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Studies on the mechanism of insulin action. IV. The isolation and determination of a low insulin receptor activity. 胰岛素作用机制的研究。四、低胰岛素受体活性的分离和测定。
Scientia Sinica Pub Date : 1977-11-01
{"title":"Studies on the mechanism of insulin action. IV. The isolation and determination of a low insulin receptor activity.","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>After passing the membrane protein dissolved in 1% DOC over a Sepharose 4B column, a peak with insulin receptor binding activity has been shown in the void volumn. After treating this single peak fraction with 6M guanidine HCl and again passing over a Sepharose 4B column preequilibrated with guanidine HCl, four absorbing peaks at 280 nM have been observed. In addition to the first peak representing the void volume, the 4th absorbing peak has been found to display an obvious binding activity as well. This low molecular biologically active unit has also been demonstrated by means of gel electrophoresis. Its molecular weight has been determined with Sepharose 6B to be about 50,000 daltons.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 6","pages":"794-802"},"PeriodicalIF":0.0,"publicationDate":"1977-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11809791","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
Genetic analysis of the nitrogen fixation system in Klebsiella pneumoniae. 肺炎克雷伯菌固氮系统的遗传分析。
Scientia Sinica Pub Date : 1977-11-01
C T Hsueh, J C Chin, Y Y Yu, H C Chen, W C Li, M C Shen, C Y Chiang, S C Shen
{"title":"Genetic analysis of the nitrogen fixation system in Klebsiella pneumoniae.","authors":"C T Hsueh,&nbsp;J C Chin,&nbsp;Y Y Yu,&nbsp;H C Chen,&nbsp;W C Li,&nbsp;M C Shen,&nbsp;C Y Chiang,&nbsp;S C Shen","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Fine structure mapping of nif mutations of Klebsiella pneumoniae was accomplished by means of Pl-transductional crosses and the plasmid R144 drd mediated conjugations. The physical distance between nif mutations based on the percentage of co-transduction with hisD of the nif mutations was estimated. The maximal distance between two mutations was calculated about 3 Kb, and the average distance between different nif mutations was about 1 to 2 Kb. So no \"silent region\" was shown within the nif cluster nearby the histidine operon. Several hisD-unlinked nif mutants were isolated and investigated genetically and biochemically. They all differed from the glutamineless mutants, one of these mutants was tentatively assigned as a sort of N-assimilation mutant with little activity of glutamate synthetase. It differed from the known N-assimilation mutants in its absence of nitrogenase activity. Since the wild type hisD-linked nif genes carried by the plasmid RP4 failed to complement the defects of the hisD-unlinked nif genes in the recipient cells but they were effective to facilitate E. coli in acquiring the ability to fix nitrogen, which indicates that the hisD-unlinked nif genes necessary for the functioning of the hisD-linked nif genes are present in E. coli.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 6","pages":"807-17"},"PeriodicalIF":0.0,"publicationDate":"1977-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11247859","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
Genetic manipulation in higher organisms. I. Goldfish ova as materials of operation, mRNA mediated alteration of the liver specific isozymes. 高等生物的基因操纵。1 .金鱼卵作为手术材料，mRNA介导肝脏特异性同工酶的改变。
Scientia Sinica Pub Date : 1977-11-01
M C Niu, T C Tung
{"title":"Genetic manipulation in higher organisms. I. Goldfish ova as materials of operation, mRNA mediated alteration of the liver specific isozymes.","authors":"M C Niu,&nbsp;T C Tung","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Both crucian and carp egg-mRNAs were found to mediate the transformation of goldfish tail from the double (veil-shaped) to the single (fork-shaped). Livers of these single tailed goldfish were tested for genetic change using lactate dehydrogenase isozymes (LDH) as marker. Electrophoresis of liver extracts on starch gel showed that the liver specific LDH-C4 isozymes of both the egg-mRNA and liver-mRNA injected goldfish resembled the control goldfish except an additional intermediate band. The migration distance of this new band matched the third band of the hybrids (carp X goldfish). These findings lead to the conclusion that carp egg-mRNA contains a fraction partly responsible for liver development. Rat liver was found possessing the cathodally migrating C4 isozymes. Injection of rat liver-mRNA into goldfish eggs resulted in the intensification of the liver specific C4 isozymes. It appears therefore that the input informational molecules (liver-mRNA) and the output molecular products (liver C4 isozymes) are causally related. This causal relationship would pave the way for genetic manipulation in higher organisms.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 6","pages":"803-6"},"PeriodicalIF":0.0,"publicationDate":"1977-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11487669","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
Preliminary study on the age of Yuanmou man by palaeomagnetic technique. 用古地磁技术对元谋人年龄的初步研究。
Scientia Sinica Pub Date : 1977-09-01
L Pu, C Fang, M Hsing-hua, P Ching-yu, H Li-Sheng, C Shih-chiang
{"title":"Preliminary study on the age of Yuanmou man by palaeomagnetic technique.","authors":"L Pu,&nbsp;C Fang,&nbsp;M Hsing-hua,&nbsp;P Ching-yu,&nbsp;H Li-Sheng,&nbsp;C Shih-chiang","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Since the discovery of the fossil teeth of Yuanmou man (Homo erectus yuanmouensis) on May 1, 1965 from Yuanmou county, Yunnan Province, the Institute of Geomechanics, relying on the local poor and lower-middle peasants and co-operating with other units concerned, has been conducting intensive researches on the fossil man-bearing strata as well as Quaternary glaciation. Palaeomagnetic technique lately used in the study has for the first time shown that the Yuanmou man appeared around 1.7 million years ago, earlier than both Peking man and Lantien man. Hence the age formerly assigned to the earliest fossil man in China has to be increased by more than a million years. Furthermore, as the age of Yuanmou formation is fixed at 1.5--3.1 million years, the length of Quaternary has to be extended by more than two million years. Of special interest is that under the Yuanmou formation there occur glacial traces which prove beyond doubt the existence of glaciation over 3 million years ago. This is a new discovery in the Quaternary history of China, and provides a new approach to the future study of this period.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 5","pages":"645-64"},"PeriodicalIF":0.0,"publicationDate":"1977-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11549219","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
Palaeocene vertebrate horizons and mammalian faunas of South China. 华南古新世脊椎动物层位和哺乳动物群。
Scientia Sinica Pub Date : 1977-09-01
{"title":"Palaeocene vertebrate horizons and mammalian faunas of South China.","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In the past ten years or so a large amount of Palaeocene mammals (more than one hundred species belonging to 11 orders, 17 families and 52 genera) were known from five \"redbed\" basins of South China. These new finds are very important to a correct understanding of the evolution and distribution of mammals at the beginning of Tertiary in Asia. This paper includes three parts: (1) mammal-bearing Palaeocene of South China, (2) ages and correlation of the Palaecocene faunas of South China, (3) characteristics of the Palaeocene faunas of South China. The known Palaeocene mammals of South China can be grouped into two assemblages: the Lower Assemblage of the Early-Middle Palaeocene age, and the Upper Assemblage of the Late Palaeocene age. The endemic Asian genus, Bemalambda, is a form characteristic of the Lower Assemblage, and another endemic Asian form, Archaeolambda, is diagnostic of the upper. Some inferences on the origin, distribution and dispersal routes of certain Palaeocene mammalian groups are also discussed briefly in the third part.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 5","pages":"665-78"},"PeriodicalIF":0.0,"publicationDate":"1977-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11550316","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
A new highly effective ovulating agent for fish reproduction. Practical application of LH-RH analogue for the induction of spawning of farm fishes. 一种新型高效的鱼类生殖排卵剂。rh - rh模拟物在诱导养殖鱼类产卵中的实际应用。
Scientia Sinica Pub Date : 1977-07-01
{"title":"A new highly effective ovulating agent for fish reproduction. Practical application of LH-RH analogue for the induction of spawning of farm fishes.","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The synthetic analogue of the nonapeptide LH-RH has been found to be highly effective in the induction of spawning of farm fishes (the grass carp, the silver carp, the spotted silver carp, and the black carp.) Its biological activity is many times higher than that of the synthetic decapeptide or natural releasing hormone. Out of a total number of 500 mature fishes treated with the nonapeptide alone and/or combined with a minimum amount of fish pituitary, 396 of them spawned--with an over-all spawning rate of 78%. As far as we know, this is probably the most effective ovulating agent or hormone now available for fishes. This finding is of paramount importance in pisciculture for large-scale production of fry. The recommended dosages for the following farm fishes are: the grass carp--1-10 microgram/kg b.w.; the silver carp--3 microgram or more/kg b.w. in divided doses; the spotted silver carp--1.4 microgram or more/kg b.w.; and the black carp--10 microgram/kg b.w. For the latter species, the efficacy of the peptide could be improved by a concurrent administration of 0.5-2 mg of the pituitary gland. The significance of this work in piscicultural practice and the mechanism of hormonal action are briefly discussed.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 4","pages":"469-74"},"PeriodicalIF":0.0,"publicationDate":"1977-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"11546445","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
The inhibition effect and the mode of action of electro-acupuncture upon discharges from the pain-sensitive cells in spinal trigeminal nucleus. 电针对三叉神经脊髓核痛觉细胞放电的抑制作用及作用方式。
Scientia Sinica Pub Date : 1977-07-01
{"title":"The inhibition effect and the mode of action of electro-acupuncture upon discharges from the pain-sensitive cells in spinal trigeminal nucleus.","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Acupuncture, one of the important branches of Chinese traditional medicine, is unique in its capability of treating many kinds of diseases. Owing to its pain-relieving action, it has been much used for the treatment of pains since ancient times and is used recently for surgical operations, major or minor, to replace drug anaesthetization. As to the mechanism of its action, there is much to be learned and this is the problem that we are now tackling.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 4","pages":"485-501"},"PeriodicalIF":0.0,"publicationDate":"1977-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12103434","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 stimulation of bulbar reticular formation on long latency discharges in the region of nucleus centralis lateralis of thalamus. 刺激球网状结构对丘脑外侧中央核区域长潜伏期放电的影响。
Scientia Sinica Pub Date : 1977-07-01
K F Shen, S F Ho
{"title":"Effect of stimulation of bulbar reticular formation on long latency discharges in the region of nucleus centralis lateralis of thalamus.","authors":"K F Shen,&nbsp;S F Ho","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Electrical stimulation of medial medullary reticular formation of rabbits was found to have marked inhibitory effect on nociceptive discharges of neurons in the region of centrolateral nucleus of thalamus. Among the 32 nociceptive units tested, 15 showed the inhibitory effect, 3 the facilitatory, and 14 no effect. Comparison between the effect of direct stimulation of medial medullary reticular formation and that of the electric needling on the same neurons revealed a general resemblance of the two in many respects. These findings suggest that the nucleus reticularis gigantocellularis in medial bulbar reticular formation may serve as an important relay station in the transmission of the analgesic effect of acupuncture.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 4","pages":"475-84"},"PeriodicalIF":0.0,"publicationDate":"1977-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12103433","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
The metabolic fate of daidzein. 大豆苷元的代谢命运。
Scientia Sinica Pub Date : 1977-07-01
T L Yueh, H Y Chu
{"title":"The metabolic fate of daidzein.","authors":"T L Yueh,&nbsp;H Y Chu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>A method using thin layer chromatography and ultraviolet spectrophotometry for isolation and quantitative determination of daidzein from biological specimens was developed. This method was found to be sensitive and specific and was used in this study for the observation of the metabolic fate of daidzein in animals and human bodies.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 4","pages":"513-21"},"PeriodicalIF":0.0,"publicationDate":"1977-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12103436","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
Regeneration of plants from tobacco protoplasts and some factors affecting the plant differentiation. 烟草原生质体的植物再生及影响植物分化的一些因素。
Scientia Sinica Pub Date : 1977-07-01
C K Tsai, Y C Ch'ien, Y L Chou, S H Wu
{"title":"Regeneration of plants from tobacco protoplasts and some factors affecting the plant differentiation.","authors":"C K Tsai, Y C Ch'ien, Y L Chou, S H Wu","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Protoplasts were isolated from the cell suspension culture derived from leaf and stem calli of tobacco (Nicotiana tabacum cv. Ko Hsin No. 1) haploid pollen-plants. After 12 hr in the liquid culture medium, the protoplasts became oval-shaped, and produced a new cell wall. The first division of the newly formed cells was completed after 24 hr in culture. After 4 weeks in culture, the yellowish calli reached 1 mm in size were then transferred to an auxophyton. 18 days later, the calli became 3-4 mm in size. After the calli were transferred to a differentiation culture medium, shoots and roots soon turned up. Regeneration of whole plants was obtained thereafter. The division and differentiation of regenerated cells were affected not only by the calli originated from different organs and their, age, but also by the basic components of the differentiation culture medium and the type of cytokinin used.</p>","PeriodicalId":21694,"journal":{"name":"Scientia Sinica","volume":"20 4","pages":"458-68"},"PeriodicalIF":0.0,"publicationDate":"1977-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12103431","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
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