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991.
H Tatar S Ci?ek U Demirkili? E Ozal H Süer O Oztürk H I?iklar 《Canadian Metallurgical Quarterly》1993,55(3):659-661
Among various pharmacological agents used to reduce bleeding after open-heart operations, high-dose aprotinin therapy seems most promising. However, its long-term effects are still obscure; there is almost always possibility of bypass graft occlusions produced by the hypercoagulable state induced by aprotinin in coronary bypass operations. Topical application of aprotinin into the pericardial cavity could prevent the adverse effects. Fifty patients were prospectively studied to evaluate the effects of topical aprotinin. One million KIU of aprotinin was poured into the pericardial cavity before closure of the sternotomy in group 1 (n = 25). Patients in group 2 (n = 25) served as controls. Total postoperative bleeding was significantly reduced in group 1 when compared with that of group 2 (722.7 +/- 230.8 versus 1,282.6 +/- 225.7 mL; p < 0.01). The use of banked donor blood products was significantly less in group 1 than in group 2 (0.33 +/- 0.67 versus 1.36 +/- 0.86 units; p < 0.01). These results show that topical use of aprotinin reduces post-operative blood loss and need for transfusion. It seems promising and warrants further studies to be done. 相似文献
992.
993.
AB Thomson N Chiba D Armstrong G Tougas RH Hunt 《Canadian Metallurgical Quarterly》1998,12(8):551-556
Gastroesophageal reflux disease (GERD) is a disease with serious consequences that may result in significant impairment in quality of life and disease morbidity. Across all grades of severity of symptoms and severity of underlying esophageal disease, proton pump inhibitors (PPIs) provide therapeutic gains over prokinetics (PKs) or H2 receptor antagonists (H2RAs). The potential cost effectiveness of using medications with higher acquisition costs that may lower health care costs overall is often disregarded when conducting cost comparisons with medications having lower 'up-front' costs. Limiting therapy to less effective agents condemns many patients to protracted suffering, repeated physician visits and needless reinvestigation of symptoms that could have been resolved by appropriate initial therapy. Based on current data, use of any classification of symptom severity as a basis for selecting one class of therapeutic agents over another for first line therapy (i.e. PKs, H2RAs for 'mild' GERD, versus a PPI for 'severe' disease) is unwarranted. 相似文献
994.
A Fassati A Bardoni M Sironi DJ Wells N Bresolin G Scarlato M Hatanaka S Yamaoka G Dickson 《Canadian Metallurgical Quarterly》1998,9(17):2459-2468
995.
Hepatic and pancreatic effects of polyenoylphosphatidylcholine in rats with alloxan-induced diabetes
V Buko O Lukivskaya V Nikitin Y Tarasov L Zavodnik A Borodinsky B Gorenshtein B Janz KJ Gundermann R Schumacher 《Canadian Metallurgical Quarterly》1996,14(2):131-137
In neonatally allylestrenol treated animals in adult age a single benzpyrene treatment significantly decreases the female and significantly increases the male rat's sexual activity. Three month old females display the negative sexual behavioral effect of neonatal allylestrenol treatment less than the six month old ones. The benzpyrene treatment in adult age decreases the sexual activity of male rats. The experiments call the attention to the modifying effect of perinatal steroid treatments to similar exposure in adult age. 相似文献
996.
The properties of glasses of the lithium-aluminoborosilicate system were investigated, namely, the density, spreadability, thermal expansion, and nature of crystallized phases at various temperatures. A crystal-optical analysis was conducted. The glasses were used to prepare abrasive compositions. Their strength properties were studied as a function of the composition of the glass binder and the regime of heat treatment.Translated from Steklo i Keramika, No. 3, pp. 27–30, March, 1996. 相似文献
997.
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 71–86, May–June, 1995. 相似文献
998.
Measurements of the scattering cross section of a number of bare soils have been made with CO2 laser illumination at 10.59 μm. The primary focus was on absolute calibration of the measurements. First, comparison of emissivity values resulting from the application of Kirchhoff's relation after angular integration of the bidirectional measurements, with emissivity values obtained from the analysis of the emitted radiation show excellent agreement to within less than 0.3%. Second, it was found that a simple formula holds for a relationship between the emissivity and co- and cross-polarized backscattering cross section at an angle of 30°. Third, a clear correlation was observed between emissivity and composition (in this case % Al+Fe oxides; % SiO2) for a homogeneous series of samples from the same area in Niger. These results emphasize the importance of calibrated experimental data. The implications of the research give evidence of the advantage of obtaining emissivity from remote reflectivity measurements and possibly only backscattering measurements, and remotely estimating mineral composition 相似文献
999.
Schubert E.F. Hunt N.E.J. Malik R.J. Micovic M. Miller D.L. 《Lightwave Technology, Journal of》1996,14(7):1721-1729
Resonant-cavity light-emitting diodes (RCLED) are novel, high-efficiency light-emitting diodes which employ optical microcavities. These diodes have higher intensities and higher spectral purity as compared to conventional LEDs. Analytical formulas are derived for the enhancement of the spontaneous emission along the optical axis of the cavity. The design rules for high-efficiency operation of RCLEDs are established. The temperature dependence of the emission intensity is analyzed in the range 20-80° and it is described by an exponential dependence with a characteristic temperature of 112 K. The modulation characteristics of RCLEDs exhibit 3 dB frequencies of 580 MHz. Eye diagrams at transmission rates of 622 Mb/s are wide open indicating the suitability of RCLEDs for high-speed data transmission 相似文献
1000.
G. Meaden P. G. Partridge M. N. R. Ashfold E. D. Nicholson A. Wisbey 《Journal of Materials Science》1996,31(11):2801-2805
Continuous chemical vapour-deposited diamond-coated fibres with tungsten wire or SiC fibre cores are attractive for reinforcing metals and ceramics. The fibres have been embedded in Ti-6A1-4V alloy to produce a diamond fibre-reinforced composite. Both the fibres and the composite material are extremely difficult to cut without damage by conventional mechanical methods. The use of a Nd-YAG laser to cut these materials is described. 相似文献