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Effect of heterospecific DNA on the development of Rana nigromaculata. 异源DNA对黑斑蛙发育的影响。
Scientia Sinica Pub Date : 1981-03-01
L J Shi, Y C Yan, J Z Zhang, H Y Mo, Y Q Lu
{"title":"Effect of heterospecific DNA on the development of Rana nigromaculata.","authors":"L J Shi,&nbsp;Y C Yan,&nbsp;J Z Zhang,&nbsp;H Y Mo,&nbsp;Y Q Lu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Both the DNA of a balancer-bearing species (Cynops orientalis) and that of a non-balancer-bearing species (Rana nigromaculata), when injected into the fertilized eggs of R. nigromaculata, cause some tadpoles derived from the injected eggs to bear a single balancer-like process on the left operculum. Based upon these results, it may be so concluded that the occurrence of the balancer-like process in the tadpole is neither due to genetic transformation, nor due to balancer induction, but rather due to a non-specific developmental effect of DNA.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 3","pages":"402-6"},"PeriodicalIF":0.0,"publicationDate":"1981-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18271366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Acoustic signals and acoustic behaviour of Chinese river dolphin (Lipotes vexillifer). 中国江豚(Lipotes vexillifer)的声信号和声行为。
Scientia Sinica Pub Date : 1981-03-01
X Y Jing, Y F Xiao, R C Jing
{"title":"Acoustic signals and acoustic behaviour of Chinese river dolphin (Lipotes vexillifer).","authors":"X Y Jing,&nbsp;Y F Xiao,&nbsp;R C Jing","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Chinese river dolphin's (Lipotes vexillifer) underwater acoustic signals can be divided into two classes, short-duration signal (pulse train or single pulses) and long-duration signal (whistle). In this paper, time waveforms of these signals are presented and the characteristics of the signals are discussed. The experimental results on this dolphin's acoustic behaviour are given. A sinusoidal pulse with duration of about 300 ms is used as the calling signal. In a certain frequency range, as soon as a calling signal is transmitted the dolphin answers with 2 or 3 whistles. The frequency range of sensitive response is from 4 to 7 KHz, in which the answering rate reaches 100%. When the dolphin's acoustic signals recorded on the tape are transmitted into the water it swims directly toward the transducer. When noise and music are transmitted the dolphin does not respond at all.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 3","pages":"407-15"},"PeriodicalIF":0.0,"publicationDate":"1981-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18271367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Theory on prospect of population evolution processes. 种群进化过程前景理论。
Scientia Sinica Pub Date : 1981-03-01
J Song, J Y Yu, G G Li
{"title":"Theory on prospect of population evolution processes.","authors":"J Song,&nbsp;J Y Yu,&nbsp;G G Li","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>This paper is aimed at investigating the dynamic process of population growth applied to population of the People's Republic of China. The discrete and continuous models of population evolution process are revised and adjusted to suit the social conditions of China. The relationship between two kinds of models is established. A series of new formulae of demographic indices are studied and defined as functions on the negative space of generalized solutions of the population equation. Based on survey data collected in China for recent years, the prospect of population growth according to different projections is offered for a one-hundred-year period from now on.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 3","pages":"431-44"},"PeriodicalIF":0.0,"publicationDate":"1981-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18271369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Induction of gastric adenocarcinoma in rats by N-methyl-N-nitro-N-nitroso-guanidine and ultrastructural changes of epithelial cells of the pyloric gland region. n -甲基-n -硝基-n -亚硝基胍诱导大鼠胃腺癌及幽门腺区上皮细胞超微结构改变。
Scientia Sinica Pub Date : 1981-03-01
Z X Zhang, Y Q Li, G R Li, Z X Sun
{"title":"Induction of gastric adenocarcinoma in rats by N-methyl-N-nitro-N-nitroso-guanidine and ultrastructural changes of epithelial cells of the pyloric gland region.","authors":"Z X Zhang,&nbsp;Y Q Li,&nbsp;G R Li,&nbsp;Z X Sun","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Rats of non-pure strain were allowed to drink N-Methyl-N-Nitro-N-Nitroso-guanidine (MNNG) solution (200-250 micrograms per milliliter) ad libitum. After 14 months, in addition to MNNG, each of them was fed with 1 ml of saturated NaCl solution once a week. During a period of 18 months, there were 5 cases of gastric adenocarcinoma and 2 cases of adenocarcinoma of the duodenum among 18 experimental rats. Besides, there were a few cases of papilloma of the fore-stomach and carcinoma of the lung. In 17 control rats, no tumors of the gastro-intestinal tract were seen. Microscopic examination of the mucosa of the pyloric gland region of the stomach in the experimental rats showed that the deep epithelial cells of the gastric pit exhibited a marked degree of proliferation and a malignant change had started in these cells. Electron microscopic observation of these epithelial cells revealed that the the proliferating cells showed only increased nucleocytoplasmic ratio, while those with atypical hyperplasia showed that the form of the nucleus and the changes in the basement membrane and intercellular junctions were somewhat similar to those of malignant cells. It is believed that increase in concentration of the carcinogens and prolongation of the time of contact with them may induce malignant tumors in the insensitive animal.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 3","pages":"416-22"},"PeriodicalIF":0.0,"publicationDate":"1981-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18271368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Expression of gene(s) in restricted fragment of lambda DNA in E. coli. λ DNA限制性片段基因在大肠杆菌中的表达。
Scientia Sinica Pub Date : 1981-02-01
D R Kuang, J K He, Q D Ju, Q H Gong, M Z Wang, X L Zhu
{"title":"Expression of gene(s) in restricted fragment of lambda DNA in E. coli.","authors":"D R Kuang,&nbsp;J K He,&nbsp;Q D Ju,&nbsp;Q H Gong,&nbsp;M Z Wang,&nbsp;X L Zhu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Restriction endonucleases EcoR1 and BamH1 are used to produce fragments pBR322C (375 bp) and pBR322B (3987 bp) from pBR322, and to produce lambda F2A (65.6--71.3% of lambda DNA, 2679 bp) and lambda F2B (71.3--81% of lambda DNA, 4559 bp) from EcoR1 restriction fragment lambda F2 (65.6--81% of lambda DNA) of lambda cI857S7 DNA. By recombining pBR322B and lambda F2B in vitro, a new plasmid called pCB2 carrying promoters and structural genes cI and cro is constructed. The desired strain with pCB2 is selected from 338 transformants for its AprTcs and for its immunity to lambda infection. The length of the pCB2 DNA molecule is 2.66 +/- 0.33 micrometers and its MW is 5.51 +/- 0.68 x 10(6)d, as determined by electron microscope and agarose gel electrophoresis. The lengths of single strands and the double strands of the heteroduplex formed between lambda F2 and linear pCB2 (EcoR1 digested) agree well with the original design for its construction, From the above data, we come to the conclusion that pCB2 we constructed is a new plasmid with cI and/or cro gene expressed in E. coli.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 2","pages":"256-63"},"PeriodicalIF":0.0,"publicationDate":"1981-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17514209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of B22-arginine replacement on the biological activity of insulin. b22精氨酸替代对胰岛素生物活性的影响。
Scientia Sinica Pub Date : 1981-02-01
S Q Zhu, T F Li, D F Cui, Q P Cao, Y S Zhang
{"title":"Effect of B22-arginine replacement on the biological activity of insulin.","authors":"S Q Zhu,&nbsp;T F Li,&nbsp;D F Cui,&nbsp;Q P Cao,&nbsp;Y S Zhang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The semisynthesis of a series of B23-D-Ala deshexapeptide and despentapeptide analogues with B22-arginine replaced are described. The following semisynthetic scheme is used: desnonapeptide insulin pentamethyl ester is prepared from insulin hexamethyl ester through the action of trypsin and carboxypeptidase B, the amino groups are protected with Boc-groups, the protected product is condensed with synthetic peptides, and the protecting groups are removed with trifluoroacetic acid treatment and by saponification. The biological activities of these analogues indicate that the B22-Arg is non-essential and can be replaced by Lys or even Asp without any influence on the biological activity. The activity is reduced to one half when it is replaced by valine or to a very low level when replaced by Gly or D-Arg. The reason for the low activity of guinea pig insulin is discussed.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 2","pages":"264-71"},"PeriodicalIF":0.0,"publicationDate":"1981-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18068630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Double superior venae cavae associated with aberrant subclavian artery--the atavistic and transitional nature of "proximal loss" aortic arch. 双上腔静脉伴锁骨下动脉异常——“近端缺失”主动脉弓的返祖性和移行性
Scientia Sinica Pub Date : 1981-01-01
X C Wan
{"title":"Double superior venae cavae associated with aberrant subclavian artery--the atavistic and transitional nature of \"proximal loss\" aortic arch.","authors":"X C Wan","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A case of double superior venae cavae (Bvc) associated with bilateral azygos veins (Baz), aberrant subclavian artery (Sa) and other rare variations is recorded in a two-year-old Chinese girl with an unknown cause of death. A review of the literature since 1844 indicates that there has been no reported case of a right Sa associated with Bvc + Baz. The primitive arrangement of the thoracic large vessels in this case (Bvc + Baz and CHim type of aortic branches) substantiates the atavistic nature of Sa. The proximal loss pattern (PLdp) of the aortic arch with its associated Bvc + Baz was a primitive transitional link between the vascular arrangement of the Mesozoic reptilian and that of mammals or avians. According to this concept, there should be an occurrence of the PLdp variation (i.e. Sa) in all the mammals and avians and an occurrence of the 1-, 2- or 6-branch type of PLdp in human beings or in other animals.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"24 1","pages":"133-40"},"PeriodicalIF":0.0,"publicationDate":"1981-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18271365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Correlation technique and its application in the His bundle electrocardiogram. 相关技术及其在His束心电图中的应用。
Scientia Sinica Pub Date : 1980-12-01
X S Wang
{"title":"Correlation technique and its application in the His bundle electrocardiogram.","authors":"X S Wang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In literature, the HBE has been displayed by application of the averaging method. In this paper, correlation analysis technique was used and the body-surface HBE was displayed in a special-purpose electronic computer. The correlation coefficients of the P-A, A-H, H-V intervals and the H-wave width of both methods are almost equivalent and one can be substituted by the other. Compared with the averaging method, the S/N ratio of the correlation method is greater and the residual noise is nearly absent. Furthermore, the effects of the integrating time T and delay time delta tau on the S/N ratio, the measuring resolution and the analytical time have been studied. Correlation analysis technique is a method based on the cybernetic and information theory. With this technique, by using correlation function, the dependence (auto-correlation function) of the value at one instant upon that of the other during the same random process, or the interdependence between sets of data from 2 random processes can be described. Up to the present, there has been no report on the activities of the ventricular conductive system with the S/N ratio smaller than 1, detected on the body surface by correlation analysis technique[1 - 3]. However, using this technique, the author successfully detected the body surface HBE with a special-purpose mini-computer in 1977.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"23 12","pages":"1599-607"},"PeriodicalIF":0.0,"publicationDate":"1980-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18295219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Restriction endonucleases from three strains of Haemophilus influenzae. 三株流感嗜血杆菌的限制性内切酶。
Scientia Sinica Pub Date : 1980-11-01
S X Shen, Q L Li, P F Yan, B Zhou, S Y Ye, Y Y Lu, D B Wang
{"title":"Restriction endonucleases from three strains of Haemophilus influenzae.","authors":"S X Shen,&nbsp;Q L Li,&nbsp;P F Yan,&nbsp;B Zhou,&nbsp;S Y Ye,&nbsp;Y Y Lu,&nbsp;D B Wang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The restriction endonucleases, Hin P1 I1), Hin S1 I and Hin S2 I are isolated from three strains of Haemophilus influenzae respectively. By polymin P treatment, ammonium sulphate, precipitation and column chromatography on phosphocellulose and on heparin-Sepharose Hin P1 I is partially purified. No contaminating deoxyribonuclease activities have been detected in this purified enzyme preparation. The fact that the digestion patterns of Hin P2 I and Hha I on phage lambda, plasmids ColE1 an pBR 322 DNAs are identical that they are isoschizomers but theri splitting sites are different. The banding patterns of Hin S1 I and Hin S2 I are also the same as that of Hha I.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"23 11","pages":"1435-42"},"PeriodicalIF":0.0,"publicationDate":"1980-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17326106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Preparations and properties of crystalline porcine and bovine [Trp]B1 insulins. 猪和牛晶体[Trp]B1胰岛素的制备及性能研究。
Scientia Sinica Pub Date : 1980-11-01 DOI: 10.1360/YA1980-23-11-1443
K. Lei, Z. Z. Wang, B. Dong, B. Ru, S. Zhu
{"title":"Preparations and properties of crystalline porcine and bovine [Trp]B1 insulins.","authors":"K. Lei, Z. Z. Wang, B. Dong, B. Ru, S. Zhu","doi":"10.1360/YA1980-23-11-1443","DOIUrl":"https://doi.org/10.1360/YA1980-23-11-1443","url":null,"abstract":"[Trp]B1 analogs to porcine and bovine insulins have been obtained through selective reaction with Msc-ONSu, and followed by Edman degradation, condensation with Msc-Trp-ONp and deprotection. Through cellulose acetate electrophoresis, amino acid composition analysis, UV absorption spectrum and N-terminal analysis, it has been proved that the products are of purified [Trp]B1 insulin. Mouse convulsion assay shows that the biological activities of porcine and bovine [Trp]B1 insulins are 18 i.u./mg and 17 i.u./mg respectively, corresponding to about 70% of the original activity of native porcine insulin. Their structural details are under investigation in our laboratory.","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"14 1","pages":"1443-52"},"PeriodicalIF":0.0,"publicationDate":"1980-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77094364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
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