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排序方式: 共有847条查询结果,搜索用时 250 毫秒
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A Miura Y Ukai T Matsuzaki N Taniguchi S Hayashi S Kano Y Kimura K Kimura H Enomoto 《Arzneimittel-Forschung》1986,36(9):1323-1328
The effects of methyl 2,6-dimethyl-4-(2-nitrophenyl)-5-(2-oxo-1,3,2-dioxaphosphorinan-2- yl)-1,4- dihydropyridine 3-carboxylate (DHP-218), a new dihydropyridine calcium antagonist, on vascular smooth muscles, cardiac muscles and [3H]-nitrendipine binding to the cardiac muscle and brain membranes were investigated in vitro. Vascular smooth muscles: Calcium-induced contraction of the rat aorta in high K+ solution was inhibited by DHP-218 with the pA2 value of 9.11. The IC50 value for the inhibitory effects of this compound in high K+-induced and phenylephrine-induced contraction was 6.3 nmol/l and 66 nmol/l, respectively. Vasodilatory effects of this drug on various blood vessels of rabbits contracted by high K+ appeared to a similar extent. The onset of the vasodilatory effect was very slow and the recovery rate of vasodilatory response after washout with the bathing solution containing high K+ or phenylephrine was also very slow. Cardiac muscles: Negative chronotropic and inotropic actions were observed at concentrations more than 30 and 100 nmol/l, respectively. Duration of the plateau phase of normal action potential was shortened and the amplitude and duration of slow action potential were reduced at concentrations more than 1 mumol/l. Very high vasculoselectivity was observed. Displacement of [3H]-nitrendipine binding: The pattern of displacement of [3H]-nitrendipine binding by DHP-218 was very similar to that of other 1,4-dihydropyridines but this compound was about 70 times less potent than nifedipine in [3H]-nitrendipine displacement capacity. These results indicate that DHP-218 has specific vasodilatory action due to calcium antagonism, but association and dissociation rates with tissue and receptors were different from those of nifedipine. 相似文献
3.
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
4.
Sleep spindles are an EEG sign of light sleep under physiological conditions. We reported the simultaneous occurrence of sleep spindles and alpha activity in the waking EEG in 12 patients with a mean age of 59.0 years. Most of the patients were diagnosed as cerebrovascular disorders such as cerebral arteriosclerosis, transient ischemic attack and vascular dementia. The mean alpha frequency in the presence of WSA significantly decreased by 1.5 Hz. The frequency and spatial distribution of waking spindle activity were similar to those of sleep spindles. In our cases, at least the two factors of cerebrovascular involvement and older adults were considered to be primarily responsible for the intrusion of sleep spindles into wakefulness (presumably a state close to very light drowsiness) due possibly to the instability of sleep-waking cycle regulation. 相似文献
5.
Shigeru Onodera Koji Saito Takafumi Saito Hitoshi Togashi Sumio Kawata Katsuaki Ukai Haruhide Shinzawa 《Nihon Shokakibyo Gakkai zasshi》2007,104(2):213-218
It is well known that long-term infection with Clonorchis sinensis often causes bile duct cancer, usually. It occurs in the intrahepatic bile duct. We encountered a rare case of clonorchiasis complicated with duodenal papillary cancer. The patient was a woman from China. Although clonorchiasis is rarely found in Japan, the promotion of international exchange may increase the number of visitors from endemic areas. Thus we must pay sufficient attention to this disease. Also, we reported that the microplate ELISA technique was useful in the diagnosis of clonorchiasis with high accuracy in this case. 相似文献
6.
7.
The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H2O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H2O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (Ra; +100%), glucose rate of disappeaance (Rd; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite 相似文献
8.
The effect of amlexanox given orally for 3 weeks was studied on the IgE-mediated experimental allergic rhinitis in the actively sensitized guinea pigs. The intranasal instillation of antigen (egg albumin) induced the increase of nasal vascular permeability (dye leakage), histamine content in nasal perfusate and nasal resistance in sensitized guinea pig. Amlexanox, 20 and 60 mg/kg/day given orally for 3 weeks significantly inhibited the increase of dye leakage into the nasal cavity, histamine content and nasal resistance in a dose-dependent manner. These results suggest that amlexanox given orally may be useful therapeutic agent for human allergic rhinitis. 相似文献
9.
Yang M Moriya T Oguma M De La Cruz C Endoh M Ishida T Hirakawa H Orita Y Ohuchi N Sasano H 《Pathology international》2003,53(7):422-428
Microinvasive ductal carcinoma of the breast, namely ductal carcinoma in situ with microinvasion (T1mic) as defined by the American Joint Committee on Cancer (AJCC) Staging Manual, is a rare disease, although it is increasing because of widespread use of mammography. The aim of the present study was to describe the clinicopathological and immunohistochemical features of this entity. Twenty-eight patients who were diagnosed as T1mic from January 1997 to August 2002 were studied by using 3-5 mm-thick serial sections with hematoxylin-eosin staining. Immunohistochemical staining for the estrogen receptor (ER), progesterone receptor (PR), p53, Ki-67, and HER-2 were performed. All 28 patients were female, with a mean age of 48.8 years. Twenty-six patients (93%) revealed mammographic abnormalities on routine examination. All foci of the invasions were measured using an ocular micrometer. Invasive foci consisted of isolated cells or cell clusters, or appeared as a tongue-like projection of tumor through the basement membrane of the duct of ductal carcinoma in situ (DCIS). The mean number of invasive foci was 3, and the mean size was 0.6 mm. We found that high nuclear grade and predominant comedo subtype of DCIS components were 57.1% and 46.4%, respectively. Twenty-four cases (86%) demonstrated necrosis of DCIS components. Microinvasion was often associated with periductal stromal reaction (71.5%) and/or a lymphocytic infiltration (78.6%). All patients, excluding two, received axillary resection (the mean number of lymph nodes examined per case was 12), and none had lymph node metastasis. The positive expression of ER and PR strongly related to low grade nuclei and non-comedo subtype; however, the positive expression of HER-2 and P53 related to high grade nuclei and comedo subtype (P<0.01). Ki-67 expression was significantly higher in the high grade nuclei group than in the low grade group (P<0.01). Our study suggested that high nuclear grade and comedo DCIS were more aggressive and more common with microinvasion, and that microinvasion is more likely to be multifocal. 相似文献
10.
The effects of naltrexone on the behavior in mice were investigated by using a multi-dimensional behavioral analyser. Within 15 min following observation, naltrexone preferentially suppressed the linear locomotion at the 10 and 30 mg/kg doses. The results suggest that naltrexone selectively disrupts the linear locomotion without affecting other behaviors in mice. 相似文献