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51.
Isogai Akira; Takayama Seiji; Shiozawa Hideyuki; Tsukamoto Chise; Kanbara Takeshi; Hinata Kokichi; Okazaki Keiichi; Suzuki Akinori 《Plant & cell physiology》1988,29(8):1331-1336
S-Glycoproteins (S-locus-specific glycoproteins) in Brassicaspecies are present only in stigmas and thought to play an importantrole in self-incompatibility system. The stigma extract containsalso several other glycoproteins reacting with the antiserumto S-glycoproteins, among which some glycoproteins from S8S8-and S9S9-homozygotes have the same pI value. Both of the glycoproteinswhich were tentatively termed NS8- and NS8S9-glycoproteins,respectively, were isolated and analyzed. Those were revealedto be identical. Its amino acid sequence was homologous withthe S-glycoproteins in Brassica species. The NS-glycoproteinswere expressed at the same time and only in stigma as S-glycoproteins. (Received July 19, 1988; Accepted September 7, 1988) 相似文献
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The leaf ultrastructure of NADP-malic enzyme type C4 species possessing different anatomical features in the Cyperaceae was examined: types were the Rhynchosporoid type, a normal
Kranz type in which mesophyll cells are adjacent to Kranz cells, and Fimbristyloid and Chlorocyperoid types, unusual Kranz
types in which nonchlorophyllous mestome sheath intervenes between the two types of green cells. They show structural characteristics
basically similar to the NADP-malic enzyme group of C4 grasses, that is, centrifugally located chloroplasts with reduced grana and no increase of mitochondrial frequency in the
Kranz cells. However, the Kranz cell chloroplasts of the Fimbristyloid and Chlorocyperoid types exhibit convoluted thylakoid
systems and a trend of extensive development of peripheral reticulum, although those of the Rhynchosporoid type do not possess
such particular membrane systems. The suberized lamella, probably a barrier for CO2 diffusion, is present in the Kranz cell walls of the Rhynchosporoid type and in the mestome sheath cell walls of the other
two types, and tightly surrounds the Kranz cells (sheaths) that are the sites of the decarboxylation of C4 acids. These ultrastructural features are discussed in relation to C4 photosynthetic function. 相似文献
55.
Previous studies have demonstrated that NMDA receptor antagonists and protein kinase C inhibitors induced marked memory impairment in rats, but that peripherally administered cerulein (CER) prevented these effects. In the present study, the effect of subcutaneously administered CER on amnesia induced by protein synthesis inhibitors was examined in passive and active avoidance responses and in the Morris water maze test. Intraperitoneal injection of the inhibitors produced marked memory impairment, but the effect was abolished by combined administration with CER. The effective dose of subcutaneously injected CER was, on a molar basis, three thousand- and six thousandfold less than the dose of anisomycin, and two hundred eighty- and three thousandfold less than the dose of puromycin in the passive and active avoidance response experiments, respectively. Similarly, in the Morris water maze test, behavioral disturbances produced by the protein synthesis inhibitors were abolished by CER. These results indicate the effectiveness of CER in preventing memory impairment induced by protein synthesis inhibitors. 相似文献
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57.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
58.
The involvement of specific opiate receptors in the suppression of LH release during acute fasting in ovariectomized estradiol-treated rats was examined by intracerebroventricular (i.c.v.) administration of opiate receptor antagonists that exert a specificity directed mainly, although not absolutely, towards the delta-, kappa- or mu-opiate receptors. Fasting for 48 h significantly decreased mean plasma LH levels in estradiol-treated animals by increasing sensitivity to the negative feedback effect of estradiol. Injecting i.c.v. the mu-opiate receptor antagonist naloxone (10 or 100 nmol in 2 microliters of saline) blocked the inhibitory effect of fasting on pulsatile LH release and reinstated LH pulses. On the other hand, i.c.v. administration of the same dosages of a delta-opiate receptor antagonist ICI 174,864 or a kappa-opiate receptor antagonist WIN 44441-3 did not have any effect. These results suggest that the increased sensitivity of the LH-releasing mechanism to the negative feedback effect of estradiol during fasting involves the endogenous opioids mainly through the selective activation of the mu-opiate receptors. 相似文献
59.
Identification of the region including the epitope for a monoclonal antibody which can neutralize human parvovirus B19.
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H Sato J Hirata M Furukawa N Kuroda H Shiraki Y Maeda K Okochi 《Journal of virology》1991,65(4):1667-1672
In this study, we identified a region in the human parvovirus structural protein which involves the neutralization of the virus by a monoclonal antibody and site-specific synthetic peptides. A newly established monoclonal antibody reacted with both viral capsid proteins VP1 and VP2. The epitope was found in six strains of independently isolated human parvovirus B19. The monoclonal antibody could protect colony-forming unit erythroid in human bone marrow cell culture from injury by the virus. The monoclonal antibody reacted with only 1 of 12 peptides that were synthesized according to a predicted amino acid sequence based on nucleotide sequences of the coding region for the structural protein of B19 virus. The sequence recognized by the antibody was a site corresponding to amino acids 328 to 344 from the amino-terminal portion of VP2. This evidence suggests that the epitope of the viral capsid protein is located on the surface of the virus and may be recognized by virus-neutralizing antibodies. 相似文献
60.
N Nakakita K Maeda H Ojimi R Utsugi J Maekawa 《Plastic and reconstructive surgery》1991,88(3):421-426
We have reported previously on a palatoplasty method, called the T-shaped musculomucosal buccal flap method, for the primary repair of a cleft palate. This method has been used on more than 90 patients, and satisfactory outcomes have resulted in terms of maxillar development, the prevention of fistulation, and verbal functions. However, 14.3 percent of these patients exhibited a velopharyngeal incompetence that showed no potential improvement through training. In the majority of these patients, the entire raw surface of the oral cavity side could not be covered with a buccal musculomucosal flap, and as a result, postoperative contraction of the soft palate occurred. Thus a new surgical method has proven effective in which both buccal musculomucosal flaps are used as an oral lining, the nasal mucosa having been extended by Z-plasty. We have performed 25 operations using this new method and have observed no postoperative contractions of the soft palate, notwithstanding two cases (8.0 percent) of postoperative fistulation. 相似文献