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981.
The taxonomy of the Vietnamese species of the social wasp subfamily Vespinae is revised. Vespa auraria Smith, 1852, is synonymized under V. velutina Lepeletier, 1836. Vespula koreensis (Radoszkowski, 1887) is recorded as new for Viet Nam, and its color characters are described. A key to vespine species of Viet Nam based on morphological characters is provided. 相似文献
982.
Stress-Induced Enhancement of Suppression of [3 H]GABA Release from Striatal Slices by Presynaptic Autoreceptor 总被引:1,自引:0,他引:1
Kinya Kuriyama Kouji Kanmori Jun-ichi Taguchi Yukio Yoneda 《Journal of neurochemistry》1984,42(4):943-950
The effect of cold and immobilization stress on presynaptic GABAergic autoreceptors was examined using the release of [3H]GABA (gamma-aminobutyric acid) from slices of rat striatum. It was found that in vitro addition of delta-aminolevulinic acid, as well as GABA agonists such as muscimol and imidazoleacetic acid, exhibited a significant suppression of the striatal release of [3H]GABA evoked by the addition of high potassium, whereas delta-aminovaleric acid had no significant effects on the evoked release. These suppressive actions were antagonized invariably by the GABA antagonists, bicuculline and picrotoxin, but not by the glycine antagonist, strychnine. Cholinergic agonists, such as pilocarpine and tetramethylammonium, also attenuated significantly the evoked release of [3H]GABA from striatal slices, while none of its antagonists, including atropine, hexamethonium and d-tubocurarine, affected the release. On the other hand, in vitro addition of dopamine receptor agents such as dopamine, apomorphine, and haloperidol, or the inhibitory amino acids, glycine, beta-alanine, and taurine failed to influence the evoked release of [3H]GABA from striatal slices. Application of a cold and immobilization stress for 3 h was found to induce a significant enhancement of the suppressive effects by muscimol and delta-aminolevulinic acid on the evoked release of [3H]GABA, without affecting that by pilocarpine and tetramethylammonium. These results suggest that the release of GABA from striatal GABA neurons may be regulated by presynaptic autoreceptors for this neuroactive amino acid, and may play a significant functional role in the exhibition of various symptoms induced by stress. 相似文献
983.
Yutaka Koga Jun-ichi Hamada Noritoshi Takeichi Akio Nakane Tomonori Minagawa Hiroshi Kobayashi 《Cancer immunology, immunotherapy : CII》1985,20(2):103-108
Summary We report here our study of the role of natural host defense mechanisms mediated by macrophages and natural killer (NK) cells in an experimental model of spontaneous pulmonary metastases of a mammary adenocarcinoma SST-2 in spontaneously hypertensive rats (SHR) with congenital T-cell depression. To activate macrophages and NK cells, Listeria monocytogenes (LM) was injected IV into SHR which had received a transplantation of SST-2. To assess the antimetastatic responses induced by LM, the number of lung nodules and the lung weight in SHR were evaluated 30 days after tumor inoculation. The growth of lung metastases, though not of primary tumors, was significantly reduced if 107 LM were injected IV into SHR 2, 10 and 20 days after the SC transplantation of 5×104 or 5×105 SST-2. An inhibitory effect of LM on pulmonary metastases was also observed in tumor-excised rats, in which the number of lung metastases and the lung weight were enhanced as compared with those in tumor-bearing rats which had not undergone surgery. Peritoneal resident cells which were harvested from rats injected with LM showed a significant augmentation of tumoricidal activity against SST-2 cells as measured by in vitro cytotoxicity. Similarly, the NK activity of spleen cells of SHR injected with LM increased significantly when compared with untreated SHR. These data suggest that the inhibition of metastatic growth, though not of pirmary tumor growth, was accomplished by the, possibly T-cell independent, activation of macrophages and NK cells. 相似文献
984.
Jun-ichi Abe Frederico W. Bergmann Kazuaki Obata Susumu Hizukuri 《Applied microbiology and biotechnology》1988,27(5-6):447-450
Summary
Aspergillus sp. K-27, isolated from soil, produced extracellular glucoamylase and -amylase using wheat starch as a carbon source, and its productivity was doubled by the addition of -methyl-d-glucoside to the medium. The crude enzyme preparation, which was found to be a mixture of 70% glucoamylase and 30% -amylase, well degraded not only cereal starches but also tuber and root starches, and the initial velocity for potato starch was 72% of that for corn starch. 相似文献
985.
986.
Intact chloroplasts were isolated from mesophyll and bundlesheath protoplasts of a C4 plant, Panicum miliaceum L., to measurethe uptake of [1-14C]pyruvate into their sorbitol-impermeablespaces at 4?C by the silicone oil filtering centrifugation method.When incubated in the dark, both chloroplasts showed similarslow kinetics of pyruvate uptake, and the equilibrium internalconcentrations were almost equal to the external levels. Whenincubated in the light, only mesophyll chloroplasts showed remarkableenhancement of the uptake, the internal concentration reaching1030 times of the external level after 5 min incubation.The initial uptake rate of the mesophyll chloroplasts was enhancedabout ten fold by light and was saturated with increasing pyruvateconcentration; Km and Vmax were 0.20.4 mM and 2040µmol(mg Chl)1 h1, respectively. The lightenhancement was abolished by DCMU and uncoupling reagents suchas carbonylcyanide-m-chlorophenylhydrazone and nigericin. Theseresults indicate the existence of a light-dependent pyruvatetransport system in the envelope of mesophyll chloroplasts ofP. miliaceum. The uptake activity of mesophyll chloroplastsboth in the light and the dark was inhibited by sulfhydryl reagentssuch as mersalyl and p-chloromercuriphenylsulfonate, but thebundle sheath activity was insensitive to the reagents. Thesefindings are further evidence for the differentiation of mesophylland bundle sheath chloroplasts of a C4 plant with respect tometabolite transport. (Received July 3, 1986; Accepted October 8, 1986) 相似文献
987.
Tadao Horichi Hideo Koga Hachiro Inokuchi Jun-ichi Tomizawa 《Molecular & general genetics : MGG》1969,104(1):51-58
Summary Weak-virulent mutants of temperate coli-phage were isolated which can grow on the CIts lysogen producing a temperature-sensitive repressor but which cannot grow on the wild type lysogen producing a normal repressor.Genetic analysis on the mutants shows that their weak-virulence is attributable to two mutations, one (virL) in the region between sus N213 and c
47 and the other (virR) in the region between c
1 and sus O8. Both mutations are located within the region of non-homology between and imm
434 phages.True virulent mutants which can grow on the wild type lysogen can be obtained easily from the weak-virulent mutant by an additional mutation, virC in a region very close to virR. The virulent mutants obtained are similar to the classical vir mutant (Jacob and Wollman, 1954). The virL and virR mutations are probably operator mutations which render the genome insensitive to the repressor.This work was reported at the XII th International Congress of Genetics, held in Tokyo, on August 23, 1968. 相似文献
988.
Summary A mentally retarded boy with trisomy 9p is described. This trisomy arose through aberrant segregation of translocation chromosome during meiosis in his mother, who has a complex translocation involving chromosomes 9, 13, and 14. Based on both G-, Q-banding, and DNA replication patterns, the patient's karyotype was identified as 47,XY,-13, +(9;13) (9pter9q12::13q3113qter), +t(13;14) (13pter13q31::14pl?14pter). We suppose his mother's karyotype to be 46,XX,-9,-13,-14,+t(9;13) (9pterq12::13q3113qter), +t(13;14) (13pter13q31::14pl?14pter), +t(9;14) (9qter9q12::14pl?14qter). His phenotypically normal brother and sister are also carriers, having the same translocation chromosome as their mother. Clinical findings of the patient included peculiar face with hypertelorism, prominent nasal bridge and deformed helix, marked delay of osseous development, hypoplastic phalangia in fingers and toes, dysplastic nails and absence of digital triradii. 相似文献
989.
Seven lymphoblastoid cell lines were established through transformation by Epstein-Barr virus of peripheral blood lymphocytes from two patients with Bloom's syndrome (BS), the parents of a patient, and normal controls. High baseline levels of sister chromatid exchanges (SCEs) in peripheral blood lymphocytes of BS were reduced to about 10% of their initial value in BS lymphoblastoid cell lines, and the elevation of SCE frequencies induced by ethylmethanesulfonate was the same as in controls. 相似文献
990.