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991.
The present study was undertaken to ascertain the feasibility of using a 25-gauge needle for arterial punctures. A total of 11,500 arterial punctures were performed over the past four years by this technique without any major complication. Repeated arterial punctures were well tolerated by all patients, and the necessity for indwelling arterial catheters was almost totally eliminated during this period of study. 相似文献
992.
993.
l一ltroduetlon Hydrogenation of earbon monoxide to form 11ydroearbons and aleollols 15 usually carriedout over iron and cobalt catalysts.In Germany during World War 11,cobalt eatalysts wereused to Produce some of the liquid fuels required by the country f… 相似文献
994.
The conjugation of 1-p-chlorophenyl-4,4-dimethyl-5-diethylamino-1-penten-3- one hydrobromide (CDDP), a Mannich base of an alpha,beta-unsaturated ketone, to glutathione is catalyzed selectively by alpha-class glutathione S-transferase. The reaction of CDDP with glutathione can be monitored continuously by following the conjugation-dependent decrease in absorbance of CDDP at 307 nm. The Km and Vmax for CDDP with alpha-class glutathione S-transferase from horse liver were determined to be 226 microM and 14.6 mumol/(min.mg), respectively. CDDP is the first example of an alpha-class glutathione S-transferase selective substrate that monitors the glutathione conjugation activity, rather than the glutathione peroxidase activity of the enzyme. 相似文献
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997.
The high-low inversion in polycrystalline cristobalite, synthesized from quartz at 1500°C, was investigated by differential thermal analysis to 7 kbar in hydrostatic apparatus. A region of anomalous curvature ( d2 T/dp2 >0) exists to ∼1 kbar; at higher pressure, the low→high and high→low transition temperatures vary linearly with pressure, with slopes of ∼51.1 and 53. 6 deg kbar−1 , respectively. Extrapolated 1-bar intercepts are ∼232° and ∼209°C, respectively. It is concluded that high cristobalite is less compressible than low cristobalite near the inversion. The hysteresis between the high→low and low→high transition temperatures decreases with increasing pressure. 相似文献
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EL Wolf WE Berdon JR Cassady DH Baker R Freiberger H Paviov 《Canadian Metallurgical Quarterly》1977,125(3):781-784
Five cases of slipped femoral capital epiphysis were noted in children with prior irradiation for malignancy whose femoral head and neck had been included in the radiation portal. Three of the 5 were patients who had lymphoma. As a result of increasing survival rates for these types of patients, this previously unrecognized radiation-related growth disturbance may be more likely to be seen in the future. 相似文献