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991.
Seiji Ichida Tetsuyuki Wada Kiyo Hashimoto Yasunari Kasamatsu Takafumi Akimoto Miki Tahara 《Neurochemical research》1996,21(6):675-680
Specific binding and specific labeling of125I-ω-CgTX were investigated in crude membranes from both subfractionated fractions and various brain areas in chick whole brain.
The specific activities of the marker enzymes 2′,3′-cyclic nucleotide 3′-phosphorylase, Na/K ATPase and succinic dehydrogenase
in the subfractionated fractions were three- to five-fold higher than those in the P2 fraction. However, the amount of specific [125I]ω-CgTX binding in the fractions of synaptosomes and synaptic plasma membranes was only about 1.2-times higher than that
in the P2 fraction. The characteristics of specific125I-ω-CgTX labeling with disccinimidyl suberate to the 135-kDa band were generally comparable to those of specific [125I]ω-CgTX binding sites. These results suggest that the specific binding sites of [125I]ω-CgTX were not localized the synaptosomes and synaptic plasma membranes fractions, although each fraction was well isolated
from the others from which were decided by the strength of specific activity for marker enzymes. 相似文献
992.
Kenji Motokawa Tsutomu Hohdatsu Hiroshi Hashimoto Hiroyuki Koyama 《Microbiology and immunology》1996,40(6):425-433
Complete nucleotide sequences were determined by cDNA cloning of peplomer (S), integral membrane (M) and nucleocapsid (N) genes of feline infectious peritonitis virus (FIPV) type I strain KU-2, UCD1 and Black, and feline enteric coronavirus (FECV) type II strain 79–1683. Only M and N genes were analyzed in strain KU-2 and strain 79–1683, which still had unknown nucleotide sequences. Deduced amino acid sequences of S, M and N proteins were compared in a total of 7 strains of coronaviruses, which included FIPV type II strain 79–1146, canine coronavirus (CCV) strain Insavc-1 and transmissible gastroenteritis virus of swine (TGEV) strain Purdue. Comparison of deduced amino acid sequences of M and N proteins revealed that both M and N proteins had an identity of at least 90% between FIPV type I and type II. The phylogenetic tree of the M and N protein-deduced amino acid sequences showed that FIPV type I and type II form a group with FECV type II, and that these viruses were evolutionarily distant from CCV and TGEV. On the other hand, when the S protein-deduced amino acid sequences was compared, identity of only about 45% was found between FIPV type I and type II. The phylogenetic tree of the S protein-deduced amino acid sequences indicated that three strains of FIPV type I form a group, and that it is a very long distance from the FIPV type II, FECV type II, CCV and TGEV groups. 相似文献
993.
Eiichi Kodama Akira Igarashi Shuichi Mori Kou-Ichi Hashimoto Toshimitsu Suzuki Erik De Clercq Shiro Shigeta 《Microbiology and immunology》1996,40(5):359-363
We developed a rapid and simple method for the screening of antiviral agents against herpes simplex virus (HSV) in a model of gastrointestinal herpetic infection in vitro. This method was based on inhibition of HSV-induced cytopathogenicity in gastric adenocarcinoma MKN-28 cells, as monitored by an MTT colorimetric assay. From the various compounds that were evaluated for their activity against HSV-1 and HSV-2, brivudine (BVDU) emerged as the most effective. When the 50% effective concentration (EC50) values of the antiherpes agents in MKN-28 cells were compared with those in human embryo lung MRC-5 cells, all compounds, except for BVDU, showed higher EC50 values in MKN-28 cells. For BVDU the EC50 values in MKN-28 cells were 0.8 (HSV-1) and 0.036 (HSV-2) times the EC50 values in MRC-5 cells. Thus BVDU was 27.5 times more active against HSV-2 in MKN-28 cells than in MRC-5 cells. The MKN-28 gastric cancer cells may be useful for the rapid screening of anti-HSV agents and, in particular, those that may be useful in therapy of gastrointestinal HSV infections in gastrointestinal herpetic infection. 相似文献
994.
Ikuo Takashima Maki Hiyoshi Hiroaki Kariwa Ryusuke Mukaiya Nobuo Hashimoto 《Microbiology and immunology》1996,40(4):265-270
Japanese quail were used for the infection model of avian chlamydiosis. One-day-old Japanese quail were highly susceptible to lethal infection by a Chlamydia psittaci strain of budgerigar origin upon inoculation via the air sac route with 104.1 FFU of the organism, showing an acute and lethal course with chlamydial propagation. In contrast, 7-day-old quail developed resistance to the infection as shown by the lack of lethal effect with the same dose. The resistance of 7-day-old birds was abolished by immunosuppressive treatment with cyclophosphamide. Upon inoculation with a sublethal dose of 102.1 FFU, latent infection was established in 1-day-old birds with a minimum number of the organism. The latent infection in the birds was converted to the lethal form by treatment with cyclophosphamide along with chlamydial propagation and suppression of antibody production. 相似文献
995.
996.
Developmental expression of extracellular matrix components in intramuscular connective tissue of bovine semitendinosus muscle 总被引:4,自引:0,他引:4
T. Nishimura Kouichi Ojima Akihito Hattori Koui Takahashi 《Histochemistry and cell biology》1997,107(3):215-221
We have investigated the expression patterns of extracellular matrix components in intramuscular connective tissue during
the development of bovine semitendinosus muscle by means of indirect immunofluorescence techniques. Types I, III, V, and VI
collagen and fibronectin were located in the endomysium and the perimysium. Type IV collagen, laminin, and heparan sulfate
proteoglycans (PGs) were exclusively located in the endomysium, and dermatan sulfate PGs existed only in the perimysium. The
localization of these components in the intramuscular connective tissue of semitendinosus muscle remained unchanged throughout
prenatal and postnatal growth of cattle, suggesting that they are essential for forming and maintaining structures of the
endomysium and perimysium in bovine semitendinosus muscle. On the other hand, decorin was undetectable in the endomysium of
neonates, although other matrix components were already expressed. It was expressed slightly in the endomysium of 2-month-old
calves, and clearly detectable in the endomysium of cattle more than 6 months old. Chondroitin sulfate PGs were barely detectable
in the perimysium of fetuses and neonatal calves, and progressively appeared during postnatal development of the muscle. It
seems likely that these PGs are closely related to the postnatal development of the endomysium and perimysium.
Accepted: 30 October 1996 相似文献
997.
998.
Cell-cycle-regulated transcription of A- and B-type plant cyclin genes in synchronous cultures 总被引:5,自引:3,他引:2
999.
1000.
Toru R Saito Takayuki Tatsuno Akira Takeda Haruo Hashimoto Mitsuro Suzuki Misao Terada Shinobu Aoki-Komori Minoru Tanaka Lajos Koranyi Gyorgy M Nagy 《Experimental Animals》2004,53(5):445-451
It is well known that circulating leptin concentrations correlate with adiposity in both humans and rodents and decrease after fasting, energy restriction, or weight loss. The goal of the present study was to confirm whether the decreases of copulatory behavior and the increases of ingestive behavior in STZ-induced diabetic male rats could be reversed by i.c.v. administration of leptin. Adult male Wistar-Imamichi rats aged 9 weeks were used for the studies. Males received a single injection of STZ (60 mg/kg, i.p.) and vehicle. During the experiment, individual body weight, and food and water intake were measured. The copulatory and ingestive behaviors in STZ-induced diabetic males were observed at 2 and 4 weeks after STZ. At 6 weeks after STZ, leptin (10 microg/10 microl) or aCSF (artificial cerebrospinal fluid) was injected through a lateral ventricle cannula and the above two behaviors were observed again. The i.c.v. leptin injection to STZ-induced diabetic males resulted in a significant increase of ejaculation frequencies (3.6 +/- 0.26 vs. 2.9 +/- 0.30 times) and a significant decrease in amount of food ingested (36.2 +/- 1.93 vs. 23.2 +/- 3.76 g), compared with the aCSF-injected control (p<0.01). These findings suggest that the copulatory and ingestive behaviors in i.c.v. leptin-injected STZ diabetic males were restored to levels equivalent to those in control males. 相似文献