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11.
Fumio Iwata 《Hydrobiologia》1988,156(1):115-124
Summary The polystiliferous hoplonemertean Sagaminemertes nagaiensis (Iwata, 1957) has been redescribed.A distinct pre-cerebral region is wanting. The rhynchocoel opens directly at the tip of the head, whilst the mouth opens seperately below the ventral commissure of the brain which is situated at the anterior end of the head. The dorsal ganglia are well developed and extend posteriorly far behind the ventral ganglia. The cerebral sense organs are situated behind the brain and possess posterior ciliated canals. Cephalic glands are poorly represented, but ocelli are well developed. The sickle-shaped basis of the proboscis bears about 20 central stylets. The caecal appendages of the rhynchocoel are arranged pseudometamerically throughout the body. The foregut is straight, consisting of mouth, oesophagus, stomach and pylorus. Intestinal caeca and lateral diverticula are present. The cephalic lacunae have no anterior anastomosis. A cerebral lacuna is present, there is a rhynchocoel vessel, but transverse vessels are absent. The protonephridia extend throughout the foregut region. Mature spermatogonia are well developed.A systematic discussion of Sagaminemertes nagaiensis suggests that it is taxonomically close to Siboganemertes weberi in the archireptantic family Siboganemertidae.  相似文献   
12.
The effect of phospholipase C on two isozymes (alpha (+) and alpha forms) of rat brain (Na+ + K+)-ATPase and the temperature-dependence of their activities were investigated. Phospholipase C from Clostridium welchii inhibited the activities of the enzymes treated with and without pyrithiamin or N-ethylmaleimide, a preferential inhibitor of the alpha (+) form, but the extent of the inhibition was higher in the control enzyme than in the treated enzymes. The treatment of the (Na+ + K+)-ATPase with phospholipase C altered a ratio between high- and low-affinity components for ouabain inhibition. It also caused the similar change in a ratio between the alpha (+) and alpha forms of Na+-stimulated phosphorylation from [gamma-32P]ATP. These findings indicate that the alpha (+) form of rat brain (Na+ + K+)-ATPase is more sensitive to phospholipase C than the alpha form. Analysis of Arrhenius plots of the activities of the control and pyrithiamin-treated enzymes showed that there was a difference between the two enzymes in a break point. We suggest that two isozymes of rat brain (Na+ + K+)-ATPase differ in the interaction with phospholipids or in the lipid-environment.  相似文献   
13.
Histopathological examinations on nephlocalcinosis of the Fischer 344 (F344) rats were carried out. As the results of comparison on its appearance among F344, Wistar and SD strains of rats, F344 female rats showed the most severe nephrocalcinosis. Nephrocalcinosis developed between 4 weeks and 8 weeks and was likely to keep its appearance through 108 weeks of the survival period of the rats. Histologically, mineral deposit was always observed at cortico-medullary junction. It seemed to locate at the outer portion of the basement membrane of the tubular epithelium, adjacent to the capillary wall in the connective tissue. Four weeks after ovariectomy at 4 weeks of age, the rats showed a decrease in degree of nephrocalcinosis. In contrary, the rats treated with estorone following ovariectomy revealed an increase in degree of nephrocalcinosis. It was suggested that the oestrogen-type sex hormone appeared to give a role in nephlocalcinosis.  相似文献   
14.
Protoplast fusion of Lactobacillus fermentum.   总被引:1,自引:1,他引:0       下载免费PDF全文
M Iwata  M Mada    H Ishiwa 《Applied microbiology》1986,52(2):392-393
Tetracycline-resistant (Tetr) erythromycin-resistant (Eryr) fusants of Lactobacillus fermentum 604 carrying a 10-megadalton Tetr plasmid and L. fermentum 605 carrying a 38-megadalton Eryr plasmid were obtained by means of polyethylene glycol-induced protoplast fusion.  相似文献   
15.
A sensitized immunoblotting method was established for measuringsmall amounts of plant tubulin. The method involves electrophoretictransfer of protein including tubulin from SDS-polyacrylamidegels onto nitrocellulose paper, successive incubation of thenitrocellulose paper with a mouse monoclonal antibody to - orß-tubulin of chicken brain, an antibody to mouse IgGas the second antibody and the radioactive iodinated proteinA, and determination of the radioactivities of the bands onthe nitrocellulose paper thus probed. The radioactivities werelinearly proportional to the amounts of - or ß-tubulinfrom dark-grown Vigna mungo seedlings within a range of 4 to56 ng or of 4 to 32 ng, respectively. This method was used to estimate the tubulin contents of severalplant species using Vigna tubulin as a standard. -Tubulin contentsthus estimated were 25, 9, 19 and 11 µg-equivalents ofVigna tubulin per mg protein for Vigna seedlings, Daucus suspensioncells, Catharanthus suspension cells and Mougeolia cells, respectively.ß-Tubulin contents of Vigna, Daucus, Catharanthusand Mougeotia cells were 29, 10, 13 and 5 µg-equivalentsof Vigna tubulin per mg protein, respectively. (Received August 6, 1985; Accepted December 5, 1985)  相似文献   
16.
Rabbit antisera were raised against diacylglycerol kinase purified from pig brain cytosol. Upon immunoblot analysis, the antibody was specifically reactive with the kinase (Mr = 79,000-80,000). Pig brain cytosol, microsomal, and synaptosomal fractions all contained the immunoreactive Mr = 80,000 polypeptide, thus showing that the same enzyme is present in the soluble as well as membrane fractions of the brain. The antibody could precipitate only 60% of the kinase activity present in the crude cytosol. Further, the antibody exhibited very little or no cross-reactivity toward liver cytosolic enzymes obtained from different animals including pigs. Immunostaining of brain tissues demonstrated that neurons, in particular, their nuclei, were positively stained, whereas glial cells were not stained. It is likely that there exists a tissue-and/or cell-dependent immunological multiplicity of diacylglycerol kinase. The enzyme activities phosphorylating sn-1 and sn-2 monoacylglycerols were co-precipitated by the antibody, indicating their identity with diacylglycerol kinase. The enzyme activity toward sn-1 monoolein was much lower than that obtained with sn-2 monoolein. Enzymic as well as chemical analyses of acyl isomers of the reaction products showed that even tested with pure (greater than 95%) sn-1 monoolein, about 70% of the formed lysophosphatidate was of the sn-2 acyl type. The results show that diacylglycerol kinase phosphorylates almost exclusively the sn-2 acyl type of monoacyl-glycerol.  相似文献   
17.
Membrane-bound lipoxygenase of rat cerebral microvessels   总被引:5,自引:0,他引:5  
The microvessels isolated from rat cerebral cortex has arachidonate lipoxygenase activity, which was not due to possible contamination of the platelets. The major product was identified to be 12-hydroxyeicosatetraenoic acid. After homogenization and sonication of the microvessel preparations, the lipoxygenase activity was recovered both in the membrane- and the cytosol-fractions, whereas that in the platelets was recovered in the cytosol fraction. Membrane-bound lipoxygenase of the microvessels has apparent Km value of 3.8 microM for arachidonic acid, which was corresponded to 1/5 of that in the platelet enzyme. Microvessel lipoxygenase was inhibited by nordihydroguaiaretic acid but not by indomethacin.  相似文献   
18.
The effect of monoclonal antibodies to fibronectin-binding acid polysaccharide (anti-FAPS) on differentiation of primary mesenchyme cells and spicule formation was examined in cultured embryonic cells isolated from the sea urchin, Hemicentrotus pulcherrimus. Spicule formation of micromere-derived cells was enhanced by anti-FAPS. The increase of spicule formation correlated with the increase of calcium uptake into micromere-derived cells and spicules. Furthermore, both spicule formation and calcium uptake were inhibited by calcium-channel blockers (verapamil, diltiazem and nicardipine) and divalent ions (manganese and cobalt). These results suggest that FAPS, a component of the blastocoelic extracellular matrix surrounding the primary mesenchyme cells, may regulate the level of calcium uptake and spicule formation.  相似文献   
19.
We designed aldehyde derivatives of small peptides representing the C-terminal portion of angiotensin I sequence as an inhibitor of human renin. Among compounds that we synthesized, benzyloxycarbonyl (Z)-Phe-His-Leucinal (compound V), Z-Pro-Phe-His-Leucinal (Compound IV) and Z-[3-(1'-naphthyl)Ala]-His-Leucinal (compound VII) markedly inhibited human renin (IC50, 7.5 X 10(-7), 3.2 X 10(-7) and 8.0 X 10(-8) mol/l, respectively). Compound VII was shown to be noncompetitive (Ki = 2.4 X 10(-7) mol/l). It did not inhibit either cathepsin D or pepsin. Compound V had slight or no inhibitory effect at the concentration of 10(-5) mol/l on six animal renins except for monkey and rabbit renins. Results obtained show that these aldehyde compounds are highly selective and species specific inhibitors for human and monkey renins.  相似文献   
20.
A long-term follow-up study of rostral mesencephalic reticulotomy (RMR) for pain relief is presented. 34 patients (24 males and 10 females) were operated. Ages ranged from 18 to 65 years. The follow-up period was 1-70 months. The overall effectiveness of RMR showed good relief of pain in 23 patients (67%). The study of effectiveness of RMR according to type of pain showed good relief of pain in 5 out of 6 patients (83%) with nondenervation pain, whereas satisfactory pain relief was obtained in 18 out of 28 patients (64%) with denervation pain.  相似文献   
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