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31.
OBJECTIVE: To determine whether neoadjuvant chemotherapy and radiotherapy for bony sarcomas extending into soft tissues would allow limb salvage yet maintain local disease control. DESIGN: A prospective cohort study. SETTING: A university-affiliated cancer centre in Alberta. PATIENTS: All patients with potentially curable, widely infiltrating bony sarcomas of the extremity without neurologic deficit, referred to the centre in the 6 years from January 1984 to December 1990. There were 11 patients; 1 did not complete the protocol. The mean follow-up was 24 months. INTERVENTIONS: Adriamycin (doxorubicin) was infused for 3 days at a rate of 30 mg/d. A few days later radiotherapy was given 5 days a week for 10 doses at a rate of 3.0 Gy per dose. Four to 5 weeks later the tumour was excised surgically, with placement of a bone allograft or prosthesis, allowing a 1-cm margin of healthy soft tissue and a 5-cm margin of healthy bone and marrow cavity whenever possible. MAIN OUTCOME MEASURES: Need for limb amputation, infectious complications, recurrence of local or regional disease. RESULTS: One patient underwent amputation after fracture through the tumour site. There were two postoperative infections, one acute and one chronic. All patients had full neurologic function of the distal limb. There was no local or regional recurrence of disease. CONCLUSION: Neoadjuvant chemotherapy followed by radiotherapy and tumour excision provides control of aggressive local bone sarcomas while maintaining limb integrity. 相似文献
32.
Verma Amar Kumar Nagpal Shivika Desai Aditya Sudha Radhika 《Neural computing & applications》2021,33(4):1297-1310
Neural Computing and Applications - Induction machines have extensive demand in industries as they are used for large-scale production and, therefore, vulnerable to both electrical and mechanical... 相似文献
33.
C. D. Daulatabad R. F. Ankalagi V. A. Desai 《European Journal of Lipid Science and Technology》1990,92(3):131-132
Seed oils of Stachytarpheta mutabilis, Petrea volubilis, Gmelina hystrix were examined for their component acids and were found to contain the following acids (wt. %): Capric (0.5, -, 1.3), Lauric (0.5, 5.9, 1.5), Myristic (1.0, 8.9, 2.3), Palmitic (7.7, 10.7, 29.2), Stearic (5.4, 20.9, 21.1), Arachidic (1.1, 3.5, 6.3), Behenic (1.0, 4.2, 4.7), Oleic (9.1, 42.1, 2.9) and Linoleic (73.7, 3.8, 30.7) respectively. 相似文献
34.
Addition of plasticizers to poly(vinyl chloride) generally increases its flammability and frequently increases smoke production during its burning. Flame retardants added to plasticized PVC can reduce flammability, but increase smoke production. This study shows that proper choice of combined use of other polymers, phosphate plasticizers, fillers and other flame retardants, produces measured synergistic improvements in flame retardance and smoke suppression which could benefit applications such as PVC wire and cable insulation. 相似文献
35.
A.c. impedance behaviour of MnO2 and doped -MnO2 electrodes in H2SO4 medium was assessed with a view to explaining the mechanism of the discharge behaviour of MnO2 electrodes in 4m H2SO4 electrolyte. The electrodes used in this work appear to be intermediate cases of planar and porous electrodes as the angles, , made by the low frequency part with the real axis are found to be in the range (30–60°). The Nyquist plots and the Randle plots tend to reinforce the observation made by Tye that the capacity yield is essentially diffusion controlled. The depression and flattening of semi-circles observed reveals a link with the heterogeneity of the planar electrode and with the porosity of the pitted electrode. The deviation from a 45° angle made by the low frequency part with the real axis may either be explained by the roughness of the electrode surface or the shallow pores on the surface of the electrodes; in other words due to the difference between the apparent and true surface areas. The double layer capacitance values of the electrodes seem to subsume adsorption capacitances and diffusion factors. Hence, the relative increase in magnitude. The electrodes appear to behave like planar electrodes when 10 µF is introduced into the circuit as a parallel capacitance since angles 0 vary between 40–58°. The undoped -MnO2 electrode, as well as those prepared from Li-MnO2, Ag-MnO2, and I.C.8, appear to be planar electrodes. 相似文献
36.
The effect of unreacted cement content on the processing, structure, and properties of macro-defect-free (MDF) composites fabricated from calcium aluminate cement (CAC), -alumina (Al2O3), and polyvinyl alcohol-acetate (PVAA) has been investigated. Three systems were formed with initial CAC: Al2O3 ratios of 5050, 3565, and 2575 by volume in their respective formulations. The amount of unreacted cement was reduced from 68.1 vol% which is present in standard (100% CAC) MDF cement, to 14.9 vol % for composites with an initial CAC: Al2O3 ratio of 2575, while the hydration product content was reduced from 18.1 vol % to 11.4 vol % for these respective systems. A hard core/soft shell continuum percolation model was used to determine that alumina substitution did not significantly affect the percolative nature of the interphase and bulk polymer regions. However, experiments showed that the reduction in unreacted cement content through Al2O3 substitution affected both the processing and microstructural features of these composites. The moisture absorption kinetics and flexural strength of composites exposed to 100% relative humidity were also evaluated, and it was found that their moisture sensitivity improved with decreasing unreacted cement content. A hypothesis is presented to explain the role of unreacted cement on the moisture sensitivity of these materials. 相似文献
37.
NS Kislitsina BA Katsnel'son LI Privalova OV Driakhlova 《Canadian Metallurgical Quarterly》1995,(10):31-34
The authors proved that animals having higher natural antioxidant activity and lower intensity of lipid peroxidation are more resistant to fibrogenic effects of quartz. The peritoneal macrophages obtained from those animals show higher resistance to quartz exposure "in vitro". Parameters characterizing antioxidant system should be included into a group of indexes describing propensity to silicosis. 相似文献
38.
J. D. Desai 《Journal of Materials Science: Materials in Electronics》2016,27(12):12329-12334
The preparative parameters have been optimized for NiO film formation in fabricated Spray Pyrolysis System using pneumatic air pressure driven aerosol formation. The structural studies by X-ray diffractometer (XRD) have been carried out to investigate crystallographic features. It was revealed that NiO crystallizes in cubic bunsenite structure. The optical band gap for direct transitions was found to be equal to 3.67 eV. Field Emission Scanning Electron Micrographs (FESEM) have been employed to study morphological aspects of the prepared films. The elemental depth profiles of film contents have been obtained Auger Electron Spectroscopic (AES) studies. 相似文献
39.
Protein structures are a very special class among all possible structures. It has been suggested that a "designability principle" plays a crucial role in nature's selection of protein sequences and structures. Here, we provide a theoretical base for such a selection principle, using a simple model of protein folding based on hydrophobic interactions. A structure is reduced to a string of 0s and 1s, which represent the surface and core sites, respectively, as the backbone is traced. Each structure is therefore associated with one point in a high dimensional space. Sequences are represented by strings of their hydrophobicities and thus can be mapped into the same space. A sequence that lies closer to a particular structure in this space than to any other structures will have that structure as its ground state. Atypical structures, namely those far away from other structures in the high dimensional space, have more sequences that fold into them and are thermodynamically more stable. We argue that the most common folds of proteins are the most atypical in the space of possible structures. 相似文献
40.
IuV Plastinina LI Privalova SIu Ter?shin BA Katsnel'son NS Kislitsina 《Canadian Metallurgical Quarterly》1996,(7):16-20
Experiments on white rats proved that the silicotic pulmonary changes slowed with the tails periodically immersed into iodine solution. Those pulmonary changes were due to inhalation of quartzite dust and especially due to intratracheal administration of standardized quartz dust DQ12. Influenced by inhalation of dust containing quartz, the rats demonstrated characteristic alterations in cytologic features of bronchial and alveolar lavage water. The "iodine baths" also declined those alterations, that may prove higher resistance of pulmonary macrophages to cytotoxic effects of quartz. This hypothesis finds a support in experiments with culture of rat peritoneal macrophages. If incubated in a medium with low iodine concentrations and subsequently washed off, the macrophages demonstrate lower incidence of cytotoxic effects due to the next incubation with particles of DQ12. The macrophage's higher resistance against cytotoxic agents is believed to result directly in antisilicotic effect of iodine, so "iodine baths" could be recommended for pathogenetic therapy and medical prophylaxis of silicosis. 相似文献