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991.
JR Bourbon 《Canadian Metallurgical Quarterly》1976,155(3):713-715
Dihydrofolate reductase activity did not change with variations of mitotic rate in foetal rabbit haemopoietic tissue, whereas the activity of thymidylate synthetase declined with decrease in cell divisions. Both the activities were normal in the brachydactylia strain, in which a failure in folate metabolism was previously assumed. 相似文献
992.
Comparison of mortality of patients with heart attacks admitted to a coronary care unit and an ordinary medical ward 总被引:2,自引:0,他引:2
During a 32-month period 2047 patients suspected of having heart attacks were admitted to hospital and were followed up prospectively. Out of 1480 eventually found to have definite or probable myocardial infarction, 483 had initially been admitted to an ordinary medical ward because of the shortage of coronary care unit (CCU) beds. More patients aged over 65 had been admitted to a ward than to a CCU, and more patients aged 65 or less had been admitted initially to a CCU. Within each age group, however, patients admitted initially to a CCU were clinically similar to those admitted initially to a ward. There was a higher proportion of successful resuscitations among patients admitted to a CCU, but there was no significant difference in mortality in either age group between patients admitted to a CCU and a ward. 相似文献
993.
JR Buck WH Weintraub AG Coran ML Wyman LR Kuhns 《Canadian Metallurgical Quarterly》1977,12(3):451-463
Transillumination (TI) is a safe and reliable technique for evaluating masses or the presence of free air in the thorax or abdomen. TI can also be of help in the accurate placement of catheters or needles in the chest, abdomen, bladder, or vessels. Its use in several hundred cases has been documented by this report. 相似文献
994.
The appearance of prostaglandins in dog's blood during endotoxin-induced hypotension was studied by use of the dialysis modification of the blood bathed organ technique. An increase in prostaglandins, mainly E2 and F2alpha was found in renal venous blood, whereas no such increase was seen in blood from the abdominal aorta, the inferior vena cava or the femoral vein. Three possible trigger mechanisms for this increase i.e. hypotension, reduced flow and reflexogenic sympathetic stimulation, have been investigated. It is suggested that, in addition to these three factors, circulating hormones such as noradrenaline, angiotensin or bradykinin, play a role in this release mechanism. Administration of indomethacin produced a restoration of the systemic blood pressure to its pre-endotoxin value; concomitantly a disappearance of the prostaglandins from the circulation was observed. It is concluded that prostaglandins contribute to the hypotension induced by endotoxin. Whether they are beneficial or detrimental remains to be resolved. 相似文献
995.
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
996.
997.
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
998.
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
999.
1000.