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101.
1. The aqueous extract of Salviae Miltiorrhizae radix (Chinese crude drug named "dan-shen") relaxed the noradrenaline-precontracted aorta with endothelium. 2. Vasodilation by the extract disappeared in aorta without endothelium, and was inhibited by pretreatment with 10(-4) M NG-monomethyl-L-arginine (L-NMMA) or 10(-5) M methylene blue. 3. The inhibition of the extract-induced vasodilation by L-NMMA was reversed by L-arginine (3 x 10(-4) M). 4. The component of the extract was analyzed by chromatography, fast atom bombardment mass spectroscopy (FAB-MS) and 1H-NMR. 5. An active component of the extract, which showed endothelium-dependent vasodilation, was found to be identical with lithospermic acid B.  相似文献   
102.
103.
New integration technique for grating-imaging-type encoder is proposed and the sensor for the encoder has been fabricated using Si micromachining technology. The sensor consists of the Si grids and line photodiodes. The light emission through the Si grids and the light detection with the four-phase-shifted line photodiodes make the optical system compact. Moreover, another photodiode array of the M-series arrangement is installed on the same substrate for the zero-point detection.  相似文献   
104.
The effect of conditioning stimulation of the central amygdaloid nucleus (ACE) on the response of tooth pulp-driven (TPD) neurons in the first somatosensory cortex (SI) was investigated in cats anesthetized with N2O-O2 (2:1) and 0.5% halothane. The tooth pulp test stimulus was a single 30-450 microA rectangular pulse, and the conditioning stimuli of the ACE were trains of 33 pulses (300 microA) delivered at 330 Hz. The ACE conditioning stimulation markedly suppressed the response of the slow-type neurons with latencies of more than 20 ms without any effect on the discharges of fast-type TPD neurons and spontaneous discharges. This inhibition was 68.9 +/- 24.7% (mean +/- SD) of the control. These findings suggest that there are at least two pathways for the ascending pulpal (nociceptive) information to the SI, and that the ACE modulates the transmission of impulses in one of the pathways.  相似文献   
105.
106.
Printable nonvolatile memory devices have been attracting considerable interest because of their application to flexible large-area devices. In order to fabricate such memory devices, it is necessary to discover a new ferroelectric material and to develop an efficient process for its preparation. We have previously reported that poly(γ-methyl-L-glutamate) (PMLG) functions as a ferroelectric layer of an organic thin-film transistor (OTFT) memory device [S. Uemura, A. Komukai, R. Sakaida, M. Yoshida, S. Hoshino, T. Kodzasa, T. Kamata, Synth. Met. 153 (2005) 405]. Further, ferroelectricity is observed when α-helical PMLG molecules are aligned in a direction parallel to the film surface. In this study, we investigate the effect of the tertiary structure of PMLG molecules on the hysteresis of OTFT memory devices, i.e., memory performance. From the results, we conclude that the hysteresis of the OTFT is strongly affected by the helical tertiary structure of PMLG molecules, similar to the structure of a cholesteric liquid crystal phase.  相似文献   
107.
Defect structures in crystallites of the stable phases in thin films of transition-metal (TM) disilicides (C11 b MoSi2, C40 TaSi2, and C54 TiSi2) produced by cosputtering and subsequent annealing have been investigated by transmission electron microscopy (TEM). Crystallites in thin films of MoSi2, TaSi2, and TiSi2 all contain planar faults parallel to hexagonally arranged TMSi2 planes, which are a characteristic feature commonly observed in all three crystal structures. These planar faults are twin boundaries in all cases. Twins in thin films of these disilicides, thus, have a common characteristic that the twin habit plane is parallel to hexagonally arranged TMSi2 stoichiometric planes. For twins in thin films of C11 b MoSi2, and C54 TiSi2, the twining elements can be deduced and the twin habit plane is found not to be parallel to the twinning (K 1) plane, but to be perpendicular to it. Twins formed in C40 TaSi2 thin films are different from those formed in C11 b MoSi2 and C54 TiSi2 thin films, in that the crystal orientation of the twin is exactly the same as that of the matrix, since they are racemic twins that are only enantiomorphically (space groups of P6222 or P6422) related to each other. This article is based on a presentation in the symposium “Terence E. Mitchell Symposium on the Magic of Materials: Structures and Properties” from the TMS Annual Meeting in San Diego, CA in March 2003.  相似文献   
108.

Objectives

This study aims to investigate the effect of collagen matrix impregnated with bone marrow on wound healing angiogenesis in an effective microcirculatory model and to describe our clinical experience.

Methods

We used a skinfold chamber of original design which visualises microcirculation following wound creation on the dorsal skin of the mouse to establish an in vivo experimental model to estimate angiogenesis. Animals were divided into two groups: a bone marrow group (n=6) in which bone marrow-impregnated collagen matrix was applied to the wound; and a control group (n=7), in which collagen immersed in saline was applied, and functional capillary density was quantified during the repair process.

Results

The increase rate in functional capillary density during wound healing significantly increased in the bone marrow group on days 3, 5 and 7 after creation of the wound but no significant difference was detected on day 10. A patient with a chronic leg ulcer that had not responded to conventional therapy for 1 year was treated with autogenous bone marrow-impregnated collagen matrix and successful wound closure was obtained.

Conclusion

The present study suggested that collagen matrix impregnated with bone marrow significantly promoted the repair process, especially in the early stage. The features of the treatment, including the possible use of a patient's own cells, simple method, immediate application without any processing procedure and preservation of the inclusive potentiality of bone marrow suspension, offer significant advantages in terms of the anticipated routine clinical use.  相似文献   
109.
A total of 11 cases of papillary muscle dysfunction (PMD) was found among 600 consecutive autopsy (1.8%). There were 5 men and 6 women, with their ages ranging from 64 to 92 years. Auscultation and phonocardiograms revealed holosystolic murmurs in 9 cases and early systolic murmurs in 2. There were accentuated 1st sound in 8 cases, 3rd sound in 7, and 4th sound in 5. PMD was classified into 3 types according to the clinical course and pathologic examinations. In type A (6 cases), myocardial infarction (MI) preceded the occurence of mitral regurgitation (MR) by 3 or 4 years, with pathological verification of old MI. In type B (1 case), MR developed during acute MI. In type C (4 cases), pathological examinations disclosed various degrees of myocardial fibrosis, in which clinical diagnosis was MR of unknown etiology. In a total of 113 cases of MI, 36 cases (32%) showed papillary muscle infarction (PMI), which occurred with significantly high incidence in (1) male, (2) large MI, and (3) subendocardial or lateral MI. Among 36 cases of PMI, 9 cases developed PMD, which showed high incidence in inferior MI and in female. Various other factors concerning PMD and PMI were examined, and it was pointed out that not only PMI but also severe lesions in corresponding ventricular wall were necessary for the development of PMD.  相似文献   
110.
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