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1998年  第19卷  第6期

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研究论文
The blood samples of 19 individuals of Sichuan snub-nosed monkey (Rhinopichecus roxellana) from two different geological regions were investigated in this study.All of forty-four genetic loci surveyed were monomorphic.Its mean heterozygosity,a measurement of genetic diversity,was zero.Considering the larger size of population and better living state of Sichuan snub-nosed monkey than Yunnan snubnosed monkey (R.bieti),we inferred that Sichuan snub-nosed monkey might have experienced previous bottleneck,and after this,its population recovered.The speculation is also supported by geological data.
The medium in which prehatching Xenopus laevis embryos were cultured (hatching medium) can solubilize vitelline envelope (VE) of dejellied uterine eggs and dimethyl casein.Western blotting analyses with antibodies against hatching enzyme revealed the presence of 60 kD,and occasionally 40 kD molecules in hatching medium.Results on VE-solubilizing activity assay indicated that the fractions containing 60 kD molecules exhibited strong solubilizing activity but those containing 40 kD alone did not,although both fractions exhibited the same level of proteolytic activities.However,solubilization of VE was obtained when the 40 kD fractions were mixed with an extremely low concentration of 60 kD fractions that can not solubilize VE by itself,or were applied to the VE-that had been pretreated with a low concentration of 60 kD fractions.We proposed that recognition and/or processing of VE by CUB repeats in 60 kD molecules made VEs solubilization possible by 40 kD molecules.
It was infered that β-agkistrodotoxin-binding protein is presumably a novel presynaptic functional protein involved in neurotransmitter release.This paper reported studies on solubilization of β-agkistrodotoxin-binding protein from Torpedo californica electric organ,a tissue rich in synapses.The binding assay of this protein was established using a PEG precipitation method,and its binding properties with [125]I labelled β-AgTX was preliminarily determined.The results showed that the density of β-AgTX-binding sites in this tissue is relatively high (much higher than that of rat brain).B[max] is 1580 fmol/mg protein and K[D] value is 5.5×10[-9] mol/L.Triton X-100 was proved an effective detergent for the extraction experiment with a yield of about 50%.Thus a hopeful beginning for isolation and purification of β-agkistrodotoxin-binding protein was accomplished.
The effect of abdomnoinjection prostaglandin E[1](PGE[1]) on antral myoelectric activity was investigated in 30 Wistar rats chronically implanted with Ag/AgCl bipolar electrode on the serosal surface of antrum.It was found that PGE[1] could 1) decrease the amplitude of slow wave;2) cause biphasic changes of fast wave,usually with enhancement before giving way to inhibition;3) cause diarrhea.The inhibitory action of PGE[1] on slow wave and fast wave might be not mediated via adrenergic α and β receptor,and the excitatory action of PGE[1] on fast wave was probably mediated via cholinergic M receptor.
Pliable-shelled eggs of Takydromus septentrionalis increased in wet mass over the incubation due to absorbing water from the substrate.The levels of substrate moisture significantly influenced final masses of the eggs incubated at 26 and 28℃.Eggs gained more mass in wetter substrates than in drier substrates.In contrast to those at 26 and 28℃,final masses of the eggs incubated at 24℃ were independent of the level of substrate moisture.Due to the positive relationship between final and initial egg masses seen in all cases,variations in final egg mass could be partly explained by the variation in initial egg mass.Within the range from 24 to 32℃,incubation temperature significantly influenced duration of incubation,hatching success,and size,mass,and sprint speed of hatchlings,with the eggs incubated at 24 and 26℃ exhibiting higher hatching successes and producing larger,heavier,and faster-running hatchlings.Within the range from -220 to 0 kPa,incubation hydric environments had no impacts on duration of incubation,hatching success,and size,mass,and sprint speed of hatchlings.Incubation thermal and hydric environments did not determine sex in T.septentrionalis.
The percentages of Ⅰ-Ⅲ instars and Ⅳ instar+wingless agamic females of tobacco aphid,Myzus nicotianae (Blackman),on flue-cured tobacco K-326 between different leaf phyllotaxy were quite different.The difference obviously depended on the aphid density.The caculation of seven spatial pattern indices indicated that the vertical spatial distributions of the Ⅰ-Ⅲ instars and Ⅳ instar+wingless agamic females on tobacco were contagious distribution at every density.The mean value of the spatial pattern indices showed the aggregating intensity of Ⅰ-Ⅲ instars was stronger than that of the Ⅳ instar+wingless agamic females.The vertical spatial distribution of Ⅰ-Ⅲ instars,Ⅳ instar+wingless agamic females and whole wingless aphids were analyzed by ways of three regression models.It demonstrated that the distributions of the tobacco aphids at any density were contagious,and the aggregating degree was density-dependent.The basic component in the distribution was the individual groups and the population density had little influence on the relative aggregating degree of the basic component in the distribution.
Fishes of the genus Sikukia (Cyprinidae:Barbinae) can be distinguished from other fishes of Barbinae in several characters,such as snout shorter,eyes bigger,adipose eyelid absent etc.So far three species have been recorded.We report a new species S.longibarbata in this paper,so there are totally four species now.All of them can be found in Lancangjiang river,Yunnan.
This paper deals with three new species of Lamiine beetles from Yunnan,China.They are:Thylactus dentipennis,Blepephaeus nigrostigma,and Sternohammus yunnana.The genus Sternohammus Breuning is recorded for the first time from China.All the type specimens are deposited in Insect Collection,Southwest Agricultural University.
Neogamasus anomalus sp.Nov.;Neogamasus crispus sp.Nov.。
In the examination of marine fishes of Dongshan Island,South Fujian,China,two new species of Acantholpidae were collected.These specimens are deposited in Marine Biology Laboratory,Science Center,Shantou University.All measurements are in millimetres,unless otherwise noted.
Many biochemical,physiological and behavioural processes in organisms ranging from microorganisms to vertebrates exhibit circadian rhythms driven by endogenous oscillators.Since the cloning of the biological clock gene period in Drosophila,the endeavor in two decades to understand the molecular components that constitute these oscillators has been rewarded:we now know the circadian rhythm is driven by four cogs:PER,TIM,CLOCK and BMAL1,and the mechanism which govern the circadian oscillation has been elucidated.This work on biological clock genes is spectacular not only for its heuristic value,but also because it illustrate the synegistic power of genetics and genomics.Given the evolutionary conservation of the mechanisms that govern the fundermental biological processes,the period story will greatly accelerate the reseach progress on human complex behavior.
Geostatistics has attracted the attention of many ecologists who need better explaining and modeling tools for describing spatial structure and patterns of organisms.This paper introduces the general methods of geostatistics,including variograms,h-scatterplots,correlograms,covariance measures.Geostatistics is independent of mean variance relationship and therefore can be used to verify more traditional methods of evaluation insect spatial structure.A lot of works have demonstrated how to analyze spatial structure of insect population with geostatistics.