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91.
The authors reported a case of an arteriovenous malformation associated with an aneurysm on its feeding vessel that is the left anterior inferior cerebellar artery. A housewife, aged 56-years, was admitted to our hospital with severe headache, nausea and vomiting. On admission, lumbar puncture revealed grossly bloody CSF. Neurological examination revealed meningeal irritation sign, horizontal nystgmus and disturbance of left auditory acuity. Bilateral carotid and retrograde brachial arteryography revealed an AVM near the left cerebellopontine angle and a small aneurysm of the left anterior inferior cerebellar artery at the left internal auditory meatus. At operation, the aneurysm was wrapped with a muscle piece and no surgical intervention for AVM. Post-operative course was uneventful except for disterbance of the left auditory acuity. Follow-up angiographies revealed a change of size the aneurysm and AVM and finaly failed to demonstrate the aneurysm and AVM demonstrated preoperatively. The spontaneous regression of the AVM might be due to the post-operative brain swelling and adhesion. We also speculated that the spontaneous disappearance of the aneurysm might be due to the decreased blood flow of parent artery by the spontaneous regression of the AVM. It is very rare that an aneurysm of anterior inferior cerebellar artery co-existed with AVM, and resulted in thrombosis of the aneurysm and regression of the AVM after wrapping alone. 相似文献
92.
Partial glyceride mixtures, which include 1-monoglyceride, 2-monoglyceride, free fatty acid, 1,2-diglyceride, 1,3-diglyceride
and triglyceride, could be separated from each other on a 3% boric-acid-impregnated Chromarod S-II (silica gel sintered quartz
rod) with either chloroform/acetone (96∶4, v/v) or chloroform/acetone/acetic acid (100∶1∶1, v/v) as the developing solvent
mixtures. The components separated on the boric-acid-impregnated rod were automatically quantitated in a hydrogen flame ionization
detector (Iatroscan). The relative responses of 1,2-diglyceride, 1,3-diglyceride, free fatty acid and triglyceride were slightly
lower than theoretical responses based on weight percentage, whereas 1-monoglyceride and 2-monoglyceride showed slightly higher
responses. These responses were converged within a maximal error of 5–10% (SD). Boric-acid-impregnated rods could be used
repeatedly, ca. 5 times without any reconditioning procedure.
Part of this investigation was reported at the 2nd JOCS-AOCS joint meeting, San Francisco, May 1979. 相似文献
93.
The authors have conducted a laboratory-scale gallery fire test on eight different samples of electric cable in a horizontal airflow. The number of speciments and the distances between them on the trestle were varied for each test. As a result, it was found that both ignitability and flame-propagation properties depended on the distance between the specimens as well as on their number. Such flammability properties obtained for each cable sample were also found to be considerably consistent with the critical oxygen index. In addition, it is proposed that the flammability should be classified largely into five categories in this laboratory-scale gallery fire test for fire-retardance evaluation of solid combustible materials such as electric cables. 相似文献
94.
95.
Kyogoku K Yoshida K Watanabe H Yamashita T Kawabe Y Motono M Nishijima K Kamihira M Iijima S 《Journal of Bioscience and Bioengineering》2008,105(5):454-459
We previously reported the production of recombinant proteins using genetically manipulated chickens and quails. In this study, we constructed a retroviral vector encoding an expression cassette for a fusion protein of the extracellular domain of the human tumor necrosis factor (TNF) receptor 2 and Fc region of human IgG1 (TNFR/Fc), which is expected as an effective drug for inflammatory diseases such as rheumatoid arthritis. The concentrated viral vector was injected into developing chicken embryos. The chickens that hatched stably produced TNFR/Fc in the serum and egg yolk for six months. It appears that the fused protein is transported and accumulated into yolk from the serum, which is mediated by the Fc receptor. The protein purified from the yolk and serum inhibited the cytotoxic activity of TNF-* toward L929 cells, indicating that the protein produced by the chickens is biologically active. These results indicate the effectiveness of the recovery of Fc-fused proteins from the yolk of genetically manipulated chickens. 相似文献
96.
Seiya Suzuki Takuya Iwasaki K. Kanishka H. De Silva Shigeru Suehara Kenji Watanabe Takashi Taniguchi Satoshi Moriyama Masamichi Yoshimura Takashi Aizawa Tomonobu Nakayama 《Advanced functional materials》2021,31(5):2007038
Germanene, a 2D honeycomb germanium crystal, is grown at graphene/Ag(111) and hexagonal boron nitride (h-BN)/Ag(111) interfaces by segregating germanium atoms. A simple annealing process in N2 or H2/Ar at ambient pressure leads to the formation of germanene, indicating that an ultrahigh-vacuum condition is not necessary. The grown germanene is stable in air and uniform over the entire area covered with a van der Waals (vdW) material. As an important finding, it is necessary to use a vdW material as a cap layer for the present germanene growth method since the use of an Al2O3 cap layer results in no germanene formation. The present study also proves that Raman spectroscopy in air is a powerful tool for characterizing germanene at the interfaces, which is concluded by multiple analyses including first-principles density functional theory calculations. The direct growth of h-BN-capped germanene on Ag(111), which is demonstrated in the present study, is considered to be a promising technique for the fabrication of future germanene-based electronic devices. 相似文献
97.
98.
Takayuki Nakamura Yoshiaki Taguchi Masamichi Ogasa 《Electrical Engineering in Japan》2015,193(2):69-81
To reduce the loss due to ripple current in a multiphase current‐reversible chopper, we investigated electromagnetic coupling of an air‐core reactor. We derived the relationship between the amplitude of the ripple current, the duty factor, and the electromagnetic coupling coefficient, and used the results to estimate the effects of electromagnetic coupling in the design of a train energy storage system. We built reactors with electromagnetic coupling coefficients of 0.93 and 0.60. These reactors employed a new winding structure that provides an optimal electromagnetic coupling coefficient. The mass of the former type of reactor was increased by 4.4% over the conventional design, and that of the latter type of reactor was decreased by 17%. Finally, we tested the new reactors. When the chopper employs the former type of reactor and operates with equal‐phase switching and cumulative coupling, the loss due to ripple current is decreased by 11%. When the chopper employs the latter type of reactor and operates with shift‐phase switching and differential coupling, the loss is decreased to 31%. The test showed that the calculated relationships agreed with the measured values. 相似文献
99.
Masamichi Akimoto Tetsuya Ishii Koji Yamagaki Kazuhisa Ohtaguchi Kozo Koide Kazunaga Yazawa 《Journal of the American Oil Chemists' Society》1990,67(12):911-915
Optimization of culture conditions for the growth rate, 5,8,11,14,17-cis-Eicosapentaenoic acid (EPA) content and EPA productivity of a bacterium isolated from Pacific mackerel intestines was investigated
by use of a culture medium containing 1.00 wt% peptone and 0.50 wt% yeast extract in an artificial sea water (ASW). Cultivation
temperature affected the growth rate and cellular EPA content of the bacterium. The cellular EPA content at 8°C was as great
as 16.8 mg/g of dry cells, which was more than two times greater than that at 25°C (7.3 mg/g of dry cells), although the growth
rate showed a maximum at 25°C. Both the yield of bacterial cells and the cellular EPA content at 25°C reached maximum values
when the pH of the culture medium was nearly 7.0 and when the concentration of ASW was 100% (v/v). Under optimum culture conditions
[25°C pH 7.0 and 100% (v/v) ASW], the amount of EPA accumulated in the cellular lipids reached 45.6 mg/L of culture broth
after 8 hr. 相似文献
100.
Melting kinetics of polymer crystals has been examined experimentally by calorimetric methods utilizing the combination of a conventional differential scanning calorimetry of heat flux type (CDSC-HF) and a temperature-modulated DSC (TMDSC). The superheating effect in the kinetics has been discussed based on a modeling of the melting kinetics. For low-density polyethylene and linear polyethylene, the melting rate showed nearly linear dependence on the degree of superheating, which indicates the kinetics controlled by heat diffusion or by surface kinetics on rough interface. For isotactic polypropylene, poly(ethylene terephthalate) and poly(?-caprolactone), the dependence is non-linear and close to the limiting case of exponential dependence, which indicates nucleation-controlled kinetics of melting. A possible mechanism of the activation process in the melting kinetics has been discussed in consideration of the specific feature of polymer crystals far from its most stable state. The consistency of the results of CDSC-HF and TMDSC has been confirmed by this analysis with a calibration of peak temperature for the instrumental thermal delay in CDSC-HF. 相似文献