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81.
The aims of this study were to examine a prototype battery operated wax-knife, assess the extent to which manufacturer's claims have been achieved and determine its potential for clinical use. The mean time required for the wax-knife to achieve an operating temperature of 150 degrees C was 20.2(+/-4.3) s. The mean operating temperature of the ceramic blade was 155.4(+/-3.9) degrees C, range 150 degrees C to 162 degrees C. The mean usage time following full battery recharge was 42 (+/-2) minutes. The wax-knife provided a direct heating tool which retained many of the characteristics of the traditional wax-knife and was suitable for use in the surgery and in domiciliary situations. 相似文献
82.
SD Walter SE Birnie LD Marrett SM Taylor D Reynolds J Davies JJ Drake M Hayes 《Canadian Metallurgical Quarterly》1994,84(3):367-376
OBJECTIVES: Our objectives were (1) to describe an analysis of the spatial pattern of cancer incidence in Ontario and (2) to discuss the quality of data in the Ontario Cancer Registry with respect to the accuracy of local cancer rates. METHODS: Cancer incidence rates were calculated for 22 cancer sites in 49 counties of Ontario during 1976 to 1986. Capture-recapture methods were used to estimate completeness of case registration, and completeness of residence information was also assessed. Spatial autocorrelation was used in measuring the geographic pattern of incidence rates. Comparisons were also made between sexes and with earlier data from 1966 to 1975. RESULTS: The quality of the geographic data in the registry appeared good, and corrections for incomplete or inaccurate registration had little impact. About one third of the sex-site combinations showed some evidence of spatial patterning in the cancer rate. Particularly strong regional variation was noted for cancers of the stomach, lung, uterus, and prostate. CONCLUSIONS: The analysis revealed a number of cancers with significant spatial patterning of risk. Further work is needed to relate the cancer data to other information on potential life-style and environmental factors. 相似文献
83.
Using the Gleeble 1500, incremental and continuous hot compression tests, simulating hot rolling, were performed on C-Mn, Nb-T, and Nb steels with test temperatures varying between 875 and 1100°C and strain rates between 0.5 and 20 s?1. Four models are proposed. The stress peak model allows the prediction of continuous stress-strain curves from incremental curves and vice versa through the use of stress restoration index K. Variation in K for Nb-T1, C-Mn and Nb steels at strain rates of 3, 12 and 20 s?1 was found to be negligible. The predicted stress strain curve corresponds to experimental stress strain curve at same temperature and strain rate. The strain history model predicts continuous strain-time curves from incremental stress-strain curves using ‘constant’ ‘negative strain’ restoration index. At 950°C, with holding time 2 s and strain rate 12 s?1, strain time decay curves obtained for C-Mn, Nb and Nb-T, steels were ε = 1.5e?05t, ε = 1.2e?0.36t and ε = e?0.3t, respectively. The creep model analysis relates creep strain rate to the testing strain rate. For Nb steel at 875°C, and test strain rate of 12 s?1, ?creep was found to be 9.5 s?1. The stress history model predicts continuous stress-time curves from incremental stress-time curves. Stress decay curve for C-Mn steel at 1100°C and ? = 3s?1 was found to be σ = 181e?0.04t. Hot rolling characteristics of steels can be accurately predicted using hot compression tests and proposed models. 相似文献
84.
85.
D. S. Wood J. Wynn C. Austin J. G. Green 《Fatigue & Fracture of Engineering Materials & Structures》1988,11(5):371-381
Abstract— A limited number of long term creep/fatigue tests performed on two batches of Type 316 steel and one batch of associated 17Cr8Ni2Mo weld metal are reported. Test durations range from 5000 to 32,000 h and temperatures from 5.50 to 625 ° C. Subsequent metallographic examination shows the failures to be wholly or predominantly intergranular. The results are analysed using a ductility exhaustion approach and it is shown that the endurances obtained are within a factor of two of predicted values. The results confirm that the design approach to creep/fatigue currently being developed in the U.K. and based on ductility exhaustion is likely to be satisfactory. 相似文献
86.
87.
The dependence between the activity parameters of muscarine antagonists in the prevention of haloperidol catalepsy in rats and those in tests characterizing the interaction of ligands and various subtypes of m-cholinoceptors was studied. It was established by constructing the mathematical dependence that blockade of m1-cholinoceptors increases, while that of m2-cholinoceptors reduces the antiparkinsonian activity of the drugs. The activity of the muscarine antagonist pentiphan in the prevention of haloperidol-induced catalepsy in rats exceeds the activity of such traditional antiparkinsonian drugs as cyclodol and amedin. 相似文献
88.
K Sugahara Y Tanaka S Yamada N Seno H Kitagawa SM Haslam HR Morris A Dell 《Canadian Metallurgical Quarterly》1996,271(43):26745-26754
We prepared a series of oligosaccharides from king crab cartilage chondroitin sulfate K after exhaustive digestion with testicular hyaluronidase, and determined the structures of four tetrasaccharides and a pentasaccharide by fast atom bombardment mass spectrometry, high performance liquid chromatography analysis of chondroitinase AC-II digests, and 500-MHz 1H NMR spectroscopy. The tetrasaccharides shared the common core structure GlcAbeta1-3GalNAcbeta1-4GlcAbeta1-3GalNAc with various sulfation profiles. One structure was GlcAbeta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), whereas three of them have the following hitherto unreported structures including a novel glucuronate 3-O-sulfate: GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), GlcAbeta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), and GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), where 3S or 4S represents 3-O- or 4-O-sulfate, respectively. The structure of the pentasaccharide was determined as GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1- 3GalNAc(4S)beta1-4GlcA. Chondroitinase ABC digestion of the tetrasaccharides with GlcA(3S) at the internal position destroyed the disaccharide unit containing GlcA(3S) derived from the reducing side and resulted in only the disaccharide unit from the non-reducing side. In contrast, these tetrasaccharides remained totally resistant to chondroitinase AC-II. The results indicated that it is necessary to reevaluate the disaccharide composition of chondroitin sulfate poly- or oligosaccharides purified from various biological sources, since they were usually determined after chondroitinase ABC digestion. It is probable that the structures containing GlcA(3S) would not have been detected. 相似文献
89.
Tuberculous meningitis remains an important illness that can be difficult to diagnose in a timely fashion and carries significant morbidity. We present a retrospective review of the cases of tuberculous meningitis diagnosed and treated at a single institution. Fifty-eight cases were identified and stratified according to stage of disease at presentation. Four patients (7%) died; three (5%) developed severe neurological sequelae. Poor outcomes were largely confined to cases presenting in an advanced stage and at the extremes of age. Corticosteroids were administered to 56 patients and may have contributed to the comparatively good outcome in these cases. 相似文献
90.
Argues that children's failure on one of Piaget's best known tasks, conservation of solid quantity, reflects ignorance of physical properties rather than inadequate reasoning ability. The evidence for conservation itself, seen from the child's position, is analyzed. It is emphasized that children can learn and enjoy the concepts and methods of physics at much earlier ages than current orthodoxies would indicate. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献