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961.
GJ Dagnall 《Canadian Metallurgical Quarterly》1993,37(1-2):45-52
The colonial morphology and other cultural characteristics of Branhamella ovis were studied. The current investigation showed that colonies could be designated R (rough) and S (smooth) dependent on their appearance on agar. The colonial variants were apparently stable and each produced distinct types of pitting when grown on agar. A CAMP-like reaction was also shown to be a characteristic of B. ovis. 相似文献
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965.
N.S. McIntyre D. Johnston W.J. Chauvin W.M. Lau K. Nietering D. Schuetzle K. Shankar J.E. Macdonald 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,12(3):389-395
Multilayer thin films containing silver and copper, sandwiched in a metal oxide, have been depth profiled by secondary ion mass spectrometry (SIMS) using primary ions of differing mass, energy and chemical reactivity. These results were compared for accuracy with those obtained by Rutherford backscattering spectrometry (RBS). The use of O2+ or O? as primary ions resulted in severe distortion of the silver ion intensity distribution in the SIMS profile of a ZnO/Ag/ZnO thin film on glass; O2+ bombardment at energies from 3–10 keV resulted in the detection of silver at the glass interface, while the use of O? caused the silver to be detected closer to the outer surface than expected from RBS results. Primary beams of Ar+ and Xe+ gave progressively more accurate results for the Zn/Ag/Zn distribution; Xe+ at 5.0 keV energy produced profiles that agreed within 10% of RBS-derived values. The same beam conditions, used to profile a double silver layer in ZnO, resulted in some discrepancy in the position of the inner layer, compared to RBS results, and this was attributed to an enhanced sputter rate in the oxide under the outside metal film. Depth profiling of TiO2/Cu/TiO2 films with oxygen also resulted in significant distortion of the perceived position of the metal layer, and this was again significantly improved using Xe+ primary ions of 6–9 keV energy. The distorting effects of oxygen bombardment can be understood in terms of a migration of metal ions in an electrostatic field created by a charged surface. Ionization of the metallic layer is enhanced by the use of oxygen. By contrast, the use of rare gases reduces the production of ions from the metallic layer which can migrate prior to the onset of sputtering. 相似文献
966.
Degradative cytosolic proteolysis contributes to cell injury following ATP depletion. Although ATP depletion is a salient feature of ischemic liver storage for transplantation, information regarding cytosolic protease activity during liver storage is lacking. Thus our aim was to measure liver cytosolic protease activity following ischemic storage. A progressive increase in total cytosolic protease activity was observed over time at both 37 degrees C and 4 degrees C, but the increase was greater at 37 degrees C. Total cellular proteolysis was also temperature-dependent during anoxia (37 degrees C > 4 degrees C), demonstrating a physiologic correlation between cellular proteolysis and measurements of cytosolic protease activity. The stimulation of total cytosolic protease activity was due to an increase in metallo- and aspartate protease activity. Of particular interest, glutathione (GSH) inhibited both metalloprotease and aspartate protease activity from cytosol of stored livers. Glycine, the carboxyl-terminal amino acid of GSH, also inhibited both metalloprotease and aspartate protease activity. In addition to being an antioxidant, GSH may exert its protective effects during organ preservation by inhibiting cytosolic proteases--perhaps via its glycine moiety. These experiments support the hypothesis that degradative proteolysis contributes to liver injury during organ preservation. 相似文献
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968.
GF Peaslee MB Tsang C Schwarz MJ Huang WS Huang WC Hsi C Williams W Bauer DR Bowman M Chartier J Dinius CK Gelbke T Glasmacher DO Handzy MA Lisa WG Lynch CM Mader L Phair MC Lemaire SR Souza Van Buren G RJ Charity LG Sobotka GJ Kunde U Lynen J Pochodzalla H Sann W Trautmann D Fox de Souza RT G Peilert WA Friedman N Carlin 《Canadian Metallurgical Quarterly》1994,49(5):R2271-R2275
969.
The biocompatibility of a 3 mm band made of polyethylene terephthalate (Trevira hochfest) has been tested in an experimental study within right knee joints of 60 sheep. After transsecting the anterior cruciate ligament (ACL), two randomized groups were formed. In group I, the ACL was repaired according to the Marshall technique whilst in group II an additional 3 mm polyethylene terephthalate (PET) augmentation band was implanted using the through-the-condyle (TTC) procedure. To assess the biocompatibility of the augmentation device the knee joints of both groups were punctured and the synovial fluids were analyzed before, as well as 2, 6, 16, 26, and 52 weeks after the operation. In addition, the histologic appearance of excised suprapatellar pouches and ipsilateral inguinal and popliteal lymphatic noduli were examined. Comparing both groups no significant differences were found neither before nor after the augmented and non-augmented ACL repair. No pathological increase in the total protein concentration occurred after operation and no significant differences versus the preoperative analysis were found. No synovitis signalling a decrease in the glucose concentration was observed. The cytological examination revealed no increase of the leukocyte cell count results. Within the synovial specimen neither free nor phagocytosed PET wearparticles could be detected. In groups I and II the histological appearance of excised popliteal and inguinal lymphatic noduli showed a normal result. In 25% of the PET augmented ACL repairs, a slight concentration of PET wearparticles and solitary, multinuclear giant foreign body cells could be seen in the histological preparations of suprapatellar pouches. 相似文献
970.
The results of liver function tests and ultrasonographical findings were analysed in 7 dogs that were intravenously injected dimethylnitrosamine (DMNA 2 mg/kg body weight) on 2 consecutive days each week for 10 weeks. Typical clinical signs and similar changes in liver enzyme concentrations that develop in dogs with natural cirrhosis were observed in this canine model. Severe anaemia and a significant reduction in the platelet numbers occurred in the dogs that died in the 5th week, while in all the other dogs these parameters decreased slightly. Serum total protein and the albumin/globulin ratio decreased gradually while the alkaline phosphatase, alanine amino transferase, aspartate amino transferase and gamma glutamyl transpeptidase activities increased significantly (p < 0.05) in all dogs after beginning the administration of DMNA. Ultrasound findings of a coarsened and heterogeneous echo pattern with increased echogenicity that are characteristic of canine cirrhosis were noticed at the same time when the changes in liver enzymes became evident. Present results suggest that ultrasonography in conjunction with liver function tests may be useful in the evaluation of experimentally induced liver cirrhosis. 相似文献