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51.
H Yamanaka T Motohiro T Michiura A Asai T Mori K Hioki 《Canadian Metallurgical Quarterly》1998,46(10):943-948
A direct differentiation of the internal and external drug-deposition pattern into hair was made using two fluorescent dyes and fluorescence microscopy after systemic administration to mice or external exposure of untreated hair. Mice (23 days old, C57 and Balb/C) were administered either rhodamine or fluorescein intraperitoneally at varied doses on 3 consecutive days of 3 weeks, and hair was sampled 1 week later. Another group was given 10 mg/kg rhodamine or 100 mg/kg fluorescein and sampled at time points from 5 min to 168 hr. The time courses of external deposition of rhodamine and fluorescein into untreated hair were examined after hair was soaked in 0.1 mg/ml solutions at pH 3, pH 6, and pH 9 aqueous buffer or methanol. The hair was then extracted in pH 6 phosphate buffer or methanol for 24 hr. In vivo accumulation was distinguishable as fluorescent bands along the length of the hair for rhodamine and fluorescein. The pattern of in vivo deposition appears to arise from the rapid accumulation within the cortex and medulla, with little deposition evident in the cuticle. Neither phosphate buffer nor methanol washes affected the intensity of fluorescence in the hair. External loading of rhodamine into the hair resulted in staining of the junctions of cuticle scales. This pattern persisted even after 12 hr of solution exposure. Extraction with pH 6 phosphate buffer or methanol did not remove rhodamine. Fluoroscein followed a similar pattern, with maximum fluorescence when hair was loaded in pH 6 100mM phosphate buffer and nominal staining when loaded in pH 9 100 mM Tris buffer or methanol. Soaking the hair in pH 6 buffer, but not methanol, removed some fluorescein. These results demonstrate that compounds in the circulation can rapidly diffuse into the forming cortex and medulla, where rapid associations occur with elongating intermediate filaments specific to the medulla and cortex. These compounds can become significantly occluded within the mature matrix and are resistant to removal in aqueous or methanolic solutions. 相似文献
52.
The Quantum Functional Device (QFD) project started in fiscal year (FY) 1991 as a ten-year project. The mission of this QFDs project is to develop novel devices for information processing which control quantum phenomena to realize low power consumption, and high-speed and multi-functional operation. The participants in this project are the Electrotechnical Laboratory, five universities, and eight private companies, including two US and UK companies. 相似文献
53.
Y Ono H Manki K Yoshimura T Muramatsu H Mizushima S Higuchi G Yagi S Kanba M Asai 《Canadian Metallurgical Quarterly》1997,74(5):501-503
Only five cases of paraganglioma of the prostate have been reported hitherto. The tumours may be functional (phaeochromocytomas) or non-functional and benign or malignant. We present a sixth case--a non-functional, benign paraganglioma of the prostate--with a review of the literature. 相似文献
54.
The effect of a single dose of morphine (50 mg/kg) and ethanol (2 g/kg) on total magnesium content in blood serum, brain, heart, lung, kidney, liver, femoral muscle and spleen in mice was studied. Significant decrease of magnesium serum concentration was observed after morphine and ethanol administration but not after both drugs given simultaneously. Morphine caused the evident decrease of magnesium content in brain, lung, kidney and muscle, while it was elevated in heart and spleen and unchanged in liver. Ethanol produced significant decrease of magnesium content in heart, lung and kidney and it's increase in liver and spleen. Concomitant administration of both drugs was connected with the diminished amount of magnesium in heart, lung, kidney and muscle and led to the rising of magnesium content in spleen. It is concluded that even a single dose of investigated drugs is sufficient to produce promptly some risk of alterations in magnesium homeostasis. 相似文献
55.
BACKGROUND: The aim of this study was to determine the mechanism by which the calcium channel promoter BAY y 5959 affects the control of heart rate and baroreflex sensitivity in conscious dogs with pacing-induced heart failure (HF). METHODS AND RESULTS: We compared responses to BAY y 5959, which increases inotropy and decreases chronotropy, with those to norepinephrine (NE), which coincidentally exerts the same directional effects on inotropy and chronotropy, albeit through different mechanisms, in the presence and absence of ganglionic blockade both in control and in HF. Both BAY y 5959 and NE elicit direct effects on the heart and indirect effects through activation of reflexes, primarily the sinoaortic baroreceptor reflex. BAY y 5959 still reduced heart rate in dogs with arterial baroreceptor denervation, but not after ganglionic blockade. HF induced classic catecholamine desensitization to the inotropic effects of NE and blunted reflex bradycardia. In contrast, inotropic responses to BAY y 5959 were preserved in HF. Surprisingly, the autonomically mediated bradycardia induced by BAY y 5959 was also preserved in HF. Baroreflex sensitivity was assessed in control and in HF by pulse interval-systolic arterial blood pressure (PI/SAP) slopes constructed in response to pharmacological alterations in arterial pressure. HF depressed the PI/SAP slope from 11.5+/-1.3 to 4.8+/-0.9 ms/mm Hg, but during BAY y 5959 infusion in HF, the PI/SAP slope was restored to 24.1+/-5.2 ms/mm Hg. To assess central versus peripheral actions of BAY y 5959, the agent was infused with intra-carotid artery perfusion at a low dose, which acted centrally but did not have an effect peripherally. Under these conditions, it still decreased heart rate and restored baroreflex sensitivity (PI/SAP slope, 12.7+/-2.8 ms/mm Hg). CONCLUSIONS: Thus, the calcium promoter restores arterial baroreflex sensitivity in HF. Based on intra-carotid artery experiments, this occurs through a central nervous system and vagal mechanism. 相似文献
56.
It has been reported that serum levels of thrombomodulin (TM) reflect endothelial damages in various diseases. We measured serum TM levels between day-10 and day 100 in 6 patients receiving allogeneic bone marrow transplantation. Serum TM levels were increased when patients had transplant related complications including graft versus host disease, hemorrhagic cystitis and interstitial pneumonitis. In patient without complications, serum TM levels were within normal limits. These results suggest that the serum TM level serves as a useful marker of treatment related toxicity and a predictor of complications after BMT. 相似文献
57.
The discharge behaviour of electrodeposited lead dioxide and lead electrodes was investigated under various conditions; the surfaces of the discharged electrodes were observed with a scanning electron microscope. Both the positive and negative electrodes were passivated by a covering of deposited lead sulphate crystals. The amount of lead sulphate required for passivation depended on the size of the crystals. 相似文献
58.
AC Galloway SB Colvin EA Grossi MA Parish AT Culliford T Asai NM Rofsky JC Weinreb S Shapiro FG Baumann 《Canadian Metallurgical Quarterly》1993,105(5):781-8; discussion 788-90
During an 8-year period (1984 to 1991) 66 patients (mean age 59 years, range 26 to 84 years) with type A aortic dissection (60 ascending aorta tears, 6 arch tears; 35 acute, 31 chronic) had surgical repair by a continuous suture-graft inclusion technique. Hypothermic circulatory arrest (16 degrees C) was used in 58 patients (35/35 acute, 23/31 chronic; mean arrest time 26 minutes, range 10 to 55 minutes). Fifty-two patients had hemiarch repair and 6 had total arch replacement. Aortic valve disease necessitated treatment in 38 patients (1 valved conduit, 20 valve replacements, 17 valve repairs). Recently 11 patients had valve repair by reconstruction of the native aortic root, by means of techniques similar to those used for homograft valve insertion. Operative mortality was 9% (14% acute, 3% chronic). Stroke occurred in 2 patients (3%) and was fatal in both. Variables suggestive of increased operative risk by univariate analysis were acuteness (p = 0.12), visceral ischemia (p = 0.12), and preoperative shock (p = 0.13). No variable was significant by multivariate analysis. Overall actuarial survival at 48 months was 77%, with 3 late deaths from a ruptured distal aneurysm. Late computed tomography or magnetic resonance imaging scan was done in 28 patients at a mean interval of 33 months. These studies identified 1 patient with a pseudoaneurysm requiring reoperation and 3 patients with contained flow between the graft and the wrap. Three patients required late operation: 1 for pseudoaneurysm, 1 for arch dissection, and 1 for repair of a distal aneurysm. 相似文献
59.
T. Inagaki Y. Doi H. Hirabayashi Y. Kato K. Kawano H. Sato S. Sugimoto K. Takamatsu E. Takasaki T. Tsuru H. Yoshimura O. Asai T. Satow 《低温学》1984,24(2):83-89
Benkei, which was a large window frame conventional magnet at KEK has been converted to a superconducting magnet. In the conversion, the pole gap has been doubled from 0.5 m to 1.0 m retaining an analysing power at 2 T m. Several new techniques were applied to coil windings and cryostat fabrication. The superconducting Benkei has shown satisfactory performances for long term operation. 相似文献
60.
Quaternary AlGaInAs quantum-well optical modulators operating at 1.55 μm are introduced and demonstrated for the first time. An electron-to-heavy-hole exciton absorption peak shift of over 600 Å is observed for a bias voltage of 6 V. An extinction ratio of 19 dB and high-speed operation over 4 GHz is obtained for this optical modulator 相似文献