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Sato T, Sasaki T, Tsuchida K, Shiraishi K, Kawakami S. Scattering mechanism and reduction of insertion losses in a laminated polarization splitter. APPLIED OPTICS 1994; 33:6925-6934. [PMID: 20941239 DOI: 10.1364/ao.33.006925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We experimentally found the unexpected phenomena of scattering in laminated polarization splitters (LPS's) composed of a-Si:H-SiO(2) multilayer and studied its mechanism. The scattering phenomena strongly depend on the incident angle and polarization of the incident light. To reduce the scattering loss in LPS's, a multilayer with flat layer boundaries is fabricated with rf bias sputtering. As a result, the insertion loss of the LPS is reduced to ~ 1 × 10(-3) dB/ µm, which is acceptable for practical uses.
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Takeda K, Shiraishi K, Fujiki M, Kondo M, Morigaki K. Photocreated metastable states in polysilanes. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:5171-5179. [PMID: 9976855 DOI: 10.1103/physrevb.50.5171] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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228
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Shiraishi K, Maki T. Quantum fluctuation of stress tensor and black holes in three dimensions. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 49:5286-5294. [PMID: 10016846 DOI: 10.1103/physrevd.49.5286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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229
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Shiraishi K, Yaekashiwa M, Nakagawa J, Isawa T, Motomiya M. Application of an air-filled tube for measuring intraesophageal pressure. J Appl Physiol (1985) 1994; 76:2106-13. [PMID: 8063674 DOI: 10.1152/jappl.1994.76.5.2106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We devised a new method for measuring esophageal pressure (Pes) with use of a flexible tube without a balloon at a constant rate of airflow through the tube into the esophagus (balloonless method). A study with 133Xe showed that the air that accumulated in the esophagus did not interfere with the measurement of Pes. We measured dynamic compliance (Cdyn) and pulmonary resistance (RL) with the balloonless method in 19 subjects and obtained a static deflation pressure-volume curve (P-V curve) in 10 other subjects. Cdyn was 0.243 +/- 0.099 l/cmH2O and RL was 1.52 +/- 0.42 cmH2O.l-1.s. In 6 of the 10 subjects, a P-V curve was also obtained with the balloon tube (balloon method). K, the index of compliance in the exponential function V = V0(1-e-KP) where V0 is volume at infinite pressure, was 0.136 +/- 0.040 cmH2O-1 with the balloonless method and 0.153 +/- 0.023 cmH2O-1 with the balloon method. No statistically significant difference was found between these two values. In conclusion, Cdyn, RL, and the P-V curve can be obtained precisely with the balloonless method.
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230
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Natori H, Tanaka K, Shiraishi K, Osabe S, Jojima H, Honda J, Matsuo K, Nakashima O, Oizumi K. Hodgkin's disease in a patient with neurofibromatosis. Am J Hematol 1994; 45:349. [PMID: 8178810 DOI: 10.1002/ajh.2830450419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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231
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Natori H, Tanaka K, Shiraishi K, Osabe S, Jojima H, Oizumi K, Ishibashi M. Lung perfusion scanning in two patients with malignant histiocytosis. Am J Hematol 1994; 45:268-9. [PMID: 8296802 DOI: 10.1002/ajh.2830450317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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232
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Ishizuka Y, Pollak CP, Shirakawa S, Kakuma T, Azumi K, Usui A, Shiraishi K, Fukuzawa H, Kariya T. Sleep spindle frequency changes during the menstrual cycle. J Sleep Res 1994; 3:26-29. [PMID: 10607105 DOI: 10.1111/j.1365-2869.1994.tb00100.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Five healthy adult women aged 20 to 28 had 12-15 polysomnographic recordings, as well as daily basal body temperature and multiple LH, FSH, estrogen and progesterone measurements taken during a single menstrual cycle. Sleep stages were scored both visually and with a spindle and delta-wave, real-time, automatic analysing system. A cubic growth-curve model showed that the frequency of sleep spindles changed markedly over the menstrual cycle: spindle frequency was lowest about 18 days before onset of menses and highest 3 days before onset of menses. Slow waves did not change. The percentages of Stage 1 and REM sleep showed small changes during the menstrual cycle, and other parameters of visually scored sleep showed no tendency to change. Spindle frequency may reflect the effects of sex hormones on the reticular thalamic nucleus and may be a quantitative marker of premenstrual sleep disturbances.
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233
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Shiraishi K, Yamamoto M, Yoshimizu K, Igarashi Y, Ueno K. Daily intakes of alkaline earth metals in Japanese males. HEALTH PHYSICS 1994; 66:30-35. [PMID: 8253575 DOI: 10.1097/00004032-199401000-00004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Diet samples were collected for two duplicate portion studies and one market basket study. 226Ra in the diet samples was determined by alpha spectrometry and daily intake was estimated as 23 mBq (0.62 pCi) per person. Other alkaline earth metals were determined by inductively coupled plasma atomic-emission spectrometry. Average mineral intakes of calcium, magnesium, strontium, and barium were 0.55 g, 0.21 g, 2.3 mg, and 0.39 mg, respectively. Element ratios magnesium:calcium 0.38, strontium:calcium 4.2 x 10(-3), barium:calcium 7.1 x 10(-4), and 226Ra:calcium 1.1 x 10(-12) were found in the diet; these compared with element ratios in Japanese vertebrae of magnesium:calcium 0.1:1, strontium:calcium 3.1 x 10(-4), barium:calcium 2.7 x 10(-5), and radium:calcium 2.6 x 10(-14). Observed ratios, defined as the element ratio in bone divided by the respective element intake ratio in Japanese males, were as follows: 226Ra 0.02, magnesium 0.03, strontium 0.07, and barium 0.04.
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234
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Shiraishi K, Watanabe M, Itakura M, Matsuzaki S, Ishida H. Influence of plasma composition on erythrocyte filtrability in alcoholic liver disease. ALCOHOL AND ALCOHOLISM (OXFORD, OXFORDSHIRE). SUPPLEMENT 1994; 29:1-4. [PMID: 9063807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The influence of plasma components (albumin, fibrinogen, total cholesterol, and triglyceride) on erythrocyte deformability (filtrability) was evaluated by the filtration method. The examinations were carried out using erythrocyte suspensions in HEPES buffer and patient's own plasma, and the respective values were compared in each case. Erythrocyte filtrability in the buffer and in patient's plasma was found to be decreased significantly in alcoholic liver disease. The change in rate of erythrocyte filtrability in own plasma was found to be increased. The concentrations of triglyceride (r = 0.52, P < 0.01) and fibrinogen (r = 0.56, P < 0.01) in plasma of alcoholic liver disease correlated significantly with the change in rate of erythrocyte filtrability. Blood viscosity of patients with alcoholic liver disease was impaired by both the decreased deformability of erythrocytes and the changes in plasma composition (triglyceride and fibrinogen). It was suggested that the change in blood viscosity may disturb sinusoidal blood-flow, resulting in perturbation of the metabolic functions of the liver.
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235
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Kanemitsu Y, Ogawa T, Shiraishi K, Takeda K. Visible photoluminescence from oxidized Si nanometer-sized spheres: Exciton confinement on a spherical shell. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:4883-4886. [PMID: 10008983 DOI: 10.1103/physrevb.48.4883] [Citation(s) in RCA: 183] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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236
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Shiraishi K, Muramatsu Y, Nakajima T, Yamamoto M, Los IP, Kamarikov IY, Buzinny MG. Radionuclide contents in environmental samples as related to the Chernobyl accident. J Radioanal Nucl Chem 1993. [DOI: 10.1007/bf02219856] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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237
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Tanaka K, Honda J, Shiraishi K, Osabe S, Jojima H, Matsuo K, Koga K, Yasuda K, Masuchi K, Imamura Y. [Usefulness of polymerase chain reaction (PCR) technique in making early diagnosis and treatment of cytomegalovirus and Pneumocystis carinii-pneumonia in patients with hematological neoplasms]. [RINSHO KETSUEKI] THE JAPANESE JOURNAL OF CLINICAL HEMATOLOGY 1993; 34:613-9. [PMID: 8391091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Recently, the incidence of opportunistic infections in patients with hematological neoplasms has been markedly increasing. However, early and definitive diagnosis and treatment of these infections remain difficult. In this study, we report three patients, a 47-year-old female with ATL, a 54-year-old female with CML and a 65-year-old female with ATL. All these cases were complicated with pneumonia caused by Pneumocystis carinii (Pc) or cytomegalovirus (CMV). They were successfully treated with sulfamethoxazole/trimethoprim or ganciclovir after detection of the respective microorganisms from sputum samples in the early stage of the infections by polymerase chain reaction (PCR) method. The above clinical evidence demonstrated the PCR technique to be a rapid and sensitive diagnostic procedure for the detection of Pc or CMV and to be helpful for the early initiation of appropriate treatment of the infections in patients with hematological neoplasms.
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238
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Takayanagi I, Kokubu N, Shiraishi K. Inhibitory effect of pilocarpine on norepinephrine release from electrically stimulated iris dilator muscles of rabbits as a most possible mechanism of pilocarpine-induced miosis. J Smooth Muscle Res 1993; 29:55-61. [PMID: 8318730 DOI: 10.1540/jsmr.29.55] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Instillation of pilocarpine-induced a miosis in a rabbit. In an isolated iris sphincter muscle of rabbit, pilocarpine induced a small contraction and behaved as an antagonist of carbachol. The contractile response of an isolated rabbit dilator muscle to a field stimulation was inhibited by pilocarpine. This inhibitory action of pilocarpine was antagonized by atropine in a concentration-dependent manner. An amount of norepinephrine released from the electrically stimulated dilator muscle was inhibited by pilocarpine. The inhibitory effect of pilocarpine on norepinephrine release was decreased by atropine. A following explanation is proposed as a most possible mechanism for the pilocarpine-induced miosis in the rabbit. Pilocarpine activates the prejunctional cholinoceptors to inhibit norepinephrine release from the adrenergic nerve in the dilator muscle. Thus pilocarpine decreases tonus of the dilator muscle and induces the miosis.
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239
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Abstract
Zinc, a trace element, is epileptogenic in rats and rabbits. Its distribution in the CNS is mainly localized in the hippocampus, where kainate (KA) can develop neuronal damage with limbic seizures. We examined the zinc neurotoxicity int he rat brain with KA. The unilateral intracarotid artery infusion of zinc chloride seemed to enhance the specific binding of KA at the ipsilateral hippocampus in the method of receptor-binding autoradiography. Actually, the zinc infusion followed by the intravenous injection of KA 0.5 mg-1 kg-1 body weight induced ipsilateral neuronal damage at the cortex and the CA3-4 of the hippocampus. A potent non-N-methyl-D-aspartate (NMDA) antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) could not change KA binding, but could partially prevent that neuronal damage. According to these results, we consider that zinc administration through intracarotid infusion can enhance the KA neurotoxicity in its binding activities and that CNQX is potent to decrease KA neurotoxicity in the KA insulted area in the rat brain.
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240
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Singtripop T, Mori T, Shiraishi K, Park MK, Kawashima S. Age-related changes in gonadotropin, prolactin and growth hormone levels with reference to the development of uterine adenomyosis in female SHN mice. In Vivo 1993; 7:147-50. [PMID: 8364165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The patterns of serum FSH, LH, PRL and GH levels in SHN mice were determined by radioimmunoassay between 1 and 12 months of age. In addition, the incidence of spontaneous development of uterine adenomyosis and mammary tumor was also studied for 12 months. Serum FSH level increased gradually with age while the level of LH was almost constant during the observation period. On the other hand, concentrations of PRL and GH significantly increased with age. The present data showed that the development of adenomyosis and mammary tumor rapidly increased after 6 and 9 months of age, respectively. Pituitary grafting at 30 days of age resulted in a high incidence of adenomyosis after 6 months of age. There were no significant differences in FSH and LH levels between mice with and without pituitary grafting. However, pituitary grafting resulted in the increase in PRL and GH levels compared with age-matched controls. These findings altogether suggest that the spontaneous development of adenomyosis in SHN mice may be related to the elevation in PRL and GH levels as a function of age.
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241
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Shiraishi K, Matsuzaki S, Ishida H, Nakazawa H. Impaired erythrocyte deformability and membrane fluidity in alcoholic liver disease: participation in disturbed hepatic microcirculation. ALCOHOL AND ALCOHOLISM (OXFORD, OXFORDSHIRE). SUPPLEMENT 1993; 1A:59-64. [PMID: 8141924 DOI: 10.1093/alcalc/28.supplement_1a.59] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The erythrocyte deformability, membrane fluidity, mean corpuscular volume (MCV), and lipid compositions of erythrocyte membrane were investigated to evaluate the possible role in disturbed hepatic microcirculation in alcoholic liver disease. Erythrocyte deformability was assessed in 37 alcoholic patients and 20 normal subjects. Erythrocyte deformability determined by the filtration method was found to be decreased significantly in alcoholic patients. Erythrocyte membrane fluidity in alcoholic liver disease analysed by fluorescence recovery time after photobleaching was decreased significantly. The decrease of erythrocyte membrane fluidity in alcoholic patients correlated significantly with a decrease of erythrocyte deformability (r = -0.65, P < 0.02). The increased MCV in alcoholic liver disease also correlated with a decrease of erythrocyte deformability significantly (r = 0.652, P < 0.02). The lipid compositions of erythrocyte membrane were abnormal in alcoholic liver disease; the phosphatidylcholine:sphingomyelin ratio was increased (P < 0.001) and unsaturated:saturated fatty acid ratio was decreased (P < 0.01). We conclude that, in alcoholic liver disease, the decreased erythrocyte deformability was closely associated with changes of membrane fluidity and MCV. It was also associated with abnormalities of membrane lipid compositions. It is speculated that these abnormalities of erythrocytes result in further reduction of sinusoidal blood flow in alcoholic liver disease, and consequently disturb metabolic functions of the liver.
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242
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Abstract
We performed sonography in 7 males with membranous and posterior urethral calculi. Sonography demonstrated the urethral calculi in all 7 patients. These findings suggest that sonography is useful as a noninvasive screening technique for urethral calculi.
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243
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Shiraishi K, Takayanagi I. Subtype of muscarinic receptors mediating relaxation and contraction in the rat iris dilator smooth muscle. GENERAL PHARMACOLOGY 1993; 24:139-42. [PMID: 8482487 DOI: 10.1016/0306-3623(93)90024-r] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
1. Carbachol produced a relaxation of dilator muscle at a concentration lower than 1 microM and a contraction at a concentration higher than 1 microM. 2. We studied the effects of the M1-selective antagonist, pirenzepine, the M2-selective antagonist, himbacine, the M3-selective antagonist, 4-diphenyl-acetoxy-N-methylpiperidine methiodide (4-DAMP) and the non-selective antagonist, atropine, on carbachol-induced relaxation and contraction of the rat iris dilator smooth muscle. All the antagonists competitively inhibited both the responses to carbachol. 3. In relaxation and contraction, the low affinity of pirenzepine and himbacine suggest that the rat iris dilator smooth muscle receptors are not of the M1 and M2 subtypes. In contrast, 4-DAMP potently inhibited the carbachol-induced relaxation and contraction with affinities similar to those reported for the M3 subtype. 4. Carbachol-induced relaxation and contraction of the rat iris dilator appears to be mediated through a homogeneous population of M3 subtype.
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244
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Xu Y, Shiraishi K, Mori M, Motomiya M. Changes of fibronectin in the right and left ventricles of rats exposed to chronic normobaric hypoxia. TOHOKU J EXP MED 1992; 168:573-82. [PMID: 1306605 DOI: 10.1620/tjem.168.573] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Changes of fibronectin (FN) in the right and left ventricles of adult rats exposed to chronic normobaric hypoxia were observed by a peroxidase immunohistochemical stain technique and analyzed quantitatively by a point counting method. Fifty-six rats were randomly divided into control groups of day 0 (immediately prior to the experiment), day 5, day 15, and day 30 and hypoxia groups of day 5, day 15, and day 30. Rats of the hypoxia groups were put into a normobaric hypoxia chamber with oxygen concentration adjusted to 10 percent. The rats of the control groups breathed room air. From day 5 on, the ratio of the weight of the right ventricle (RV) to that of the left ventricle (LV) plus interventricular septum (SP), RV/(LV+SP), and the ratio of the weight of the right ventricle (RV) to the body weight (BW), RV/BW, in the hypoxia groups increased significantly as compared with those of the control groups. The amount of immunoreactive FN in the right ventricle increased significantly in the hypoxia groups after exposure to hypoxia environment for 15 days (10.31% +/- 2.15%, mean +/- S.D.) and for 30 days (9.55% +/- 1.65%) as compared with those in the day 0 control group (3.05% +/- 1.15%, p < 0.01), the day 15 control group (3.26% +/- 0.83%, p < 0.01), and the day 30 control group (3.19% +/- 0.51%, p < 0.01). However, there were no significant changes in the amount of immunoreactive FN in the left ventricle of the hypoxia groups as compared with the control groups. These results suggest that chronic hypoxia may lead to an increase of FN in the hypertrophied right ventricle but not in the left ventricle, which indicates that pulmonary hypertension induced by chronic hypoxia rather than chronic hypoxia itself is a major cause for the increase of FN in the myocardium. The increased FN in the right ventricle may accelerate the accumulation of collagen and, in turn, contribute to the increase of the myocardial stiffness and eventually to the diastolic dysfunction of the hypertrophied right ventricle induced by chronic hypoxia.
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245
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Matsumoto M, Arafune J, Tanaka H, Shiraishi K. Solutions of the renormalization-group equations for minimal supergravity SU(5) grand unified theory and strong constraints on its parameters. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1992; 46:3966-3980. [PMID: 10015353 DOI: 10.1103/physrevd.46.3966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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246
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Ohno T, Shiraishi K, Ogawa T. Intrinsic origin of visible light emission from silicon quantum wires: Electronic structure and geometrically restricted exciton. PHYSICAL REVIEW LETTERS 1992; 69:2400-2403. [PMID: 10046475 DOI: 10.1103/physrevlett.69.2400] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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247
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Shiraishi K, Moriya M, Miyake N, Takayanagi I. Alpha1-adrenoceptor blocking activities of bevantolol hydrochloride(NC-1400) and labetalol in rat isolated thoracic aorta—Do they distinguish between subtypes? GENERAL PHARMACOLOGY: THE VASCULAR SYSTEM 1992; 23:843-5. [PMID: 1358746 DOI: 10.1016/0306-3623(92)90235-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
1. alpha 1-adrenoceptor blocking activity of bevantolol(NC-1400) was tested in the rat thoracic aorta, comparing with that of labetalol. 2. In alpha 1-adrenoceptor blocking activity, bevantolol(NC-1400) was 1/20th as potent as labetalol. 3. The pA2 values of bevantolol(NC-1400) and labetalol estimated in the rat thoracic aorta were compared with those in the rabbit thoracic aorta, which were reported by Takayanagi et al. [Takayanagi I., Kizawa Y., Iwasaki S. and Nakagoshi A. (1987) Gen. Pharmac. 18, 87-89]. 4. The pA2 values of bevantolol(NC-1400) and labetalol were approximately 1 order of magnitude higher in rat aorta than in rabbit aorta, suggesting that both the drugs distinguish between subtypes of alpha 1-adrenoceptors.
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MESH Headings
- Adrenergic beta-Antagonists/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Labetalol/pharmacology
- Male
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiology
- Norepinephrine/antagonists & inhibitors
- Norepinephrine/pharmacology
- Propanolamines/pharmacology
- Rabbits
- Rats
- Rats, Wistar
- Receptors, Adrenergic, alpha/metabolism
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248
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Takayanagi I, Shiraishi K, Kokubu N. Alpha 1B-adrenoceptor mechanisms in rabbit iris dilator. JAPANESE JOURNAL OF PHARMACOLOGY 1992; 59:301-5. [PMID: 1331586 DOI: 10.1254/jjp.59.301] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Rabbit isolated iris dilator strips were contracted by norepinephrine, an alpha 1A- and alpha 1B-nonselective agonist, but not by methoxamine, an alpha 1A-selective agonist. The concentration-response curve for norepinephrine was considerably inhibited by chloroethylclonidine. The pA2 values for WB4101 and 5-methylurapidil were 8.16 +/- 0.09 and 7.84 +/- 0.08 (means +/- S.E. of 8-12 experiments), respectively, and significantly smaller than the values reported in the rat renal artery and thoracic aorta, and rabbit bronchus, where the alpha 1A-subtype is predominant. These results suggest that the rabbit iris dilator contains primarily the alpha 1B-subtype. Clonidine and tizanidine did not contract the rabbit iris dilator but shifted the curve for norepinephrine in a parallel manner, suggesting that they interact with the alpha 1B-subtype and act as competitive antagonists in this muscle. Methoxamine (up to 10(-3) M) had no effect on the contractile response to norepinephrine, suggesting that methoxamine does not interact with the alpha 1B-subtype.
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249
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Xu YJ, Abe T, Shiraishi K, Motomiya M. Effect of chronic hypoxia on fibronectin in plasma, bronchoalveolar lavage fluid and liver of rats. JOURNAL OF TONGJI MEDICAL UNIVERSITY = TONG JI YI KE DA XUE XUE BAO 1992; 12:107-11. [PMID: 1433417 DOI: 10.1007/bf02887791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The present study was undertaken to measure fibronectin (FN) concentration in plasma and bronchoalveolar lavage fluid (BALF) with an enzyme linked immunosorbent assay (ELISA) method, to observe the distribution of FN in liver with an immunohistochemical stain method and to investigate the effect of chronic normobaric hypoxia on them in experimental rats. The results showed that chronic hypoxia caused a significant decrease in plasma FN concentration while BALF FN concentration and the distribution of FN in the liver were not significantly affected, suggesting that the change in FN in the lower respiratory tract can not be reflected by the change in plasma FN concentration and that the decrease in plasma FN concentration can not be attributed to the change in liver FN secretion. The decrease in plasma FN concentration may lead to a decrease in the defence ability of the body and may contribute to the development of hypercoagulability observed in some patients with chronic hypoxia.
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250
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Takayanagi I, Shiraishi K, Satoh M. Effects of ageing on responses of rabbit iris smooth muscles to agonists and field stimulation. GENERAL PHARMACOLOGY 1992; 23:463-9. [PMID: 1324868 DOI: 10.1016/0306-3623(92)90112-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
1. The pharmacological properties of contractile responses of sphincter and dilator to field stimulation did not change with age, so that innervation of both these muscles does not change apparently with age. 2. In the sphincter, no age-related change was observed in muscarinic cholinoceptor mechanisms. Tension induced by field stimulation increased with age from 5 to 13 weeks, decreased from 40 to 125 weeks and did not change thereafter. Age-related change in tension is due to change in the amount of acetylcholine released by stimulation. 3. In the dilator, the pD2 value of norepinephrine increased with age from 5 to 13 weeks, decreased from 13 to 125 weeks and did not change thereafter. The pD2 value of norepinephrine was proportional to the receptor reserve, suggesting that changes in alpha 1-adrenoceptor mechanisms are due to changes in receptor reserve. No age-related change was observed in affinity of alpha 1-adrenoceptors. 4. The tension of the dilator induced by field stimulation increased with age from 5 to 13 weeks did not change from 13 to 180 weeks. The age-related change in tension is due to change in the amount of norepinephrine released by stimulation.
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