sequences exhibited 91%,96%,100%,and 96% of sequence homology with those reported for human SOX gene HMG-boxes,respectively.According to nomination system of human SOX genes,the newly identified Alligator sinensis Sox genes were named as ASSox1,ASSox2,ASSox11,ASSox22,respectively.There was no sexual difference in the four fragments.The amino acid sequences coded by Sox genes from amphibian,reptile,bird,and human showed a high degree of sequence homology within the respective four clusters,as revealed in phylogenetic tree constructed.The results indicated that Sox genes were highly conservative in phylogeney.
The morning song of five garden birds in Hangzhou was recorded at a fixed site,and for certain individuals in spring.The records were then processed with a computerized analysis system,resulting in that 1)there was a certain time-sequence of beginning songs for the species sharing the same range:Turdus merula sang always first,and Parus major,Pycnonotus sinenesis,and Copsychus saularis sang in an order changing monthly;2)the principle frequency (PF) of songs of the species ranged between 2.4-4.1 kHz,and were significantly different between species except that between Copsychus saularis and Passer montanus.The PF difference offers some basic information for further studies on the competition for frequency domain in the bird community.
Data on parental feeding rates of Twite Acanthis flavirostris were collected at Haibei Alpine Meadow Ecological System Station,the Chinese Academy of Sciences in 3 breeding seasons (May-August) in a period from 1999 to 2001.Using a closed-circuit television system,which included a camera nearby the nest and a monitor 35-40 m away from the nest,the feeding courses were seen.There were no differences in the feeding rates among the years,and also no difference between male and female parents.The total feeding rate of parents did not change with the age of nestlings,and with time of day,but the rate of males was higher than that of females before twilight,and reversed during twilight.The rate of males was higher than that of females before 6 days of nestlings age,and then the rates closed to the same level.Those sexual differences can be related to the differentiation of roles in rearing nestlings except the feeding:females were exclusively in charge of keeping warm for and sheltering nestlings from strong sunlight,and removing feces of nestlings from nests.Those results were in keeping with the theory of parental investment in monogamous avian.
After 6th-instar larva Helicoverpa armigera was fed on non-steroidal ecdysone agonist RH-2485,proteins and esterases in some tissues of them were examined,and the slices of body wall were observed with optical microscopes.SDS-PAGE resulted in that the expression of a major protein decreased in fat body and body wall of the group fed for 24 h and 48 h;Native-PAGE indicated that the expression of new esterases appeared in hemolymph and midgut of the group fed for 48 h.The body wall structure of the larva fed for 24 h showed some features of ecdysis (mesocuticle and endocuticle became vacuoles,and epicuticle and exocuticle separated from epidermis),and abnormal ecdysis (epidermis became obviously thinner than normal one).These results enhanced our knowledge of the mechanism of RH-2485 killing Helicoverpa armigera.
Specimens were collected in four major plateau wetlands in Lashihai Nature Reserve in August and October 2001,and October 1999.For determining the status of fishes fauna,literature was referenced,and fishermen were interviewed in the Participated Rural Augmentation(PRA).A combination of the results of species-identification of 4550 specimen and PRA,as well as checking historical records resulted in:there are 25 fish species,belonging to 21 genera,10 families and 5 orders;of 25 species,18 were introduced,7 were indigenous,and 3 species were highly endangered or even extinct.Triplophysa (Triplophysa) venusta was first recorded in this area.The fauna mainly consists of introduced species,and the indigenous are disappearing.
Two specimens were collected from Luosuo River (a branch of Lancang River),China in July 2001.They are identified as Barbodes gonionotus,a new record in the Chinese fish fauna.This new record differs markedly from the other species of genus Barbodes in that it has 6-7 branched anal-fin rays.
Snake venoms are a rich resource of non-enzymatic C-type lectins.Based on their structure and function differences,snake venom C-type lectins can be classified into two categories:1) true C-type lectins with Ca[2+]-dependent saccharide-binding activity and 2) C-type lectin-like proteins.Comparatively,true C-type lectins have higher structural similarity and lower functional diversity;C-type lectin-like proteins have lower structural similarity but distinct biological activities.They can act on blood coagulation factors and platelets through specific protein-protein interactions and exhibit anti-coagulant or pro-coagulant activities.