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981.
An reinsten Eisen-Stickstoff-Legierungen mit rd. 0,015% N Untersuchung des Einflusses der Temperatur von 500 bis 800 °C, des Wasserstoffdruckes von 150 bis 760 Torr und der Probendicke im Bereich von 0,22 bis 0,60 mm auf die Geschwindigkeit der Entstickung durch trockenen strömenden Wasserstoff. 相似文献
982.
We propose two-well founded orderings on multisets that extend the Dershowitz-Manna ordering. Unlike the Dershowitz-Manna ordering, ours do not have a natural monotonicity property. This lack of monotonicity suggests using monotonicity to provide a new characterization of the Dershowitz-Manna ordering. Section 5 proposes an efficient and correct implementation of that ordering. 相似文献
983.
Alberto Schiraldi 《Electrochimica acta》1978,23(10):1039-1043
As a result of electronic microscopy observations the amorphous nature of the high conductivity AgIAg oxysalt electrolytes seems due to a random orientation of structurally ordered microdomains having less than 1 micron size. A tentative approach to the structure of these domains is suggested in order to account for (i) the fast silver ion migration, which would occur along “smooth” passageway tracked by iodide ions, (ii) the critical composition, vis 80 mole% AgI, corresponding to the conductivity maximum found for most of these materials at room temperature, (iii) the low activation energy of the conductivity Arrhenius plots, (iv) the presence of some immobile Ag+ which closely surround the oxyanions. 相似文献
984.
985.
986.
Three patients with painful malunions of the scaphoid and significant loss of active wrist extension were treated with an opening wedge multiplanar osteotomy that corrected flexion, ulnar deviation, and pronatory rotational malalignment of the distal fragment. After a minimum follow-up of 4 years, all three patients were satisfied with the procedure and were pain-free. The preoperative range of wrist motion had improved, and they had returned to their preoperative occupations. 相似文献
987.
J Fernández Aguila O Crombet Ramos R Pons Vázquez 《Canadian Metallurgical Quarterly》1998,43(5):406-414
The major factors underlying the seeding of tumor cells during laparoscopy are mechanical, with CO2 playing only a secondary role. The peritoneal wound is of great importance, especially in advanced tumor stages, when cells are present within the abdominal cavity. Most reported port-site metastases were found within the extraction port when no protective measures were taken. Gasless laparoscopy is no solution to the problem, since numerous port-site metastases have been described after thoracoscopy, during which no C02 is used. The surgeon's role in the seeding of tumor cells is based on tumor perforation, excessive manipulation, and replacement of trocars. This presumably explains the large differences (0% and 21 %) in the reported incidence of port-site metastases. Prospective studies now show that it is possible to keep the incidence of abdominal wall metastases to about 1%-which is comparable to that seen in open surgery-by the use of a meticulous operating technique and preventive measures. 相似文献
988.
OBJECTIVE: To study the relationship between glutathione S-transferase mu (GST mu) gene deletion and senile cataract (SC) susceptibility. METHOD: Polymerase chain reaction (PCR) method was used to investigate the rates of GST mu gene deletion in 59 cases with SC and 112 healthy controls. RESULTS: The rate of GST mu gene deletion in cases with SC was 69.5% which was significantly higher than that of the controls, 50.9% (P < 0.05). An analysis stratified by smoking and nonsmoking showed that GST mu gene deletion rate in smoking subjects with SC was higher. Because of the small sample size of this study, although the rate of GST mu gene deletion in smoking subjects with SC has reached 72.4%, that is not significantly different from that of the controls statistically (P > 0.05). CONCLUSION: SC correlates with GST mu gene deletion and GST mu gene deletion is one of the hereditary factors for susceptibility to SC. 相似文献
989.
990.