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WANG JC 《The Journal of general physiology》1948,31(3):259-268
1. Experiments were performed on six dogs to determine the rate of penetration of Cl(33) and Na(24) across the blood-aqueous humor and blood-cerebrospinal fluid barriers after intravenous injection of the radioactive ions. The radioactivity measurements were made with an immersion type of Geiger-Müller counter. 2. The concentrations of the labelled ions in the anterior chamber and the cisterna magna increase slowly to approach that of plasma. The rate of penetration k is calculated from a simple exponential equation with the half-value interval t(0.5) or the time required for the labelled-ion concentration in the fluid to reach 50 per cent of that of plasma. The average t(0.5) for Cl(38) and Na(24) in aqueous humor are 34.3 +/- 9 and 27.3 +/- 9 minutes, respectively, while those for cerebrospinal fluid are 90 +/- 6 and 95 +/- 6 minutes, respectively. 3. A study of the radioactivity in plasma was made to determine the per cent remaining after a steady state was reached. By means of this determination the sodium and chloride space was calculated to be 33 +/- 5 per cent. 相似文献
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Periss0dactyla0wen,laseTaPiroideaGill,lgy2?tophiaiedaeMathedthenger,1925(Radhay,l%5)Ampeqhu!~gco'etsp'nov'TypeAfragInentaryrightmaxillawithcomPleteP2-MlandanteriorpartofM2twvlo7o2)'~andhothenCountyMine,2kmeastofWutUVillageofChangleCounty,Shandong;Eariyhee,WutUFonnahon'Inagn0dsApdrihveandmedium-edtapiroid'UPpercheekdrilow-crownedandmoderatey1ophodont,withdishnCtcuSPs;MlAnconeequalt0paraconeinfor;parastylerelativefysmall,anddosetoparacone;labialandlingUalcusPsinclinedt0ndd-dleakisof… 相似文献
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<正>The prominent role Ca2+ion plays as a major small biological messenger is fascinating.There are many physiologically important ions,such as Na+,K+,H+,Cl?,Ca2+,Mg2+,Fe3+,and PO43?that participate in cell signaling.Among them,monovalent ions primarily contribute to rapid electrical signaling,while multivalent ions generally act as a co-factor for chemical reactions by associating with the host molecule through electrostatic or covalent interactions.Ca2+plays both roles.Its transmembrane influx supports the plateau phase of cardiac action potential and helps set the speed of pacemaker potential.Inside the cell,Ca2+switches 相似文献
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Ethanol disrupts the formation of hypochord and dorsal aorta during the development of embryonic zebrafish 总被引:2,自引:0,他引:2
QIAN Linxi WANG Yuexiang JIANG Qiu ZHONG Tao & SONG Houyan Key Laboratory of Molecular Medicine Ministry of Education Shanghai Medical School of Fudan University Shanghai China 《中国科学:生命科学英文版》2005,48(6):608-615
It has been demonstrated that maternal drinking during pregnancy had serious adverse effects on the health of the newborns. Fetal alcohol syndrome (FAS) is the most important developmental abnormality caused by maternal alcohol abuse during pregnancy. Clinically, it is characterized by head and facial ab-normalities, cardiovascular malformation, and perma-nent nervous system damage[1,2]. A lot of experimental models have been developed to study the ethanol’s effects on embryonic development,… 相似文献
7.
Construction of a cucumber genetic linkage map with SRAP markers and location of the genes for lateral branch traits 总被引:7,自引:0,他引:7
WANG Gang * PAN Junsong * LI Xiaozun HE Huanle WU Aizhong & CAI Run Agriculture Biology School of Shanghai Jiaotong University Shanghai China 《中国科学:生命科学英文版》2005,48(3):213-220
Cucumber (Cucumis sativus L. 2n = 2x = 14), thatbelongs to Cucurbitaceae family, is one of majorvegetables with a planting area second to that of to-mato in the world[1]. Due to its economical importanceplant breeders and geneticists have paid much atten-tion to the genetic study on this important vegetablecrop, but the research progress in cucumber is muchless than that in tomato. In 1990, Pierce[2] reviewed allthe reported genes of cucumber that had been geneti-cally analyzed since the 1930… 相似文献
8.
The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage 总被引:1,自引:0,他引:1
TAN Xin PENG An WANG Yongchao & TANG Zuoqing . School of Life Sciences Technology Beijing Institute of Technology Beijing China . College of Life Sciences Beijing Normal University Beijing China . College of Basic Medicine Capital University of Medical Sciences Beijing China 《中国科学:生命科学英文版》2005,48(3):287-294
Many studies have shown that the ubiq-uitin-proteasome pathway (UPP) for the degradation of short-lived proteins plays a key role in regulating cell cycle progression[1—3]. At least two distinct prote-olytic pathways are required for cell cycle process. The first pathway promotes transition from G1 to S phase, and the second initiates the onset of anaphase and exit from mitosis. The inhibition of UPP will re-sult in the blockage of cell cycle process. The knowl-edge of the role of UPP in… 相似文献
9.
Gene cloning and expression of cadherin in midgut of Helicoverpa armigera and its Cry1A binding region 总被引:1,自引:0,他引:1
WANG Guirong WU Kongming LIANG Gemei & GUO Yuyuan State Key Laboratory of Plant Disease Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Be China 《中国科学:生命科学英文版》2005,48(4):346-356
Bacillus thuringiensis (Bt), a Gram-positive bacte-rium, produces insecticidal crystal proteins during sporulation. Bt has been used as biopesticides to con-trol a number of insect pests from Lepidoptera, Dip-tera and Hymenoptera and also has become so far the leading gene sources of transgenic plants resistant toinsect pests[1,2]. In China, the use of Bt cotton began in 1997 in Hebei, Shandong and Henan provinces, etc. and rapidly increased to more than 2 million ha in 2002, which is effe… 相似文献
10.
Study of the tolerance of Hippochaete ramosissimum to Cu stress 总被引:1,自引:0,他引:1
LIU Dengyi LI Ying CHU Ling WANG Guanglin & WANG Lilong Biodiversity Research Center Anhui Normal University Wuhu China The Provincial Key Laboratory of Conservation Exploitation of Biological Resources in Anhui Wuhu China 《中国科学:生命科学英文版》2005,48(Z1)
We investigated the tolerance of Hippochaete ramosissimum and the changes in physiological metabolism following exposure to copper using pot experiments and analyzing plant physiology and biochemistry. The results showed that Cu tolerance in Hippochaete ramosissimum varied significantly between different populations; the tolerance of plants living in Cu polluted areas for extended periods of time exceeded that of plants living in unpolluted areas. SOD and POD activities in highly Cu tolerant plants increased noticeably following exposure to Cu. This indicates that maintaining and increasing the two kinds of protective enzyme activities are the primary foundations of plant tolerance. However, no change in CAT activity was demonstrated following Cu exposure. In summary, there existed considerable differences in physiological metabolism between different populations of Hippochaete ramosissimum following exposure to Cu. 相似文献