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91.
Photoautotrophic and photomixotrophic growth of strawberry plantlets in vitro and changes in nutrient composition of the medium 总被引:3,自引:0,他引:3
T. Kozai K. Iwabuchi K. Watanabe I. Watanabe 《Plant Cell, Tissue and Organ Culture》1991,25(2):107-115
Explants excised from strawberry (Fragaria x ananassa Duch.) plantlets were cultured in vitro for 21 days on half-strength MS (Murashige & Skoog 1962) basal liquid medium with 20 g l-1 sucrose and without sugar in the vessels capped with gas permeable microporous polypropylene film. The experiments were conducted under CO2 nonenriched (350–450 mol mol-1 in the culture room) and CO2 enriched (2,000 mol mol-1 during the photoperiod in the culture room) conditions with a PPF (photosynthetic photon flux) of 200 mol m-2 s-1. The CO2 concentration in the vessels decreased to approximately 200 mol mol-1 during the photoperiod on day 21 under CO2 nonenriched conditions. The fresh and dry weight, net photosynthetic rate (NPR) per plantlet, NPR per g leaf fresh weight, NPR per g leaf dry weight, the number of unfolded leaves, and ion uptake of PO4
3-, NO3
-, Ca2+, Mg2+ and K+ on day 21 were the greatest under photoautotrophic (no sugar in the medium) and CO2 enriched conditions. The residual percent of PO4
3- was 3% on day 21 under photoautotrophic and CO2 enriched conditions.Abbreviations MS
Murashige & Skoog (1962) basal medium composition
- NPR
net photosynthetic rate
- PPF
photosynthetic photon flux 相似文献
92.
Summary Cellular and subcellular localizations of gastrin-releasing peptide-like immunoreactivity (GRP-LI) were examined in the perikarya of trigeminal ganglion cells. By immunolight microscopy using semi-thin sections, GRP-LI was observed in almost all the neuronal somata with various intensity as granular profiles distributing widely in the cytoplasm. By immunoelectron microscopy using ultrathin frozen sections and protein A-gold, GRP-LI was found predominantly in rounded or oval membrane-bound structures which were 300–800 nm in diameter and displayed various electron-density and heterogenous contents. Double-labeling immunoelectron microscopy using antibodies for GRP and cathepsin L, a well-characterized lyosomal proteinase, clearly demonstrated that these GRP-immunoreactive intracytoplasmic structures were lysosomes. In contrast, GRP-LI was detected only occasionally in the large granular vesicles (100–200 nm in diameter). These findings strongly suggest that considerable amount of GRP or GRP-like peptide is subject to intracellular degradation in the lysosome rather than to the regulatory secretion pathway, and this is the reason why no fibers immunoreactive for GRP have been detected in the peripheral sensory field. 相似文献
93.
R Y Osamura Y Suemizu S Yoshimura S Hori K Inada K Watanabe Y Nakai H Imura 《Peptides》1991,12(3):503-507
In order to elucidate the relationship between secretory pathway and processing for precursor molecule of peptide hormones, we performed immunoelectron microscopic studies to localize POMC-derived peptides in mouse cultured L cells (fibroblasts without secretory granules) and in mouse AtT20 cells (ACTH secreting pituitary tumor cells with secretory granules) which had been transformed with human POMC gene. From the electron microscopic localization patterns, L42 cells were considered to serve as a model of constitutive pathway without processing of POMC, and A53 cells were considered to serve as a model of transgranular (regulated) pathway with processing of POMC. Immunoblotting supported these interpretations. 相似文献
94.
M Sekiguchi K Watanabe M Eto Y Iwashima A Morikawa M Takahashi K Ishii I Makino 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,98(4):637-640
1. Sorbitol and fructose levels were significantly elevated in the lens, the sciatic nerve, the retina and the kidney of diabetic Chinese hamsters and inositol level was significantly decreased in the lens and sciatic nerve of diabetics. 2. The activity of an aldose reductase in the kidney was not different between normal and diabetic Chinese hamsters. 3. An aldose reductase inhibitor (ONO-2235) had no effect in sorbitol, fructose and inositol contents of all these tissues from diabetic Chinese hamsters. 4. These results suggest that diabetic Chinese hamsters produce polyol accumulation in tissues but that there is a clear species-specific difference to inhibition of aldose reductase. 相似文献
95.
A novel cloverleaf structure found in mammalian mitochondrial tRNA(Ser) (UCN). 总被引:6,自引:3,他引:3 下载免费PDF全文
T Yokogawa Y Watanabe Y Kumazawa T Ueda I Hirao K Miura K Watanabe 《Nucleic acids research》1991,19(22):6101-6105
Bovine mitochondrial tRNA(Ser) (UCN) has been thought to have two U-U mismatches at the top of the acceptor stem, as inferred from its gene sequence. However, this unusual structure has not been confirmed at the RNA level. In the course of investigating the structure and function of mitochondrial tRNAs, we have isolated the bovine liver mitochondrial tRNA(Ser) (UCN) and determined its complete sequence including the modified nucleotides. Analysis of the 5'-terminal nucleotide and enzymatic determination of the whole sequence of tRNA(Ser) (UCN) revealed that the tRNA started from the third nucleotide of the putative tRNA(Ser) (UCN) gene, which had formerly been supposed. Enzymatic probing of tRNA(Ser) (UCN) suggests that the tRNA possesses an unusual cloverleaf structure with the following characteristics. (1) There exists only one nucleotide between the acceptor stem with 7 base pairs and the D stem with 4 base pairs. (2) The anticodon stem seems to consist of 6 base pairs. Since the same type of cloverleaf structure as above could be constructed only for mitochondrial tRNA(Ser) (UCN) genes of mammals such as human, rat and mouse, but not for those of non-mammals such as chicken and frog, this unusual secondary structure seems to be conserved only in mammalian mitochondria. 相似文献
96.
Shin'ichi Saito Tamotsu Inoue Ichiro Kawase Hideki Hara Yoshiro Tanio Isao Tachibana Seiji Hayashi Masatoshi Watanabe Machiko Matsunashi Tadashi Osaki Tomiya Masuno Susumu Kishimoto 《Cancer immunology, immunotherapy : CII》1991,33(3):165-170
Summary Murine IgG1 monoclonal antibodies (mAbs), ITK-2 and ITK-3, were generated against a small-cell lung cancer (SCLC) cell line. Enzyme-linked immunosorbent assay using a variety of established cell lines as substrates, immunoperoxidase staining of freshly frozen tissue sections, and fluorescence-activated cell sorter analysis of peripheral blood leukocytes showed that these mAbs recognize a part of the SCLC-associated cluster 1 antigen. In immunoprecipitation studies, both ITK-2 and ITK-3 bound to a 145-kDa glycoprotein of SCLC cell membrane extracts, as did MOC-1 and NKH-1, which both recognize the cluster 1 antigen. However, because the binding of125I-labeled ITK-2 to SCLC cells was not inhibited by MOC-1 or NKH-1, the binding site of ITK-2 on SCLC cells appeared to be different from that of either MOC-1 or NKH-1. Unexpectedly, binding of125I-labeled ITK-2 to SCLC cells increased in the presence of ITK-3. This ITK-3-induced increase in ITK-2 binding was due partly to an increase in the number of binding sites for ITK-2 on SCLC cells. Addition of ITK-3 may, therefore, improve the effectiveness of ITK-2-based tumor detection or therapy. 相似文献
97.
Guanidinoethanesulfonic acid (GES) is known to induce convulsive seizures when administered intracisternally to rabbits and cats. The effects of GES on behavior, electroencephalographic recording and brain monoamine levels were examined in mice. When GES (900 nmol) was intraventricularly injected into mice, focal clonic movements of the face, vibrissae and ears together with twitching of the limbs were observed 0.5–1 min after the injection. Hypersensitivity was observed up to 7 min after the injection, after which the mice behaved normally. GES also induced sporadic spike discharges on electrocorticogram. The levels of 5-hydroxytryptamine (5-HT) of the GES-injected mice were lower than those of the saline-injected mice in the hippocampus, diencephalon, pons-medulla oblongata and cerebellum 5 min after the injection. No changes in the norepinephrine or dopamine levels were found after the GES injection. The level of 5-hydroxyindoleacetic acid increased in the striatum and cerebellum 5 min after the GES injection. These results suggest that GES-induced convulsive activities enhance the serotonergic neuroactivity in order to suppress the convulsions. 相似文献
98.
T. R. Deason P. C. Silva S. Watanabe G. L. Floyd 《Plant Systematics and Evolution》1991,177(3-4):213-219
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris
Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia.
Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class. 相似文献
99.
A new plasmid-mediated beta-lactamase (FPM-1) with an isoelectric point of 7.2 and a molecular weight of 26,000 was found in a cefuroxime-resistant clinical isolate of Proteus mirabilis strain 6003. FPM-1 can be classified as a type I oxyimino-cephalosporinase on the basis of its substrate specificity and inhibition pattern by clavulanic acid etc., and its conferred resistance on both the strain and transconjugants against most oxyme-type cephalosporins as well as the older ones but not against cefamycins and a few exceptional oxyme-type cephalosporins such as ceftizoxime, ceftazidime and cefixime. In a murine systemic infection model, only these FPM-1-stable drugs exhibited protective activity against the FPM-1-producing P. mirabilis 6003 similar to that against a nonproducing derivative strain. The FPM-1-mediated cefuroxime resistance in P. mirabilis 6003 was transferred to co-infected Escherichia coli 7004 at frequencies between 3.8 x 10(-3) and 4.0 x 10(-2) in a murine ascending urinary tract infection model. In the same infection model due to the FPM-1-producing E. coli transconjugant, FPM-1-stable cefixime was significantly more effective than FPM-1-labile cefteram pivoxil, although both drugs had similar therapeutic effect against its FPM-1-nonproducing counterpart strain. 相似文献
100.
A procedure is described for preparation of highly active (Na+,K+)-ATPase from rat heart which has a specific activity of 200-600 mumol Pi/mg/h. The procedure is simple and can be applied to small amounts of heart muscle (approximately 1 g). The ATPase activity was more than 90% sensitive to ouabain (at concentrations up to 1 mM). The ouabain sensitivity is biphasic with about 20% of the ATPase activity being inhibited at approximately 3 X 10(-7) M ouabain. 相似文献