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991.
MD el-Zawahry AF Ramzy E el-Sahwi AF Bahnasy M Khafaga MA Rizk-Allah MF Abou el-Hoda 《Canadian Metallurgical Quarterly》1997,132(7):698-702
The history of medicine can never be complete without referral to ancient Egyptian medicine. Imhotep has been identified as the god of medicine. There are 13 faculties of medicine in Egypt; the oldest is the Kasr El Aini Faculty, which started in 1925. We review undergraduate and postgraduate education in Egypt. The Egyptian Society of Surgeons organizes the scientific surgical activities. Schistosomiasis is a national health problem. Health care is provided by many types of hospitals, including university, teaching, Ministry of Public Health, military, and private hospitals. 相似文献
992.
L Bara MF Bloch D Zitoun M Samama F Collignon A Frydman A Uzan J Bouthier 《Canadian Metallurgical Quarterly》1993,69(5):443-452
In a randomized crossover study twelve healthy male volunteers (23.5 +/- of 4.8 years, 73.0 +/- 6.4 kg, 180.8 +/- 5.7 cm) received one subcutaneous injection of either enoxaparin (EN) at 40 mg or 1 mg kg-1, or unfractionated heparin (UH) at 5,000 IU at one week intervals. Area under curves (AUC) of Anti-Xa and Anti-IIa activities correlated with EN dose. The relative effectiveness of EN versus UH 5,000 U as assessed by AUC ratio (EN/UH) was 7 and 15 for Anti-Xa activity, 1.3 and 3.1 for Anti-IIa activity after sc injection of EN 40 mg (4,000 Anti-Xa IU and 1,200 Anti-IIa U) and 1 mg kg-1 (7,300 +/- 640 Anti-Xa IU and 2,190 +/- 290 Anti-IIa IU) respectively. In volunteers receiving EN, a dose dependent inhibition of thrombin generation rate in platelet depleted plasma (PDP), measured with a new and simple chromogenic thrombin generation assay, was observed when compared with baseline values. Similarly, intrinsic prothrombin activation in whole blood, evidenced by measuring residual factor II in serum 2 hours after clotting (prothrombin consumption test: PC), was inhibited in a dose dependent manner. In UH treated volunteers, although the inhibition of thrombin generation rate in PDP was similar to that observed with EN 40 mg, prothrombin consumption in whole blood was not significantly modified. Tissue factor pathway inhibitor (TFPI) activity release was increased similarly for UH and EN 40 (1.4 fold increase above baseline values) and 1.9 fold for the higher dose of EN. The discrepancy between prothrombin consumption in whole blood and inhibition of thrombin generation rate in PDP in the UH and not in the EN group strongly suggests that UH and not EN is influenced by the presence of a platelet component. This could be formed during thrombin induced platelet activation. Platelet factor 4 is a possible candidate. Another hypothesis involves the role of TFPI-UH complex anticoagulant activity which might be inhibited more during whole blood coagulation than the TFPI-EN complex. 相似文献
993.
Patients with sickle cell disease (SCD) are predisposed to infections. There is a paucity of recent information on the incidence of post-splenectomy infectious complications in these patients. The purpose of this study was to determine whether splenectomy increases infectious complications in SCD. Twenty-nine patients with SCD had splenectomy for sequestration crises at our hospital between 1988 and 1992; 16 of them received all of their follow-up care at our institution. These 16 charts were reviewed for infectious-related admissions, hospital days, days of i.v. antibiotics, positive cultures, and episodes of sepsis. For each patient, these parameters in the pre- and postoperative period were compared and expressed as number per year. The mean age at time of splenectomy was 2.5 +/- 0.4 years and the mean follow-up was 4.5 +/- 0.4 years. There was no significant difference in the pre- and postoperative periods for admissions, hospital days, days of i.v. antibiotics, positive cultures, or episodes of sepsis per year. There were also no operative deaths. The incidence of pre-splenectomy sepsis was 0.04 +/- 0.03 episodes per year compared to 0.09 +/- 0.04 (P = ns) episodes/year after splenectomy. Sepsis occurred at an average of 20.8 (range 2-30) months postoperatively; Streptococcus pneumoniae was the most common causative organism. The total mortality after splenectomy in SCD patients was 3.4% (1/29) over a nearly 5-year period. Although infections are common in children with SCD, there was no increase in infections or episodes of sepsis in SCD patients who underwent splenectomy. 相似文献
994.
Gastric tonometer PCO2 measurement may help identify gut ischemia in critically ill patients but is frequently associated with large measurement errors. We tested the hypothesis that small bowel tonometer PCO2 measurement yields more accurate information. In 10 anesthetized, mechanically ventilated pigs subject to progressive hemorrhage, we measured gut oxygen delivery and consumption. We also measured tonometer PCO2 minus arterial PCO2 (DeltaPCO2) and calculated the corresponding intracellular pH from tonometers placed in the stomach and jejunum. We found that the correlation coefficient (r2) for biphasic gut oxygen delivery-DeltaPCO2 relationships was 0.29 +/- 0.52 for the gastric tonometer vs. 0.76 +/- 0.25 for the small bowel tonometer (P < 0.05). In addition, the critical gastric tonometer DeltaPCO2 was excessively high and variable (62.9 +/- 39.6) compared with the critical small bowel tonometer DeltaPCO2 (17.0 +/- 15.0, P < 0.01). Small bowel tonometer PCO2 was closely correlated with superior mesenteric vein PCO2 (r2 = 0.81, P < 0.001), whereas gastric tonometer PCO2 was not (r2 = -0.13, P = not significant). We conclude that measurement of gastric tonometer PCO2 yields excessively noisy and inaccurate data on the onset of gut anaerobic metabolism in hemorrhagic shock. Small bowel tonometer PCO2 is less noisy and, as a result, is superior in detecting gut hypoperfusion and the onset of anaerobic metabolism. 相似文献
995.
996.
997.
Fast-rate otoacoustic emissions (OAEs) were used to determine the inward and outward transmission change produced by the stapedial muscle reflex. The subjects were otologically normal adult volunteers. Satisfactory recordings were obtained from a total of 16 ears. Runs of 16 click-evoked OAEs were recorded at a rate of 4282 clicks/s using the maximum length sequence (MLS) technique, with a contralateral tone presented at 10 dB above the contralateral acoustic reflex threshold during the recording of OAEs 5-12 in each run. The OAEs recorded with the contralateral tone were compared with those recorded without the tone to determine the effect of the acoustic reflex. An analysis of the OAEs in 0.5 kHz frequency bands suggested that the reflex produced significant attenuation of low frequency sound with smaller effects at high frequencies, which included amplification for some subjects. For eight of the 16 ears there was an increase in OAE amplitude with the acoustic reflex for at least one frequency band. At low frequencies (1, 1.5 kHz) the inward transmission change produced by the acoustic reflex appeared to be similar in magnitude to the outward transmission change. 相似文献
998.
Nicolas Y Njintang Mary L Parker Graham K Moates Carl MF Mbofung Andrew C Smith Keith W Waldron 《Journal of the science of food and agriculture》2006,86(6):902-907
The functional properties of flour and the organoleptic, rheological and microscopic characteristics of traditionally made achu were compared with those of reconstituted achu prepared from the taro variety Ibo coco. Organoleptic analyses showed that reconstituted achu was generally softer in consistency and less appreciated than traditional achu. In general with respect to functional properties, the estimated water absorption capacity, bulk density, blue value index and penetrometric index were lower for traditional achu than for reconstituted achu. In contrast, the viscosity of traditional achu was significantly higher than that of reconstituted achu. Light microscopic observations revealed that reconstituted taro achu is a smooth starch gel containing broken parenchyma cells whereas in traditional achu, the paste is mainly composed of whole cells within a starch gel. Coulter particle size analyses of achu showed a peak at median 122 µm for traditional achu whereas reconstituted‐flour achu had its median at 143 µm. All the functional, rheological and microscopic analyses reflect the higher degree of starch gelatinisation in the reconstituted achu. From this study, it is suggested that boiling the whole corms before drying could improve the texture of the reconstituted achu. Copyright © 2006 Society of Chemical Industry 相似文献
999.
Relative in vitro stability of ornithine decarboxylase from liver preneoplastic nodules and hepatomas 总被引:1,自引:0,他引:1
A very rapid and drastic microsome-dependent in vitro inactivation of the hydrocortisone-induced ornithine decarboxylase in rat liver was reported recently (M. F. Zuretti and E. Gravela, Biochim. Biophys. Acta. 742: 269-277, 1983). Present results show that ornithine decarboxylase from preneoplastic nodules and hepatomas, which have been induced in rats by N-2-fluorenylacetamide, is much more stable, its greater stability not being accounted for by a lower microsome-bound inactivating capacity. The possibility of a relationship between the in vitro enzyme stability and the increase of enzyme activity in neoplastic tissues is suggested. 相似文献
1000.
C Wu MF Chan F Stavros B Raju I Okun S Mong KM Keller T Brock TP Kogan RA Dixon 《Canadian Metallurgical Quarterly》1997,40(11):1690-1697
Previously we reported the discovery of amidothiophenesulfonamides as endothelin receptor-A antagonists with high potency and selectivity. Replacement of an amide group in this class of compounds with an acetyl group maintained the in vitro binding affinity and in vivo activity while providing a compound with oral bioavailability and longer duration of action. The optimal compound discovered during these studies, 15q (TBC11251), binds competitively to human ETA receptors with a Ki of 0.43 +/- 0.03 nM and an IC50 of 1.4 nM (IC50 for ETB = 9800 nM). This compound inhibits ET-1-induced stimulation of phosphoinositide turnover with a Ki of 0.686 nM and a pA2 of 8.0. The compound has a serum half-life in the rat and the dog of 6-7 h and 60-100% oral bioavailability. This compound is one of the most selective ETA antagonists reported and therefore is suitable for additional pharmacological and clinical investigation of the role of ETA receptors in diseases. 相似文献