Table of Content

    20 February 1986, Volume 6 Issue 1
    ZHENG Zixiu, ZHONG Jinyan, LI Jingyan
    1986, 6(1):  1-6. 
    Asbtract ( )   PDF (3131KB) ( )  
    Related Articles | Metrics
    5SrRNA is a small molecular ribonucleic acid existing in the large subunit of ribosomes of prokaryotic and eukaryotic cells. It is one of the most suitable molecule for studying molecular evolution and plays an important role in protein biosynthesis.A simple and reliable procedure of the purification of 5S ribosomal RNA from the Rhesus monkey liver is described.The liver was removed from a freshly killed Rhesus monkey and homogenized with two volumes of the "TSMK" buffer containing 0.005mol/L tris-HCl pH7.5, 0.25mol/L Sucrose. 0.005mol/L MgCl2,0.025mol/L KC1 and 0.2% bentonite.The homogenate was centrifuged at 10000 Xg for 20 min. The supernatant (cytoplasmic fraction) was treated with water-saturated phenol containing 0.1% 8-hydroxyquinoline and 0.2% sodium dodecyl sulfate-bentonite, centrifuged at 10000 xg 40 min and then total RNAs was precipitated by cold 95% ethanol. Low-molecular weight RNAs was extracted from the precipitate with 1 mol/L sodium chloride solution. Then,the low molecular weight RNAs was purified by ion-exchange chromatography of DEAE-Sephadex A-50 and eluted with a linear concentration from 0.375mol/L to 0.525mol/L NaCl.The 5SrRNA was purified from low molecular weight RNA2 by 10% preparative polyacrylamide gel slab electrophoresis in the presence of 7mol/L urea, using 90mmol/L tris-boric acid pH8.3, and 2.5mmol/L ethylenediamine tetraacetic acid disodium buffer system. The 5SrRNA band was excised from the preparative slab gel under 254nm ultraviolet light,eluted with 10mmol/L tris buffer (pH8.O) containing 350mmol/L KC1, lOmmol/L MgCl2, 1mmol/L EDTA and dried in vacuo.Identification of polyacrylamide gel electrophoresis and ultraviolet absorption spectrum for pure 5SrRNA of the liver of Rhesus monkey indicated that only a single band on denatured polyacrylamide gel and a typical ultraviolet absorption peak of nucleic acid were shown. The A260/A230 ratio was 2.08 and A260/A280 ratio esd 2.07.
    XU Kefen, GAO Xingyi
    1986, 6(1):  7-12. 
    Asbtract ( )   PDF (4611KB) ( )  
    Related Articles | Metrics
    This paper describes the karyotypes of three species of the Canidae and Mustelidae of mammals caught in Xinjiang. The specimens of chromosomes are prepared by the methods of peripheral blood lymphocyte culture and the conventional bone marrow culture.Tibetan Fox (Vulpes ferrilatus) is 2n = 36. Its chromosomes are divided into two groups: the first group(1st-15th pairs) is metacentric(M) and the second group(16th?8th pairs) is submetacentric(SM).In the 3rd, 4th, 5th and 6th pairs of chromosomes G-bands are so obvious that they are easily identified.For Tiger Stoat (Vormela peregusna), 2n = 38. Its chromosomes are divided into thres groups: the first groupdst-llth pairs) is M; the second group(12th-16th pairs) is SM; and the third group (17th-18th pairs) is acocentric(A). The chromosome X is M. As the chromosome Y is so small that its centriole cannot easily be identified. There is a secondary constriction on each of the long arms of 1st-3rd pairs of the chromosomes.For Musked polecat(Mustela eversmanni), 2n = 38. Its chromosomes are divided into 3 groups; the first group (1st條lth pairs) is M; the second group(11th-16th pairs) is SM. and tbe third group(17th-19th pairs) is A. There is a secondary constriction on the arm of the 18th pair of the chromosomes.The chromosome numbers, morphology and N.F, in the karyotype of Musked polecat reported above are more or less different from those reported by rpaφoдaTCKнй, 1976, (New Siberian Is.) and by Wang Zongren, 1984, (Huailai, Hebei). These differences are mainly caused by Non-Robertsonian translocation. The differences of Karyotypes of Musked polecat are related to the subspecies differentiation.
    Andrew T. Smith1, Harriet J. Smith2, WANG Xuegao3, YIN Xiangchu3, LIANG Junxiun3
    1986, 6(1):  13-32. 
    Asbtract ( )   PDF (3208KB) ( )  
    Related Articles | Metrics
    ZHANG Jie
    1986, 6(1):  45-56. 
    Asbtract ( )   PDF (2967KB) ( )  
    Related Articles | Metrics
    This paper deals with the breeding characteristics of striped hamsters in Daxing, Beijing, from September, 1982 to March, 1985. Among the 1003 specimens collected, 472 are males and 531 are females. The reprodution status are as follows:1. The sex ratio of all the specimens proves that the female accounts for a larger proportion than the male, and such is the case in the young and subadult groups, but males are more than females in the adult and old groups.2. Emphasis of the studies is laid on the correlationship between the testis weight and the body weigiht. The testis weight of adults is 0.7g and over, the testis weight of subadults is 0.15-0.69 g, the testis weight of youngs is O.lg and below. The male is involved in the reproductive activities throughout the year except a short period (from mid-Nov. to next early Jan.).3. The beginning of the breeding period varies with years. In 1983 and 1985 it began in Feb. and in 1984 it started in March. Young striped hamsters became matured within 2 ?3 months. Females also stop breeding from Nov. to next Jan. and they have two breeding peaks in a year. The first peak was between Spring and Summer and the second was between Autumn and Winter. Adult striped hamsters breed 2-3 times each year. In 1983 the annual average litter size of female adult was 5.844±0.212 and 6.821 ± 0.898 in 1984.4. The ecological life-span of a female striped hamster involved in reproductive activities is about one year.The reproductive indices are calculated by the following formulas I = NE/P, I representing the reproductive index; P the total number of captures; N the number of pregnancies; E the average number of litter size. They showed also reasonal and annual changes.
    ZHAO Xiaofan, LU Haoquan
    1986, 6(1):  57-62. 
    Asbtract ( )   PDF (4673KB) ( )  
    Related Articles | Metrics
    The striped field mice are the main pest rodents in most areas in our countiy.They spread several diseases of which the epidemic hemorrhagic fever, in particular, threatens the public health. Although many scholars have studied their morphology, classification, distribution and habits, the study of chemical indexes of these mice hasn't been reported. Their serum proteins, serum lactate dehydrogenase(LDH), crystalline lens LDH and muscle LDH, serum esterase and myogen have been analysed by means of polyacrylamide gel disc electrophoresis. The results obtained are as follows:1. All the striped field mice caught from Shandong Province; Yixing city, Jiangsu Province; Hefei city. Anhui Province are highly similar in LDH isozymes and myogen. That means that they belong to the same species, but there is a subspecies differentiation among them, because their serum proteins reveal differences.2. The animals from Yixing and Hefei belong to the same Subspecies: A.a.ningpoensis, and those from Shandong Province belong to another A.a. pallidior,The differences of the two subspecies are rather clear in some biochemical characters.No A.a.ningpoensis was found in Shandong Province.
    ZONG Hao
    1986, 6(1):  63-72. 
    Asbtract ( )   PDF (2901KB) ( )  
    Related Articles | Metrics
    This review was written on the basis of some major books about the circadian rhythm and many papers published recently. It is introduced as follows:I .The early history and development of the circadian rhythm researchThe astronomer,De Mairan (1729) was the first to make an experiment showing that plant leaves periodically move in constant darkness and temperature.De Candlle(1832) clearly realized that leaves movements were caused by inherent diurnal rhythm, later on,the inhertance of the mammlian diurnal rhythm was further verified by Aschoff in 1955.Aschoff(1954) introduced the term "zeitgeber" and considered that light is a most important one.Before long, the circadian temperature indenpend-ence was proved by Rawson in 1956 and Sweeny et al. in 1960. Nieborj (1958) observed the circadian change of the cell nucleus size in rats.Halb-erg(1953) had a remarkable discussion that DNA and RNA both play a part in circadian rhythm.Application of feedback theory, black-box analysis as well as theory of oscilator and serve mechanism pushed the biolgical research a great forward. It was reported that biochmical feedback system may serve as the mechanism of biological clock. Establishment of models was currently ava- ilable in 1960's and a great number of models have been emerged.An important models were coupled oscilltor model of Pittendrigh et al.in 1957 and Wever model of Wever et al. in 1965.Ⅱ . Present situation and trendsLocation of biological clock remained elusively for long time. Many authors, Hedlud,(1977); Hoffmann, (1981)and Illnerova et al. (1984) have showed successfully a "pineal clock" and proposed that pineal gland serve as an important intermediary in the synchronization of mammalian circadian rhythm. Moor (1980) did great achievements concerning pacemaker of the circadian rhythms.More and more researchers paid much attention to what's going on in biological rhythm at the biochemical and molecular levels.Such as Chance's feedback loop model in 1967, Watson's tape-reading trascription model in 1970 and Njus's membrane model in 1974, which made some suggestions in clock mechanism.Macroscopic work mostly denotes some ecological researches, such as, "seasonal rule",oxygen consumption rhythm, functional taxonomy, etc. It is worth wiling that Aschoff(1964) offered the Aschoff Seasonal Rule which seems successful in practical applications.In China circadian rhythm research rose from 1970's. Circadian locom-otor rhythm in pikas, voles, zokors, and tree shrews were recorded, and oxygen consumption rhythm have been studied in pikas and zokors.In mic-rocosmic area, circadian rhythm of the corticosterone level and the electroencephalogram of sleep and wakefulness have been documented in pikas, rats and tree shrews.