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21.
Yoshiyasu Fukuyama Tsuneo Sato Iwao Miura Yoshinori Asakawa Tsunematsu Takemoto 《Phytochemistry》1983,22(2):549-552
From the methanol extract of the root of Polygonum hydropiper, a novel coumaryl glycoside hydropiperoside was isolated together with anthraquinone, ellagic acid 3,3′-di-O-methyl ether, gallic acid, two quercetin glycosides and an unidentified aromatic δ-lactone possessing antifertility activity. The structure of hydropiperoside was established as β-d-(1,3,6-tri-p-coumaryl)-fructofuranosyl-α-d-glucopyranoside by combination of extensive 1H NMR and 13C NMR spectra, and the FD/MS spectrum. 相似文献
22.
Pairs of neurons were differentially stained by intracellular injection of the divalent cations, nickel and cobalt. Pairs of neuronal tracts could be similarly labelled following immersion of their axon bundles in the markers described. Use of nickel and a 4 : 6 mixture of cobalt and nickel according to the protocols presented here revealed the morphology of cricket neuron processes as thin as 1 μm in diameter and yielded a favourable contrast between the cells marked, as well as with respect to the background of unstained tissue. 相似文献
23.
T Kurokawa M Seno R Sasada Y Ono H Onda K Igarashi M Kikuchi Y Sugino T Honjo 《Nucleic acids research》1983,11(10):3077-3085
Using the cDNA of human epsilon chain, three expression plasmids that code directly the constant portion of the epsilon chain (C epsilon 1-C epsilon 4, C epsilon 2-C epsilon 4 and C epsilon 3-C epsilon 4 domains) were constructed. These epsilon chain peptides were synthesized in E. coli under the control of the trp promoter-operator. The bacterially produced peptides have the antigenicity of human epsilon chain and gave the molecular weights equal to the values calculated from the amino acid sequence of the constructed plasmids. 相似文献
24.
Molecular cloning and nucleotide sequencing of human immunoglobulin epsilon chain cDNA. 总被引:4,自引:1,他引:3
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M Seno T Kurokawa Y Ono H Onda R Sasada K Igarashi M Kikuchi Y Sugino Y Nishida T Honjo 《Nucleic acids research》1983,11(3):719-726
DNA complementary to mRNA of human immunoglobulin E heavy chain (epsilon chain) isolated and purified from U266 cells has been synthesized and inserted into the PstI site of pBR322 by G-C tailing. This recombinant plasmid was used to transform E. coli chi 1776 to screen 1445 tetracycline resistant colonies. Nine clones (pGETI - 9) containing cDNA coding for the human epsilon chain were recognized by colony hybridization and Southern blotting analysis with a nick-translated human IgE genome fragment. The nucleotide sequence of the longest cDNA contained in pGET2 was determined. The results indicate that the sequence of 1657 nucleotides codes for 494 amino acids covering a part of the variable region and all of the constant region of the human epsilon chain. Most of the amino acid sequence deduced from the nucleotide sequence is in substantial agreement with that reported. Furthermore a termination codon after the -COOH terminal amino acid marks the beginning of a 3' untranslated region of 125 nucleotides with a poly A tail. Taking this into account, the structure of the human epsilon chain mRNA, except a part of the 5' end, is conserved fairly well in the cDNA insert in pGET2. 相似文献
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Summary Spermatozoa from fertile and infertile human ejaculates were observed under the scanning electron microscope. A parallel study of sections was performed by transmission electron microscope.The normal head shows under the scanning electron microscope vesicular elevations in the region of the acrosome and a smooth and rigid appearance corresponding to the postnuclear cap whose occurrence is confirmed under the transmission electron microscope. Immediately anterior to this cap a shallow furrow transverses the head. Duplicated, unusually large or small and deformed heads are found under the scanning electron microscope. Most of these abnormal heads show no surface structure suggesting an acrosome.The neck and middle piece are occasionally, though frequently in abnormal spermatozoa, covered by a cytoplasmic droplet. Otherwise, the mitochondrial sheath is recognized under the scanning electron microscope as a beaded thickening in the middle piece. The lack of mitochondria is manifested by a smooth middle piece thinner than the principal portion. Transmission electron microscopy of sections reveals various types of anomalies in the number of cores, core filaments and mitochondria embedded in the cytoplasmic droplets.Abnormalities in the principal portion of the tail such as duplication, unusual thickness and length are shown under the scanning electron microscope.The investigation indicates that scanning electron microscopy is suited for the clinical as well as cytological examination of human ejaculate spermatozoa. 相似文献
28.
Summary Using the electron microscopy and electron microscopic histochemistry the authors studied the lung alveolar epithelial cell of normal young mice.Type II cell of the alveolar epithelium has characteristically numerous osmiophilic lamellar bodies. The lamellar boies are formed in the cytoplasmic vesicle, and never originate from the mitochondrion. These bodies have abundant acid phosphatase activity in their limiting membrane therefore it is considered to be lysosomal origin, but the mitochondria have no such enzyme activity.The body which is newly formed in the cytoplasmic vesicle grows up to the large lamellar body as a result of an accumulation of the fibrous dense substance, migrates to the free margin of the type II cell of alveolar epithelium, and then is discharged into the alveolar lumen as a merocrine type secretion.Acknowledgement is given to Professor Dr. Y. Sano and Professor Dr. H. Fujita, Department of Anatomy, and Assistant Professor Dr. S. Fujita, Department of Pathology, for their kind advice and criticism. 相似文献
29.
Control of IL-2 receptor-alpha expression by IL-1, tumor necrosis factor, and IL-2. Complex regulation via elements in the 5' flanking region 总被引:2,自引:0,他引:2
G Plaetinck M C Combe P Corthésy P Sperisen H Kanamori T Honjo M Nabholz 《Journal of immunology (Baltimore, Md. : 1950)》1990,145(10):3340-3347
30.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds 总被引:7,自引:0,他引:7
Masayuki Yamamoto Shin-ichiro Takai Tetsuro Miki Kazuyoshi Motomura Makoto Okazaki Isamu Nishisho Hideo Tateishi Akira Miyauchi Tasuku Honjo A. J. Pakstis Takesada Mori 《Human genetics》1989,81(3):287-288
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds. 相似文献