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2002年  第23卷  第3期

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研究论文
Phylogeny of the cyprinid subgenus Cyprinus (Mesocyprinus) is elucidated based on both external and osteological features.All five species of Cyprinus (Mesocyprinus) are including in the ingroup in addition to two Cyprinus (Cyprinus) species.Procypris merus was treated as outgroup in comparison.A total of 48 characters were identified as variable among ingroup and outgroup.Phylogenetic analysis was accomplished using Parsimony and Bootstrap methods with Branch-and-Bound search of PAUP[*].There are 28 characters remaining useful after excluding unpolarized characters and autapomorphies of terminal taxa.Analysis of the characters resulted in one tree with a length of 69 steps,Consistency Index (CI) of 0.7246,CI excluding uninformative characters of 0.6122,and Retention Index (RI) of 0.6346.It is apparent that the Mesocyprinus group consisting of five species is a polyphyletic group.This result suggests that subgenus Cyprinus (Mesocyprinus) should be suspended.
The genus Sinocyclochei lus (Cypriniformes:Cyprinidae:Barbinae) is endemic to China and only found in Yunnan,Guizhou and Guangxi Provinces.The nuclear DNA content of two species and the ploidy level of three species in Sinocyclocheilus had been determined in the middle of 1980s.In recent years,more and more new species were reported in this genus.Therefore,it is necessary to analyze the nuclear DNA content,ploidy level and evolution of the species in the genus.In the present paper,by means of the red cell spreading-Feulgen staining-cytophotometry technique,we have measured the nuclear DNA content of 17 species in Sinocyclocheilus from Yunnan,Guizhou and Guangxi Provinces and distributed in the drainage of Nanpanjiang,Jinshajiang,Beipanjing,Yuanjiang,Hongshuihe and Youjiang rivers.The results showed that the nuclear DNA content of all 17 species were between 4.19 and 4.86 pg,as the same level of the related tetraploid species,doubled that of the related diploid species.It is likely that all of these 17 species and the whole genus Sinocyclocheilus have tetraploid origin.
By means of ion-exchange chromatograph and reverse phase HPLC,a new neurotoxin,named as Hainantoxin-Ⅴ (HNTX-Ⅴ),was isolated from the venom of the spider Seleconosmia hainana.The molecular weight of HNTX-Ⅴ was 3 969.5 Da measured by MALDI-TOF mass analysis.Under whole-cell patch-clamp mode,HNTX-Ⅴ could inhibit the tetrodotoxin-sensitive (TTX-S) sodium currents while it had no significant effect on tetrodotoxin-resistant (TTX-R) ones on the dorsal root ganglion (DRG) neuron of adult rats.The inhibition of TTX-S sodium currents by HNTX-Ⅴ was concentrate-dependent with the IC[50] value of 46.8 nmol/L.The toxin did not effect the active and inactive time course of currents and did not have the effect on the active threshold of sodium channels and the voltage of peak inward current either,indicating that HNTX-Ⅴ inhibited mammalian voltage-gated sodium channels through a novel mechanism distinct from other spider toxins such as δ-ACTXs.We suggested that HNTX-Ⅴ maybe target the site 1 of sodium channels in a similar manner to TTX,Saxitoxin and μ-conotoxins.
This study was conducted to evaluate the cryoprotective function of sugars in two freezing media (TTE and TEST) by comparing the spermatozoa morphologic change of rhesus monkey before and after cryopreservation using transmission electron microscopy.The results showed that the structure of acrosome integrity,nuclear and tail of most spermatozoa cryopreserved with TTE was similar with that of fresh spermatozoa,except for the slight swell of plasma membrane.However,in spermatozoa cryopreserved with TEST,the plasma membrane were fluctuated,swelled and broken,the acrosome integrity and nuclear were damaged,and the structure of tail were changed significantly.It demonstrated that TTE is a suitable freezing media for rhesus monkey spermatozoa cryopreservation.Sugars exert cryoprotective roles by protecting the intact of plasma membrane and acrosome integrity,but the protective roles of sugars are significant different.
From 22 May to 11 June 1999 in the Xinjiang Province of the Peoples Republic of China,the incubating behaviour of two female houbaras with the help of a temperature logger egg was successfully monitored.As a rule,the female showed a bimodal daily activity pattern (morning and evening) during the incubation stage.In average,a female will leave her nest 3 to 9 times every day for periods ranging from 8 to 26 minutes.During incubation,the female spent (94±2)% of her daily time in the nest.The average temperature of the egg varied from 31.9 ℃ to 36.5 ℃ while the female attended the nest; that dropped to (24.9±3.2) ℃ while the female left and unattended the nest.The average daily egg temperature increased from 31.9 ℃ to 36.2 ℃ as the incubation advanced,following the increase in air temperature.
Trema orientalis seeds dispersing by birds were studied at Mengsong and Menglun areas,Xishuangbanna,Yunnan Province.It was observed and recorded that species of birds eating T.orientalis fruits in the field.Different types of mist nets were employed at forest edges and gapes,as well as near the ripe fruit trees.Birds to eat the T.orientalis fruits were mist-netted in field,each bird was placed in a separate cloth bag,its excreted feces was collected,and the seeds in bird feces were checkuped.36 species of birds have been recorded to consume the T.orientalis fruits,and fecal samples from 26 species by mist-netted were gotten.Germinating experiments were conducted through sowing a kind of ripe fruit and two kind of seeds of T.orientalis in 4 conditions.The ripe fruits of T.orientalis were directly sowed,they could not germinate and were easily decay.The seeds separated by handwork from the fruits could germinate.The seeds excreted by nature from birds had a very high rate of germination.It is suggested that the seeds had changed from dormancy into activity while the T.orientalis fruits consumed by the birds.Birds took the seeds to the forest edges and newly cut areas that more suitable for germination and seedling growth.There are ecology reciprocal role between birds and T.orientalis.
The effect of forest patch size on reproductive success of Magpies (Pica pica) in fragmented secondaryforests was studied in Zuojia Nature Reserve and Tumenling Area of Jilin Province from 1999 to 2000.12 forest patches ranging in size from 3.5 to 46.6 hm[2] were located by using GPS,and classified as large (>20 hm[2],n=4),medium (10-20 hm[2],n=3) and small (<10 hm[2],n=5) patches.2 control samples (20 hm[2]) were selected in the extensive forest (>200 hm[2]) being contiguous to those patches.The data on breeding success,laying date,clutch size,egg weight,brood size and fledged number of the Magpies were collected in 12 patches and 2 control samples.The results show that:1)the patch size influences the reproductive success signigicantly among forest categories;2)the mean laying date in the control samples and large patches is 11.62 d earlier than that in the small ones;3)the clutch size in the control samples and large patches is bigger than that in the small ones;4)the mean weight of eggs doesnt differ between all patches and control samples,but the hatching rate and fledgeling rate are the lowest in the small patches(51.17% and 42.88% respectively),the hatching rate is the highest in the large patches (72.12%) and a little lower in the control samples (71.93%),and the fledgeling rate is the highest in the control samples (65.45%) and next in the large patches (62.71%);5)the low reproductive success of the small patches in the secondary-forests mainly caused by a high rate of nest failure.
The ultrastructure of the X-organ sinus gland complex in sexually immature Chinese mitten crab Eriocheir sinensis was examined under the electron microscope.The sinus gland (SG) is composed primarily of nerve terminals and glial cells.The terminal contains a great number of membranebound granules,mitochondria,rough endoplasmic reticulum and electron lucent vesicles.The profiles of the terminals are sometimes exhibited finger like projections.The X-organ (XO) locates at the ventral surface of the medulla terminalis ganglion in the eyestalk,oppositing to SG.According to the features of granule size,shape,electron density and cytoplasm,6 types of terminals in SG and 7 types of neurosecretory (NS) cells in XO were identified.The release process by exocytosis of the granules in SG was observed and a tentative comparison was made for the granules between different types of terminals and NS cells.It seemed that they had a good correspondence since no change in electron density and just a slight increase of sizes was shown.
Three new species of the genus Caenis (Ephemeroptera,Caenidae),Caenis aspera sp.nov.,Caenis bicornis sp.nov.and Caenis lubrica.sp.nov.,are described from Hong Kong,China.All type specimens are deposited in the Insect Collection of Department of Entomology,South China Agricultural University,China.
In the present paper a new species of Sinodina is described. 1 Type material Holotype,♂,China:Taoyuan,Yongsheng County,Yunnan Province (26°75′N,100°70′E),1100 m,20-Ⅷ-1981,coll.CHEN Guo-xiao.Paratypes,10♂♂,10♀♀,same as holotype.Holotype is deposited at Institute of Zoology,the Chinese Academy of Sciences,Beijing. 2 Description Sinodina yongshengica Chen et Liang,sp.nov.(Fig.1:a-k) Rostum reaching to the middle of 2nd segment or to the end of 3rd segment of antennular peduncle;dorsal border bearing 5-9 teeth,1-2 of which situated on carapace behind orbit;tip bearing a footh;ventral border bearing 1-2 teeth. Telson without a shorter median tooth on the distal margin of the dorsal surface.Dactylus of lst pereiopod shorter than palm;carpus of 2nd pereiopod longer than merus;3rd pereiopod sexually dimorphic,dactylus armed 16-19 spines in males and 13-16 spines in females;dactylus of 5th pereiopod armed 36-44 spines. Uropodal diaeresis with 11-15 spines. 3 Remarks The present new species is closely allied Sinodina ijiang Liang et Cai,1999,but differs from the latter in following features:telson without a median tooth;ultimate of 3rd maxilliped covering with many spines on the distal portion; dactylus of 1st pereopod shorter than palm;carpus of 2nd pereopod longer than merus; spines of 3rd-5th pereopods less in number;teeth of diaeresis more in number;eggs smaller in size.
Aggregating diploid embryonic cells with tetraploid embryonic cells forms 2n/4n chimaeras.Tetraploid cells demonstrate a preferential distribution in chimaeras during embryonic development.Tetraploid cells are preferentially allocated to the extraembryonic tissues,such as placenta,rather than the fetus itself.This paper summarized methods of producing 2n/4n chimaeras,and developmental characteristics and possible applications of the chimaeras.
Litter size is a key parameter in understanding mammalian reproductive patterns.The amount of surviving litter size,the offspring size and the state of their mothers determine the reproductive fitness together.There are tradeoffs between the litter size and offspring size.While the offspring survival depends on the offspring size.However,the relationship between the litter size and offspring survival can still not draw a constant conclusion.The maternal fitness also is symbolized by the survival of young,so the litter size directly correlate with the maternal variables including the body mass and metabolic rate.There is the negative effect on the maternal survival,but the relationship between the litter size and maternal survival is unclear.In short,the study of litter size needs further explore,while fortunately recent advances in molecular techniques and the other means provide options for those as well.
Here studied the mechanism of responded pattern of 33 neurons to sex pheromone in the antennal lobe (AL) of male moths Agrotis segetum.Pressure injecting 100 mmol/L GABA into AL,GABA can elicit inhibitory responses of slow hyperpolarization and long time inhibition of background spiking,alike which caused by sex pheromone in the same neuron.But GABA can not act on the excitation evoked by pheromone.Low-Cl[-] saline caused that the IPSP to reverse the hyperpolarization,excitation evoked by pheromone was prolonged,and the distinct separation between bursts disappeared.Bicuculline was as a GABA[A] receptor antagonist in vertebrates,and a water-soluble form of this agent was used for pressure ejection into the AL neuropil.Bicuculline increased the spike frequency in tested neu rons,even strengthened the excitation phase acted by pheromone,and the hyperpolarization and spike-inhibition produced by pheromone was replaced by excitation.The effect was reversible by washing in normal saline.Results indicate that the hyperpolarization is related to GABA receptor,which responds to the sex pheromone in AL neurons in the male moths Agrotis segetum.
To study the somatic function of the micronucleus of the ciliated protozoan Pseudokeronopsis monilata,amicronucleate cells were generated by removing the micronuclei shortly before binary fusion.Most of the amicronucleate cells derived from regeneration were crippled in morphology,characterized by the defective adoral zone of membranelles.At the same time,the number and the size of macronuclei in some amicronucleates become unstable.These suggest that the micronuclei play an important role for maintaining the stable structure of the cell and the macronuclei.
In order to provide scientific grounds for the prevention and treatment of penicillic acid poisoning on the poultry and the mechanism of penicillic acid toxicosis,the toxicity of penicillic acid has been investigated in broiler chickens.By the artificial contamination,we observed the pathological manifestation and measured the changes of blood biochemical value,the residue of penicillic acid in tissue and organs of the broiler chickens within 60 days.The results showed that:1)major pathological changes was fatty and vacuolar degeneration of hepatocytes,cloudy swelling of renal epithelial cells and myocardial cells;2)the contents of MCV and MCHC in poisoned groups were less than that in control group,whereas the activities of SGPT,LDH and AKP in the formers were higher than those in the latter;3)as for the distribution of penicillic acid,the amount was the highest in liver,and the residue in kidney outweighed that in heart.It was understandable that there was a relation between the residue of penicillic acid and the degree of lesion.The target organ of penicillic acid poisoning was liver.
High molecular weight genomic DNA from the grasshopper,Dasyhippus barbipes was extracted and partially digested with Sau3AI,10-20 kb DNA fragments were collected by 10%-40% sucrose density gradient centrifugation,and ligated into lambda EMBL3 vector. Recombinant DNA was packaged in vitro,then construction of the genomic DNA library in Dasyhippus barbipes was completed.The titer of the library is 2× 10[5] pfu/mL,and the genomic DNA library consists of 99% genes of Dasyhippus barbipes.
The elastic membrane of rAts ascending aorta,thoracic aorta,abdominal aorta and common iliac artery at developing and aged has been observed with CLSM.At the same time,the area of the wall and the cavity of blood vessels,and the thickness of the tunica media have been observed with LM.During the aging,the microstructure of the ascending aorta,thoracic aorta,abdominal aorta and common iliac artery changed,such as the fluorescence intensity of the elastic membrane,the area of the wall and the cavity of blood vessels increased dramatically,and the tunica media thickened clearly.Corresponding to the variations of the structure,the arterial function changes greatly during the aging.