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11.
Axial changes in the nemertean egg and embryo during development and its phylogenetic significance 总被引:4,自引:0,他引:4
On the basis of the axial relationship between the larva and adult, it is possible to divide the larvae of the members of the Heteronemertea and a species of the Palaeonemertea into five types, forming a sequential series in which the adult axis of each advances by an angle of 45° from that immediately preceding it. Phylogenetic consideration of the Nemertea has been undertaken in the light of evidence provided by the axiality of the embryos and the developmental data hitherto recorded. 相似文献
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柑桔果实中柠檬苦素类化合物的研究现状与展望 总被引:17,自引:0,他引:17
柠檬苦素类似物(limonoid)是三萜类的植物次生代谢产物,主要存在于芸香科和楝科植物中。柠檬苦素(limonin)及其类似物存在于柑桔属(Citrus)的多种植物中。至今已从柑桔属植物中分离出36种柠檬苦素类似物及17种柠檬苦素类似物配糖体。柑桔中苦味原因之一为柠檬苦素类似物。作为其代表具有强烈苦味的柠檬苦素和诺米林如果在柑桔果汁中含量超过6mg/L,那么这种柑桔用于饮食业已不适合[1]。近年来,笔者对柑桔果实中的柠檬苦素类似物的生理变化及生物合成作过系统研究[1~9],并提出将柠檬苦素类似… 相似文献
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Takeshi K. Watanabe Toyomasa Katagiri Mikio Suzuki Fumio Shimizu Tsutomu Fujiwara Naohide Kanemoto Yusuke Nakamura Yoshikatsu Hirai Hiroumi Maekawa Ei-ichi Takahashi 《Genomics》1996,38(3):273
From a human fetal-brain cDNA library we isolated two novel genes encoding peptides containing six EGF-like repeats. Both showed significant homologies with nel, a gene strongly expressed in neural tissues of chicken. The cDNAs, designated NELL1 (nel-like, type 1) and NELL2 (nel-like, type 2), contained open reading frames encoding 810 and 816 amino acids, respectively. NELL2 is strongly expressed in brain of adult and fetus but only weakly in fetal kidney. NELL1 and NELL2 were mapped by FISH to chromosomal bands 11p15.1–p15.2 and 12q13.11–q13.12, respectively. 相似文献
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In order to automate measurements of cell concentration and viability in a suspended animal cell culture, we have developed anin situ microscopic image analysis system with an effective cell recognition algorithm. With a small amount of sample, this system can measure the cell density rapidly and aseptically. In addition, it can measure a cell size histogram including cell debris small particle distribution. These small particles have been found to be related to the viability of the mouse-mouse hybridoma STK1 cell line. By using cell debris small particle density as an indicator of cell viability, the developed system provides non-destructive viability monitoring without trypan blue staining. 相似文献
19.
William D. Figg Herman J.C. Yeh Alain Thibault James M. Pluda Fumio Itoh Robert Yarchoan Michael R. Cooper 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,652(2)
This paper describes a reversed-phase, high-performance liquid chromatographic (HPLC) method for the isolation, detection, and quantification of TNP-470 (I) and one of its active metabolites, AGM-1883 (II), from plasma. These compounds are initially extracted from plasma with an organic solvent and then separated from one another on a C18 column. Those fractions eluting from the C18 column and containing either I or II are then derivatized through their epoxide moieties with sodium 8-quinolinethiolate (SQT). This derivatization produces fluorescent species that are isolated and quantified by a second reversed-phase HPLC analysis. The assay yields a lower limit of reliable quantification of 2.5 ng/ml and is linear to a concentration at least as high as 160 ng/ml. The inter-assay percent coefficient of variation is less than 18%. 相似文献
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Fumio Yamazaki Ryoko Sone Nobuharu Fujii Haruo Ikegami 《International journal of biometeorology》1993,37(4):212-217
Based on the hypothesis that the relation between sweating rate and body temperature should be different during exercise and rest after exercise, we compared the sweating response during exercise and recovery at a similar body temperature. Healthy male subjects performed submaximal exercise (Experiment 1) and maximal exercise (Experiment 2) in a room at 27° C and 35% relative humidity. During exercise and recovery of 20 min after exercise, esophageal temperature (Tes), mean skin temperature, mean body temperature (
), chest sweating rate (
), and the frequency of sweat expulsion (F
SW) were measured. In both experiments,
andF
SW were clearly higher during exercise than recovery at a similar body temperature (Tes,
).
was similar during exercise and recovery, or a little less during the former, at a similarF
SW. It is concluded that the sweating rate during exercise is greater than that during recovery at the same body temperature, due to greater central sudomotor activity during exercise. The difference between the two values is thought to be related to non-thermal factors and the rate of change in mean skin temperature. 相似文献