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Simplified procedure for preparation of35S-labeled brain sulfatide   总被引:1,自引:0,他引:1  
A simplified procedure for the preparation of35S-labeled brain cerebroside sulfates has been developed. The labeled sulfatides are synthesized in vivo after intracerebral administration of inorganic35S-sulfate in developing rats. The animals are sacrificed three days later and brain homogenates extracted with chloroform-methanol. The extract is subjected to mild alkaline treatment and washed with water. The organic phase is chromatographed on triethylaminoethyl-cellulose from which sulfatides are eluted with chloroform-methanol containing potassium acetate. Radioactive fractions are pooled, concentrated, and potassium acetate removed by dialysis against water. Alternatively, salts are removed by passing radioactive fractions through Sephadex G-25. After evaporating to near dryness, the radioactive cerebroside sulfates are dissolved in a small volume of chloroform-methanol and stored at −20 C. The35S-sulfatides are essentially free of lipid contaminants, and 97% of the radio-activity corresponds with sulfatides on chromatographic analysis.  相似文献   
3.
To investigate and evaluate the micro-pool mechanism in a mixed lubrication regime using polybutene lubricants, experiments were performed using 1 mm brass sheet, for various surface rough nesses of a work piece and die, lubricant viscosities and extrusion speeds. Systematic study showed that (1) the lower viscosity lubricant is easily squeezed out from the micro-pools into the flat are a through the troughs between the tool and work piece caused by plastic deformation of work piece, and (2) with decrease in lubricant viscosity and speed, or the larger the tool surface roughness becomes, the more lubricant infiltrates into the tool-work piece interface, which reduces the actual friction coefficient.  相似文献   
4.
A fuel irradiation program is being conducted using the experimental fast reactor ‘Joyo’. Two short-term irradiation tests in the program were completed in 2006 using a uranium and plutonium mixed oxide fuel which contains minor actinides (MA-MOX fuel). The objective of the tests is the investigation of early thermal behavior of MA-MOX fuel such as fuel restructuring and redistribution of minor actinides. Three fuel pins which contained MA-MOX: 2% neptunium and 2% americium doped uranium plutonium mixed oxide (Am,Pu,Np,U)O2−x fuel were supplied for testing. The first test was conducted with high-linear heating rate of approximately 430 W cm−1 for only 10 min. After the first test, one fuel pin was removed for examinations. Then the second test was conducted with the remaining two pins at nearly the same linear power for 24 h. In these tests, two oxygen-to-metal molar ratios were used for fuel pellets as a test parameter. Non-destructive and destructive post-irradiation examinations results are discussed with early on the behavior of the fuel during irradiation.  相似文献   
5.
A distributed feedback (DFB) laser emitting at 1.3 μm for gigabit lightwave communication systems has been developed. The distributed feedback structure has been introduced in a newly developed buried heterostructure and designs for stable single-mode operation, high speed modulation, and low noise have been done. Threshold current of 10-15 mA, differential efficiency of around 0.28 mW/mA, low noise, small signal modulation bandwidth of 13.9 GHz, and satisfactory modulation waveform at 5-Gbit/s NRZ modulation have been attained with high single-mode operation yield.  相似文献   
6.
Steel corrosion under atmospheric conditions is a critical issue in the maintenance of structures such as electric transmission towers and bridges during their long-term operation, which are generally located at many places over a wide area. Since a major factor causing corrosion is airborne salt particles coming from the sea, wide-area distributions of the long-term cumulative amount of sea salt deposited on surfaces are needed. Moreover, since the amount of airborne sea salt varies locally with the topography, it is also important to consider the effects of topography. In this paper, a method combining a computational fluid dynamics model and a statistical procedure is proposed to efficiently estimate wide-area distributions of the cumulative amount of airborne sea salt by considering the local topography. The predicted amount of airborne sea salt decreases with increasing distance from the coast and varies with the topography and the offshore wind. A comparison between predicted and observed amounts revealed that: (1) this method appropriately estimates topographical effects on sea-salt transport and enables the estimation of deposited sea salt on structure surfaces, and (2) consideration of the trapping efficiency of sea-salt particles on structure surfaces improves the prediction accuracy.  相似文献   
7.
The reduction of energy consumption has become the global task in recent years as a countermeasure to address the global warming issue caused by the mass discharge of carbon dioxide. The volume of carbon dioxide emission from automobiles has become approximately 21 % of the total emission by volume, so improved fuel efficiency is strongly urged and the development and application of new technologies have been actively implemented; the technologies required to reduce the weight of the automobile body, in particular, has attracted a much attention.1 Amongst these, aluminium alloys have a high strength for their light weight and have superior recycling properties, so the move to reduce the automobile body weight by replacing the existing materials with aluminium alloys has progressed rapidly and totally aluminium alloy automobiles have now become commercially available.2  相似文献   
8.
Some stereoblind observers do not perceive depth of 3D stimuli that depends on binocular disparity. These individuals, who have no disabilities, comprise over 5% of the general population. In addition, 17–30% of nonstereoblind young and young–middle people do not use disparity information in certain 3D environments, a phenomenon known as pseudo‐stereoblindness. This study aimed to investigate the relationship between aging and the proportion of pseudo‐stereoblindness in the general population. In an experiment, 134 nonstereoblind participants, ranging in age from 17 to 83 years, judged subjective depth of 3D stimuli containing binocular disparity and pictorial depth cues. Results showed that the proportion of pseudo‐stereoblindness among young (17–24 years old) and young–middle aged observers (25–39 years old) was 29%, in both cases. However, the proportion of pseudo‐stereoblind observers increased in older populations: 65% and 82% in the middle (40–54 years old) and senior (55–83 years old) age groups, respectively. These results suggest that a number of people, especially in elderly populations, have trouble perceiving depth from binocular disparity in 3D graphic contents despite their essential ability to use disparity information.  相似文献   
9.
Two patients with inflammatory breast cancer treated with a combination of radical mastectomy, irradiation, and immunochemotherapy are reported. After radical mastectomy, both patients were given a dose of 4000 rad and 5000 rad to the chest wall and parasternal lymph nodes, and 5000 rad to the axillary and supraclavicular lymph nodes. However, both patients died of recurrence within the irradiated field of the chest wall and metastatic spread to the neighbouring skin. A discussion on the dose and field in radiation therapy for inflammatory breast cancer is presented.  相似文献   
10.
STUDY OBJECTIVE: To determine whether an association exists between individual anesthesiologists and nonpatient care time in the operating room (OR). DESIGN: Retrospective chart review. SETTING: Cardiac surgery operating theatre in a University Hospital. PATIENTS: 312 elective coronary artery bypass procedures over 2 years. MEASUREMENTS AND MAIN RESULTS: The time interval between cases, as defined by the time between the first patient out and the second patient in, was compared. Six anesthesiologists, labelled 1 to 6, were involved in the 156 data points analyzed. The mean (+/- SD) time interval between cases, in minutes, for anesthesiologists 1 to 6 were, respectively: 24 +/- 9, 25 +/- 8, 27 +/- 8, 29 +/- 5, 30 +/- 4, 31 +/- 7. The difference among the anesthesiologists' mean time interval between cases was significant (p < 0.01). The mean time interval between cases was significantly different between anesthesiologists 1 and 6 (p < 0.01) and between anesthesiologists 2 and 6 (p < 0.05). CONCLUSION: The impact of a shorter time interval between cases on OR efficiency remains unknown. Further education and investigation of this issue are warranted.  相似文献   
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