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排序方式: 共有4419条查询结果,搜索用时 31 毫秒
1.
Changes in central dopaminergic systems with the expression of Shh or GDNF in mice perinatally exposed to bisphenol-A. 总被引:1,自引:0,他引:1
Kazuya Miyagawa Minoru Narita Michiko Narita Keiichi Niikura Hisahiko Akama Yuri Tsurukawa Tsutomu Suzuki 《Nihon shinkei seishin yakurigaku zasshi》2007,27(2):69-75
In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development. 相似文献
2.
Keijiro Sunada Hironori Yamamoto Hiroto Kita Tomonori Yano Tomohiko Miyata Yutaka Sekine Akiko Kuno Nobuki Onishi Michiko Iwamoto Atsuhiro Sasaki Kenichi Ido Kentaro Sugano 《Digestive endoscopy》2004,16(3):237-240
The requirement for endoscopic access to a stricture is a major limitation of the endoscopic dilatation for the treatment of strictures in the gastrointestinal tract. We have developed the double‐balloon enteroscopy method that enables visualization of the entire small bowel. In addition, double‐balloon enteroscopy has a potential for the interventional therapy including dilatation of strictures. We present here a case of jejunal strictures in a 47‐year‐old woman with Crohn's disease successfully treated with a balloon catheter in combination with double‐balloon enteroscopy. Balloon dilation with double‐balloon enteroscopy is a promising method for the treatment of small bowel strictures in Crohn's disease. 相似文献
3.
4.
S Kato T Morie K Hino T Kon S Naruto N Yoshida T Karasawa J Matsumoto 《Journal of medicinal chemistry》1990,33(5):1406-1413
With the purpose of obtaining more potent and selective gastric prokinetic than metoclopramide (1), a new series of N-[(2-morpholinyl)alkyl]benzamides (17-52) were synthesized and their gastric prokinetic activity was evaluated by determining effects on the gastric emptying of phenol red semisolid meal and of resin pellets solid meal in rats and mice. The morpholinyl moiety was newly designed after consideration of the side-chain structure of cisapride (2) and produced the desired activity when coupled with the 4-amino-5-chloro-2-methoxybenzoyl group of both metoclopramide and cisapride. Modification of the substituents of the benzoyl group markedly influenced the activity. In particular, 4-amino-N-[(4-benzyl-2-morpholinyl)methyl]-5-chloro-2-methoxybenzamide (17) and the 4-(dimethylamino) and 2-ethoxy analogues (25 and 29) of 17 showed potent and selective gastric prokinetic activity along with a weak dopamine D2 receptor antagonistic activity. 相似文献
5.
A Fujie T Iwamoto N Shigematsu M Ezaki M Hino S Hashimoto M Okuhara M Kohsaka H Imanaka 《The Journal of antibiotics》1990,43(5):449-455
FR112123 is a new oligopeptide antibiotic produced by Streptomyces viridochromogenes No. 7587. The structure of FR112123 is elucidated as N-(N6-(N2-glycyl-L-glutaminyl)-D-lysyl)-D-alanine (1) by spectroscopic and chemical evidence. It resembles a partial structure of peptidoglycan in bacteria. The compound has a superior activity against an Escherichia coli mutant sensitive to inhibitors of cell wall synthesis, although it has a weak activity against the parent strain. These suggest that FR112123 might act on the biosynthesis of bacterial cell wall. 相似文献
6.
Michiko Oka Y. Itoh Shigeru Tatsumi F.-H. Ma Yojiro Ukai Yoshiaki Yoshikuni Kiyoshi Kimura 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):189-196
The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity
was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10–7 and 10–6 M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins.
Conversely, in pertussis toxin-pretreated neurons, NS-105 (10–7 –10–5 M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera
toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1, 3-dicarboxylic acid (1S, 3R-ACPD) produced
similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and
1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10–6 M) and 1S, 3R-ACPD (10–4 M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled
receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate
(L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10–4 M) but not by NS-105 (10–6 M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest
that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate
cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis.
Received: 3 February 1997 / Accepted: 25 April 1997 相似文献
7.
Yukio Fukuyama Tohru Seki Chikaya Ohtsuka Hisao Miura Michiko Hara 《Brain & development》1996,18(6):144-484
Recent studies have shown that adequate medication can prevent the recurrence of febrile seizures (FS). It has also been clarified that the vast majority of, though not all, FS patients follow a benign course. Then, questions arise as to whether or not FS should be prevented, particularly in light of the risks of side effects from drugs. Which kinds of FS can be prevented, if necessary? The guidelines presented here are aimed primarily at helping general practitioners in considering how to manage FS most appropriately. The guidelines stress that judgements should be individualized, while referring to a few specific ‘warning factors’. The guidelines follow a ‘laissez-faire’ principle for the majority of FS cases, whereas intermittent therapy with diazepam and continuous medication with either phenobarbital or valproate are indicated in other limited cases meeting respective definite criteria. 相似文献
8.
Kanta Kishi Michiko Muramatsu Denan Jin Keiichi Furubayashi Shinji Takai Hiroshi Tamai Mizuo Miyazaki 《Hypertension research》2007,30(1):77-83
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries. 相似文献
9.
Yusen Chen Jun Nakura Jing-Ji Jin Zhihong Wu Miyuki Yamamoto Michiko Abe Yasuharu Tabara Yoshikuni Yamamoto Michiya Igase Xiao Bo Katsuhiko Kohara Tetsuro Miki 《Hypertension research》2003,26(6):439-444
The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension. 相似文献
10.
Kunihiro Ichinose Mitsuru Nakamura Kenji Takezawa Ichiro Masutomi Yoichi Shima Yoko Hirayama Kahoko Sorimachi Teruhiko Shimizu Hiroyo Ishikawa Namiko Kaji Sayaka Nakajima Michiko Wataru Shiho Nishigaki Hiroshi Suwa Yosuke Toyama Masaki Okumura Yoshikazu Ishitsuka Ken Shimizu Kazuya Kokubo Kenji Sasaki Shodai Saito 《Seishin shinkeigaku zasshi》2006,108(9):945-954